Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence.
INTRODUCTION — Clostridium difficile is a spore-forming, toxin-producing, gram-positive anaerobic bacterium that causes antibiotic-associated colitis. It colonizes the human intestinal tract after the normal gut flora has been altered by antibiotic therapy. C. difficile infection is one of the most common healthcare-associated infections and a significant cause of morbidity and mortality among older adult hospitalized patients.
The clinical manifestations and diagnosis of C. difficile infection will be reviewed here. The treatment, epidemiology, and prevention of C. difficile infection are discussed separately. (See "Clostridium difficile in adults: Treatment" and "Clostridium difficile in adults: Epidemiology, microbiology, and pathophysiology" and "Clostridium difficile infection: Prevention and control".)
CLINICAL MANIFESTATIONS — C. difficile infection (CDI) can cause a spectrum of manifestations ranging from an asymptomatic carriage to fulminant disease with toxic megacolon (table 1) [1,2]. The basis for this range of clinical manifestations is not fully understood but may be related to various host and pathogen factors. (See "Clostridium difficile in adults: Epidemiology, microbiology, and pathophysiology".)
Diarrhea with colitis — Watery diarrhea is the cardinal symptom of C. difficile–associated diarrhea (CDAD) with colitis (≥3 loose stools in 24 hours). Other manifestations include lower abdominal pain and cramping, low-grade fever, nausea, anorexia, and leukocytosis [2,3]. Diarrhea may be associated with mucus or occult blood, but melena or hematochezia are rare . Fever is associated with CDAD in about 15 percent of cases; temperature >38.5°C is a sign of severe C. difficile–associated diarrhea. Leukocytosis, elevated creatinine, and elevated lactate in the setting of CDAD are common; CDAD is routinely associated with an average white blood cell count of 15,000/microL.
Symptoms of CDI typically occur in the setting of antibiotic therapy; they may begin during antibiotic therapy or 5 to 10 days following antibiotic therapy. Rarely, symptoms present as late as 10 weeks after cessation of antibiotic therapy . The antibiotics most frequently implicated in predisposition to CDI are fluoroquinolones, clindamycin, cephalosporins, and penicillins, though virtually any antibiotic can predispose to CDI (table 2). Additional risk factors for CDI include age >65, recent hospitalization and use of proton pump inhibitors. (See "Clostridium difficile in adults: Epidemiology, microbiology, and pathophysiology", section on 'Risk factors'.)
Physical examination generally demonstrates lower abdominal tenderness. Lower gastrointestinal endoscopy (flexible proctoscopy, sigmoidoscopy, or colonoscopy) examination may demonstrate a spectrum of findings, from patchy mild erythema and friability to severe pseudomembranous colitis (severe inflammation of the inner lining of the bowel). (See 'Endoscopy' below.)
Unexplained leukocytosis in hospitalized patients (even in the absence of diarrhea) may reflect underlying CDI. In a prospective study of 60 patients with unexplained leukocytosis (white blood cell count >15,000/microL), positive stool C. difficile toxin was observed in 58 percent of cases compared with 12 percent in controls . When unexplained leukocytosis is due to CDI, diarrhea typically develops one to two days later. (See "Approach to the patient with neutrophilia", section on 'Infection'.)
Fulminant colitis — Clinical manifestations of fulminant colitis include diarrhea, lower quadrant or diffuse abdominal pain, abdominal distention, fever, hypovolemia, lactic acidosis, hypoalbuminemia, elevated creatinine, and marked leukocytosis (up to 40,000 white blood cells/microL or higher) [6-8].
Occasionally, CDI presents acutely as ileus, with little or no diarrhea. Diarrhea may be less prominent or absent due to pooling of secretions in a dilated, atonic colon. Such patients are usually severely ill, with colonic (and possibly small bowel) dilatation, often with colonic thickening, fever, and leukocytosis. In some cases, this presentation seems benign initially but progresses rapidly.
Complications of fulminant colitis include hypotension, sepsis, renal failure, toxic megacolon, and bowel perforation with peritonitis . Severe hypotension may occur in the setting of severe CDI and/or in the setting of bowel perforation with peritonitis. In addition, CDI may develop during antibiotic treatment for septic shock caused by a separate bacterial infection.
The diagnosis of toxic megacolon is established based on severe systemic toxicity together with radiographic evidence of colonic dilatation (>7 cm in its greatest diameter). Bowel perforation presents with abdominal rigidity, involuntary guarding, diminished bowel sounds, rebound tenderness, and severe localized tenderness in the left or right lower quadrants; abdominal radiographs may demonstrate free abdominal air. (See 'Radiographic imaging' below and "Toxic megacolon".)
Recurrent disease — Recurrent C. difficile infection is defined by complete abatement of CDI symptoms while on appropriate therapy, followed by subsequent reappearance of symptoms after treatment has been stopped. Up to 25 percent of patients experience recurrent C. difficile within 30 days of treatment . Less commonly, recurrent CDI can occur as late as three months after discontinuation of treatment. Once patients have experienced one recurrence, they are at significantly increased risk for further recurrences. (See "Clostridium difficile in adults: Epidemiology, microbiology, and pathophysiology", section on 'Recurrent infection'.)
Recurrent disease may be mild or severe . One study including more than 1500 patients with CDI noted 34 percent of patients with recurrent infection needed admission, 28 percent developed severe disease, and 4 percent developed a complication .
Risk factors for recurrence include age >65 years, severe underlying medical disorders, need for ongoing therapy with concomitant antibiotics during treatment for CDI, and lack of an antibody-mediated immune response to toxin B [13-17].
Recurrent symptoms may be due to relapse of the initial infecting strain or reinfection with a new strain [18-20]. Recurrent CDI often represents relapse rather than reinfection, regardless of the interval between episodes. Among 134 paired stool isolates from 102 patients with recurrent C. difficile infections, isolates obtained 2 to 8 weeks apart were identical in 88 percent of cases; isolates obtained 8 weeks to 11 months apart were identical in 65 percent of cases .
Persistent diarrhea without resolution during initial therapy should prompt an evaluation for other causes and should not be considered recurrent disease. In the absence of an alternative diagnosis, such patients should be considered to have refractory CDI.
Patients with recurrent diarrhea, cramping, and bloating following treatment of CDI may have postinfectious irritable bowel syndrome or another inflammatory colitis. (See 'Differential diagnosis' below.)
Asymptomatic carriage — Asymptomatic C. difficile carriage occurs in about 20 percent of hospitalized adults; these patients shed C. difficile in stool but do not have diarrhea or other clinical symptoms [22-24]. In long-term care facilities, the rate of asymptomatic colonization may approach 50 percent. These individuals serve as a reservoir for environmental contamination [23,24]. The host immune response to C. difficile may play a role in determining colonization status. Individuals with asymptomatic carriage of C. difficile do not warrant treatment, and there is no role for pursuing diagnostic evaluation for C. difficile infection in the absence of significant diarrhea. (See "Clostridium difficile in adults: Epidemiology, microbiology, and pathophysiology" and "Clostridium difficile infection: Prevention and control".)
Unusual presentations — Unusual manifestations of C. difficile include protein-losing enteropathy and extracolonic involvement.
●Protein-losing enteropathy – Protein-losing enteropathy with hypoalbuminemia has been described in association with acute C. difficile infection in the absence of fulminant colitis [25,26]. Inflammation of the bowel wall allows leakage of albumin into the lumen, causing colonic loss of albumin with inadequate compensatory hepatic synthesis. As a result, serum albumin levels may drop below 2.0 g/dL (20 g/L). Ascites and peripheral edema may be observed. The protein-losing enteropathy responds to appropriate medical therapy of the infection. (See "Protein-losing gastroenteropathy" and "Clostridium difficile in adults: Treatment".)
●Extracolonic involvement – Rare cases of C. difficile appendicitis, small bowel enteritis, and extraintestinal involvement have been described .
•Appendicitis due to C. difficile infection has been described in a few case reports; it may be underdiagnosed since relatively mild cases may respond to antibiotic therapy alone .
•Small bowel involvement with C. difficile enteritis typically occurs in older adults and/or patients with multiple comorbidities [29-31]. In some cases, patients have had prior colectomy with ileostomy; manifestations may include increased ileostomy output, and it may be possible to visualize pseudomembranes (severe inflammation of the inner lining of the bowel) on the ileostomy mucosa. Therefore, such patients may be at increased risk for fulminant disease with a high mortality rate [30,31].
•Rare cases of C. difficile cellulitis, soft tissue infection, bacteremia, and reactive arthritis have been described [29,32,33].
Overview of diagnostic approach — The diagnosis of C. difficile infection should be suspected in patients with clinically significant diarrhea (≥3 loose stools in 24 hours) or ileus in the setting of relevant risk factors (including recent antibiotic use, hospitalization, and advanced age). The diagnosis is established via a positive laboratory stool test for C. difficile toxins or C. difficile toxin gene. The diagnostic approach for suspected recurrent C. difficile is the same as the approach for initial infection. (See 'Diarrhea with colitis' above and "Clostridium difficile in adults: Epidemiology, microbiology, and pathophysiology", section on 'Risk factors'.)
For patients with diarrhea and suspected C. difficile infection, liquid stool should be sent for C. difficile testing. Laboratory testing does not distinguish between C. difficile–associated diarrhea (CDAD) and asymptomatic carriage (which does not warrant treatment); therefore, diagnostic laboratory testing should be pursued only in patients with clinically significant diarrhea [4,34-37].
For patients with ileus and suspected C. difficile infection, laboratory diagnosis via perirectal swab for toxin assay or anaerobic culture may be performed; the sensitivity of rectal swab for C. difficile culture in the setting of ileus is high (although takes time) [4,34,38,39].
Findings of pseudomembranous colitis (severe inflammation of the inner lining of the bowel) on radiographic or endoscopic examination are highly suggestive of C. difficile infection and should prompt laboratory testing [2,40-43].
There are several diagnostic tests available for the laboratory diagnosis of C. difficile infection, each with advantages and limitations. We favor use of polymerase chain reaction (PCR) for laboratory diagnosis of C. difficile, either alone or as part of an algorithm including initial enzyme immunoassay (EIA) screening for glutamate dehydrogenase (GDH) antigen and toxins A and B (algorithm 1) . A positive test result for C. difficile infection may be presumed in the setting of positive EIA for GDH antigen and toxin A or B, a negative result may be presumed if both EIAs are negative, and confirmatory PCR may be used if the EIA results are discordant [45-49]. An algorithmic approach may be less expensive but take slightly longer and has lower sensitivity than PCR alone . However, exclusive reliance on molecular testing may result in overdiagnosis and overtreatment, since laboratory testing cannot distinguish between CDAD and asymptomatic carriage (which does not warrant treatment) . Only one stool sample is needed for diagnosis of C. difficile with PCR (either alone or as part of an algorithm).
There is no role for repeat laboratory testing or testing for cure [4,51-57]. There is also no role for laboratory testing in asymptomatic patients or in patients receiving treatment for acute C. difficile infection; stool assays may remain positive during or after clinical recovery.
Radiographic imaging of the abdomen and pelvis is warranted for patients with clinical manifestations of severe illness or fulminant colitis (severe abdominal pain, abdominal distention with apparent ileus, fever, hypovolemia, lactic acidosis, hypoalbuminemia, and/or marked leukocytosis) to evaluate for presence of toxic megacolon, bowel perforation, or other findings warranting surgical intervention. Findings of pseudomembranous colitis on radiographic examination are highly suggestive of C. difficile infection and should prompt laboratory testing. (See 'Fulminant colitis' above and 'Radiographic imaging' below.)
Lower gastrointestinal endoscopy is not warranted in patients with classic clinical manifestations of C. difficile infection, a positive laboratory test, and/or clinical response to empiric treatment. In general, endoscopy may be pursued for circumstances in which an alternative diagnosis is suspected that requires direct visualization and/or biopsy of the bowel mucosa. It may also be helpful for patients with ileus or fulminant colitis in the absence of diarrhea since it may allow visualization of pseudomembranes (severe inflammation of the inner lining of the bowel), a finding that is highly suggestive of C. difficile infection. However, not all patients with CDAD have pseudomembranes, particularly patients with mild or partially treated infection, and absence of pseudomembranes does not rule out C. difficile infection. (See 'Endoscopy' below.)
Laboratory assays — Laboratory diagnosis of C. difficile infection requires demonstration of C. difficile toxin(s) or detection of toxigenic C. difficile organism(s) . We favor use of PCR for diagnosis of C. difficile on a single stool sample, either alone or as part of an algorithm including initial EIA screening for GDH antigen and toxins A and B (algorithm 1) [4,58-62]. A systematic review noted that single-step PCR or multistep algorithms using PCR for toxin gene(s) on liquid stool samples have the best test performance characteristics (single step testing: sensitivity 0.86 to 0.92 and specificity 0.94 to 0.97; multistep testing: sensitivity 0.68 to 1.0 and specificity 0.92 to 1.0) .
A number of laboratory stool tests are available, including [4,63]:
●Polymerase chain reaction
●Enzyme immunoassay for C. difficile glutamate dehydrogenase
●Enzyme immunoassay for C. difficile toxins A and B
●Cell culture cytotoxicity assay
●Selective anaerobic culture
These tests are discussed in further detail below.
●PCR testing – Real-time PCR tests detect one or more genes specific to toxigenic strains; the critical gene is tcdB, which encodes for toxin B. PCR is highly sensitive and specific [64-68]. The sensitivity of PCR is greater than EIA and comparable with cytotoxicity assay [4,69-73]. PCR is specific for toxigenic strains but does not test for active toxin production and is capable of detecting asymptomatic carriers of C. difficile; therefore, only liquid stool samples from patients with ≥3 loose stools in 24 hours should be tested. Only a single stool sample should be tested. PCR results can be available within as little as one hour. Given its high sensitivity and its inability to distinguish C. difficile infection from asymptomatic carriage, some favor use of PCR in an algorithm together with other assays such as EIA for GDH and EIA for toxins A and B. PCR results may be falsely negative if stool specimen collection is delayed and the patient treated empirically for suspected C. difficile infection . (See 'Overview of diagnostic approach' above.)
●EIA for C. difficile GDH antigen – GDH antigen is an essential enzyme produced constitutively by all C. difficile isolates; however, its detection cannot distinguish between toxigenic and nontoxigenic strains [60-62]. Therefore, testing for GDH antigen is useful as an initial screening step in a multistep approach, which also consists of subsequent testing with more specific assays such as toxin A and B EIA or PCR on specimens that are GDH antigen positive [4,59]. GDH antigen testing has good sensitivity, and results are available in less than one hour.
●EIA for C. difficile toxins A and B – Most C. difficile strains produce both toxins A and B, although some strains produce toxin A or B only [75-79]. Toxin B is the clinically important toxin; no CDAD due to toxin A alone has been reported. However, testing for both toxins by EIA gives a higher sensitivity than testing for toxin B alone. The sensitivity of EIA for toxins A and B is about 75 percent; the specificity is high (up to 99 percent) [4,80,81]. There is a relatively high false-negative rate since 100 to 1000 pg of toxin must be present for the test to be positive . A number of inexpensive assays are commercially available, and test results are available within hours . More than one stool sample may be tested.
●Selective anaerobic culture – Culture on selective medium with toxin testing of isolated C. difficile is the most sensitive diagnostic method, although culture cannot distinguish toxin-producing strains from non–toxin-producing strains . Use of a second test (EIA, PCR) is required to detect toxin production by cultured C. difficile strains. Culture followed by strain testing for toxin is considered by most to be the gold standard for diagnosis of C. difficile. Treatment of stool with heat or alcohol to shock spores (to increase vegetative growth) is sometimes used to improve yield. Culture is useful for epidemiologic studies but is generally too slow and labor intensive for routine clinical use . Perirectal swab for toxin assay or anaerobic culture can be a useful diagnostic tool for patients with ileus and suspected C. difficile infection.
●Cell culture cytotoxicity assay – The cell culture cytotoxicity assay was developed contemporaneously with the discovery of C. difficile and has been used as a gold standard test for diagnosis of C. difficile; it is more sensitive than enzyme immunoassay, although it is limited by lack of standardization and slow turnaround time (approximately two days) [83,84]. The cell culture cytotoxicity assay is performed by adding a prepared stool sample (diluted, buffered, and filtered) to a monolayer of cultured cells [40,85,86]. If C. difficile toxin is present, it exerts a cytopathic effect characterized by rounding of fibroblasts in tissue culture; specificity of the cytotoxicity is then demonstrated by neutralization of the cytopathic effect with specific antiserum.
It is important to note that C. difficile toxin degrades at room temperature and may be undetectable within two hours after collection; therefore, specimens for testing based on toxin detection (EIA for C. difficile toxins and cell culture cytotoxicity assay) should be kept at 4ºC if delay in laboratory testing is anticipated. In addition, a suspected outbreak should prompt freezing of stool samples for later investigation.
Fecal leukocyte testing is not helpful for diagnosis of C. difficile infection .
Adjunctive diagnostic tools — Adjunctive diagnostic tools for evaluating patients with suspected C. difficile infection include radiographic imaging and endoscopy.
Radiographic imaging — Radiographic imaging of the abdomen and pelvis is warranted for patients with clinical manifestations of severe illness or fulminant colitis (severe abdominal pain, abdominal distention with apparent ileus, fever, hypovolemia, lactic acidosis, hypoalbuminemia, and/or marked leukocytosis), to evaluate for presence of toxic megacolon, bowel perforation, or other findings warranting surgical intervention. Computed tomography (CT) of the abdomen and pelvis with oral and intravenous contrast is the preferred imaging modality; plain films may be useful for circumstances in which CT is not readily available.
Radiographic evidence of colonic dilatation (>7 cm in diameter) is diagnostic of toxic megacolon. Other radiographic findings consistent with toxic megacolon include small bowel dilatation, air-fluid levels (mimicking an intestinal obstruction or ischemia), and "thumb printing" (scalloping of the bowel wall) due to submucosal edema (image 1 and image 2). In the setting of bowel perforation, free abdominal air may be observed. (See "Toxic megacolon".)
Other radiographic findings associated with C. difficile colitis include pronounced colonic wall thickening (image 3) and low-attenuation mural thickening, corresponding with mucosal and submucosal edema (which may be visible as a "target sign" or "double halo sign" consisting of two or three concentric rings of different attenuation) . Pericolonic stranding and ascites may be seen but are not specific for C. difficile infection.
Findings consistent with pseudomembranous colitis (severe inflammation of the inner lining of the bowel) on radiographic examination are highly suggestive of C. difficile infection and should prompt laboratory testing if not already performed. The "accordion sign" is highly suggestive of pseudomembranous colitis; it consists of mucosal edema and inflammation involving the large bowel and is seen when orally administered contrast material becomes trapped between thickened haustral folds, giving the appearance of alternating bands of high attenuation (contrast material) and low attenuation (edematous haustra) [88-90]. (See 'Overview of diagnostic approach' above.)
Endoscopy — Lower gastrointestinal endoscopy is not warranted in patients with classic clinical manifestations of C. difficile infection, a positive laboratory test and/or clinical response to empiric treatment. In general, endoscopy may be pursued for circumstances in which an alternative diagnosis is suspected that requires direct visualization and/or biopsy of the bowel mucosa. It may also be helpful for patients with ileus or fulminant colitis in the absence of diarrhea since it may allow visualization of pseudomembranes (severe inflammation of the inner lining of the bowel), a finding that is highly suggestive of C. difficile infection. The decision to proceed with endoscopy should be made carefully; if pursued, flexible proctoscopy is preferred since insufflation with sigmoidoscopy and colonoscopy may damage potentially friable bowel tissue with increased risk for perforation.
Findings on lower gastrointestinal endoscopy in the setting of C. difficile infection include bowel wall edema, erythema, friability, and inflammation. When visible, findings of pseudomembranous colitis are highly suggestive of C. difficile infection and should prompt diagnostic laboratory confirmation if not already performed (via stool assay or, in the setting of ileus, a perirectal swab for toxin assay or anaerobic culture) . However, not all patients with CDAD have pseudomembranes, particularly patients with mild or partially treated infection, and absence of pseudomembranes does not rule out C. difficile infection. Pseudomembranes are rarely observed in the setting of recurrent C. difficile infection or inflammatory bowel disease [92,93]. There are rare reports of other pathogens also capable of causing pseudomembranous colitis (see 'Differential diagnosis' below).
Formation of pseudomembranes occurs following C difficile toxin–induced ulcer formation on the mucosal surface of the intestine, which facilitates release of serum proteins, mucus, and inflammatory cells . Pseudomembranes manifest as raised yellow or off-white plaques up to 2 cm in diameter scattered over the colonic mucosa (picture 1 and picture 2). Some patients with pseudomembranous colitis have scattered lesions with relatively normal-appearing intervening mucosa, while others have a confluent pseudomembrane covering the entire mucosa. Pseudomembranes may be absent in the rectosigmoid area but present more proximally, although colonoscopy for proximal evaluation of the colon is not warranted for diagnosis of C. difficile given potential bowel tissue friability and risk of perforation [91,95].
Biopsy is not needed for diagnosis of C. difficile. Biopsy may be warranted to establish an alternative diagnosis, particularly for patients who are not responding clinically to appropriate therapy for presumed C. difficile infection. (See 'Differential diagnosis' below.)
DIFFERENTIAL DIAGNOSIS — C. difficile must be distinguished from other infectious and noninfectious causes of diarrhea. Most antibiotic-associated diarrhea is not attributable to C. difficile infection (but rather to osmotic mechanisms), whereas antibiotic-associated diarrhea associated with colitis is nearly always C. difficile–associated diarrhea (CDAD).
●Acute abdomen – C. difficile may present as abdominal distension mimicking small bowel ileus, Ogilvie's syndrome, volvulus, or ischemia . The approach to diagnosis varies by age, gender and condition; tools include history and physical examination, surgical consultation, and radiographic imaging. (See "Evaluation of the adult with abdominal pain in the emergency department".)
●Shock – Severe hypotension may occur in the setting of severe C. difficile infection and/or in the setting of bowel perforation with peritonitis. In addition, C. difficile infection may develop during antibiotic treatment for septic shock caused by a separate bacterial infection. Shock due to other causes (such as septic shock or cardiogenic shock) must be distinguished from severe hypotension due to C. difficile infection via cardiac and hemodynamic assessment. (See "Evaluation of and initial approach to the adult patient with undifferentiated hypotension and shock".)
●Infectious diarrhea – Other organisms that have been implicated as causes of antibiotic-associated diarrhea include Staphylococcus aureus , Klebsiella oxytoca , Clostridium perfringens , and possibly Candida albicans . Salmonella can present as a pseudomembranous colitis (severe inflammation of the inner lining of the bowel) . The clinical manifestations are similar to that of C. difficile infection; the diagnosis is distinguished by stool culture.
●Noninfectious diarrhea – Causes of noninfectious diarrhea that may mimic C. difficile infection include postinfectious irritable bowel syndrome, inflammatory bowel disease, celiac disease, and collagenous colitis. Differentiation of noninfectious antibiotic-associated diarrhea from C. difficile infection may be difficult, especially in patients who are asymptomatic C. difficile carriers; this is most relevant among patients in nursing homes or hospitals where the rate of asymptomatic carriage is 10 to 50 percent (in community populations, the rate of asymptomatic carriage is ≤5 percent). Cessation of symptoms with discontinuation of oral intake is a distinguishing feature of osmotic diarrhea (figure 1). The presence of fever and leukocytosis favors C. difficile or other infectious etiology. (See "Approach to the adult with chronic diarrhea in resource-rich settings".)
•Postinfectious irritable bowel syndrome – Postinfectious irritable bowel syndrome occurs in about 10 percent of patients who have been successfully treated for an initial episode of C. difficile. These patients may have up to 10 watery stools per day; this must be distinguished from a relapse of the original C. difficile infection based on established criteria (table 3). (See "Clinical manifestations and diagnosis of irritable bowel syndrome in adults".)
•Inflammatory bowel disease – Infection with C. difficile may complicate the course of inflammatory bowel disease (IBD) [101,102]. Enteric infections account for about 10 percent of symptomatic relapses in patients with IBD; C. difficile accounts for about half of these infections . Rates of C. difficile among patients with IBD appear to be increasing [104,105]. The association between IBD and C. difficile may be due to a variety of factors, including antibiotic use for treatment of other gastrointestinal pathogens and frequent hospitalization for management of IBD flares. Rarely, C. difficile can trigger an initial bout of IBD .
C. difficile infection in patients with IBD requires prompt diagnosis and management, since failure to diagnose the infection can lead to inappropriate treatment with glucocorticoids or immunosuppressive therapy. Furthermore, C. difficile may be difficult to distinguish from an IBD relapse given the similar symptoms of diarrhea, abdominal pain, and low-grade fever. Thus, a high index of suspicion is required when evaluating IBD patients with apparent flares, especially those who have recently received antibiotics and/or been hospitalized.
The diagnosis requires laboratory testing; endoscopy is usually not helpful because IBD patients generally do not develop pseudomembranes. Given preexisting colonic pathology, patients with IBD who develop C. difficile colitis require colectomy more frequently (20 percent in one series) .
There is a high prevalence of C. difficile carriage in patients with IBD. This was illustrated in a study of 122 patients with longstanding IBD in which the frequency of C. difficile carriage was higher in IBD patients than in healthy volunteers (8 versus 1 percent, respectively), in the absence of recent antibiotics or hospitalization . Despite this observation, none developed symptomatic disease in the subsequent six months. The reason for this observation is not certain; possibilities include altered colonic microbial flora, mucosal inflammation, and impaired mucosal innate immunity.
•Collagenous colitis – Collagenous colitis is a chronic inflammatory disease of the colon characterized by chronic, watery diarrhea. The diagnosis is established via colonoscopy with biopsy. (See "Lymphocytic and collagenous colitis (microscopic colitis): Clinical manifestations, diagnosis, and management".)
•Celiac disease – Celiac disease is a small bowel disease associated with dietary gluten exposure; gastrointestinal symptoms including chronic or recurrent diarrhea, malabsorption, weight loss, and abdominal distension or bloating. The diagnosis is established via serology and/or biopsy. (See "Diagnosis of celiac disease in adults".)
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Clostridium difficile infection".)
INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, “The Basics” and “Beyond the Basics.” The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on “patient info” and the keyword(s) of interest.)
●Beyond the Basics topics (see "Patient education: Antibiotic-associated diarrhea caused by Clostridium difficile (Beyond the Basics)")
●Clostridium difficile colonizes the human intestinal tract after the normal gut flora has been altered by antibiotic therapy and causes antibiotic-associated colitis. The antibiotics most frequently implicated in predisposition to C. difficile infection are fluoroquinolones, clindamycin, cephalosporins, and penicillins (table 2). Additional risk factors include age >65 and recent hospitalization. (See 'Diarrhea with colitis' above.)
•Clinical manifestations of C. difficile–associated diarrhea (CDAD) with colitis include watery diarrhea (≥3 loose stools in 24 hours) with lower abdominal pain and cramping, low-grade fever, and leukocytosis. (See 'Diarrhea with colitis' above.)
•Clinical manifestations of fulminant colitis include diarrhea, severe lower quadrant or diffuse abdominal pain, abdominal distention, fever, hypovolemia, lactic acidosis, hypoalbuminemia, and marked leukocytosis. Diarrhea may be less prominent or absent in patients with prolonged ileus due to pooling of secretions in the dilated, atonic colon. Potential complications include toxic megacolon and bowel perforation. (See 'Fulminant colitis' above.)
●Recurrence C. difficile infection is defined by complete abatement of symptoms while on appropriate therapy, followed by subsequent reappearance of diarrhea and other symptoms after treatment has ended. Relapse may present within days or weeks of completing treatment for C. difficile; the clinical presentation may be similar to or more severe than the initial presentation. (See 'Recurrent disease' above.)
●The diagnosis of C. difficile infection is established via a positive stool test for C. difficile toxins or C. difficile toxin gene. We favor use of polymerase chain reaction for laboratory diagnosis of C. difficile, either alone or as part of an algorithm including initial enzyme immunoassay screening for glutamate dehydrogenase antigen and toxins A and B (algorithm 1). The diagnostic approach for suspected recurrent C. difficile is the same as the approach for initial infection. (See 'Overview of diagnostic approach' above.)
●Laboratory testing should be pursued only in patients with clinically significant diarrhea, since testing cannot distinguish between CDAD and asymptomatic carriage (which does not warrant treatment). For patients with ileus, laboratory diagnosis via perirectal swab for toxin assay or anaerobic culture may be performed. (See 'Overview of diagnostic approach' above.)
●Radiographic imaging of the abdomen and pelvis is warranted for patients with clinical manifestations of severe illness or fulminant colitis to evaluate for presence of toxic megacolon, bowel perforation, or other findings warranting surgical intervention. (See 'Overview of diagnostic approach' above and 'Radiographic imaging' above.)
●Lower gastrointestinal endoscopy is not warranted in patients with classic clinical manifestations of C. difficile infection, a positive laboratory test, and/or clinical response to empiric treatment. In general, endoscopy may be pursued for circumstances in which an alternative diagnosis is suspected that requires direct visualization and/or biopsy of the bowel mucosa. It may also be helpful for patients with ileus or fulminant colitis in the absence of diarrhea since it may allow visualization of pseudomembranes (severe inflammation of the inner lining of the bowel), a finding that is highly suggestive of C. difficile infection. (See 'Endoscopy' above.)
●Findings of pseudomembranous colitis (severe inflammation of the inner lining of the bowel) on radiographic or endoscopic examination are highly suggestive of C. difficile infection and should prompt laboratory testing if not already performed. (See 'Radiographic imaging' above and 'Endoscopy' above.)
- Kelly CP, LaMont JT. Clostridium difficile--more difficult than ever. N Engl J Med 2008; 359:1932.
- Bagdasarian N, Rao K, Malani PN. Diagnosis and treatment of Clostridium difficile in adults: a systematic review. JAMA 2015; 313:398.
- Wanahita A, Goldsmith EA, Musher DM. Conditions associated with leukocytosis in a tertiary care hospital, with particular attention to the role of infection caused by clostridium difficile. Clin Infect Dis 2002; 34:1585.
- Cohen SH, Gerding DN, Johnson S, et al. Clinical practice guidelines for Clostridium difficile infection in adults: 2010 update by the society for healthcare epidemiology of America (SHEA) and the infectious diseases society of America (IDSA). Infect Control Hosp Epidemiol 2010; 31:431.
- Tedesco FJ. Pseudomembranous colitis: pathogenesis and therapy. Med Clin North Am 1982; 66:655.
- Wanahita A, Goldsmith EA, Marino BJ, Musher DM. Clostridium difficile infection in patients with unexplained leukocytosis. Am J Med 2003; 115:543.
- Bulusu M, Narayan S, Shetler K, Triadafilopoulos G. Leukocytosis as a harbinger and surrogate marker of Clostridium difficile infection in hospitalized patients with diarrhea. Am J Gastroenterol 2000; 95:3137.
- Walk ST, Micic D, Jain R, et al. Clostridium difficile ribotype does not predict severe infection. Clin Infect Dis 2012; 55:1661.
- Rubin MS, Bodenstein LE, Kent KC. Severe Clostridium difficile colitis. Dis Colon Rectum 1995; 38:350.
- Kelly CP. Can we identify patients at high risk of recurrent Clostridium difficile infection? Clin Microbiol Infect 2012; 18 Suppl 6:21.
- Fekety R, McFarland LV, Surawicz CM, et al. Recurrent Clostridium difficile diarrhea: characteristics of and risk factors for patients enrolled in a prospective, randomized, double-blinded trial. Clin Infect Dis 1997; 24:324.
- Sheitoyan-Pesant C, Abou Chakra CN, Pépin J, et al. Clinical and Healthcare Burden of Multiple Recurrences of Clostridium difficile Infection. Clin Infect Dis 2016; 62:574.
- Hu MY, Katchar K, Kyne L, et al. Prospective derivation and validation of a clinical prediction rule for recurrent Clostridium difficile infection. Gastroenterology 2009; 136:1206.
- Tedesco FJ, Gordon D, Fortson WC. Approach to patients with multiple relapses of antibiotic-associated pseudomembranous colitis. Am J Gastroenterol 1985; 80:867.
- Kyne L, Warny M, Qamar A, Kelly CP. Association between antibody response to toxin A and protection against recurrent Clostridium difficile diarrhoea. Lancet 2001; 357:189.
- Pépin J, Routhier S, Gagnon S, Brazeau I. Management and outcomes of a first recurrence of Clostridium difficile-associated disease in Quebec, Canada. Clin Infect Dis 2006; 42:758.
- Gupta SB, Mehta V, Dubberke ER, et al. Antibodies to Toxin B Are Protective Against Clostridium difficile Infection Recurrence. Clin Infect Dis 2016; 63:730.
- Walters BA, Roberts R, Stafford R, Seneviratne E. Relapse of antibiotic associated colitis: endogenous persistence of Clostridium difficile during vancomycin therapy. Gut 1983; 24:206.
- Young G, McDonald M. Antibiotic-associated colitis: why do patients relapse? Gastroenterology 1986; 90:1098.
- Wilcox MH, Fawley WN, Settle CD, Davidson A. Recurrence of symptoms in Clostridium difficile infection--relapse or reinfection? J Hosp Infect 1998; 38:93.
- Kamboj M, Khosa P, Kaltsas A, et al. Relapse versus reinfection: surveillance of Clostridium difficile infection. Clin Infect Dis 2011; 53:1003.
- Kyne L, Warny M, Qamar A, Kelly CP. Asymptomatic carriage of Clostridium difficile and serum levels of IgG antibody against toxin A. N Engl J Med 2000; 342:390.
- McFarland LV, Mulligan ME, Kwok RY, Stamm WE. Nosocomial acquisition of Clostridium difficile infection. N Engl J Med 1989; 320:204.
- Riggs MM, Sethi AK, Zabarsky TF, et al. Asymptomatic carriers are a potential source for transmission of epidemic and nonepidemic Clostridium difficile strains among long-term care facility residents. Clin Infect Dis 2007; 45:992.
- Dansinger ML, Johnson S, Jansen PC, et al. Protein-losing enteropathy is associated with Clostridium difficile diarrhea but not with asymptomatic colonization: a prospective, case-control study. Clin Infect Dis 1996; 22:932.
- Rybolt AH, Bennett RG, Laughon BE, et al. Protein-losing enteropathy associated with Clostridium difficile infection. Lancet 1989; 1:1353.
- Mattila E, Arkkila P, Mattila PS, et al. Extraintestinal Clostridium difficile infections. Clin Infect Dis 2013; 57:e148.
- Brown TA, Rajappannair L, Dalton AB, et al. Acute appendicitis in the setting of Clostridium difficile colitis: case report and review of the literature. Clin Gastroenterol Hepatol 2007; 5:969.
- Jacobs A, Barnard K, Fishel R, Gradon JD. Extracolonic manifestations of Clostridium difficile infections. Presentation of 2 cases and review of the literature. Medicine (Baltimore) 2001; 80:88.
- Hayetian FD, Read TE, Brozovich M, et al. Ileal perforation secondary to Clostridium difficile enteritis: report of 2 cases. Arch Surg 2006; 141:97.
- Vesoulis Z, Williams G, Matthews B. Pseudomembranous enteritis after proctocolectomy: report of a case. Dis Colon Rectum 2000; 43:551.
- Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 19-1998. A 70-year-old man with diarrhea, polyarthritis, and a history of Reiter's syndrome. N Engl J Med 1998; 338:1830.
- Gupta A, Patel R, Baddour LM, et al. Extraintestinal Clostridium difficile infections: a single-center experience. Mayo Clin Proc 2014; 89:1525.
- Gerding DN, Johnson S, Peterson LR, et al. Clostridium difficile-associated diarrhea and colitis. Infect Control Hosp Epidemiol 1995; 16:459.
- Sunenshine RH, McDonald LC. Clostridium difficile-associated disease: new challenges from an established pathogen. Cleve Clin J Med 2006; 73:187.
- Gerding DN. Diagnosis of Clostridium difficile--associated disease: patient selection and test perfection. Am J Med 1996; 100:485.
- Katz DA, Lynch ME, Littenberg B. Clinical prediction rules to optimize cytotoxin testing for Clostridium difficile in hospitalized patients with diarrhea. Am J Med 1996; 100:487.
- Peterson LR, Robicsek A. Does my patient have Clostridium difficile infection? Ann Intern Med 2009; 151:176.
- Kundrapu S, Sunkesula VC, Jury LA, et al. Utility of perirectal swab specimens for diagnosis of Clostridium difficile infection. Clin Infect Dis 2012; 55:1527.
- Kelly CP, Pothoulakis C, LaMont JT. Clostridium difficile colitis. N Engl J Med 1994; 330:257.
- Dubberke ER, Gerding DN, Classen D, et al. Strategies to prevent clostridium difficile infections in acute care hospitals. Infect Control Hosp Epidemiol 2008; 29 Suppl 1:S81.
- Crobach MJ, Dekkers OM, Wilcox MH, Kuijper EJ. European Society of Clinical Microbiology and Infectious Diseases (ESCMID): data review and recommendations for diagnosing Clostridium difficile-infection (CDI). Clin Microbiol Infect 2009; 15:1053.
- Department of Health. Health Protection Agency. Clostridium difficile infection: How to deal with the problem. Department of Health London 2008. Available at: www.hpa.org.uk/webw/HPAweb&HPAwebStandard/HPAweb_C/1204186173530?p=1263812760663 (Accessed on April 01, 2010).
- Leffler DA, Lamont JT. Clostridium difficile infection. N Engl J Med 2015; 372:1539.
- Goldenberg SD, Cliff PR, Smith S, et al. Two-step glutamate dehydrogenase antigen real-time polymerase chain reaction assay for detection of toxigenic Clostridium difficile. J Hosp Infect 2010; 74:48.
- Novak-Weekley SM, Marlowe EM, Miller JM, et al. Clostridium difficile testing in the clinical laboratory by use of multiple testing algorithms. J Clin Microbiol 2010; 48:889.
- Brecher SM, Novak-Weekley SM, Nagy E. Laboratory diagnosis of Clostridium difficile infections: there is light at the end of the colon. Clin Infect Dis 2013; 57:1175.
- Debast SB, Bauer MP, Kuijper EJ, European Society of Clinical Microbiology and Infectious Diseases. European Society of Clinical Microbiology and Infectious Diseases: update of the treatment guidance document for Clostridium difficile infection. Clin Microbiol Infect 2014; 20 Suppl 2:1.
- Planche TD, Davies KA, Coen PG, et al. Differences in outcome according to Clostridium difficile testing method: a prospective multicentre diagnostic validation study of C difficile infection. Lancet Infect Dis 2013; 13:936.
- Polage CR, Gyorke CE, Kennedy MA, et al. Overdiagnosis of Clostridium difficile Infection in the Molecular Test Era. JAMA Intern Med 2015; 175:1792.
- Manabe YC, Vinetz JM, Moore RD, et al. Clostridium difficile colitis: an efficient clinical approach to diagnosis. Ann Intern Med 1995; 123:835.
- Deshpande A, Pasupuleti V, Patel P, et al. Repeat stool testing to diagnose Clostridium difficile infection using enzyme immunoassay does not increase diagnostic yield. Clin Gastroenterol Hepatol 2011; 9:665.
- Cardona DM, Rand KH. Evaluation of repeat Clostridium difficile enzyme immunoassay testing. J Clin Microbiol 2008; 46:3686.
- Mohan SS, McDermott BP, Parchuri S, Cunha BA. Lack of value of repeat stool testing for Clostridium difficile toxin. Am J Med 2006; 119:356.e7.
- Renshaw AA, Stelling JM, Doolittle MH. The lack of value of repeated Clostridium difficile cytotoxicity assays. Arch Pathol Lab Med 1996; 120:49.
- Aichinger E, Schleck CD, Harmsen WS, et al. Nonutility of repeat laboratory testing for detection of Clostridium difficile by use of PCR or enzyme immunoassay. J Clin Microbiol 2008; 46:3795.
- Gade R, Turett G. The utility of repeated stool toxin testing for diagnosing Clostridium difficile colitis. South Med J 2009; 102:1007.
- Ferry G, Versalovic J. Antibiotic-associated colitis. In: Textbook of Pediatric Infectious Diseases, 6th ed, Feigin RD, Cherry JD, Demmler-Harrison GJ, Kaplan SL (Eds), Saunders, Philadelphia 2009. p.653.
- Wilkins TD, Lyerly DM. Clostridium difficile testing: after 20 years, still challenging. J Clin Microbiol 2003; 41:531.
- Ticehurst JR, Aird DZ, Dam LM, et al. Effective detection of toxigenic Clostridium difficile by a two-step algorithm including tests for antigen and cytotoxin. J Clin Microbiol 2006; 44:1145.
- Reller ME, Lema CA, Perl TM, et al. Yield of stool culture with isolate toxin testing versus a two-step algorithm including stool toxin testing for detection of toxigenic Clostridium difficile. J Clin Microbiol 2007; 45:3601.
- Fenner L, Widmer AF, Goy G, et al. Rapid and reliable diagnostic algorithm for detection of Clostridium difficile. J Clin Microbiol 2008; 46:328.
- Kufelnicka AM, Kirn TJ. Effective utilization of evolving methods for the laboratory diagnosis of Clostridium difficile infection. Clin Infect Dis 2011; 52:1451.
- Luo RF, Banaei N. Is repeat PCR needed for diagnosis of Clostridium difficile infection? J Clin Microbiol 2010; 48:3738.
- Bélanger SD, Boissinot M, Clairoux N, et al. Rapid detection of Clostridium difficile in feces by real-time PCR. J Clin Microbiol 2003; 41:730.
- van den Berg RJ, Bruijnesteijn van Coppenraet LS, Gerritsen HJ, et al. Prospective multicenter evaluation of a new immunoassay and real-time PCR for rapid diagnosis of Clostridium difficile-associated diarrhea in hospitalized patients. J Clin Microbiol 2005; 43:5338.
- Longtin Y, Trottier S, Brochu G, et al. Impact of the type of diagnostic assay on Clostridium difficile infection and complication rates in a mandatory reporting program. Clin Infect Dis 2013; 56:67.
- Surawicz CM, Brandt LJ, Binion DG, et al. Guidelines for diagnosis, treatment, and prevention of Clostridium difficile infections. Am J Gastroenterol 2013; 108:478.
- Kvach EJ, Ferguson D, Riska PF, Landry ML. Comparison of BD GeneOhm Cdiff real-time PCR assay with a two-step algorithm and a toxin A/B enzyme-linked immunosorbent assay for diagnosis of toxigenic Clostridium difficile infection. J Clin Microbiol 2010; 48:109.
- Stamper PD, Babiker W, Alcabasa R, et al. Evaluation of a new commercial TaqMan PCR assay for direct detection of the clostridium difficile toxin B gene in clinical stool specimens. J Clin Microbiol 2009; 47:3846.
- Eastwood K, Else P, Charlett A, Wilcox M. Comparison of nine commercially available Clostridium difficile toxin detection assays, a real-time PCR assay for C. difficile tcdB, and a glutamate dehydrogenase detection assay to cytotoxin testing and cytotoxigenic culture methods. J Clin Microbiol 2009; 47:3211.
- Stamper PD, Alcabasa R, Aird D, et al. Comparison of a commercial real-time PCR assay for tcdB detection to a cell culture cytotoxicity assay and toxigenic culture for direct detection of toxin-producing Clostridium difficile in clinical samples. J Clin Microbiol 2009; 47:373.
- van den Berg RJ, Vaessen N, Endtz HP, et al. Evaluation of real-time PCR and conventional diagnostic methods for the detection of Clostridium difficile-associated diarrhoea in a prospective multicentre study. J Med Microbiol 2007; 56:36.
- Sunkesula VC, Kundrapu S, Muganda C, et al. Does empirical Clostridium difficile infection (CDI) therapy result in false-negative CDI diagnostic test results? Clin Infect Dis 2013; 57:494.
- Limaye AP, Turgeon DK, Cookson BT, Fritsche TR. Pseudomembranous colitis caused by a toxin A(-) B(+) strain of Clostridium difficile. J Clin Microbiol 2000; 38:1696.
- Barbut F, Lalande V, Burghoffer B, et al. Prevalence and genetic characterization of toxin A variant strains of Clostridium difficile among adults and children with diarrhea in France. J Clin Microbiol 2002; 40:2079.
- Johnson S, Kent SA, O'Leary KJ, et al. Fatal pseudomembranous colitis associated with a variant clostridium difficile strain not detected by toxin A immunoassay. Ann Intern Med 2001; 135:434.
- Knapp CC, Sandin RL, Hall GS, et al. Comparison of vidas Clostridium difficile toxin-A assay and premier C. difficile toxin-A assay to cytotoxin-B tissue culture assay for the detection of toxins of C. difficile. Diagn Microbiol Infect Dis 1993; 17:7.
- Lyras D, O'Connor JR, Howarth PM, et al. Toxin B is essential for virulence of Clostridium difficile. Nature 2009; 458:1176.
- Blossom DB, McDonald LC. The challenges posed by reemerging Clostridium difficile infection. Clin Infect Dis 2007; 45:222.
- Swindells J, Brenwald N, Reading N, Oppenheim B. Evaluation of diagnostic tests for Clostridium difficile infection. J Clin Microbiol 2010; 48:606.
- Bartlett JG. Clinical practice. Antibiotic-associated diarrhea. N Engl J Med 2002; 346:334.
- Shanholtzer CJ, Willard KE, Holter JJ, et al. Comparison of the VIDAS Clostridium difficile toxin A immunoassay with C. difficile culture and cytotoxin and latex tests. J Clin Microbiol 1992; 30:1837.
- Laughon BE, Viscidi RP, Gdovin SL, et al. Enzyme immunoassays for detection of Clostridium difficile toxins A and B in fecal specimens. J Infect Dis 1984; 149:781.
- Shannon-Lowe J, Matheson NJ, Cooke FJ, Aliyu SH. Prevention and medical management of Clostridium difficile infection. BMJ 2010; 340:c1296.
- Singh N, Hyun DY. Clostridium difficile. In: Principles and Practice of Pediatric Infectious Diseases, 4th ed, Long SS, Pickering LK, Prober CG (Eds), Elsevier Saunders, Edinburgh 2012. p.977.
- Reddymasu S, Sheth A, Banks DE. Is Fecal Leukocyte Test a good predictor of Clostridium difficile associated diarrhea? Ann Clin Microbiol Antimicrob 2006; 5:9.
- Kawamoto S, Horton KM, Fishman EK. Pseudomembranous colitis: spectrum of imaging findings with clinical and pathologic correlation. Radiographics 1999; 19:887.
- Valiquette L, Pépin J, Do XV, et al. Prediction of complicated Clostridium difficile infection by pleural effusion and increased wall thickness on computed tomography. Clin Infect Dis 2009; 49:554.
- Lim J, Phillips AW, Thomson WL. An unexpected CT finding in a patient with abdominal pain. BMJ Case Rep 2013; 2013.
- Tedesco FJ. Antibiotic associated pseudomembranous colitis with negative proctosigmoidoscopy examination. Gastroenterology 1979; 77:295.
- Goodhand JR, Alazawi W, Rampton DS. Systematic review: Clostridium difficile and inflammatory bowel disease. Aliment Pharmacol Ther 2011; 33:428.
- Ananthakrishnan AN, Binion DG. Impact of Clostridium difficile on inflammatory bowel disease. Expert Rev Gastroenterol Hepatol 2010; 4:589.
- Riegler M, Sedivy R, Pothoulakis C, et al. Clostridium difficile toxin B is more potent than toxin A in damaging human colonic epithelium in vitro. J Clin Invest 1995; 95:2004.
- Seppälä K, Hjelt L, Sipponen P. Colonoscopy in the diagnosis of antibiotic-associated colitis. A prospective study. Scand J Gastroenterol 1981; 16:465.
- Triadafilopoulos G, Hallstone AE. Acute abdomen as the first presentation of pseudomembranous colitis. Gastroenterology 1991; 101:685.
- Gravet A, Rondeau M, Harf-Monteil C, et al. Predominant Staphylococcus aureus isolated from antibiotic-associated diarrhea is clinically relevant and produces enterotoxin A and the bicomponent toxin LukE-lukD. J Clin Microbiol 1999; 37:4012.
- Högenauer C, Langner C, Beubler E, et al. Klebsiella oxytoca as a causative organism of antibiotic-associated hemorrhagic colitis. N Engl J Med 2006; 355:2418.
- Sparks SG, Carman RJ, Sarker MR, McClane BA. Genotyping of enterotoxigenic Clostridium perfringens fecal isolates associated with antibiotic-associated diarrhea and food poisoning in North America. J Clin Microbiol 2001; 39:883.
- Hovius SE, Rietra PJ. Salmonella colitis clinically presenting as a pseudomembranous colitis. Neth J Surg 1982; 34:81.
- LaMont JT, Trnka YM. Therapeutic implications of Clostridium difficile toxin during relapse of chronic inflammatory bowel disease. Lancet 1980; 1:381.
- Greenfield C, Aguilar Ramirez JR, Pounder RE, et al. Clostridium difficile and inflammatory bowel disease. Gut 1983; 24:713.
- Mylonaki M, Langmead L, Pantes A, et al. Enteric infection in relapse of inflammatory bowel disease: importance of microbiological examination of stool. Eur J Gastroenterol Hepatol 2004; 16:775.
- Rodemann JF, Dubberke ER, Reske KA, et al. Incidence of Clostridium difficile infection in inflammatory bowel disease. Clin Gastroenterol Hepatol 2007; 5:339.
- Issa M, Vijayapal A, Graham MB, et al. Impact of Clostridium difficile on inflammatory bowel disease. Clin Gastroenterol Hepatol 2007; 5:345.
- Clayton EM, Rea MC, Shanahan F, et al. The vexed relationship between Clostridium difficile and inflammatory bowel disease: an assessment of carriage in an outpatient setting among patients in remission. Am J Gastroenterol 2009; 104:1162.