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mckittrick - wheelock syndrome , which is a disorder characterized by fluid and electrolyte depletion , is caused by a secretory colorectal tumor [ 1 - 3 ] .
the main clinical features of mckittrick - wheelock syndrome are dehydration , mucous diarrhea , and symptoms of hyponatremia ( headache , nausea , weakness , muscle cramps , lethargy , and seizures ) , and hypokalemia ( fatigue , paresthesias , cramps , ileus , vomiting , hypotension , cardiac arrhythmias , and electrocardiographic changes ) .
endoscopic resection is frequently difficult owing to the large size , unfavorable location , extension , or malignant change of the tumor .
laparoscopic surgical resection is an effective , rapid , and safe alternative in such cases .
we describe the case of a 59-year - old man who suffered from diarrhea , acute renal failure , and electrolyte disturbances caused by a giant rectal villous tumor .
a 59-year - old man arrived in our emergency department with the sudden onset of syncope . on arrival , he was clinically dehydrated , with reduced skin turgor and dry mucous membranes .
examination revealed that the patient had decreased blood pressure ( 70/50 mmhg ) and an increased heart rate ( 94 beats / min ) .
laboratory tests revealed a serum sodium ( na ) level of 122 mmol / l , potassium ( k ) level of 1.7 mmol / l , blood urea nitrogen ( bun ) level of 96 mg / dl , and creatinine ( cr ) level of 2.6 mg / l . the peripheral blood leukocyte count was 8.05  10 leukocytes/l , hemoglobin was 17.4 g / dl , and platelet count was 449  10 platelets/l .
a central venous catheter and urinary catheter was inserted to monitor the central venous pressure and urine output .
after hydration by intravenous isotonic saline and potassium chloride ( 20 mgeq / l ) replacement , the patient 's blood pressure recovered ( 118/78 mmhg ) , but he remained potassium - depleted ( 2.0 mmol / l ) in the emergency room .
after subsequent resuscitation , all physical and serological parameters were normalized and maintained ( na , 138 mmol / l ; k , 3.8 mmol / l ; bun , 16 mg / dl ; cr , 1.1 mg / dl ) .
a detailed review of his history revealed that the patient had been suffering from chronic diarrhea for approximately 10 years . except for this condition
however , in the past month , the diarrhea had worsened ( more than 20 times a day ) , and he felt progressive malaise and frequent cramps in his legs .
digital rectal examination revealed a huge , firm tumor with a velvety surface on the whole circumference of the rectum , 7 cm from the anal verge .
an abdominal computed tomography ( ct ) scan was performed to check the lesion ; it revealed a huge mass throughout the rectum and distal sigmoid colon ( fig .
full colonoscopy also demonstrated huge conglomerated polyps in the rectosigmoid colon ; the other part of the colon was unremarkable ( fig .
2 ) . on the seventh day of hospitalization , a laparoscopic low anterior resection with high ligation of the inferior mesenteric artery was carried out .
the laparoscopic technique was hampered by the distension of the rectal ampulla owing to the intrarectal huge tumor and mucus .
thus , the distal part of the lesion was resected twice to ensure a safe distal margin , as the distal resection margin ( drm ) was free from adenoma , and drm length was 8 cm while proximal resection margin length was 39 cm in the pathological report ; however , the other part of the specimen was not photographed ( fig .
however , the soft feature of the lesion did not preclude adequate visualization of the pelvic structures .
therefore , a standard low anterior resection with total mesorectal excision and high ligation of the inferior mesenteric artery was performed successfully .
the pathological diagnosis was multiple adenocarcinomas arising in villotubular adenomas ( t3n0m0 , stage iia ) ( fig .
he began to take sips of water on the third day after the operation , and the next day , he ate a soft meal without any problems .
he was discharged on the seventh day after the operation with a full recovery ( na , 141 mmol / l ; k , 3.4 mmol / l ; bun , 20 mg / dl ; cr , 1.0 mg / dl ) . during a follow - up at 9 months ,
the last serum careinoembryonal antigen and carbohydrate antigen 19 - 9 levels were 0.5 ng / ml and 5.6 u / ml .
his family history did not have any specific details but we urged other family members to receive endoscopy due to the early onset of his symptoms .
villous adenomas of the colon that cause secretory diarrhea were first described by mckittrick and wheelock in 1954 . it is a very rare but known complication of villous adenoma , which was described for the first time 50 years ago .
reaching the right diagnosis is not always as easy as in this case , and a complete colonoscopy is always mandatory .
therefore , in the case of a triad of prerenal failure , electrolyte disorder , and chronic diarrhea , the existence of an intestinal adenoma should always be considered . about 3% of villous adenomas
have secretory activity , and secretory villous adenomas associated with depletion syndrome are large , ranging from 7 to 18 cm at their greatest dimension .
they are situated primarily in the rectum and occasionally in the sigmoid colon , as in the present case .
the large size allows more surface area for secretion , and the distal location of these lesions means a minimal area of normal colonic mucosa remains to allow fluid absorption , resulting in depletion syndrome . it is unclear whether secretory villous adenomas occur in the proximal colon without depletion syndrome .
it is certainly possible since goblet cells are equally distributed throughout the colon . in a review of the literature on possible mechanisms of fluid and electrolyte imbalances , the electrolyte composition of mucin secreted by abnormal cells within the causative lesion
whereas a normal bowel absorbs sodium and water and secretes potassium , segments of intestine affected by villous adenoma have been found to secrete water , sodium , and potassium .
rectal effluent from a patient with villous adenoma of the rectum demonstrated prostaglandin e2 ( pge2 ) levels that were 3 to 6 times higher than normal .
mucosa adjacent to adenomatous polyps has been found to be unaffected by this , but adenoma - associated mucosa was demonstrated to synthesize larger amounts of pge2 .
nonreversible cyclooxygenase - inhibiting agents have been used to reduce pge2 production and consequently the loss of sodium and water through the rectum .
. however , the malignant potential of villous adenomas is well - recognized , with an incidence of carcinomatous change having been reported as high as 90% .
therefore , surgical removal is the only satisfactory treatment both to stop fluid and electrolyte loss and to prevent carcinoma formation .
endoscopic resection is presently considered the treatment of choice for adenoma . however , especially in mckittrick - wheelock syndrome , it is not always effective owing to an unfavorable location or extension of the tumor .
moreover , large colonic polyps that are unresectable during colonoscopy are associated with a high rate of unsuspected cancer . in a study by pokala et al . , postoperative histopathology reports after laparoscopic resection for endoscopically unresectable polyps revealed adenocarcinomas with an initial benign histology in up to 20% of cases .
reported a cancer risk for adenomas larger than 2.5 cm of the colon and rectum of 34% and 51% , respectively . in view of this high incidence of carcinoma in large polyps ,
a formal oncologic segmental colectomy is the most appropriate treatment of mckittrick - wheelock syndrome , and laparoscopic approach could be a feasible option in such cases . in conclusion , mckittrick - wheelock syndrome
early diagnosis is essential to commence the appropriate symptomatic therapy directed towards life - threatening electrolyte disturbances , and causal treatment can be undertaken .
mckittrick - wheelock syndrome is a disorder caused by fluid and electrolyte hypersecretion from a colorectal tumor . to present the case of a patient with a giant rectal villous tumor with mckittrick - wheelock syndrome who was successfully treated with laparoscopic surgery . 
 the case of a 59-year - old man who came to the emergency department with syncope , prerenal azotemia , and electrolyte disturbances with a background of chronic diarrhea is reported . 
 his condition was the result of fluid and electrolyte hypersecretion caused by rectal villotubular adenomas . 
 laparoscopic low anterior resection and subsequent volume and electrolyte replacement therapy resulted in complete recovery . 
 a microscopic examination revealed multiple , well - differentiated adenocarcinomas arising in villotubular adenomas . 
 laparoscopic surgical resection is a feasible therapeutic modality for mckittrick - wheelock syndrome .