medical_specialty amoebiasis
A liver abscess is a pus - filled mass inside the liver . Common causes are abdominal infections such as appendicitis or diverticulitis due to haematogenous spread through the portal vein . Rotavirus is the most common cause of diarrhoeal disease among infants and young children . It is a genus of double - stranded RNA viruses in the family " Reoviridae ". Nearly every child in the world is infected with rotavirus at least once by the age of five . Immunity develops with each ___MASK10___ , so subsequent infections are less severe ; adults are rarely affected . There are eight species of this virus , referred to as A , B , C , D , E , F , G and H . " Rotavirus A ", the most common species , causes more than 90 % of rotavirus infections in humans . Diarrhea , also spelled diarrhoea , is the condition of having at least three loose or liquid bowel movements each day . It often lasts for a few days and can result in dehydration due to fluid loss . Signs of dehydration often begin with loss of the normal stretchiness of the skin and irritable behaviour . This can progress to decreased urination , loss of skin color , a fast heart rate , and a decrease in responsiveness as it becomes more severe . Loose but non - watery stools in babies who are breastfed , however , may be normal . The most common cause is an ___MASK10___ of the intestines due to either a virus , bacteria , or parasite ; a condition known as gastroenteritis . These infections are often acquired from food or water that has been contaminated by stool , or directly from another person who is infected . It may be divided into three types : short duration watery diarrhea , short duration bloody diarrhea , and if it lasts for more than two weeks , persistent diarrhea . The short duration watery diarrhea may be due to an ___MASK10___ by cholera , although this is rare in the developed world . If blood is present it is also known as dysentery . A number of non - infectious causes may also result in diarrhea , including hyperthyroidism , lactose intolerance , inflammatory bowel disease , a number of medications , and irritable bowel syndrome . In most cases , stool cultures are not required to confirm the exact cause . Prevention of infectious diarrhea is by improved sanitation , clean drinking water , and hand washing with soap . Breastfeeding for at least six months is also recommended as is vaccination against rotavirus . Oral rehydration solution ( ORS ), which is clean water with modest amounts of salts and sugar , is the treatment of choice . Zinc tablets are also recommended . These treatments have been estimated to have saved 50 million children in the past 25 years . When people have diarrhea it is recommended that they continue to eat healthy food and babies continue to be breastfed . If commercial ORS are not available , homemade solutions may be used . In those with severe dehydration , intravenous fluids may be required . Most cases ; however , can be managed well with fluids by mouth . Antibiotics , while rarely used , may be recommended in a few cases such as those who have bloody diarrhea and a high fever , those with severe diarrhea following travelling , and those who grow specific bacteria or parasites in their stool . Loperamide may help decrease the number of bowel movements but is not recommended in those with severe disease . About 1 . 7 to 5 billion cases of diarrhea occur per year . It is most common in developing countries , where young children get diarrhea on average three times a year . Total deaths from diarrhea are estimated at 1 . 26 million in 2013  down from 2 . 58 million in 1990 . In 2012 , it was the second most common cause of deaths in children younger than five ( 0 . 76 million or 11 %). Frequent episodes of diarrhea are also a common cause of malnutrition and the most common cause in those younger than five years of age . Other long term problems that can result include stunted growth and poor intellectual development . Cholera is an ___MASK10___ of the small intestine by some strains of the bacterium " Vibrio cholerae ". Symptoms may range from none , to mild , to severe . The classic symptom is large amounts of watery diarrhea that lasts a few days . Vomiting and muscle cramps may also occur . Diarrhea can be so severe that it leads within hours to severe dehydration and electrolyte imbalance . This may result in sunken eyes , cold skin , decreased skin elasticity , and wrinkling of the hands and feet . The dehydration may result in the skin turning bluish . Symptoms start two hours to five days after exposure . Cholera is caused by a number of types of " Vibrio cholerae ", with some types producing more severe disease than others . It is spread mostly by unsafe water and unsafe food that has been contaminated with human feces containing the bacteria . Undercooked seafood is a common source . Humans are the only animal affected . Risk factors for the disease include poor sanitation , not enough clean drinking water , and poverty . There are concerns that rising sea levels will increase rates of disease . Cholera can be diagnosed by a stool test . A rapid dipstick test is available but is not as accurate . Prevention involves improved sanitation and access to clean water . Cholera vaccines that are given by mouth provide reasonable protection for about six months . They have the added benefit of protecting against another type of diarrhea caused by " E . coli ". The primary treatment is oral rehydration therapy  the replacement of fluids with slightly sweet and salty solutions . Rice - based solutions are preferred . Zinc supplementation is useful in children . In severe cases , intravenous fluids , such as Ringer ' s lactate , may be required , and antibiotics may be beneficial . Testing to see which antibiotic the cholera is susceptible to can help guide the choice . Cholera affects an estimated 3  5 million people worldwide and causes 58 , 000  130 , 000 deaths a year as of 2010 . While it is currently classified as a pandemic , it is rare in the developed world . Children are mostly affected . Cholera occurs as both outbreaks and chronically in certain areas . Areas with an ongoing risk of disease include Africa and south - east Asia . While the risk of death among those affected is usually less than 5 %, it may be as high as 50 % among some groups who do not have access to treatment . Historical descriptions of cholera are found as early as the 5th century BC in Sanskrit . The study of cholera by John Snow between 1849 and 1854 led to significant advances in the field of epidemiology . Irritable bowel syndrome ( IBS ) is a group of symptoms  including abdominal pain and changes in the pattern of bowel movements without any evidence of underlying damage . These symptoms occur over a long time , often years . It has been classified into four main types depending on if diarrhea is common , constipation is common , both are common , or neither occurs very often ( IBS - D , IBS - C , IBS - M , or IBS - U respectively ). IBS negatively affects quality of life and may result in missed school or work . Disorders such as anxiety , major depression , and chronic fatigue syndrome are common among people with IBS . The causes of IBS are not clear . Theories include gut  brain axis problems , small intestinal bacterial overgrowth , genetic factors , food sensitivity , and gut motility problems . Onset may be triggered by an intestinal ___MASK10___ , or stressful life event . IBS is a functional gastrointestinal disorder . Diagnosis is based on signs and symptoms in the absence of worrisome features . Worrisome features include onset at greater than 50 years of age , weight loss , blood in the stool , or a family history of inflammatory bowel disease . Other conditions that may present similarly include celiac disease , microscopic colitis , inflammatory bowel disease , bile acid malabsorption , and colon cancer . There is no cure for IBS . Treatment is carried out to improve symptoms . This may including dietary changes , medication , probiotics , and counseling . Dietary measures include increasing soluble fiber intake , a gluten free diet , or a diet low in fermentable oligosaccharides , disaccharides , monosaccharides , and polyols ( FODMAP ). The medication loperamide may be used to help with diarrhea while laxatives may be used to help with constipation . Antidepressants may improve overall symptoms and pain . Patient education and a good doctor  patient relationship are an important part of care . About 10 to 15 % of people in the developed world are believed to be affected by IBS . It is more common in South America and less common in Southeast Asia . It is twice as common in women as men and typically occurs before age 45 . The condition appears to become less common with age . IBS does not affect life expectancy or lead to other serious diseases . The first description of the condition was in 1820 while the current term " irritable bowel syndrome " came into use in 1944 . Classification . IBS can be classified as either diarrhea - predominant ( IBS - D ), constipation - predominant ( IBS - C ), or with alternating stool pattern ( IBS - A ) or pain - predominant . In some individuals , IBS may have an acute onset and develop after an infectious illness characterized by two or more of : fever , vomiting , diarrhea , or positive stool culture . This postinfective syndrome has consequently been termed " postinfectious IBS " ( IBS - PI ). Influenza , commonly known as " the flu ", is an ___MASK9___ caused by an influenza virus . Symptoms can be mild to severe . The most common symptoms include : a high fever , runny nose , sore throat , muscle pains , headache , coughing , and feeling tired . These symptoms typically begin two days after exposure to the virus and most last less than a week . The cough , however , may last for more than two weeks . In children , there may be nausea and vomiting , but these are not common in adults . Nausea and vomiting occur more commonly in the unrelated infection gastroenteritis , which is sometimes inaccurately referred to as " stomach flu " or " 24 - hour flu ". Complications of influenza may include viral pneumonia , secondary bacterial pneumonia , sinus infections , and worsening of previous health problems such as asthma or heart failure . Three types of influenza viruses affect people , called Type A , Type B , and Type C . Usually , the virus is spread through the air from coughs or sneezes . This is believed to occur mostly over relatively short distances . It can also be spread by touching surfaces contaminated by the virus and then touching the mouth or eyes . A person may be infectious to others both before and during the time they are showing symptoms . The infection may be confirmed by testing the throat , sputum , or nose for the virus . A number of rapid tests are available ; however , people may still have the infection if the results are negative . A type of polymerase chain reaction that detects the virus ' s RNA is more accurate . Frequent hand washing reduces the risk of infection because the virus is inactivated by soap . Wearing a surgical mask is also useful . Yearly vaccinations against influenza are recommended by the World Health Organization for those at high risk . The vaccine is usually effective against three or four types of influenza . It is usually well tolerated . A vaccine made for one year may not be useful in the following year , since the virus evolves rapidly . Antiviral drugs such as the neuraminidase inhibitor oseltamivir , among others , have been used to treat influenza . Their benefits in those who are otherwise healthy do not appear to be greater than their risks . No benefit has been found in those with other health problems . Influenza spreads around the world in a yearly outbreak , resulting in about three to five million cases of severe illness and about 250 , 000 to 500 , 000 deaths . In the Northern and Southern parts of the world outbreaks occur mainly in winter while in areas around the equator outbreaks may occur at any time of the year . Death occurs mostly in the young , the old and those with other health problems . Larger outbreaks known as pandemics are less frequent . In the 20th century three influenza pandemics occurred : Spanish influenza in 1918 , Asian influenza in 1958 , and Hong Kong influenza in 1968 , each resulting in more than a million deaths . The World Health Organization declared an outbreak of a new type of influenza A / H1N1 to be a pandemic in June 2009 . Influenza may also affect other animals , including pigs , horses and birds . Malaria is a mosquito - borne ___MASK9___ affecting humans and other animals caused by parasitic protozoans ( a group of single - celled microorganisms ) belonging to the " Plasmodium " type . Malaria causes symptoms that typically include fever , fatigue , vomiting , and headaches . In severe cases it can cause yellow skin , seizures , coma , or death . Symptoms usually begin ten to fifteen days after being bitten . If not properly treated , people may have recurrences of the disease months later . In those who have recently survived an infection , reinfection usually causes milder symptoms . This partial resistance disappears over months to years if the person has no continuing exposure to malaria . The disease is most commonly transmitted by an infected female " Anopheles " mosquito . The mosquito bite introduces the parasites from the mosquito ' s saliva into a person ' s blood . The parasites travel to the liver where they mature and reproduce . Five species of " Plasmodium " can infect and be spread by humans . Most deaths are caused by " P . falciparum " because " P . vivax ", " P . ovale ", and " P . malariae " generally cause a milder form of malaria . The species " P . knowlesi " rarely causes disease in humans . Malaria is typically diagnosed by the microscopic examination of blood using blood films , or with antigen - based rapid diagnostic tests . Methods that use the polymerase chain reaction to detect the parasite ' s DNA have been developed , but are not widely used in areas where malaria is common due to their cost and complexity . The risk of disease can be reduced by preventing mosquito bites through the use of mosquito nets and insect repellents , or with mosquito control measures such as spraying insecticides and draining standing water . Several medications are available to prevent malaria in travellers to areas where the disease is common . Occasional doses of the combination medication sulfadoxine / pyrimethamine are recommended in infants and after the first trimester of pregnancy in areas with high rates of malaria . Despite a need , no effective vaccine exists , although efforts to develop one are ongoing . The recommended treatment for malaria is a combination of antimalarial medications that includes an artemisinin . The second medication may be either mefloquine , lumefantrine , or sulfadoxine / pyrimethamine . Quinine along with doxycycline may be used if an artemisinin is not available . It is recommended that in areas where the disease is common , malaria is confirmed if possible before treatment is started due to concerns of increasing drug resistance . Resistance among the parasites has developed to several antimalarial medications ; for example , chloroquine - resistant " P . falciparum " has spread to most malarial areas , and resistance to artemisinin has become a problem in some parts of Southeast Asia . The disease is widespread in the tropical and subtropical regions that exist in a broad band around the equator . This includes much of Sub - Saharan Africa , Asia , and Latin America . In 2015 , there were 214 million cases of malaria worldwide resulting in an estimated 438 , 000 deaths , 90 % of which occurred in Africa . Rates of disease have decreased from 2000 to 2015 by 37 %, but increased from 2014 during which there were 198 million cases . Malaria is commonly associated with poverty and has a major negative effect on economic development . In Africa , it is estimated to result in losses of US $ 12 billion a year due to increased healthcare costs , lost ability to work , and negative effects on tourism . Giardia lamblia , also known as Giardia intestinalis , is a flagellated parasite that colonizes and reproduces in the small intestine , causing giardiasis . The parasite attaches to the epithelium by a ventral adhesive disc , and reproduces via binary fission . Giardiasis does not spread via the bloodstream , nor does it spread to other parts of the gastrointestinal tract , but remains confined to the lumen of the small intestine . " Giardia " trophozoites absorb their nutrients from the lumen of the small intestine , and are anaerobes . If the organism is split and stained , its characteristic pattern resembles the familiar " smiley face " symbol . Chief pathways of human ___MASK10___ include ingestion of untreated sewage , a phenomenon particularly common in many developing countries ; contamination of natural waters also occurs in watersheds where intensive grazing occurs . Diverticulitis is a digestive disease in which pouches within the large bowel wall become inflamed . Symptoms typically include lower abdominal pain of a sudden onset . Onset however may also occur over a few days . In North America and Europe pain is usually on the left side , while in Asia it is often on the right . There may also be fever , nausea , diarrhea or constipation , or blood in the stool . Repeated attacks may occur . The cause is uncertain . Risk factors may include obesity , lack of exercise , smoking , a family history of the disease , and nonsteroidal anti - inflammatory drugs ( NSAIDs ). The role of dietary fibre is unclear . Having pouches in the large intestine that are not inflamed is known as diverticulosis . Inflammation occurs in between 10 % and 25 % at some point in time and is due to a bacterial ___MASK10___ . Diagnosis may be made by blood tests , CT scan , colonoscopy , or lower gastrointestinal series . The differential diagnosis includes irritable bowel syndrome . While avoiding nuts and seeds has historically been recommended , an association between eating these foods and diverticulitis has not been found , and therefore , avoiding these foods is no longer recommended . Mesalazine and rifaximin appear useful for preventing attacks in those with diverticulosis . For mild diverticulitis , antibiotics by mouth and a liquid diet is recommended . For severe cases intravenous antibiotics , hospital admission , and complete bowel rest may be recommended . Probiotics are of unclear use . Complications such as abscess formation , fistula formation , and perforation of the colon may require ___MASK85___ . The disease is common in the Western world and uncommon in Africa and Asia . In the Western world about 35 % of people have diverticulosis while it affects less than 1 % of those in rural Africa . The disease becomes more frequent with age being particularly common in those over the age of 50 . It has also become more common in all parts of the world . In 2003 in Europe it resulted in about 13 , 000 deaths . Costs associated with diverticular disease are around $ 2 . 4 billion a year in the United States as of 2013 . Signs and symptoms . People typically have left lower quadrant abdominal pain of sudden onset . There may also be fever , nausea , diarrhea or constipation , and there may be blood in the stool . Peritonitis is an inflammation of the peritoneum , the thin tissue that lines the inner wall of the abdomen and covers most of the abdominal organs . Peritonitis may be localized or generalized , and may result from ___MASK10___ ( often due to perforation of the intestinal tract as may occur in abdominal trauma or inflamed appendix ) or from a non - infectious process . Nitazoxanide is a broad - spectrum antiparasitic and broad - spectrum antiviral drug that is used in medicine for the treatment of various helminthic , protozoal , and viral infections . It is indicated for the treatment of ___MASK10___ by " Cryptosporidium parvum " and " Giardia lamblia " in immunocompetent individuals and has been repurposed for the treatment of influenza . Nitazoxanide has also been shown to have " in vitro " antiparasitic activity and clinical treatment efficacy for infections caused by other protozoa and helminths ; emerging evidence suggests that it possesses efficacy in treating a number of viral infections as well . Malnutrition or malnourishment is a condition that results from eating a diet in which nutrients are either not enough or are too much such that the diet causes health problems . It may involve calories , protein , carbohydrates , vitamins or minerals . Not enough nutrients is called undernutrition or undernourishment while too much is called overnutrition . Malnutrition is often used specifically to refer to undernutrition where there is not enough calories , protein , or micronutrients . If undernutrition occurs during pregnancy , or before two years of age , it may result in permanent problems with physical and mental development . Extreme undernourishment , known as starvation , may have symptoms that include : a short height , thin body , very poor energy levels , and swollen legs and abdomen . People also often get infections and are frequently cold . The symptoms of micronutrient deficiencies depend on the micronutrient that is lacking . Undernourishment is most often due to not enough high - quality food being available to eat . This is often related to high food prices and poverty . A lack of breastfeeding may contribute , as may a number of infectious diseases such as : gastroenteritis , pneumonia , malaria , and measles , which increase nutrient requirements . There are two main types of undernutrition : protein - energy malnutrition and dietary deficiencies . Protein - energy malnutrition has two severe forms : marasmus ( a lack of protein and calories ) and kwashiorkor ( a lack of just protein ). Common micronutrient deficiencies include : a lack of iron , iodine , and vitamin A . During pregnancy , due to the body ' s increased need , deficiencies may become more common . In some developing countries , overnutrition in the form of obesity is beginning to present within the same communities as undernutrition . Other causes of malnutrition include anorexia nervosa and bariatric ___MASK85___ . Efforts to improve nutrition are some of the most effective forms of development aid . Breastfeeding can reduce rates of malnutrition and death in children , and efforts to promote the practice increase the rates of breastfeeding . In young children , providing food ( in addition to breastmilk ) between six months and two years of age improves outcomes . There is also good evidence supporting the supplementation of a number of micronutrients to women during pregnancy and among young children in the developing world . To get food to people who need it most , both delivering food and providing money so people can buy food within local markets are effective . Simply feeding students at school is insufficient . Management of severe malnutrition within the person ' s home with ready - to - use therapeutic foods is possible much of the time . In those who have severe malnutrition complicated by other health problems , treatment in a hospital setting is recommended . This often involves managing low blood sugar and body temperature , addressing dehydration , and gradual feeding . Routine antibiotics are usually recommended due to the high risk of infection . Longer - term measures include : improving agricultural practices , reducing poverty , improving sanitation , and the empowerment of women . There were 793 million undernourished people in the world in 2015 ( 13 % of the total population ). This is a reduction of 216 million people since 1990 when 23 % were undernourished . In 2012 it was estimated that another billion people had a lack of vitamins and minerals . In 2013 , protein - energy malnutrition was estimated to have resulted in 469 , 000 deaths  down from 510 , 000 deaths in 1990 . Other nutritional deficiencies , which include iodine deficiency and iron deficiency anemia , result in another 84 , 000 deaths . In 2010 , malnutrition was the cause of 1 . 4 % of all disability adjusted life years . About a third of deaths in children are believed to be due to undernutrition , although the deaths are rarely labelled as such . In 2010 , it was estimated to have contributed to about 1 . 5 million deaths in women and children , though some estimate the number may be greater than 3 million . An additional 165 million children were estimated to have stunted growth from malnutrition in 2013 . Undernutrition is more common in developing countries . Certain groups have higher rates of undernutrition , including women  in particular while pregnant or breastfeeding  children under five years of age , and the elderly . In the elderly , undernutrition becomes more common due to physical , psychological , and social factors . Hyperthyroidism is the condition that occurs due to excessive production of thyroid hormone by the thyroid gland . Thyrotoxicosis is the condition that occurs due to excessive thyroid hormone of any cause and therefore includes hyperthyroidism . Some , however , use the terms interchangeably . Signs and symptoms vary between people and may include irritability , muscle weakness , sleeping problems , a fast heartbeat , heat intolerance , diarrhea , enlargement of the thyroid , and weight loss . Symptoms are typically less in the old and during pregnancy . An uncommon complication is thyroid storm in which an event such as an ___MASK10___ results in worsening symptoms such as confusion and a high temperature and often results in death . The opposite is hypothyroidism , when the thyroid gland does not make enough thyroid hormone . Graves ' disease is the cause of about 50 % to 80 % of the cases of hyperthyroidism in the United States . Other causes include multinodular goiter , toxic adenoma , inflammation of the thyroid , eating too much iodine , and too much synthetic thyroid hormone . A less common cause is a pituitary adenoma . The diagnosis may be suspected based on signs and symptoms and then confirmed with blood tests . Typically blood tests show a low thyroid stimulating hormone ( TSH ) and raised T or T . Radioiodine uptake by the thyroid , thyroid scan , and TSI antibodies may help determine the cause . Treatment depends partly on the cause and severity of disease . There are three main treatment options : radioiodine therapy , medications , and thyroid ___MASK85___ . Radioiodine therapy involves taking iodine - 131 by mouth which is then concentrated in and destroys the thyroid over weeks to months . The resulting hypothyroidism is treated with synthetic thyroid hormone . Medications such as beta blockers may control the symptoms , and anti - thyroid medications such as methimazole may temporarily help people while other treatments are having effect . ___MASK85___ to remove the thyroid is another option . This may be used in those with very large thyroids or when cancer is a concern . In the United States hyperthyroidism affects about 1 . 2 % of the population . It occurs between two and ten times more often in women . Onset is commonly between 20 and 50 years of age . Overall the disease is more common in those over the age of 60 years . Amoebiasis , also known as amebiasis or entamoebiasis , is an ___MASK10___ caused by any of the amoebas of the Entamoeba group . Symptoms are most common upon ___MASK10___ by Entamoeba histolytica . Amoebiasis can present with no , mild , or severe symptoms . Symptoms may include abdominal pain , mild diarrhoea , bloody diarrhea or severe colitis with tissue death and perforation . This last complication may cause peritonitis . People affected may develop anemia due to loss of blood . Invasion of the intestinal lining causes amoebic bloody diarrhea or amoebic colitis . If the parasite reaches the bloodstream it can spread through the body , most frequently ending up in the liver where it causes amoebic liver abscesses . Liver abscesses can occur without previous diarrhea . Cysts of Entamoeba can survive for up to a month in soil or for up to 45 minutes under fingernails . It is important to differentiate between amoebiasis and bacterial colitis . The preferred diagnostic method it through faecal examination under microscope , but requires a skilled microscopist and may not be reliable when excluding ___MASK10___ . Increased white blood cell count is present in severe cases , but not in mild ones . The most accurate test is for antibodies in the blood , but it may remain positive following treatment . Prevention of amoebiasis is by separating food and water from faeces and by proper sanitation measures . There is no vaccine . There are two treatment options depending on the location of the ___MASK10___ . Amoebiasis in tissues is treated with either metronidazole , tinidazole , nitazoxanide , dehydroemetine or chloroquine , while luminal ___MASK10___ is treated with diloxanide furoate or iodoquinoline . For treatment to be effective against all stages of the amoeba may require a combination of medications . Infections without symptoms do not require treatment but infected individuals can spread the parasite to others and treatment can be considered . Treatment of other entamoeba infections apart from E . histolytica is not needed . Amoebiasis is present all over the world . About 480 million people are infected with E . histiolytica and this results in the death of between 40 , 000 -- 110 , 000 people every year . E . dispar is more common in certain areas and symptomatic cases may be fewer than previously reported . The first case of amoebiasis was documented in 1875 and in 1891 E . histiolytica was identified resulting in the terms amoebic dysentery and amoebic liver abscess . Further evidence from the Philippines in 1913 found that upon ingesting cysts of E . histiolytica volunteers developed the disease . It has been known since 1903 that at least one species of non - disease causing entamoeba exist , but it was first formally recognized by the WHO in 1997 . In addition to the recognized E . dispar evidence shows there is likely another species of E . moshkovskii as well . The reason these species have n ' t been differentiated until recently may be because they look very similar . ___MASK10___ is the invasion of an organism ' s body tissues by disease - causing agents , their multiplication , and the reaction of host tissues to these organisms and the toxins they produce . ___MASK9___ , also known as transmissible disease or communicable disease , is illness resulting from an infection . Infections are caused by infectious agents including viruses , viroids , prions , bacteria , nematodes such as parasitic roundworms and pinworms , arthropods such as ticks , mites , fleas , and lice , fungi such as ringworm , and other macroparasites such as tapeworms and other helminths . Appendicitis is inflammation of the appendix . Symptoms commonly include right lower abdominal pain , nausea , vomiting , and decreased appetite . However , approximately 40 % of people do not have these typical symptoms . Severe complications of a ruptured appendix include widespread , painful inflammation of the inner lining of the abdominal wall and sepsis . Appendicitis is caused by a blockage of the hollow portion of the appendix . This is most commonly due to a calcified " stone " made of feces . Inflamed lymphoid tissue from a viral ___MASK10___ , parasites , gallstone , or tumors may also cause the blockage . This blockage leads to increased pressures in the appendix , decreased blood flow to the tissues of the appendix , and bacterial growth inside the appendix causing inflammation . The combination of inflammation , reduced blood flow to the appendix and distention of the appendix causes tissue injury and tissue death . If this process is left untreated , the appendix may burst , releasing bacteria into the abdominal cavity , leading to severe abdominal pain and increased complications . The diagnosis of appendicitis is largely based on the person ' s signs and symptoms . In cases where the diagnosis cannot be made based on the person ' s history and physical exam , close observation , radiographic imaging and laboratory tests can be helpful . The two most common imaging tests used are an ultrasound and computed tomography ( CT scan ). CT scan has been shown to be more accurate than ultrasound in detecting acute appendicitis . However , ultrasound may be preferred as the first imaging test in children and pregnant women because of the risks associated with radiation exposure from CT scans . The standard treatment for acute appendicitis is surgical removal of the appendix . This may be done by an open incision in the abdomen ( laparotomy ) or through a few smaller incisions with the help of cameras ( laparoscopy ). ___MASK85___ decreases the risk of side effects or death associated with rupture of the appendix . Antibiotics may be equally effective in certain cases of non - ruptured appendicitis . It is one of the most common and significant causes of severe abdominal pain that comes on quickly worldwide . In 2013 about 16 million cases of appendicitis occurred . This resulted in 72 , 000 deaths globally . In the United States , appendicitis is the most common cause of acute abdominal pain requiring ___MASK85___ . Each year in the United States , more than 300 , 000 people with appendicitis have their appendix surgically removed . Reginald Fitz is credited with being the first person to describe the condition in 1886 . Lactose intolerance is a condition in which people have symptoms due to the decreased ability to digest lactose , a sugar found in milk products . Those affected vary in the amount of lactose they can tolerate before symptoms develop . Symptoms may include abdominal pain , bloating , diarrhea , gas , and nausea . These typically start between half and two hours after drinking milk or eating milk products . Severity depends on the amount a person eats or drinks . It does not cause damage to the gastrointestinal tract . Lactose intolerance is due to not enough of the enzyme lactase in the small intestines to break lactose down into glucose and galactose . There are four types : primary , secondary , developmental , and congenital . Primary lactose intolerance is when the amount of lactase decline as people age . Secondary lactose intolerance is due to injury to the small intestine such as from ___MASK10___ , celiac disease , inflammatory bowel disease , or other diseases . Developmental lactose intolerance may occur in premature babies and usually improves over a short period of time . Congenital lactose intolerance is an extremely rare genetic disorder in which little or no lactase is made from birth . Diagnosis may be confirmed if symptoms resolve following eliminating lactose from the diet . Other supporting tests include a hydrogen breath test and a stool acidity test . Other conditions that may produce similar symptoms include irritable bowel syndrome , celiac disease , and inflammatory bowel disease . Lactose intolerance is different from a milk allergy . Management is typically by decreasing the amount of lactose in the diet or taking lactase supplements . Those affected are usually able to drink at least one cup of milk without developing significant symptoms , with greater amounts tolerated if drunk with a meal or throughout the day . The number of people with lactose intolerance is unknown . The percentage of the population that has a decrease in lactase as they age is less than 10 % in Northern Europe and as high as 95 % in parts of Asia and Africa . Onset is typically in late childhood or adulthood . The ability to digest lactose into adulthood is believed to have developed among some human populations in the last 10 , 000 years . Anemia , also spelled anaemia , is usually defined as a decrease in the total amount of red blood cells ( RBCs ) or hemoglobin in the blood . It can also be defined as a lowered ability of the blood to carry oxygen . When anemia comes on slowly , the symptoms are often vague and may include feeling tired , weakness , shortness of breath or a poor ability to exercise . Anemia that comes on quickly often has greater symptoms , which may include confusion , feeling like one is going to pass out , loss of consciousness , or increased thirst . Anemia must be significant before a person becomes noticeably pale . Additional symptoms may occur depending on the underlying cause . There are three main types of anemia : that due to blood loss , that due to decreased red blood cell production and that due to increased red blood cell breakdown . Causes of blood loss include trauma and gastrointestinal bleeding , among others . Causes of decreased production include iron deficiency , a lack of vitamin B12 , thalassemia , and a number of neoplasms of the bone marrow . Causes of increased breakdown include a number of genetic conditions such as sickle cell anemia , infections like malaria , and certain autoimmune diseases . It can also be classified based on the size of red blood cells and amount of hemoglobin in each cell . If the cells are small , it is microcytic anemia . If they are large , it is macrocytic anemia while if they are normal sized , it is normocytic anemia . Diagnosis in men is based on a hemoglobin of less than 130 to 140 g / L ( 13 to 14 g / dL ), while in women , it must be less than 120 to 130 g / L ( 12 to 13 g / dL ), Further testing is then required to determine the cause . Certain groups of individuals , such as pregnant women , benefit from the use of iron pills for prevention . Dietary supplementation , without determining the specific cause , is not recommended . The use of blood transfusions is typically based on a person ' s signs and symptoms . In those without symptoms , they are not recommended unless hemoglobin levels are less than 60 to 80 g / L ( 6 to 8 g / dL ). These recommendations may also apply to some people with acute bleeding . Erythropoiesis - stimulating medications are only recommended in those with severe anemia . Anemia is the most common disorder of the blood , affecting about a quarter of the people globally . Iron - deficiency anemia affects nearly 1 billion . In 2013 , anemia due to iron deficiency resulted in about 183 , 000 deaths  down from 213 , 000 deaths in 1990 . It is more common in females than males , among children , during pregnancy , and in the elderly . Anemia increases costs of medical care and lowers a person ' s productivity through a decreased ability to work . The name is derived from "", meaning " lack of blood ", from  - " an -", " not " +  " haima ", " blood ".