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sunny2
Forum Elite Topics: 51 Posts: 373 |
2 year old boy who has been previously well presents with foamy diarrohea, vague upper abdominal discomfort and failure to thrive for 2 months. weight is on the 25 th percentile, stool test reveals steatorrhoea with fatty acid crystals ,the most likely diagnosis is : A. giardia lamblia B. coeliac disease C. cystic fibrosis D. campylobacter jejuni E. rotavirus infection F. cryptosporidia G. acute gasteroenteritis
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seri
| Forum Senior Topics: 4 Posts: 189
c
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chemamr
| Forum Hero  Topics: 340 Posts: 4448
C?
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sunny2
| Forum Elite Topics: 51 Posts: 373
are you sure chemamr or just putting a guess with keywords, because i took the same guess and was wrong, cystic fibrosis is not the answer, i'll explain why it is not but for the moment will let this question open for some more time 
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chemamr
| Forum Hero Topics: 340 Posts: 4448
well, i just read it once and as you said according to the keywords i thought it could be C. But it can be also Giardia, I guess. I'll wait for your answer with explanation.
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sunny2
| Forum Elite Topics: 51 Posts: 373
and why do you think it's Giardia and not coeliac diesase or any other choice
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chemamr
| Forum Hero Topics: 340 Posts: 4448
it can also be celiac disease, and maybe the child has just started to eat gluten in his/her diet. Cystic fibrosis usually starts in the 1st year but it can also start later. So, these 3 can be the answer. Giardia can also cause the signs/symptoms of this patient, more if this child is in a developing country which we don't know. Now, what do you think sunny2?
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sunny2
| Forum Elite Topics: 51 Posts: 373
chemamr, I think you did a pretty good job ! coeliac dis. is possible, but would usually have an earlier onset when glten is introduced into the diet from about 6 months. CF with significant malabsorption would present in early infancy, while campylobacter jejuni and rotavirus infections present as acute gasteroenteritis. giardia lamblia is very common in young children, particularly very common in day-care in US. chemamr , this is the explanation , it doesn't explain why specifically GL is the answer, is it just because of day care !!
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chemamr
| Forum Hero Topics: 340 Posts: 4448
thanks. ok.
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AAAAA
| Forum Fanatic Topics: 159 Posts: 2013
The answer is C. It can not be Celiac Sprue. Celiac Sprue is a malabsorption disease but does not present with foamy diarrhea. Foamy diarrhea is due to the fat in the stool. The entire question points to fat malabsorption and Celiac Disease is not a fat malabsorption disease. Giardia causes chronic diarrhea but also not foamy diarrhea. It is a watery diarrhea !!!
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AAAAA
| Forum Fanatic Topics: 159 Posts: 2013
fibrosis From Wikipedia, the free encyclopedia Jump to: navigation, search Cystic Fibrosis ICD-10 E84 ICD-9 277 Cystic fibrosis, (CF) is a common hereditary human disease which affects many different parts of the body, including the lungs, pancreas, gastrointestinal tract, reproductive organs, and sinuses. Individuals with cystic fibrosis are typically diagnosed prior to birth by genetic testing or in early childhood by a sweat test. In early childhood, prominent symptoms include growth problems or frequent infections, especially of the lung. As the disease progresses, frequent lung infections (pneumonia) often lead to breathing problems, lung damage, prolonged courses of antibiotics, and respiratory failure requiring support by a ventilator. CF can also lead to frequent sinus infections, diabetes mellitus, difficulty with digestion, and infertility. Currently, most individuals with cystic fibrosis die young — many in their 20s and 30s from lung failure. CF is caused by a mutation in a gene called the cystic fibrosis transmembrane conductance regulator (CFTR) which helps create sweat, digestive juices, and mucus. Although most people without CF have two working copies of the CFTR gene, only one gene is needed to prevent cystic fibrosis. CF develops when neither gene works normally. The CFTR gene is therefore a recessive gene and, because both men and women can develop cystic fibrosis, CF is known as an autosomal recessive disease. The name cystic fibrosis comes from the characteristic scarring (fibrosis) and cyst formation within the pancreas, first recognized in the 1930s.[1] CF is most common among Caucasians and Ashkenazi Jews; one in 25 people of European descent carry one gene for CF. Approximately 30,000 Americans have CF, making it one of the most common fatal inherited diseases. Cystic fibrosis does not currently have a cure. The lung disease is often treated with antibiotics, bronchodilators, physical therapy, nebulized saline, and medication to help break down mucus. Ultimately, lung transplantation or combined lung and pancreas transplantation may be necessary. Diabetes is treated with insulin and sinus infections require antibiotics and often surgery. Problems with digestion are overcome by replacing missing digestive enzymes, supplementing poorly absorbed vitamins, and increasing portion size. Contents[hide] 1 Symptoms and signs 1.1 Lung and sinus disease 1.2 Gastrointestinal, liver and pancreatic disease 1.3 Endocrine disease and growth 1.4 Infertility 2 Diagnosis 3 Pathophysiology 3.1 The role of chronic infection in lung disease 3.2 Molecular biology 4 Treatment 4.1 Antibiotics to treat lung disease 4.2 Other methods to treat lung disease 4.3 Treatment of other aspects of CF 4.4 Transplantation and gene therapy 5 Epidemiology 6 Theories about the prevalence of CF 7 History 8 See also 9 References 10 External links 10.1 General 10.2 Regional 10.3 Medical 10.4 Personal resources [edit] Symptoms and signs The symptoms of cystic fibrosis depend on the age of an individual, prior therapies, and the types of infections a person has experienced. Cystic fibrosis affects the entire body and impacts the fundamental processes of growth, breathing, digestion, and reproduction. The newborn period may be marked by poor weight gain and intestinal blockage caused by thick stool. Other symptoms of CF manifest during the remainder of childhood and early adulthood. These include continued problems with growth, the onset of lung disease, and increasing difficulties with poor absorption of vitamins and nutrients by the gastrointestinal tract. In addition, difficulties with fertility may become apparent when reproduction is attempted. [edit] Lung and sinus disease The most significant lung disease results from clogging of the smaller airways with the thick mucus caused by cystic fibrosis. Inflammation and infection cause injury to the lungs and structural changes which lead to a variety of symptoms. In the early stages, incessant coughing, copious sputum production, shortness of breath, and decreased ability to exercise are prominent symptoms. Many of these symptoms occur when bacteria which always live in the thick mucus grow out of control and cause pneumonia. In later stages of CF, changes in the architecture of the lung cause chronic difficulties breathing. Aspergillus fumigatus A common fungus which can lead to worsening lung disease in people with CF Other symptoms include coughing up blood, changes in the major airways in the lungs (bronchiectasis), high blood pressure in the lung (pulmonary hypertension), heart failure, difficulties getting enough oxygen to the body, and respiratory failure requiring support with breathing masks such as bilevel positive airway pressure machines or ventilators.[2] In addition to typical bacteria infections, people with CF are at increased risk for several other infectious and non-infectious lung disease. Among these are allergic bronchopulmonary aspergillosis, in which the body's response to the common fungus Aspergillus fumigatus causes worsening of breathing problems. Another common infection is with mycobacterium avium complex (MAC), a group of bacteria related to tuberculosis which can cause further lung damage and does not respond to common antibiotics. Mucus in the paranasal sinuses is equally thick and may also cause blockage of the sinus passages, leading to infection. This may lead to facial pain, fever, nasal drainage, and headaches. In addition, individuals with CF may develop overgrowth of the nasal tissue (nasal polyps) which can further lead to blockage and difficulty breathing through the nose.[3] [edit] Gastrointestinal, liver and pancreatic disease Prior to prenatal and newborn screening, cystic fibrosis was often diagnosed when a newborn infant failed to pass stool (meconium). Indeed, meconium may completely block the intestines and cause serious illness. This condition, called meconium ileus, occurs in 10% of newborns with CF.[4] In addition, protrusion of internal rectal membranes (rectal prolapse) is more common in CF because of increased stool volume, malnutrition, and increased intra–abdominal pressure due to coughing.[5] The thick mucus seen in the lung has its counterpart in thickened secretions from the pancreas, an organ responsible for providing digestive juices which help break down food. These secretions block the movement of the digestive enzymes into the gut and result in irreversible damage to the pancreas, often with painful inflammation (pancreatitis)[6]. The lack of digestive enzymes leads to difficulty absorbing nutrients with their subsequent excretion in the stool, a disorder known as malabsorption. Malabsorption leads to malnutrition and poor growth and development. In addition, individuals with CF have difficulties absorbing vitamins A, D, E, and K. In addition to the pancreas problems, people with cystic fibrosis experience more heartburn, intestinal blockage by intussusception, and have higher rates of constipation.[7] In fact, as people with CF age, they are at increased risk for distal intestinal obstruction syndrome, where thickened stool blocks the gut and causes bowel obstruction reminiscent of meconium ileus.[8] Thickened secretions also may cause liver problems in patients with CF. Bile secreted by the liver to aid in digestion may block the bile ducts within the liver, leading to liver damage. Over time, this can lead to cirrhosis, in which the liver fails to clean the blood of toxins and does not make important proteins such as those responsible for blood clotting.[9] [edit] Endocrine disease and growth Clubbing Patients with CF often have enlargement on their fingers, as shown here Pancreatic damage may lead to diabetes mellitus and vitamin D deficiency can lead to osteoporosis. The pancreas contains the islets of Langerhans which are responsible for making insulin, a hormone which helps regulate blood glucose. Damage of the pancreas can lead to loss of the islet cells, leading to diabetes.[10] Vitamin D is responsible for calcium and phosphorus regulation. Poor intake of vitamin D because of malabsorption leads to the bone disease osteoporosis in which weakened bones are more susceptible to fractures.[11] In addition, people with CF often develop clubbing of their fingers and toes due to chronic illness and low oxygen. Poor growth is a hallmark of CF. Children with CF typically do not gain weight or height at the same rate as their peers and occasionally are not diagnosed until investigation is initiated for poor growth. The causes of growth failure are multi–factorial and include chronic lung infection, poor absorption of nutrients through the gastrointestinal tract, and increased metabolic demand due to chronic illness. [edit] Infertility Infertility affects both men and women. At least 97% of men with cystic fibrosis are infertile.[12] These men make normal sperm but are missing the tube (vas deferens) which connects the testes to the ejaculatory ducts and from there the penis.[13] Likewise, a large percentage of men who are found to have congenital absence of the vas deferens during evaluation for infertility are found to have a mild, previously undiagnosed form of CF.[14] Whereas 20% of women with CF have difficulty conceiving, both because of thick cervical mucus and because of malnutrition leading to lack of periods (amenorrhea).[15] [edit] Diagnosis Cystic fibrosis may be diagnosed in a variety of ways. As of 2006 in the United States, ten percent of cases are diagnosed shortly after birth by blood testing done as part of newborn screening programs which looks for elevated amounts of the enzyme trypsin. However, most states and countries do not screen for CF routinely. Therefore, most individuals are diagnosed after symptoms prompt an evaluation for cystic fibrosis. The most commonly used form of testing is the sweat test. Sweat testing involves application of a medication which stimulates sweating (pilocarpine) to one electrode of an apparatus and running electric current to a separate electrode on the skin. This process, called iontophoresis, causes sweating; the sweat is then collected on filter paper and analyzed for abnormal amounts of sodium and chloride. People with CF have increased amounts of sodium and chloride in their sweat. CF can also be diagnosed by direct identification of mutations in the CFTR gene.[16] A multitude of tests are used to study individuals with CF with particular symptoms. X-rays and CAT scans are used to examine the lungs for signs of damage or infection. Examination of the sputum under a microscope is used to identify which particular bacteria are causing infection so that effective antibiotics can be given. Pulmonary function tests are used to measure how well the lungs are functioning and is used to measure the need for and response to antibiotic therapy. Blood tests can identify liver problems, vitamin deficiencies, and the onset of diabetes. DEXA scans can screen for osteoporosis and stool testing for fecal elastase can help diagnose insufficient pancreatic enzymes. [edit] Prenatal diagnosis Couples who are pregnant or who are planning a pregnancy can be tested to determine the likelihood that their child will be born with cystic fibrosis. Testing is typically performed first on one or both parents and, if the risk of CF is found to be high, testing on the fetus can then be performed. Because prenatal diagnosis does not allow for better or different treatment of children with CF, the main reason for testing is to offer abortion if the fetus is found to have CF. Cystic fibrosis testing is offered to all couples who are interested in prenatal testing.[17] However, testing, as of 2006, is recommended for couples who have a personal or close family history of CF as well as couples at high risk because of their ethnicity such as those with Northern European or Ashkenazi Jewish ancestry.[18] Because development of CF in the fetus requires each parent to pass on a mutated copy of the CFTR gene and because CF testing is expensive, testing is often performed on just one parent initially. If that parent is found to be a carrier of a CFTR gene mutation, the other parent is then tested to calculate the risk that their children will have CF. Testing is accomplished by analyzing the blood of the parents. CF can result from more than a thousand different mutations and, as of 2006, it is not possible to test for every one. Testing typically looks for the most common mutations such as ΔF508 — most commercially available tests look for 32 or fewer different mutations. If a family has a known mutation, screening can also look for this individual mutation. Because all of the known mutations are not found on current tests, screening is incomplete and the chance of having a child with CF still exists despite a negative screen.[19] In addition, because the mutations tested are necessarily those most common in the highest risk groups, testing in lower risk ethnicities is less successful because the mutations commonly seen in these groups are less common in the general population. Parents who are at high risk for having a child with CF, such as couples where both parents are carriers, will often opt to perform further testing. Testing can be performed prior to pregnancy on female eggs (oocytes) in a process called preimplantation genetic diagnosis. After pregnancy, testing can be performed on the placenta (chorionic villus sampling) or the fluid around the fetus (amniocentesis). However, chorionic villus sampling has a risk of fetal death of 1 in 100 and amniocentesis of 1 in 200[20], so the benefits must be determined to outweigh these risks prior to going forward with testing. Alternatively, some couples choose to undergo third party reproduction with egg or sperm donors. [edit] Pathophysiology Cystic fibrosis occurs when there is a mutation in the CFTR gene. The protein created by this gene is anchored to the outer membrane of cells in the sweat glands, lung, pancreas, and other affected organs. The protein crosses this membrane and acts as a channel connecting the inner part of the cell (cytoplasm) to the surrounding fluid. This channel is primarily responsible for controlling the movement of chloride from outside the cell into the cell. When the CFTR protein does not work, chloride is trapped outside the cell. Because chloride is negatively charged, positively charged ions also cannot cross into the cell because they are affected by the electrical attraction of the chloride ions. Sodium is the most common ion in the extracellular space and the combination of sodium and chloride creates the salt which is lost in high amounts in the sweat of individuals with CF and forms the basis for the sweat test.[2] How this malfunction of cells in cystic fibrosis causes all of the clinical manifestations of CF is not well understood. One theory suggests that the lack of chloride absorption through the CFTR protein leads to the accumulation of nutrient–rich mucus in the lungs which allows bacteria to grow hidden from the body's immune system. Another theory proposes that the CFTR protein failure leads to a paradoxical increase in sodium and chloride uptake which, by leading to increased water reabsorption, creates mucus which is dehydrated and thick. Yet another theory focuses on abnormal chloride movement out of the cell which also leads to dehydration of mucus, pancreatic secretions, biliary secretions, etc. These theories all support the observation that the majority of the damage in CF is due to blockage of the narrow passages of affected organs with thickened secretions. These blockages lead to increased risk of remodeling and infection in the lung, damage by accumulated digestive enzymes in the pancreas, blockage of the intestines by thick stool, etc.[2] [edit] The role of chronic infection in lung disease The lungs of individuals with cystic fibrosis are colonized and infected by bacteria from an early age. These bacteria thrive in the altered mucus which collects in the small airways of the lungs. This mucus helps protect the bacteria from the immune system, in part by encouraging the development of bacterial biofilms which allow bacteria to create a microenvironment which is difficult for immune cells (and antibiotics) to penetrate. Over time, the body's response to repeated damage by thick secretions and chronic infections leads to remodeling of the lower airways (bronchiectasis) which makes infection even more difficult to eradicate. Over time, both the types of bacteria and their individual characteristics change in individuals with CF. Initially, common bacteria such as Staphylococcus aureus and Hemophilus influenzae colonize and infect the lungs. Over time, however, Pseudomonas aeruginosa and Burkholderia cepacia come to dominate. Once within the lungs, these bacteria adapt to the environment and develop resistance to commonly used antibiotics. Pseudomonas can develop special characteristics which allows the formation of large colonies — these strains are known as "mucoid" Pseudomonas and are rarely seen in people who do not have CF. One way in which infection has spread is by passage between different individuals with CF.[21] In the past, people with CF often participated in summer "CF Camps" and other recreational gatherings.[22][23] Hospitals grouped patients with CF into common areas and routine equipment (such as nebulizers)[24] was not sterilized between individual patients.[25] This led to transmission of more dangerous strains of bacteria among groups of patients. As a result, individuals with CF are routinely isolated from one another in the health care setting and health care providers are encouraged to wear gowns and gloves when examining patients with CF in order to limit transmission of virulent bacterial strains.[26] Often, patients with particularly damaging bacteria will attend clinics on different days and in different buildings than those without these infections. [edit] Molecular biology CFTR protein Cartoon showing the molecular structure of the CFTR protein The CF gene is found on chromosome 7, is 180,000 base pairs long, and creates a protein which is 1480 amino acids long. The most common mutation, ΔF508 results from a deletion (Δ) of three nucleotides which results in a loss of the amino
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chemamr
| Forum Hero Topics: 340 Posts: 4448
CF, giardia and celiac dz can cause steatorrhea. Giardia can also cause a simple diarrhea with no fat.
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