9 GI qmx 7-21 Flashcards
Nonspecific gastrointestinal symptoms, such as upper abdominal pain and early satiety, are frequently the earliest signs of ?
- Weight loss and the palpable mass signal hepatomegaly likely caused by?
- This patient immigrated from Asia, and one of his parents had liver cancer. A transmissible cause of hepatocellular carcinoma (HCC) such as hepatitis B virus (HBV), which is endemic to Asia, is the most likely cause of ?
- liver pathology.
- cirrhosis and/or cancerous growth. This is further confirmed by elevated liver transaminase levels (aspartate aminotransferase and alanine aminotransferase much more elevated than alkaline phosphatase) and decreased synthetic function (hypoalbuminemia and increased coagulation times suggesting inadequate liver production of proteins and clotting factors).
- this patient’s liver pathology. HBV-associated HCC may occur in younger adults (20–40 years old) without cirrhosis because HBV may integrate into the host genome of hepatocytes and induce oncogenic changes.
HBV infection is the most common cause of HCC. It is endemic in much of Asia and Africa, spreading from parents to children and frequently resulting in chronic infection. HBV-associated HCC may occur in the absence of cirrhosis and at an earlier age than HCV-associated HCC because ?
HBV DNA may directly integrate into the host genome, predisposing hepatocytes to neoplastic changes.
The patient’s history, her report of malodorous and bulky diarrhea that ceases with fasting, and a presumed increase in stool fat content (as stools float in water) are suggestive of ?
malabsorption.
One easy way to test for malabsorption is a 72-hour fecal fat collection. This involves having the patient follow a 100-g fat diet for 3 days, followed by measurement of fat in the stool.
- Malabsorption can result from multiple causes, including:?
- This patient’s diabetes and epigastric pain suggest
Defective intraluminal digestion (eg, chronic pancreatitis);
Primary mucosal cell abnormalities (eg, celiac sprue, tropical sprue)
Reduced small intestinal surface area (eg, small bowel resection)
Lymphatic obstruction (eg, Whipple disease)
Impaired mucosal cell absorption secondary to an infectious agent (eg, Giardia lamblia)
- chronic pancreatitis secondary to chronic alcohol use as the cause of malabsorption.
Gut motility derangements, such as increased transit time, can result from?
neuromuscular dysfunction, which can be observed in patients with diabetic neuropathy or hyperthyroidism. Although this patient has diabetes, she does not have symptoms of diabetic neuropathy or hyperthyroidism.
A positive culture for Vibrio cholera would be associated with?
watery diarrhea, which this patient does not have.
The patient does not report blood or pus in the stool, so diarrhea caused by an infectious organism, such as ?
Shigella and certain types of Escherichia coli, can likely be ruled out.
Chronic pancreatitis commonly manifests as a ?
malabsorptive diarrhea, since the pancreas is no longer capable of secreting an adequate amount of amylase and lipase (which are responsible for the digestion of carbohydrates and lipids). Consequently, fats remain undigested in the intestines, which results in malabsorptive diarrhea.
This patient presents with lower abdominal cramping, fever and watery non-bloody diarrhea several days after being treated in the hospital for cellulitis with clindamycin. He most likely has?
pseudomembranous colitis, which is found primarily in hospitalized patients and caused by Clostridium difficile.
Clostridium difficile pseudomembranous colitis can manifest following treatment with broad-spectrum antibiotics, particularly with ampicillin and clindamycin. The first-line initial therapy recommended by treatment guidelines for this infection is metronidazole, which works by ?
damaging bacterial DNA via toxic free radical metabolite formation
This patient presents with jaundice, lethargy, and an elevated unconjugated bilirubin level. In a newborn, these signs and symptoms are suggestive of ?
Crigler-Najjar syndrome type 1. Crigler-Najjar syndrome type 1 is an autosomal recessive disorder characterized by unconjugated hyperbilirubinemia that is usually fatal within 18 months of birth, secondary to kernicterus.
Crigler-Najjar syndrome type 1 is an autosomal recessive disorder that is characterized by unconjugated hyperbilirubinemia secondary to ?
a loss of UGT1 activity. This leads to kernicterus, and it is typically fatal in the first few years of life.
A 35-year-old man presents to the clinic with progressive odynophagia, anorexia, and weight loss. His history includes use of intravenous heroin. On physical examination, the patient has submandibular lymphadenopathy and white plaques lining the tongue and throat as shown in the image. The plaques are easily scraped off with a tongue depresso…The patient’s weight loss and drug use are consistent with?
human immunodeficiency virus (HIV) infection. The oral and esophageal lesions described are thrush in an HIV-positive patient, caused by Candida albicans, a germ tube-positive fungus. Germ tubes are the initial form of hyphae that extend from the fungal spore. A standard test used to detect Candida involves incubating the specimen in a serum for 3 hours at 37°C (98.6°F) and then examining the spores for signs of germ tubes
A newborn boy is brought to the neonatologist for a checkup 24 hours after birth. His parents report that he has a poor appetite and is very constipated. He has not had a single bowel movement thus far. His abdomen is distended, but his bowel sounds are normal, and his abdomen does not appear to be tender. Barium enema shows a narrow rectosigmoid with a dilation of the segment above the narrowing?
This patient has Hirschsprung disease (shown in this image, which depicts a barium enema X-ray of the colon), which manifests when neural crest cells fail to migrate to the distal colon. These neurons are normally responsible for relaxation of the rectum to allow defecation. If this condition is left untreated, these infants run the risk of developing enterocolitis or a bowel perforation. Hirschsprung disease is associated with Down syndrome, caused by trisomy 21. Children with Down syndrome also have an increased risk of duodenal atresia, congenital heart disease, and acute leukemia.
The description of colonic inflammation with exudates and necrosis of the mucosal surface describes?
the pseudomembranous colitis of Clostridium difficile, of which there have been several outbreaks. C. difficile is a gram-positive anaerobe spore-former that produces toxin A (which causes diarrhea) and toxin B (which is cytotoxic). AB toxin causes cell apoptosis. Later stages of C. difficile infection can result in necrosis as described in the vignette. Strains that produce an increased amount of these toxins have led to increased morbidity and even death associated with C. difficile colitis.
