A 36-year-old man presents with cramping abdominal pain, urgency, bloody diarrhea, and weight loss. Physical examination reveals lowgrade fever, heme positive stools, and tenderness to palpation in the lower abdomen. Colonoscopy with biopsy is performed and the diagnosis of Crohn disease is made.
Which of the following findings is not associated with Crohn disease?
: Loss of haustral markings (lead-pipe colon). Distinguishing the two types of inflammatory bowel disease (IBD), Crohn disease and ulcerative colitis, is crucial to performing well on the gastroenterology questions on the medicine shelf examination. It is very difficult to determine the diagnosis simply from symptoms, although ulcerative colitis is more likely to be associated with bloody diarrhea and “cramping” abdominal pain, as opposed to the “colicky” pain often seen in Crohn’s. Given the nonspecific symptoms of IBD, a colonoscopy with biopsy is crucial to making the correct diagnosis. (B, C, D, E) Crohn disease is a chronic inflammatory bowel disease involving transmural (affecting the entire bowel wall) inflammation that can occur anywhere from the mouth to the anus (skip lesions). Crohn’s patients can present not only with lesions in the colon but also with lesions in the small bowel and even oral ulcers. Extraintestinal manifestations are common in Crohn disease as well, and include perirectal abscesses and fistulas. Biopsy in Crohn disease reveals noncaseating granulomas with mononuclear cell infiltrate. Ulcerative colitis, on the other hand, is associated with friable mucosa with ulcerations and erosions on colonoscopy; barium enema often reveals a lead-pipe colon with loss of haustra. Biopsy in ulcerative colitis reveals crypt abscesses and microulcerations (but no granulomas).
A 29-year-old woman presents to the physician because of fatigue, dark urine, nausea, vomiting, and decreased appetite. She reports that the symptoms started 1 month ago and have worsened in the last week. She has an insignificant past medical history but does endorse IV drug use as well as unprotected sexual intercourse with several partners over the last 6 months. She is unable to recall her immunization history. Laboratory results show elevated AST (210 U/L) and ALT (352 U/L) levels. The physician determines she is at high risk for hepatitis B virus.
What laboratory test(s) should be ordered to screen for ACUTE hepatitis B infection?
HBsAg and IgM anti-HBc. Testing for HBsAg and IgM anti-HBc is the best screening test for acute hepatitis B infection. HBsAg is the first marker detected in the blood after exposure and actually occurs before elevation in AST/ALT levels or clinical symptoms. HBsAg can be detected throughout the symptomatic phase of acute hepatitis B infection and its presence is indicative of infectivity. Anti-HBc appears shortly after HBsAg appears and the IgM component indicates the acute phase of the disease, whereas the IgG component indicates recovery from the disease. The period between the disappearance of HBsAg and the appearance of anti-HBs is called the “window period.” IgM anti-HBc is present during the “window period” when anti-HBs is not yet detectable and thus is used as a marker for the diagnosis of acute hepatitis. (A, B, C) HBeAg appears soon after HBsAg appears and indicates active viral replication and very high infectivity. It is followed by anti-HBe, and its presence for more than 3 months signifies an increased probability of chronic hepatitis B. Anti-HBs is present in individuals who have been vaccinated or have cleared HBsAg; thus it is present for life.
A 39-year-old woman presents with epigastric pain that has radiated to her back for the last 8 hours. She endorses nausea and vomiting. Her past medical history is significant for hyperlipidemia; however, she does not take any medications other than a multivitamin. She denies alcohol or drug use. On examination, the patient is slightly febrile at 38.4°C, with a blood pressure of 114/83 mmHg, a heart rate of 98 beats per minute, and a respiratory rate of 22 breaths per minute. The patient has decreased bowel sounds and guarding in the midepigastrium.
Which of the following results is the most specific finding in this condition?
Elevated lipase. The patient in this question is presenting with signs and symptoms of acute pancreatitis (epigastric abdominal pain radiating to the back, nausea, and vomiting). The vast majority of cases (80%) result from gallstones and alcohol. However, other causes of acute pancreatitis can be remembered with the mnemonic GET SMASHED (Gallstones, Ethanol, Trauma, Steroids, Mumps, Autoimmune, Scorpion bite, Hyperlipidemia, ERCP, Drugs [specifically diuretics, gliptins, azathioprine, salicylates, steroids]).
Acute pancreatitis can be diagnosed through several modalities: physical examination demonstrating epigastric pain radiating to the back, elevated amylase and lipase levels (typically 3× higher than the normal limit), and abdominal imaging (CT) showing pancreatic enlargement with heterogeneous enhancement with IV contrast. Ultrasound is also helpful in diagnosing gallstone pancreatitis by visualizing gallstones in the gallbladder. Lipase has the greatest specificity of all possible tests and is usually more elevated than amylase in acute pancreatitis.
(A) Amylase can sometimes be normal in acute pancreatitis (particularly if the etiology is hyperlipidemia). Furthermore, amylase is not specific to the pancreas as there is not only pancreatic amylase but also salivary amylase. (B) Although elevated ALT is very useful in suggesting gallstone pancreatitis, it does not encompass all the causes of acute pancreatitis and therefore is not a specific test. (D) Positive fecal fat test is typically positive (>7 g/d) in chronic pancreatitis; however, chronic pancreatitis presents with symptoms of malabsorption (as opposed to pain) and is typically due to alcohol use (neither of which this patient endorses).
A 49-year-old man with an extensive history of intravenous drug abuse over 10 years ago presents with anorexia, nausea, and malaise. He also reports dark urine for the last 2 months. His past medical history is significant for bipolar type 2 disorder. He takes no medications and reports a distant history of alcohol abuse. Physical examination is significant for hepatomegaly but no ascites. The patient demonstrates no signs of depression. Laboratory results reveal the following.
A biopsy of the liver is performed that demonstrates bridging fibrosis.
Which of the following is the best next step in management of this patient?
Vaccinate him against hepatitis B virus (HBV) and Hepatitis A virus (HAV). The patient in this question has chronic hepatitis C virus (HCV) infection. Deciding to treat HCV depends on a variety of factors. Criteria for treatment that is considered “widely accepted” include patient age >18 years, liver biopsy demonstrating chronic hepatitis with bridging fibrosis, detectable serum HCV RNA, compensated liver disease (INR <1.5 without ascites), and stable laboratory findings such as creatinine and hemoglobin. Of note, contraindications to treatment include active and ongoing alcohol or drug abuse and uncontrolled depression, neither of which our patient demonstrates. Therefore, the decision to treat here is the best next step. Although the current gold standard HCV treatment is combination therapy with interferon and ribavirin, this is currently changing as research progresses to find more interferon-free regimens. However, regardless of the aforementioned criteria, the patient must be vaccinated against HBV and HAV. (A) Close observation is not the best step here as our patient meets all the criteria for treatment. (C) Upper endoscopy would be useful in a patient with cirrhosis who shows signs of portal hypertension (which our patient does not demonstrate). (D) Liver transplantation should only be considered in decompensated liver failure; however, our patient demonstrates normal INR and normal serum albumin levels.
A 27-year-old woman presents with diarrhea and abdominal pain for the last 8 months. She denies bloody stools, weight loss, or fatigue. The patient just recently started what she describes as a “stressful” career in investment banking. She is concerned that she might have Crohn disease as both her maternal uncle and maternal grandmother have the disorder. Further questioning reveals that the diarrhea and abdominal pain occur about once per week (generally Friday mornings before she gives her weekly presentation), and the other days she is “constipated.” The abdominal pain is alleviated after defecation. Physical examination is unremarkable.
What is the next best step in management for this patient?
Reassurance and recommendation for a high-fiber diet and exercise. This is a very common question on the Internal Medicine shelf examination. The patient in this question likely has irritable bowel syndrome (IBS) given that she endorses abdominal pain with altered bowel function (diarrhea and constipation), with complete relief of abdominal pain after defecation. The etiology of IBS is largely unknown, but may be related to psychological factors, autonomic nervous system abnormalities, and altered gut motor function. The patient should be reassured that this is not inflammatory bowel disease (IBD) given that she does not have cramping, bloody diarrhea, or systemic symptoms like weight loss or fatigue. Nonetheless, a high-fiber diet (30 g/d) should be emphasized as well as exercise and sufficient fluid intake. (C) Loperamide is an opioid-receptor agonist used in the treatment of diarrhea. This should only be considered in IBS if the diarrhea persists after the aforementioned recommendations are tried. (A) Colonoscopy can aid in diagnosing IBD (Crohn disease shows skip lesions and ulcerative colitis shows friable mucosa with ulcerations and erosions continuous from the anus). (B) Corticosteroids are used in the treatment of IBD.
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