A 58-year-old male is being treated for Pseudomonas nosocomial pneumonia with cefepime. His symptoms improve, but 1 week later he develops fever and diarrhea with several loose nonbloody stools per day.
Given the likely diagnosis in this scenario, what is the treatment of choice?
Metronidazole. The patient in this clinical scenario has likely developed Clostridium difficile–associated diarrhea (CDAD). This gram-positive spore-forming bacterium is best known for causing antibiotic-associated diarrhea. It typically develops after treatment with fluoroquinolones, cephalosporins (as with this patient), carbapenems, or clindamycin. It can cause pseudomembranous colitis and rarely progresses to toxic megacolon. The treatment of choice is metronidazole with oral vancomycin being reserved for severe or in some cases of recurrent CDAD. Oral vancomycin is used instead of IV vancomycin because oral vancomycin is not absorbed from the gut into the bloodstream and therefore has maximum efficacy. (A, B, C) These antibiotics are associated with the development of CDAD and should not be used as treatment.
A 67-year-old woman of Japanese descent presents with 5 months of vomiting undigested food, hematemesis, and a 6.8-kg (15-lb) weight loss. Physical examination reveals a woman with tachycardia, conjunctival pallor, and a nontender, slightly mobile mass in the midepigastric region. The patient is noted to have hyperpigmented velvety plaques in her bilateral axillary regions and the base of her neck.
Which of the following is the most appropriate next step in management?
Upper GI endoscopy. The patient in this question is presenting with signs and symptoms concerning for gastric cancer. Symptoms of gastric cancer are very nonspecific and include weight loss, loss of appetite, abdominal discomfort, weakness, fatigue, nausea, vomiting, hematemesis, and many others. Risk factors for gastric cancer include H. pylori infection, smoking, and dietary intake of smoked foods or nitrates/nitrites in cured meats. Upper GI endoscopy is the diagnostic method of choice as the tumor can be visualized and abnormal tissue biopsied. Gastric cancer is also associated with acanthosis nigricans (as seen on dermatologic examination with this patient). (A, C) Abdominal ultrasound and barium swallow study will not permit biopsy of tissue, so they are not the preferred diagnostic modality. (D) H. pylori serologic testing might be performed to evaluate for risk factors, but will not determine the underlying diagnosis of gastric cancer. Tissue must be biopsied to establish the diagnosis.
A 27-year-old woman presents with anorexia, nausea, vomiting, and fever for the past 3 weeks. She reports that several of her friends have told her she looks “yellow.” Physical examination is significant for an enlarged and tender liver and jaundice. Viral hepatitis panel is ordered and demonstrates positive HCV RNA and anti-HCV antibody, consistent with hepatitis C infection.
Which of the following findings is NOT a risk factor for hepatitis C infection?
Contaminated food. The patient in this question has acute hepatitis C (HCV) infection. HCV is largely transmitted through IV drug use and blood transfusions (although blood transfusion transmission is exceedingly rare nowadays due to thorough blood screening). Much less commonly, HCV can be transmitted through sexual contact (but this is very uncommon for HCV and much more common in HBV transmission). Contaminated food and water is the cause of hepatitis A (HAV) infection through fecal–oral transmission and is not associated with HCV infection. Of all the viral hepatitides, hepatitis C infection is the most likely to become chronic (70% to 80% of HCV infections become chronic).
A 29-year-old woman presents with abdominal pain for the last 7 days. She describes the pain as “dull” and localized to the right upper quadrant. It does not radiate. She has a history of asthma and has taken oral contraceptive medication for birth control for the last 8 years. She reports no more than two to three glasses of wine per week and she does not use illicit drugs. She denies weight loss, fatigue, fevers, or chills. On physical examination, a palpable mass is appreciated in the right upper quadrant. Laboratory results are significant for an elevated gamma glutamyl transpeptidase (103 U/L) and elevated alkaline phosphatase (224 U/L). All other liver function tests are within normal limits.
Which is the most likely diagnosis in this patient?
Hepatic adenoma. The patient in this question is presenting with a history and symptoms consistent with hepatic adenoma (also known as hepatocellular adenoma). This is a relatively rare benign liver tumor that is associated with hormonal contraceptive medications with a high estrogen level. The mechanism of action for this association is not entirely known. A hepatic adenoma is usually diagnosed when patients (typically middle-aged women) present with abdominal pain in the right upper quadrant or when a patient collapses from rupture of the hepatic adenoma. Given the susceptibility to rupture, biopsy of the hepatic adenoma is contraindicated. In addition to a palpable right upper quadrant mass, findings occasionally include jaundice. Although liver function tests are typically normal, the most common abnormal laboratory tests include elevated gamma glutamyl transpeptidase and alkaline phosphatase. Of note, close to 10% of hepatic adenomas can turn malignant which is why α-fetoprotein levels are important to monitor in these patients. Surgical removal is only indicated with symptomatic hepatic adenomas. With asymptomatic hepatic adenomas, the recommendation is to discontinue oral contraceptive medications and monitor with serial α-fetoprotein levels (to ensure malignant transformation has not occurred).
(A) Hepatocellular carcinoma is highly unlikely given this patient’s young age, lack of heavy alcohol use, and no history of viral hepatitis. (C) Echinococcal (hydatid) cysts can present with similar vague abdominal complaints; however, this is a parasitic infection by a tapeworm. It is not endemic in the United States, so on the Internal Medicine shelf examination a history of recent immigration is likely to be present. (D) Alcoholic hepatitis would be highly improbable given the patient’s alcohol history (two to three glasses of wine per week).
A 51-year-old man with a history of chronic hepatitis C infection presents for follow-up. His only complaints include fatigue and “red dots” on his torso. Physical examination reveals spider angiomata as well as splenomegaly and evidence of mild ascites. Abdominal ultrasound at a previous visit showed a shrunken liver consistent with cirrhosis.
Which of the following screening tools is needed in the management of this patient?
Upper GI endoscopy. The patient in this question is presenting with compensated cirrhosis due to chronic viral hepatitis C infection. The first step in determining appropriate management for cirrhotic patients is to determine whether or not their condition is compensated (asymptomatic or nonspecific symptoms such as fatigue) or decompensated (upper GI bleeding, abdominal distention due to severe ascites, or mental status changes consistent with hepatic encephalopathy). In compensated cirrhosis, the goal is to prevent complications. Given the mortality associated with esophageal varices secondary to cirrhosis, it is critical that all cirrhotic patients get an upper GI endoscopy to determine the risk of variceal bleeding. Other screening modalities in compensated cirrhosis include ultrasound surveillance for hepatocellular carcinoma. (A) Ammonia levels are warranted if hepatic encephalopathy is suspected. However, this patient demonstrates no signs of confusion or asterixis. (B) Liver biopsy is really the only way to diagnose cirrhosis with 100% certainty, but the patient’s previous ultrasound in combination with physical examination findings are highly suggestive of cirrhosis, thereby making biopsy unnecessary. (D) Close observation and routine follow-up should be done in all patients with cirrhosis. However, screening modalities are indicated to prevent decompensated cirrhosis.
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