A 40-year-old white man complains of slowly progressive generalized weakness, weight loss, abdominal pain, and wrist and knee pain over the past several months. He was told at an urgent care visit that his blood sugar was a little higher than normal. There is a family history of liver disease on his father’s side. On examination, the patient has diffuse hyperpigmentation and a palpable liver edge. Mild polyarthritis of the wrists is also noted.
What is the best test or combination of tests to help you diagnose this patient’s problem?
Hemochromatosis is an autosomal recessive condition that causes increased intestinal absorption of iron and excessive total body iron stores. The cause is a defect in the HFE or related gene; it affects Caucasians most frequently at a rate of about 1 in 250 persons. Clinically, the liver is usually enlarged, and excessive skin pigmentation is present in 90% of symptomatic patients at the time of diagnosis. Diabetes occurs secondary to direct damage to the pancreas by iron deposition. Arthropathy develops in 25% to 50% of cases. Initial screening involves transferrin saturation (iron/total iron binding capacity) and ferritin levels. A transferrin saturation of over 45% or a ferritin over 150 would be consistent with the diagnosis and would suggest the need for referral and genetic testing. A simple CBC would not suggest the diagnosis. The hemoglobin A1C is helpful in diagnosing and monitoring diabetes. Patients with alpha-1-antitrypsin deficiency have liver disease but not diabetes or arthropathy. A liver-spleen scan could detect cirrhosis but would not be specifically helpful in determining whether or not the patient has hemochromatosis as the cause.
A 32-year-old white woman complains of abdominal pain off and on since the age of 17. She notices abdominal bloating relieved by defecation as well as alternating diarrhea and constipation. She has no weight loss, GI bleeding, or nocturnal diarrhea. On examination, she has slight LLQ tenderness and gaseous abdominal distension. Laboratory studies, including CBC, are normal.
Which of the following is the most appropriate initial approach?
This patient meets the Rome II criteria for irritable bowel syndrome. The major criterion is abdominal pain relieved with defecation and associated with change in stool frequency or consistency. In addition, these patients often complain of difficult stool passage, a feeling of incomplete evacuation, and mucus in the stool. In this young patient with long-standing symptoms and no evidence of organic disease on physical and laboratory studies, further evaluation (ie, colonoscopy or small bowel studies for sprue) is unnecessary. Irritable bowel syndrome is a motility disorder associated with altered sensitivity to abdominal pain and distension. It is the commonest cause of chronic GI symptoms and is three times more common in women than in men. Associated lactose intolerance may cause similar symptoms and should be considered in all cases. Patients older than 40 years with new symptoms, weight loss, or positive family history of colon cancer should have further workup, usually with colonoscopy.
A 55-year-old white woman has had recurrent episodes of alcohol-induced pancreatitis. Despite abstinence, the patient develops postprandial abdominal pain, bloating, weight loss despite good appetite, and bulky, foul-smelling stools. KUB shows pancreatic calcifications.
In this patient, you should expect to find which of the following?
Chronic pancreatitis is caused by pancreatic damage from repeated attacks of acute pancreatitis. The classic triad is abdominal pain, malabsorption, and diabetes mellitus. Twenty-five percent of cases are idiopathic. Vitamins D and K are absorbed intact from the intestine without digestion by lipase and are therefore absorbed normally in pancreatic insufficiency. Forty percent of patients, however, develop B12 deficiency. Treatment of the malabsorption with pancreatic enzyme replacement will lead to weight gain, but the pain can be difficult to treat. Courvoisier sign is a palpable, nontender gallbladder in a jaundiced patient. This finding suggests the presence of a malignancy, usually pancreatic cancer. Chronic pancreatitis per se does not produce guaiac-positive stools. Amylase is usually normal in patients with chronic pancreatitis.
A 34-year-old white woman is treated for a UTI with amoxicillin. Initially she improves, but 5 days after beginning treatment she develops recurrent fever, abdominal bloating, and diarrhea with six to eight loose stools per day.
What is the best diagnostic test to confirm your diagnosis?
Clostridium difficile is an important cause of diarrhea in patients who receive antibiotic therapy. Clostridium difficile proliferates in the gastrointestinal tract when the normal enteric bacteria are altered by antibiotics. Commonly implicated antibiotics include ampicillin, clindamycin, cephalosporins, and trimethoprim-sulfamethoxazole. The diarrhea is usually mild to moderate, but can be profuse. Other clinical findings include fever, abdominal pain, abdominal tenderness, leukocytosis, and serum electrolyte abnormalities. The diagnosis is made by demonstration at sigmoidoscopy of yellowish plaques (pseudomembranes) that cover the colonic mucosa or by detection of C difficile toxin in the stool. The pseudomembranes consist of a tenacious fibrinopurulent mucosal exudate that contains extruded leukocytes, mucin, and sloughed mucosa. Isolation of C difficile from stool cultures is nonspecific because of asymptomatic carriage, particularly in infants. Testing for fecal leukocytes is also nonspecific and may be negative in C difficile colitis. Serological tests are not clinically useful for diagnosing this infection. Although Clostridia are indeed gram-positive bacilli, they cannot be distinguished microscopically from numerous other anaerobic organisms in stool. Pseudomembranous colitis demands discontinuation of the offending antibiotic. Antibiotic therapy for moderate or severe disease includes oral metronidazole or vancomycin. Cholestyramine can be used therapeutically to bind the diarrheogenic toxin.
A 27-year-old woman is found to have a positive hepatitis C antibody at the time of plasma donation. Physical examination is normal. Liver enzymes reveal ALT of 62 U/L (normal < 40), AST 65 U/L (normal < 40), bilirubin 1.2 mg/dL (normal), and alkaline phosphatase normal. Hepatitis C viral RNA is 100,000 copies/mL. Hepatitis B surface antigen and HIV antibody are negative.
Which of the following statements is true?
This patient has chronic hepatitis C. A positive test for hepatitis C viral RNA confirms the diagnosis. Liver biopsy is not necessary for confirmation, but may be useful in predicting need for treatment. Chronic hepatitis C rarely resolves spontaneously. Untreated, about 15% of patients with hepatitis C will eventually develop cirrhosis. The levels of ALT and viral RNA correlate poorly with histologic disease and eventual prognosis. Treatment with pegylated interferon and ribavirin is aimed at preventing cirrhosis. Females, patients under age 40, patients with minimal or no cirrhosis, and those infected with genotypes 2 and 3 are more likely to respond to treatment. All patients with chronic hepatitis C should receive vaccination against hepatitis A and B, which can cause fulminant hepatic failure in patients with preexisting hepatitis C.
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