Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (178 page)

   Signs and symptoms of the prodromal phase usually abate with the onset of jaundice and the acute phase of hepatitis.

   Acute hepatitis may be icteric or anicteric. The majority of cases of acute HCV infections and HAV and HBV infections in children are anicteric.

   Asymptomatic: Many patients infected with hepatitis viruses may remain clinically asymptomatic or show only mild or transient symptoms. The diagnosis of viral hepatitis may be suspected by finding abnormal LFT or other tests collected for other reasons.

   Symptomatic, icteric:

   Patients develop jaundice; examination of the sclerae may provide the most sensitive site for detection. LFT and other laboratory testing demonstrates liver cell damage and the extent of hepatic function compromise. The levels of conjugated and unconjugated bilirubin are typically comparable. In acute hepatitis, there is usually marked elevation of aminotransferases, with ALT > AST; the degree of elevation does not correlate with the extent of hepatic cellular damage. LD may be mildly elevated. Serum AST and ALT fall rapidly in the several days after jaundice appears and become normal 2–5 weeks later with resolution of infection.

   Other laboratory tests may be abnormal, depending on severity of the disease. ALP and albumin levels are usually normal. Serum protein electrophoresis may show mild elevation of the γ-globulin fraction. Serum cholesterol-to-ester ratio is usually depressed early; total serum cholesterol is decreased only in severe disease. Serum phospholipids are increased in mild but decreased in severe hepatitis. Urine urobilinogen is increased in the early icteric period; at peak of the disease, it disappears for days or weeks; urobilinogen simultaneously disappears from stool.

   Severe hepatocellular damage is predicted by prolonged PT, markedly elevated bilirubin, hypoglycemia, or decreased serum albumin concentration. A prolonged and complicated course is more common in the elderly, in patients with significant underlying medical (especially hepatic) conditions, and in patients presenting with severe symptoms, like peripheral edema or encephalopathy during the acute phase.

   Symptomatic, anicteric: Laboratory abnormalities are usually mild compared to patients with icteric hepatitis; there is slight or no increase in serum bilirubin.

   Nonspecific laboratory abnormalities may be associated with the acute phase of viral hepatitis. ESR is increased but decreases during convalescence. Serum iron is often increased. Urine examination may show cylinduria, and albuminuria occurs occasionally. The renal concentrating ability is sometimes decreased.

   Acute Fulminant Hepatitis/Acute Liver Failure (ALF)

   Acute fulminant hepatitis may be recognized by triad of prolonged PT, increased PMNs, and nonpalpable liver. A prolonged PT, especially >20 seconds, indicates the likely development of acute hepatic insufficiency; therefore, the PT should be performed with the initial patient evaluation.