A 25-year-old man is hospitalized with fever, anorexia, and fatigue. He admits to IV drug abuse and many episodes of unprotected sex over the past few years. His condition is treated and he is discharged from the hospital. The patient follows up with his physician regularly over the next 8 months, and the following serologic marker dynamics are obtained (see the graph below). *Grey bars indicate the detectable presence of the specified serum marker.This patient most likely:

Question

A 25-year-old man is hospitalized with fever, anorexia, and fatigue.  He admits to IV drug abuse and many episodes of unprotected sex over the past few years.  His condition is treated and he is discharged from the hospital.  The patient follows up with his physician regularly over the next 8 months, and the following serologic marker dynamics are obtained (see the graph below).  *Grey bars indicate the detectable presence of the specified serum marker.This patient most likely:

Quizplus · Accepted Answer

The serologic markers for hepatitis B infection appear on a predictable timeline with a long asymptomatic incubation period (lasting an average of 6-8 weeks) followed by acute disease lasting several weeks to months. HBsAg first appears before the onset of symptoms, peaks when the patient is most ill, and then becomes undetectable in 3-6 months (unless the disease progresses to a chronic phase). Shortly after HBsAg first appears, HBeAg and HBV DNA can be detected in the serum and are markers of active viral replication. Anti-HBcAg IgM and elevated serum transaminases appear shortly before symptom onset. Over the next few months, the anti-HBcAg IgM component is replaced with an IgG component. Anti-HBeAg appears shortly after HBeAg vanishes and suggests subsiding viral activity (transition from high viral replication/infectivity to low viral replication/infectivity). Anti-HBsAg IgG arises once the acute disease has resolved (unless the disease progresses to a chronic phase), and is typically not detectable until weeks or months after HBsAg has disappeared. This antibody may persist indefinitely, conferring lifelong immunity. Given this serologic marker graph, it appears that this patient has a persistence of HBsAg and HBeAg over a long period with low to moderate levels of anti-HBcAg IgG and no detectable Anti-HBsAg. These findings are suggestive of an acute hepatitis B infection that has not resolved, but rather has progressed to a highly infectious chronic hepatitis B (note the persistence of HBeAg and lack of anti-HBeAg). (Choice A) Were this patient to have fully recovered from his bout of acute hepatitis B, all antigens should have dropped to undetectable levels and he should have high levels of anti-HBsAg IgG and anti-HBcAg IgG. (Choice B) An exacerbation of preexisting hepatitis B would be characterized by a decline followed by a spike in antigen levels. (Choice C) Acute hepatitis B that progressed to chronic hepatitis with low infectivity would be indicated by a graph similar to the one shown for this patient. However, there would be low or undetectable levels of HBeAg (the marker for high infectivity) and likely detectable quantities of anti-HBeAg. (Choice E) Vaccination against HBV would be identified by a surge in anti-HBsAb with no anti-HBcAg, anti-HBeAg, or viral antigens detected. Educational objective: If HBeAg persists for several months and host anti-HBeAg remain at low or undetectable levels, suspect chronic hepatitis B infection with high infectivity.

A 25-Year-Old Man Is Hospitalized with Fever, Anorexia, and Fatigue