Unusual presentation of Hepatitis A viral infection

Hepatitis A virus is a nonenveloped 27-nm, heat-, acid-, and ether-resistant RNA virus in the Hepatovirus genus of the picornavirus family. Its virion contains four capsid polypeptides, designated VP1 to VP4, which are cleaved posttranslationally from the polyprotein product of a 7500-nucleotide genome. Hepatitis A has an incubation period of 4 weeks. Its replication is limited to the liver, but the virus is present in the liver, bile, stools, and blood during the late incubation period and acute preicteric phase of illness. Despite persistence of virus in the liver, viral shedding in feces, viremia, and infectivity diminish rapidly once jaundice becomes apparent. The diagnosis of hepatitis A is made during acute illness by demonstrating anti-HAV of the IgM class. After acute illness, anti-HAV of the IgG class remains detectable indefinitely, and patients with serum anti-HAV are immune to reinfection. Neutralizing antibody activity parallels the appearance of anti-HAV, and the IgG anti-HAV present in immune globulin accounts for the protection it affords against HAV infection. Patients develop abrupt onset of prodromal symptoms of malaise, joint pain (11%), right upper quadrant pain, and evanescent rash (14%) even weeks before developing jaundice (40% to 70%) in acute infection. Atypical manifestations of prolonged cholestasis, relapsing hepatitis, and extra hepatic involvement, which are rare unlike in hepatitis B or hepatitis C, may be present. Extra hepatic manifestations may include acute kidney injury, urticarial and maculopapular rash, polymyositis, arthralgias, and suppurative parotitis that can be seen in both prodrome and acute infection. Polymyositis can result in rhabdomyolysis, as seen in our patient with elevated creatinine phosphokinase and myoglobinuria. Many cases of acute kidney injury associated with hepatitis A infection have been described in endemic areas. We present an unusual complication of Hepatitis A infection presenting in a 14 year old young boy with encephalitis and refractory seizures.