A 2 month old baby with acute viral hepatitis like illness slips into encephalopathy after 48 hours. The mother is a known hepatitis B carrier Mother’s hepatitis B virus serological profile is most likely to be:
First, I need to recall the different HBV serological markers. The core concept here is understanding the different serological profiles and their clinical significance. Hepatitis B has various antigens and antibodies. The key markers are HBsAg, anti-HBs, HBeAg, anti-HBe, HBcAg, and anti-HBc.
Acute hepatitis B typically presents with HBsAg positive, anti-HBc IgM positive. If someone is a carrier, they might have chronic infection, which usually means HBsAg positive, anti-HBc IgG positive, and HBeAg positive if they are in the replicative phase. If they're in the inactive phase, HBeAg might be negative but anti-HBe positive.
The baby developed encephalopathy. That's a red flag. Encephalopathy in the context of hepatitis can be due to fulminant hepatic failure. In infants, perinatal transmission of HBV is a concern. If the mother is a carrier, especially with high viral load (HBeAg positive), the risk of transmission is very high. In such cases, the infant might present with acute hepatitis, which can rapidly progress to liver failure and encephalopathy.
The mother's serological profile would be the one that indicates high infectivity. HBeAg positive status means active viral replication and high infectivity. So the mother's profile would be HBsAg positive, HBeAg positive, and anti-HBc IgG positive. That's the typical profile for a chronic carrier in the active phase.
Looking at options, the correct one would have HBsAg and HBeAg positive. The other options might have anti-HBeAg or anti-HBs, which would be less likely in a carrier with active virus. For example, if the mother had anti-HBeAg, that would indicate a lower viral load and less infectivity. Anti-HBs would mean immunity, which isn't the case here. So the correct answer would be the option with HBeAg positive.
Clinical pearl: Remember that HBeAg positivity in the mother is a strong indicator of high viral load and increased risk of perinatal transmission. In such cases, infants should receive HBIG and the vaccine promptly to prevent infection.
**Core Concept**
This question tests understanding of hepatitis B virus (HBV) serological profiles and perinatal transmission. A mother with **HBsAg+, HBeAg+** indicates active viral replication and high infectivity, increasing the risk of neonatal fulminant hepatitis and encephalopathy.
**Why the Correct Answer is Right**
The mother’s **HBsAg+** (surface antigen) confirms chronic HBV infection. **HBeAg+** (e antigen) indicates active viral replication and high infectivity. This profile correlates with perinatal HBV transmission, leading to neonatal acute hepatitis progressing to encephalopathy. The infant’s rapid deterioration aligns with fulminant hepatic failure from high maternal viral load.
**Why Each Wrong Option is Incorrect**
**Option A:** *