What should you know about extrahepatic manifestations of hepatitis B?

Hepatitis B is a viral infection centred in the liver, but immune activity related to the infection can sometimes affect other tissues. Possible features include aching or swollen joints, unusual skin rashes, inflammation of small blood vessels, kidney problems, or nerve symptoms. Fatigue and dark urine may occur with liver involvement but are not specific to hepatitis B. Some people have no symptoms, so a symptom outside the liver cannot confirm or exclude the infection.

Arrange medical review if you have known hepatitis B and develop a new rash, joint swelling, numbness, swelling of the legs, changes in urine, or worsening tiredness. A clinician may review your history, examine you, check blood and urine, and monitor liver markers with a Liver Function Test. Take hepatitis B medicines exactly as prescribed and do not stop them because you feel well. Avoid sharing razors or toothbrushes, and ask about Hepatitis B Vaccination for household or sexual contacts who may be unprotected.

Seek urgent help for confusion, extreme drowsiness, vomiting blood, black stools, severe abdominal swelling, very little urine, sudden weakness, or trouble breathing. Dark urine with yellowing of the eyes, severe pain, or rapidly worsening illness also deserves prompt assessment. These signs can have several causes and should not be judged by symptoms alone.

Ask whether your symptoms could be linked to hepatitis B or need a separate work-up, which blood or urine checks are planned, how often the liver should be monitored, and whether your close contacts need vaccination or testing.