Erythema nodosum and hepatitis B virus (HBV) infection.
D002648:Child; D004893:Erythema Nodosum / Q000209:etiology*; D006509:Hepatitis B / Q000150:complications*; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006801:Humans; D008297:Male
D006514:Hepatitis B Surface Antigens