[Acute hepatitis due to kava-kava and St John's Wort: an immune-mediated mechanism?]

In an otherwise healthy 48-year-old female patient, acute hepatitis with transaminase increase (GOT up to 613 U/l, GPT up to 752 U/l), inconspicuous hepatitis serology findings, negative autoantibody status and negative virus serology was observed after a 10-week long intake of kava-kava (1-3 x 200 mg/day) and St John's Wort (1 x 425 mg/day). Biopsy of the liver showed lobular and portal necroinflammatory activity without indication of cirrhosis.

Due to these findings with proven T-cell activity (lymphocyte typing, neopterin determination) as well as the aetiopathology, this form of hepatitis with histological characteristics of a nutritive/medicinal toxic origin was classified as induced immunologic idiosyncratic hepatitis, possibly in terms of an antibody-negative autoimmune hepatitis.

Discontinuation of the existing medication and simultaneous onset of immunosuppressive combination therapy of cortisone, azathioprine and ursodeoxycholic acid resulted in normalisation of the liver parameters within a period of two months.

On the one hand, it appears that simultaneous intake of St John's Wort possibly potentiates the toxicity of kavapyrones. On the other hand, an immune-mediated mechanism, induced by kava-kava, cannot be completely excluded in the present case. It must be stressed that in patients with autoimmune hepatitis, precise history of medication intake should also be available.