Granulomatous
hepatitis is a common cause of
fever of unknown origin in up to 13% of patients with prolonged
fever. Attempts to define an exact etiology of the granulomatous
hepatitis frequently does not yield a precise diagnosis, so that the physician must consider empiric treatment. In this paper we retrospectively review 23 patients in whom granulomatous
hepatitis was found as part of the initial assessment of
fever of unknown origin, and we report on their outcomes after an overall prospective follow-up of 37 months. In 26% a precise diagnosis was established at the time of assessment:
Q-fever in three, mycobacterial disease in two, and
histoplasmosis in one. In the remaining 74% no etiology was established after 44 months follow-up. Forty-one percent of the idiopathic group resolved spontaneously without
therapy, and 18% received short-term
prednisone or
indomethacin with a favourable outcome. The remaining 41% required long-term
prednisone therapy for a mean of 33.1 months, but all have remained afebrile and otherwise healthy after 59.6 months follow-up. We conclude that patients with
fever of unknown origin who are diagnosed as having idiopathic granulomatous
hepatitis have an excellent prognosis, even the minority who require long-term
corticosteroids.