Polyclonal hypergammaglobulinemia and high smooth-muscle autoantibody titers with specificity against filamentous actin: consider visceral leishmaniasis, not just autoimmune hepatitis

摘要

Visceral leishmaniasis (VL) remains a public health problem in most countries bordering the Mediterranean basin. Its diagnosis is challenging and often delayed, as the main clinical picture is often indistinguishable from that of other infectious and non-infectious diseases. Herein, we report two unusual cases of VL that presented with several characteristics of autoimmune hepatitis (AIH). Neither patient had a history of fever, only generalized symptoms accompanied by polyclonal hypergammaglobulinemia, cytopenias, signs of portal hypertension, elevated transaminases, and high titers of antinuclear and smooth-muscle autoantibodies (SMA) with reactivity against filamentous actin (F-actin), which has been recognized as specific to AIH. A clinical diagnosis of AIH was considered, but a bone marrow biopsy was performed before a liver biopsy to exclude a primary bone marrow disease. The biopsy led to the diagnosis of VL. The diagnosis was further confirmed by IgG antibodies against Leishmania spp. using ELISA and PCR-based assays. Treatment with amphotericin in the first case and pentamidine in the second (because of a severe reaction to amphotericin) was effective. From the clinical point of view, it should be emphasized that, in cases with high titers of anti-F-actin AIH-specific SMA accompanied by polyclonal hypergammaglobulinemia, the possibility of AIH should be cautiously differentiated from VL; this distinction is of paramount importance because initiation of immunosuppression for AIH treatment would be detrimental to a patient with underlying leishmaniasis. Therefore, in such cases and in areas where the disease is still present, it seems rational to exclude VL before starting any immunosuppressive therapy.