Iatrogenic Kaposi’s sarcoma following immunosuppressive treatment of the recurrent longitudinally extensive transverse myelitis

Introduction. Iatrogenic Kaposi’s sarcoma (KS) represents a multifocal, angioproliferative tumor that develops in patients undergoing immunosuppressive treatment and is considered to be induced by activation of latent human herpes virus type 8 (HHV8) infection. The aim of this report is to present a patient with iatrogenic KS due to immunosuppressive treatment. Case outline. We present a 69-year-old male non-HIV patient, previously treated for anti-aquaporin-4 antibody negative recurrent longitudinal extensive transverse myelitis with prednisolone and azathioprine for one year. The patient developed bluish and violet plaques and nodules on his face, trunk, and extremities. Skin biopsy findings (histopathology and immunohistochemical detection of CD31 expression and anti-HHV8 antibodies in the spindle cells) confirmed the diagnosis of KS. The reduction of immunosuppression and topical treatment with imiquimod resulted in a partial but significant regression of skin lesions, but the patient had another relapse of myelitis following the cessation of azathioprine and a reduction in the dose of prednisolone. Conclusion. To the best of our knowledge, this is the first case of an inflammatory and demyelinating central nervous system disease treated with corticosteroids and azathioprine that was associated with iatrogenic KS. The efficient treatment of both conditions is highly challenging and can be troublesome in specific cases.