Kaposi Sarcoma Under Immunosuppression

Figure 2

Clinical image of the left foot of the 82-year-old patient with early patchstage Kaposi sarcoma. A diffuse, brownish-livid skin lesion is visible. The patch stage represents the earliest manifestation of Kaposi sarcoma and is characterized by superficial vascular proliferations without nodular formation.

An 82-year-old woman developed a brownish-livid skin lesion which, over several months, had steadily spread from the toes to the left forefoot. The patient had a long-standing history of psoriatic arthritis, which was in remission under treatment with the IL-17 inhibitor ixekizumab 80 mg every 4 weeks, methotrexate (MTX) 10 mg per week, and low-dose prednisolone. On biopsy, early patch-stage Kaposi sarcoma with HHV-8-positive endothelial cells was diagnosed. A low viral load of HHV-8 DNA was also detected in blood. HIV testing was negative, and the patient’s travel history was unremarkable. Following diagnosis, MTX therapy was discontinued, prednisolone was gradually reduced, and ixekizumab was continued, under which a psoriasis flare occurred and was treated locally. Radiotherapy was initiated for the local Kaposi sarcoma and led to a regression of the lesion. This case illustrates a likely iatrogenic, HHV-8–associated Kaposi sarcoma under immunosuppression. The literature describes only isolated cases in immunosuppressed patients with inflammatory rheumatic diseases; data on its occurrence under IL-17 blockers are not available to date.

Thea Thiele, Georg Martin Norbert Behrens, Klinik für Rheumatologie und Immunologie,
Medizinische Hochschule Hannover, [e-mail]

Conflict of interest statement: The authors declare that no conflict of interest exists.

Translated from the original German by Christine Rye.

Cite this as: Thiele T, Behrens GMN: Kaposi sarcoma under immunosuppression.
Dtsch Arztebl Int 2026; 123: 219b. DOI: 10.3238/arztebl.m2026.0020