CUTANEOUS PROTOTHECOSIS AND DISSEMINATED HISTOPLASMOSIS IN A PATIENT USING ANTI-TNF: CASE REPORT
TL;DR
This case shows that persistent skin lesions in immunosuppressed patients warrant broad investigation, even during antifungal treatment, and that protothecosis should be considered in this differential diagnosis of histoplasmosis and cutaneous protothecosis in patients on anti-TNF-alpha therapy.
Abstract
Background: TNF-alpha inhibitors increase the risk of opportunistic granulomatous infections, mainly histoplasmosis and, less often, protothecosis, caused by achlorophyllous algae of the genus Prototheca. Case report: a 61-year-old man with rheumatoid arthritis and Sjögren's syndrome, on prednisone, golimumab and methotrexate, developed right elbow bursitis 30 days after starting golimumab. Joint fluid culture isolated Histoplasma capsulatum and chest CT showed pulmonary micronodules. Immunosuppressants were stopped and itraconazole, started initially, had to be switched to fluconazole due to intolerance. Nine months later he developed arthritis, subcutaneous edema, disseminated livedoid lesions and worsening lung findings. Skin biopsy showed no granulomas, but mycological examination and culture confirmed Prototheca wickerhamii; treatment with liposomal amphotericin B led to complete resolution. Discussion: no previous reports were found describing disseminated histoplasmosis and cutaneous protothecosis occurring together in a patient on anti-TNF-alpha therapy. Conclusion: this case shows that persistent skin lesions in immunosuppressed patients warrant broad investigation, even during antifungal treatment, and that protothecosis should be considered in this differential diagnosis.