[Skin changes - trivial or an indication of a more serious underlying disease?]

We present a 64-year-old immunosuppressed patient with dialysis-dependent kidney disease who was referred to our emergency department due to fever, weakness, and an unclear inflammatory condition. Initially, a soft tissue infection was suspected due to skin changes on both lower extremities. A soft tissue biopsy performed previously on an outpatient basis revealed erythema nodosum. A chest CT scan showed findings consistent with tuberculosis. The diagnosis was confirmed microbiologically in the bronchoalveolar lavage. When the patient subsequently developed decreased alertness, a cranial MRI was performed, which showed changes suggestive of tuberculosis. Disseminated tuberculosis was therefore assumed. Under the established tuberculosis-specific therapy, there was a renewed increase in inflammatory parameters, which we interpreted as a paradoxical upgrading reaction. In patients with multiple risk factors for tuberculosis and a newly developed inflammatory condition, tuberculosis diagnostics should be performed at an early stage.