Cutaneous tuberculosis as a manifestation of Pott's Disease: A diagnostic challenge in patients with Non-HIV immunosuppression

Tuberculosis (TB) is one of the most important public health issues in developing countries. The World Health Organization estimates that approximately 20%-40% of the world's population is infected. Pulmonary forms account for the majority of cases; however, it can manifest as extrapulmonary disease in 8.4%-13.7% of cases. Of these extrapulmonary forms of TB, only 1%-2% may have skin manifestations. Cutaneous tuberculosis (CTB) is relatively uncommon and is not a well-defined disease, which complicates diagnosis. We present two patients with Pott's disease that manifested as CTB, one with tuberculous gumma and the other with scrofuloderma. Both patients with non-HIV immunosuppression. The diagnosis of CTB was made by detecting Mycobacterium tuberculosis in skin samples by real-time polymerase chain reaction (Xpert MTB/RIF test) and Ziehl-Neelsen staining. The histologic findings described in these two forms of TB may vary or be absent in immunosuppressed patients, making diagnosis difficult.