A challenging diagnosis of pyrexia of unknown origin: isolated iliac tuberculous lymphadenitis complicated by psoas abscess

Pyrexia of unknown origin is a challenge in clinical practice. Extrapulmonary tuberculosis is considered a common cause for pyrexia of unknown origin which has a wide spectrum of clinical manifestations, culminating in delayed diagnosis. However, due to its treatable nature and good prognosis, a high index of suspicion is needed to diagnose atypical presentations. This case report elaborates isolated involvement of iliac lymph node in tuberculosis which is a rare presentation of tuberculous lymphadenitis.