Dead bone in bladder- sequestrum perforating into urinary bladder leading to hydroureteronephrosis masquerading as bladder calculus.

Sequestrum formation is a known complication of osteomyelitis. This is usually a source of chronic non resolving infection and inflammation. We present a rare case of pelvic sequestrum following septic arthritis of hip joint invading into the urinary bladder mimicking a bladder calculus and leading to hydroureteronephrosis.