We present successful treatment of a patient with tubular colonic duplication complicated by fecal impaction, perforation and fecal peritonitis. This anomaly is usually detected in children younger 2 years old. In adulthood, this diagnosis is of a precedent-setting nature. If the diagnosis was not confirmed in early childhood, the absence of typical clinical picture, long-term course of disease and difficult interpretation of clinical data complicate subsequent verification of congenital anomaly. Only infectious complications and emergency surgery in adults can make a correct diagnosis.