Urologists should remain constantly alert for patients with acute abdominal emergencies who may be admitted under their care with the erroneous diagnosis of acute retention. These cases are not uncommon. The patients may be suffering from suppression of urine, or their inability to pass urine may be the predominant symptom of their intra-abdominal catastrophe. When catheterization has yielded only a small amount of concentrated urine and has failed to relieve the patient's discomfort, think of an acute abdomen, investigate this possibility and treat the patient accordingly.