A 53-year-old white woman with schizophrenia was transferred from a psychiatric center after vague complaints of shortness of breath led to obtaining a chest x-ray film, which revealed significant subdiaphragmatic free air (Figure 1). On admission, the patient was alert and oriented; she insisted she was medically healthy and admitted only to mild abdominal distention. She denied current shortness of breath or any other GI complaints and further denied recent fever or chill. Her past history was significant for scleroderma and uncontrolled schizophrenia that resulted from nonadherence to prescribed aripiprazole.
On initial examination, the patient was alert and cooperative, appeared well with stable vitals, and had no abnormal cardiopulmonary findings. Her abdominal examination showed diffuse distention and tympany, minimal tenderness to palpation, normal bowel sounds, and no guarding or rebound. Her only other significant physical findings were sclerodactyly and diffuse xerosis. The findings from her complete blood cell count, complete metabolic panel, and urinalysis were within normal limits; her toxicology screen result was negative.
CT scans of the patient’s chest, abdomen, and pelvis further detailed the pneumoperitoneum and showed intraluminal free air alongside gravity-defying intramural air in the small intestine, although there were no signs of perforation (Figure 2). Of note, the radiographs revealed esophageal stricture with proximal dilatation in addition to pneumoperitoneum, consistent with the patient’s diagnosis of scleroderma (Figure 3).
Radiographic findings of air collections within the wall of the patient’s intestines established pneumatosis cystoides intestinalis (PCI) as the cause of her spontaneous pneumoperitoneum. The combination of a benign abdomen on examination, the absence of any other explanation for pneumoperitoneum, and the presence of the typical findings for PCI in a patient with scleroderma fully supported this diagnosis.