A 17-year-old boy presented with a 3-day history of left upper quadrant abdominal pain; intermittent pain radiated to the right side. The patient complained of nonbilious vomiting and nausea and reported subjective fever. He also had a decreased appetite and up to 10 daily bouts of nonmucoid diarrhea.
The patient had no history of sick contacts or recent travel. He reported occasional use of recreational drugs.
Contrast-enhanced CT scanning of the patient’s abdomen and pelvis showed enterocolitis. On evaluation of the bones, a well-defined lucent lesion measuring between −896 and −913.7 Hounsfield units, isodense to bowel gas and consistent with air attenuation, was noted within the right ilium abutting the superior aspect of the right sacroiliac joint (top, left and right images). This lesion measured 1.4 × 0.97 × 1.4 cm. The right sacroiliac joint was normal. A tiny lucency of air attenuation was projecting over the superior aspect of the left sacroiliac joint, characteristic of “vacuum phenomenon” (bottom). No other bony abnormalities were identified.
The patient was admitted to the pediatric ward, and intravenous hydration was started. Stool cultures from the day of admission were positive for Salmonella. During the patient’s 2-day hospital stay, his symptoms improved and the diarrhea and vomiting resolved. The patient was not aware of any musculoskeletal symptoms.
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