An Unusual Case of Chilaiditi Syndrome and Recurrent Colonic Ileus in a Patient with Polymyositis

Introduction: Polymyositis is an idiopathic inflammatory myopathy that involves skeletal muscles and spares smooth muscles. In this case we report extremely rare potential colonic involvement related to polymyositis. Case description/methods: A 47-year-old male with a history of polymyositis was admitted for muscle weakness attributed to polymyositis flare. He was noted to have noticeable abdominal distention despite passing stool and no other gastrointestinal symptoms. CT abdomen showed marked 12 cm dilation in the mid-transverse colon with a left upper quadrant transition point and mesenteric lymph node inflammatory changes (Fig. 1). Additionally, it demonstrated transposition of distended right flexure between the liver and the right hemi-diaphragm, consistent with Chilaiditi syndrome (Fig. 2). There was no clinical improvement despite conservative management with bowel regimen and electrolyte repletion; thus, the patient underwent endoscopic decompression, demonstrating stool in the colon and rectum, pan-colic dilation (Fig. 3) and patchy mild mucosal inflammation. His distension resolved, and he was discharged home. A few months following discharge, he was readmitted with decompensated heart failure and was noted to have recurrence of abdominal distension. Conservative management with oral polyethylene glycol and rectal sodium phosphate in addition to electrolytes correction resulted in gradual symptom resolution without the need for endoscopic decompression, and he was discharged home. Discussion: This case illustrates potential smooth muscle involvement in polymyositis, which is known to exclusively affect skeletal muscles. Due to skeletal muscle inflammation, polymyositis is associated with electrolyte imbalance and use of narcotics, which makes the diagnosis and the treatment challenging, despite worrisome imaging finding and severe degree of dilation noted on exam and imaging. This case is not associated with critical toxic mega-colon findings which gives room and time to treat conservatively and avoid invasive measures.Figure 1.: marked dilation in the mid-transverse colon.Figure 2.: transposition of distended right flexure between the liver and the right hemi-diaphragm, consistent with Chilaiditi syndrome( red arrow).Figure 3.: pan-colic dilation and patchy mild mucosal inflammation.