Chronic intestinal pseudo-obstruction complicated with sand-like enterolithiasis: case report.

Enterolithiasis is typically associated with gastrointestinal tract stasis. Here, we report on a rare case of chronic intestinal pseudo-obstruction with sand-like enterolithiasis in an 18-year-old Japanese female admitted to our hospital with high fever and abdominal pain. Despite initiating antibiotic treatment, the fever persisted. A contrast-enhanced computed tomography revealed colonic enlargement and a large amount of residue with a high-density area in the ascending colon. A colonoscopy revealed sand-like enteroliths in the ascending colon, which were drained using a colonoscope. The patient's symptoms improved significantly after the drainage and antibiotic therapy. The granules were white-brown in color and smaller than 300 μm in size. Infrared spectroscopy indicated similar peaks for crystals and hydroxypropyl cellulose which is an additive used in certain medications. We hypothesized that hydroxypropyl cellulose contributed to the formation of sand-like enteroliths in cases of severe intestinal dysmotility. Intestinal failure may cause enterolithiasis due to an unharmful additive and require careful follow-up.