Hematochezia Associated with Sevalamer-Induced Mucosal Injury

Abstract

We present a case of a 61-year-old woman with end-stage renal disease (ESRD) who developed painless hematochezia following initiation of anticoagulation. Work-up revealed a large ulceration in the sigmoid colon, and histologic images revealed sevelamer crystals embedded in the colonic mucosa, consistent with sevelamer crystal-mediated injury. This is a novel cause of gastrointestinal hemorrhage that has not previously been described in the literature. Physicians should be aware of the potential for sevelamer-induced injury.

Sevelamer-associated ischemic colitis with perforation

“…2 Subsequently, Chintamaneni et al described a patient presenting with hematochezia who was found to have a 5 cm ulcer in the sigmoid colon. 3 Biopsy revealed sevelamer crystals entrapped in the ulcer bed. Sevelamer was discontinued without further bleeding, and the authors postulated that sevelamer crystals are directly toxic to the colonic mucosa and may result in ischemic injury.…”

“…[1][2][3][4] The histologic features of sevelamer crystals were first described by Swanson et al in a case series of upper and lower gastrointestinal tract biopsy and resection specimens and were validated by submitting crushed sevelamer tablets for histologic examination. 2 They described the crystals as nonpolarizable with a broad irregularly-spaced fish scale pattern and a two-toned appearance consisting of bright pink accentuations with a rusty yellow background.…”

“…Sevelamer was discontinued without further bleeding, and the authors postulated that sevelamer crystals are directly toxic to the colonic mucosa and may result in ischemic injury. 3 Okwara et al described a patient who presented with non-bloody diarrhea who was found to have a circumferential polypoid mass in the cecum. 4 Biopsy showed sevelamer crystals in association with necrosis and ischemic changes without evidence of dysplasia or malignancy, and the authors concluded that the mass formation was the result of sevelamer-induced colitis.…”

“…2 Subsequent cases of sevelamer-associated colonic mucosal injury presenting with hematochezia and of sevelamer-induced colitis with pseudotumor formation have been reported. 3,4 We would like to add to this small body of literature by reporting a case of sevelamer-associated ischemic colitis with perforation.…”

Long-Standing Diarrhea Associated With Sevelamer Crystalopathy in Colonic Mucosa

“…1 Previous case studies showing colonic sevelamer deposition have presented patients with lower gastrointestinal bleeding or diffuse abdominal pain rather than long-standing diarrhea. 2,3 Moreover, sevelamer deposition in the gastrointestinal tract is a relatively novel discovery and its association does not prove causality. Sevelamer first was described as irregularly spaced fish scales that were curved and broad in nature.…”