Case Report: Malakoplakia Developing in the Graft Colon Post Intestinal Transplant

Abstract

Abstract Casestudy Malakoplakia is a rare chronic granulomatous disease thought to be caused by a macrophage bactericidal defect and most commonly affecting the genitourinary tract. Most cases are associated with chronic infections or immunosuppression, with most transplant related cases observed after renal transplantation. Results A male in his thirties developed short gut syndrome secondary to injuries and subsequently underwent a small and large bowel transplant and was treated with immunosuppressive medications. He developed multiple episodes of acute rejection and multiple infectious foci, including a peri-rectal fluid accumulation growing Escherichia Coli, bacteremia with Klebisella oxytica, and Epstein Barr Virus viremia. Functional imaging revealed increased activity in mesenteric lymph nodes and in the peri-rectal fluid accumulation. On endoscopy, a rectal ulcer associated with mucosal protuberance was noted and tissue was obtained for pathologic diagnosis. Histologic examination revealed mucosal infiltration by numerous macrophages with abundant granular cytoplasm. Michaelis-Gutmann bodies (considered pathognomonic for malakoplakia) were identified showing PAS and Von- Kossa positivity. Acid fast stain was negative. These findings supported the diagnosis of malakoplakia. Other differential diagnoses were considered, including post-transplant lymphoproliferative disorder, neoplasia, infection with mycobacterial or fungal species, and secondary hemophagocytic lymphohistiocytosis syndrome. These were excluded based on the characteristic histologic findings. Given the diagnosis, treatment with oral antibiotics was attempted. Follow up biopsies revealed disease persistence and the patient was transitioned to a prolonged course of intravenous antibiotics and bethanechol, with eventual histologic response. Unfortunately, due to stenosis and adhesions that developed secondary to the episodes of acute rejection, the patient eventually underwent graft explanation. Conclusion Our case highlights the risk factor milieu encountered in intestinal transplant patients and the prolonged treatment often required to treat malakoplakia. Additionally, malakoplakia constitutes an unusual consideration in intestinal transplant patients and prompt diagnosis is required to direct proper management of these patients.