{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T17:03:22Z","timestamp":1791479002090,"version":"4.3.4"},"reference-count":38,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T00:00:00Z","timestamp":1760486400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Background: Cytomegalovirus (CMV) remains a formidable complication in small bowel transplantation (SBT) due to the graft\u2019s high immunogenicity and profound immunosuppression required, with refractory disease representing a particularly devastating challenge. Case: We report an 18-year-old male who underwent SBT, complicated by recurrent acute rejection episodes requiring intensive immunosuppression. He developed refractory CMV disease, marked by non-response to first line therapy with ganciclovir\u2014despite the absence of genotypic resistance\u2014necessitating sequential use of foscarnet, dual antivirals, CMV immunoglobulin, and novel agents (maribavir and letermovir). Discussion: This case illustrates the multifactorial drivers of refractory CMV disease in SBT recipients, including donor\u2013recipient serostatus mismatch, profound immunosuppression through T-cell-depleting induction, corticosteroid exposure, and biologic therapy. It highlights the distinction between refractory and resistant CMV, and the role of combination antiviral strategies including novel agents to achieve disease control. Outcomes remain dismal despite aggressive and innovative therapies, underscoring the limited efficacy of interventions in the context of severe immunologic compromise. Conclusions: Refractory CMV enteritis in SBT exemplifies the extreme difficulty of balancing viral control with rejection management. Despite exhausting antiviral strategies, survival remains poor. Highlights: Refractory CMV enteritis is a significant challenge in small bowel transplant recipients due to intense immunosuppression. Persistent CMV disease may occur despite antiviral prophylaxis and the absence of resistant gene mutations. Combination antiviral strategies, including maribavir, demonstrated significant clinical improvement. Profound immunosuppression required to manage acute graft rejection episodes complicates antiviral management and disease clearance. Despite best efforts in CMV management in this population, outcomes may still be compromised by unrelated or compounding factors.<\/jats:p>","DOI":"10.3390\/v17101379","type":"journal-article","created":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T14:04:02Z","timestamp":1760537042000},"page":"1379","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Refractory CMV Enteritis in Small Bowel Transplantation: A Case Highlighting the Challenges of Balancing Immunosuppression and Novel Antiviral Therapies"],"prefix":"10.3390","volume":"17","author":[{"given":"Abdulrahman A.","family":"Al-Saud","sequence":"first","affiliation":[{"name":"Organ Transplant Centre of Excellence, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-3367-8604","authenticated-orcid":false,"given":"Ehab H.","family":"Abufarhaneh","sequence":"additional","affiliation":[{"name":"Organ Transplant Centre of Excellence, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madain S.","family":"Alsanea","sequence":"additional","affiliation":[{"name":"Research & Innovation Department, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reem M.","family":"Alameer","sequence":"additional","affiliation":[{"name":"Organ Transplant Centre of Excellence, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amani H.","family":"Yamani","sequence":"additional","affiliation":[{"name":"Organ Transplant Centre of Excellence, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1765-4310","authenticated-orcid":false,"given":"Fatimah S.","family":"Alhamlan","sequence":"additional","affiliation":[{"name":"Research & Innovation Department, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reem S.","family":"Almaghrabi","sequence":"additional","affiliation":[{"name":"Organ Transplant Centre of Excellence, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1066","DOI":"10.1097\/TP.0000000000005374","article-title":"The Fourth International Consensus Guidelines on the Management of Cytomegalovirus in Solid Organ Transplantation","volume":"109","author":"Kotton","year":"2025","journal-title":"Transplantation"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Zuhair, M., Smit, G.S.A., Wallis, G., Jabbar, F., Smith, C., Devleesschauwer, B., and Griffiths, P. (2019). Estimation of the worldwide seroprevalence of cytomegalovirus: A systematic review and meta-analysis. Rev. Med. 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