title: Clostridium difficile-associated diarrhea in heart transplant recipients: is hypogammaglobulinemia the answer?
abstract: BACKGROUND
  Information regarding Clostridium difficile-associated diarrhea (CDAD) after solid-organ transplantation (SOT) is scarce, particularly after heart transplantation (HT). Although host immune response to C. difficile plays a substantial role in the outcome of this infection, the responsibility of hypogammaglobulinemia (HGG) as a predisposing condition for CDAD has not been studied in SOT. We analyzed the incidence, clinical presentation, outcome and risk factors, including HGG, of CDAD after HT.
  
  
  METHODS
  Two hundred thirty-five patients who underwent HT (1993 to 2005) were included. Transplantation procedure and immunosuppression were standard. From January 1999 HGG was systematically searched and corrected when IgG levels were <400 mg/dl or severe infection was present. Toxin-producing C. difficile was detected by means of cytotoxin assay and culture of stool samples. Patients with and without CDAD were compared for identification of risk factors.
  
  
  RESULTS
  CDAD was detected in 35 patients (14.9%). Incidence decreased significantly since HGG was sought and treated: 29 (20.6%) in the first period, and 6 (6.4%) in the second (p = 0.003). CDAD appeared a mean of 32 days (range 5 to 3,300 days) after HT. No related death or episode of fulminant colitis was detected. At least one episode of recurrence was noted in 28.6% of patients. Severe HGG was found to be the only independent risk factor for CDAD after HT (RR 5.8; 95% CI: 1.05 to 32.1; p = 0.04).
  
  
  CONCLUSIONS
  C. difficile is a significant cause of diarrhea in HT recipients and post-transplant HGG is independently associated with an increased risk. The potential role of immunoglobulin administration in this population requires further study.
authors.affiliation: Division of Clinical Microbiology and Infectious Diseases, Clinical Immunology Unit, Department of Cardiology, Hospital General Universitario Gregorio Marañón, University of Madrid, Madrid, Spain. pmunoz@micro.hggm.es
authors.forename: Patricia
authors.initials: P
authors.lastname: Muñoz
authors.forename: Maddalena
authors.initials: M
authors.lastname: Giannella
authors.forename: Luís
authors.initials: L
authors.lastname: Alcalá
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Sarmiento
authors.forename: Juan
authors.initials: J
authors.lastname: Fernandez Yañez
authors.forename: Jesus
authors.initials: J
authors.lastname: Palomo
authors.forename: Pilar
authors.initials: P
authors.lastname: Catalán
authors.forename: Javier
authors.initials: J
authors.lastname: Carbone
authors.forename: Emilio
authors.initials: E
authors.lastname: Bouza
mesh_terms: D000293:Adolescent; D000328:Adult; D000361:Agammaglobulinemia / Q000150:complications*; D000368:Aged; D019072:Antibiotic Prophylaxis; D016360:Clostridioides difficile; D003015:Clostridium Infections / Q000175:diagnosis / Q000276:immunology*; D003428:Cross Infection / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control; D003967:Diarrhea / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology*; D005260:Female; D016027:Heart Transplantation / Q000276:immunology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012008:Recurrence; D012307:Risk Factors
chemical_list: D007166:Immunosuppressive Agents