title: Vitamin D deficiency is associated with increased risk of bacterial infections after kidney transplantation.
abstract: OBJECTIVE
  There may be an association between vitamin D levels and allograft outcomes in kidney transplant recipients (KTRs). However, few studies have been conducted to determine the association between vitamin D levels and post-transplant infections. This study investigated the impact of vitamin D deficiency on the risk of infection after kidney transplantation.
  
  
  METHODS
  We measured 25-hydroxyvitamin D (25(OH)D) levels prior to kidney transplantation. Vitamin D deficiency was defined as a serum 25(OH)D level < 20 ng/mL. We examined the incidence of various post-transplant infections during follow-up period. We used Cox proportional hazards regression analysis to determine factors associated with increased risk of post-transplant infections during the follow-up period.
  
  
  RESULTS
  A total of 164 KTRs were followed up for a mean of 24.8 ± 10.7 months. Among them, 135 patients (82.3%) had vitamin D deficiency. Patients with vitamin D deficiency had a significantly higher incidence of urinary tract infection (p= 0.027) and any bacterial infection (p= 0.010) compared to those without vitamin D deficiency. Vitamin D deficiency was not significantly associated with incidence of viral or fungal infections. Cox proportional hazards regression analysis revealed that vitamin D deficiency (hazard ratio, 11.07; 95% confidence interval, 1.46 to 84.03;p= 0.020) was independent risk factor for post-transplant bacterial infections.
  
  
  CONCLUSIONS
  Pre-transplant vitamin D deficiency was a significant risk factor for bacterial infections after kidney transplantation. Further studies are needed on possible benefits of vitamin D supplementation for preventing post-transplant bacterial infection.
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Young-Jae
authors.initials: YJ
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Sang-Un
authors.initials: SU
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Kyung-Hee
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Jong-Hak
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Eugene
authors.initials: E
authors.lastname: Kwon
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Hee-Yeon
authors.initials: HY
authors.lastname: Jung
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Ji-Young
authors.initials: JY
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Jang-Hee
authors.initials: JH
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Sun-Hee
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Yong-Lim
authors.initials: YL
authors.lastname: Kim
authors.affiliation: Department of Surgery, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Hyung-Kee
authors.initials: HK
authors.lastname: Kim
authors.affiliation: Department of Surgery, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Seung
authors.initials: S
authors.lastname: Huh
authors.affiliation: Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Chan-Duck
authors.initials: CD
authors.lastname: Kim
mesh_terms: D000328:Adult; D001424:Bacterial Infections / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006084:Graft Rejection / Q000209:etiology; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology*; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D014808:Vitamin D Deficiency / Q000150:complications*
keywords: Bacterial infections; Kidney transplantation; Vitamin D deficiency