Nicotinamide for Skin-Cancer Chemoprevention in Transplant Recipients.

BACKGROUND: Immunosuppressed organ-transplant recipients have an increased incidence of, and mortality from, skin cancer. Nicotinamide (vitamin B3) enhances the repair of ultraviolet (UV) radiation-induced DNA damage, reduces the cutaneous immunosuppressive effects of UV radiation, and reduces the incidence of keratinocyte cancers (including squamous-cell and basal-cell carcinomas) and actinic keratoses among high-risk immunocompetent patients. Whether oral nicotinamide is useful for skin-cancer chemoprevention in organ-transplant recipients is unclear. METHODS: In this phase 3 trial, we randomly assigned, in a 1:1 ratio, organ-transplant recipients who had had at least two keratinocyte cancers in the past 5 years to receive 500 mg of nicotinamide or placebo twice daily for 12 months. Participants were examined for skin lesions by dermatologists at 3-month intervals for 12 months. The primary end point was the number of new keratinocyte cancers during the 12-month intervention period. Secondary end points included the numbers of squamous-cell and basal-cell carcinomas during the 12-month intervention period, the number of actinic keratoses until 6 months after randomization, safety, and quality of life. RESULTS: A total of 158 participants were enrolled, with 79 assigned to the nicotinamide group and 79 to the placebo group. The trial was stopped early owing to poor recruitment. At 12 months, there were 207 new keratinocyte cancers in the nicotinamide group and 210 in the placebo group (rate ratio, 1.0; 95% confidence interval, 0.8 to 1.3; P = 0.96). No significant between-group differences in squamous-cell and basal-cell carcinoma counts, actinic keratosis counts, or quality-of-life scores were observed. Adverse events and changes in blood or urine laboratory variables were similar in the two groups. CONCLUSIONS: In this 12-month, placebo-controlled trial, oral nicotinamide therapy did not lead to lower numbers of keratinocyte cancers or actinic keratoses in immunosuppressed solid-organ transplant recipients. (Funded by the National Health and Medical Research Council; ONTRANS Australian New Zealand Clinical Trials Registry number, ACTRN12617000599370.).

Is there a higher prevalence of methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) colonization in patients with antibiotic allergy labels?

BACKGROUND: A penicillin allergy label has been associated with significantly higher rates of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) colonization, and correspondingly poorer clinical outcomes. However, there are limited data examining the association between any antibiotic label and colonization rates. We sought to evaluate if there is a relationship between patients with an antibiotic allergy label and prevalence of MRSA or VRE colonization. METHODS: We retrospectively reviewed all patients with an MRSA surveillance culture between December 15, 2014 and January 31, 2015, or a VRE surveillance culture between January 1, 2013 and January 31, 2015, at a tertiary community-based teaching hospital. Our primary objective was to evaluate the prevalence of MRSA or VRE colonization among patients with and without antibiotic allergies. Bivariate analyses included the χ² test and the Student t test to determine statistical significance for categorical and continuous variables, respectively. RESULTS: We included a total of 1,053 unique patients screened for MRSA, and 290 unique patients screened for VRE. The rate of MRSA and VRE colonization was 5.8% (62 of 1,053) and 32.4% (94 of 290), respectively, in our cohort. Antibiotic allergies were documented in approximately 1 out of 3 patients, 337 (32%) for the MRSA group and 94 (32%) for VRE group. There was a significant difference in MRSA colonization between patients with and without an antibiotic allergy, 28 of 337 (8.3%) versus 34 of 716 (4.7%) (P = .025), respectively. In contrast, there was no significant difference in antibiotic allergy rates with and without VRE colonization, 34 of 94 (36.2%) versus 92 of 196 (46.9%) (P = .10), respectively. CONCLUSIONS: An antibiotic allergy label was associated with significantly higher rates of MRSA colonization but no statistical difference with VRE colonization.