Screening Coccidioides serology in kidney transplant recipients: A 10-year cross-sectional analysis.

BACKGROUND

Kidney transplant recipients (KTRs) are at risk for reactivation and complicated infection due to Coccidioides. Pre-transplant serological screening should provide benefit for patients from endemic areas. We evaluated Coccidioides seroprevalence by area of residence in KTRs at a major transplant program in Los Angeles.

METHODS

We performed cross-sectional analyses of adult KTRs who underwent transplantation at UCLA between 2007-2016. Patients with Coccidioides serology by enzyme immunoassay (EIA) before or within 14 days from transplantation were included. Patients were classified as living in highly, established, suspected, or not endemic areas by their residential zip code.

RESULTS

Overall prevalence of Coccidioides IgG and IgM were 1.4% and 2.8%, respectively. Of patients with positive serology, 31.4% had isolated IgG and 66.3% isolated IgM. Patients from established and highly endemic areas had IgG seropositivity of 3.7% versus 1.3% for patients living in suspected endemic areas(P < .01). Rates of IgM seropositivity were 3.7% compared to 2.8% respectively (P = .28). No patients from non-endemic areas had positive screening serology.

CONCLUSIONS

Pre-transplant serological screening for Coccidioides is recommended in kidney transplant candidates from endemic areas. We observed high seroprevalence among patients from highly and established endemic areas, for whom universal prophylaxis is recommended. For residents from less well-established areas of endemicity, serological screening showed benefit in identifying patients at risk. In patients with isolated EIA IgM, performing repeat and confirmatory tests is recommended. Patients from non-endemic areas had low risk of infection, however, a thorough social history is necessary to evaluate risk.