Toxoplasma infection in kidney donors and transplant recipients from Western Mexico: A one-year follow-up.

PURPOSE: Solid organ transplant recipients are highly susceptible to Toxoplasma gondii infection. We aimed to describe the 12-month follow-up risk of seroconversion in renal transplant recipients. METHODOLOGY: Anti-T gondii antibodies were investigated in donors and recipients of renal transplants. In donors, anti-T gondii were evaluated before transplantation. In recipients, anti-T gondii were monitored over a 12-month period to evaluate potential seroconversion or reactivation. IgG and IgM anti-T gondii antibodies were investigated through enzyme immunoassay and Western blot. Molecular diagnosis was performed on peripheral blood leukocytes using PCR to amplify fragments corresponding to the T gondii B1 gene and the repetitive 529-bp element. RESULTS: The basal frequency of seropositive IgG anti-T gondii antibodies was higher in donors than in recipients (38.4% vs 25.2%; P = .03). During the 12-month follow-up, the accumulated seroconversion to IgG and IgM antibodies was 3/99 (3.0%), and the accumulated reactivation was 11/99 (11.0%). None of the samples exhibited positivity to T gondii DNA. CONCLUSIONS: This study showed that there is an increased risk of seroconversion or reactivation in renal transplant recipients over a 12-month follow-up. Our data suggest that prophylaxis with trimethoprim and sulfamethoxazole effectively prevented toxoplasmosis, since neither T gondii DNA nor clinical toxoplasmosis was detected.

Occult hepatitis B in kidney transplants recipients and donors from Western Mexico.

BACKGROUND: Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in serum and/or liver from HBsAg-negative subjects. Our aim was to determine OBI frequency in serum and genomic DNA in patients undergoing renal transplant and their cognate donors in a selected population from Western Mexico. METHODS: Blood samples were obtained from 94 donors and their cognate recipients (188 participants) before kidney transplantation. Identification of HBV DNA was carried-out by nested (S-region) and semi-nested (Pol-region) PCR in both genomic and serum DNA samples from 188 participants at pre-surgical stage and from a subset of 73 recipients at three-month follow-up. RESULTS: HBV-DNA was not detected in either genomic or serum DNA samples from recipients or donors prior to transplantation. After three-months of follow-up, 2 out of 73 (2.7%, 95% CI: 0.9-11.9%) recipients were positive to HBV-DNA (Pol-region) in genomic DNA samples using a high sensitivity Taq DNA polymerase. CONCLUSIONS: OBI incidence in recipients of kidney transplant may be higher than previously recognized. Detection of HBV-DNA was higher in genomic DNA than in serum samples using a high sensitivity Taq DNA polymerase. To the best of our knowledge, this is the first report regarding this specific topic in Mexicans.