BK Polyomavirus-specific T cell immune responses in kidney transplant recipients diagnosed with BK Polyomavirus-associated nephropathy.

BACKGROUND: Adjustment of immunosuppression is the main therapy for BK polyomavirus (BKPyV)-associated nephropathy (BKPyVAN) after kidney transplantation (KT). Studies of BKPyV-specific T cell immune response are scarce. Here, we investigated BKPyV-specific T cell immunity in KT recipients diagnosed with BKPyVAN. METHODS: All adult KT recipients with BKPyVAN diagnosed at our institution from January 2017 to April 2018 were included. Laboratory-developed intracellular cytokine assays measuring the percentage of IFN-γ-producing CD4+ and CD8+ T cells, after stimulation with large-T antigen (LT) and viral capsid protein 1 (VP1), were performed both at the time of diagnosis and after adjustment of immunosuppression. RESULTS: We included 12 KT recipients diagnosed with BKPyVAN (7 proven, 4 presumptive, and 1 possible). Those with presumptive BKPyVAN had a median plasma BKPyV DNA load of 5.9 log10 copies/ml (interquartile range [IQR]: 4.9-6.1). Adjusted dosing of mycophenolic acid and tacrolimus with (86%) or without (14%) adjunctive therapies were implemented after diagnosis. There was a significantly higher median percentage of IFN-γ-producing CD4+ T cells to LT at a median of 3 (IQR: 1-4) months after adjustment of immunosuppression compared with at the time of diagnosis (0.004 vs. 0.015; p = 0.047). However, the difference between the median percentage of IFN-γ-producing CD4+ T cells to VP1 and CD8+ T cells to LT and VP1 did not reach statistical significance. Four (33%) patients achieved plasma BKPyV DNA clearance, and the remaining eight (67%) patients had persistent BKPyV DNAemia. Although eight (67%) patients developed allograft dysfunction, none required hemodialysis. CONCLUSIONS: We observed a marginal trend of BKPyV-specific CD4+ T cell recovery after adjustment of immunosuppression in KT recipients diagnosed with BKPyVAN. A further study would be benefited to confirm and better assess BKPyV-specific immune response after KT.

Epidemiology and outcomes of dengue in kidney transplant recipients: A 20-year retrospective analysis and comparative literature review.

BACKGROUND: Kidney transplant (KT) recipients in dengue-endemic areas are at risk of exposure. We investigated the epidemiology and outcomes from dengue in KT recipients at our transplant center and conducted a literature review. MATERIALS AND METHODS: We conducted a 20-year retrospective study of KT recipients who were diagnosed with laboratory-confirmed dengue from January 1997 to September 2017 according to the 2009 World Health Organization (WHO) classification. We analyzed clinical characteristics and treatment outcomes. RESULTS: There were 13 (0.7%) dengue cases among 1917 KT recipients with a median age of 39 years (interquartile ranges [IQR], 22-46); 54% were males. Cases occurred with a median onset of 24 months (IQR, 6-122) after KT. Dengue was diagnosed via dengue NS1 antigen (85%), IgM antibodies (38.5%), or RT-PCR (15.4%). Patients were classified as having dengue without warning sign (30.8%), with warning sign (53.8%), or severe dengue (15.4%). All patients resolved without complications, except one had hemophagocytic lymphohistiocytosis. Ten (76.9%) patients experienced eGFR reduction with a median of 13.7 mL/min/1.73 m2 (IQR, 8.3-20.5); eight (80%) had a full allograft function recovery. CONCLUSIONS: Dengue in KT recipients in endemic areas is uncommon. Although a transient decline in allograft function can occur, the overall clinical and allograft outcomes seem to be favorable.

Prevalence of Primary HIV Drug Resistance in Thailand Detected by Short Reverse Transcriptase Genotypic Resistance Assay.

BACKGROUND: HIV drug resistance (HIVDR) is the major cause of treatment failure after scaling up of antiretroviral therapy (ART). HIVDR testing prior to ART initiation is not routinely performed in resource-limited settings. We aimed to assess the prevalence of primary HIVDR by short reverse transcriptase (RT) genotypic resistance assay and evaluate of the impact of the mutations on the treatment outcomes. METHODS: A prospective cohort study was conducted in treatment-naïve HIV-infected patients. Fourteen major mutations of codon 99-191 on the RT gene were selected (K103N, V106A/M, V108I, Q151M, Y181C/I, M184V/I, Y188C/L/H, and G190S/A) at a cost of testing of 35 USD. The association between the presence of primary HIVDR and undetectable HIV RNA (<50 copies/mL) after 6 months of ART was determined. RESULTS: A total of 265 HIV-infected patients were included, with a median age of 35.2 (range, 16.8-75.2) years; 62.6% were males. The median (interquartile range) CD4 cell count at ART initiation was 216 (77-381) cells/mm3. The overall prevalence of primary HIVDR was 7.9%. The prevalence of each HIVDR mutation were K103N 6.0%, V106I 1.1%, V108I 0.4%, Y181C 2.3%, Y181I 0.7%, Y181V 0.4%, M184V 3.0%, M184I 1.5%, and G190A 2.3%. No associated factor of having primary HIVDR was determined. By multiple stepwise logistic regression, factors associated with undetectable HIV RNA after 6 months of ART were: having M184V/I (odds ratio [OR] 0.11; 95% confidence interval [CI] 0.02-0.62, p = 0.013), condom use (OR 2.38; 95% CI 1.12-5.06, p = 0.024), and adherence per 5% increase (OR 1.16; 95% CI 1.00-1.35, p = 0.044). CONCLUSIONS: The prevalence of primary HIVDR is approximately 8%; it is associated with detectable HIV RNA at 6 months after ART initiation. Routine "short RT" genotypic resistance assay should be considered in resource-limited settings to maximize treatment outcome.