Sam Kant

The pandemic of coronavirus disease 2019 (CoVID-19) has been an unprecedented period. The disease afflicts multiple organ systems, with acute kidney injury (AKI) a major complication in seriously ill patients. The incidence of AKI in patients with CoVID-19 is variable across numerous international studies, but the high incidence of AKI and its associated worse outcomes in the critical care setting are a consistent finding. A multitude of patterns and mechanisms of AKI have been elucidated, and novel strategies to address shortage of renal replacement therapy equipment have been implemented. The disease also has had consequences on longitudinal management of patients with chronic kidney disease and end stage kidney disease. Kidney transplant recipients may be especially susceptible to CoVID-19 as a result of immunosuppression, with preliminary studies demonstrating high mortality rates. Increased surveillance of disease with low threshold for testing and adjustment of immunosuppression regimen during acute periods of illness have been recommended.

BK virus maintains a latent infection that is ubiquitous in humans. It has a propensity for reactivation in the setting of a dysfunctional cellular immune response and is frequently encountered in kidney transplant recipients. Screening for the virus has been effective in preventing progression to nephropathy and graft loss. However, it can be a diagnostic and therapeutic challenge. In this in-depth state-of-the-art review, we will discuss the history of the virus, virology, epidemiology, cellular response, pathogenesis, methods of screening and diagnosis, evidence-based treatment strategies, and upcoming therapeutics, along with the issue of re-transplantation in patients.

Levamisole is an antihelminth drug and a common cocaine contaminant, present in an estimated 71% of cocaine samples in the US. Levamisole-contaminated cocaine has been linked to an ANCA-associated vasculitis with cutaneous, renal, and pulmonary manifestations. We report the case of a 46 year old woman with known cocaine exposure who presents with recurrent, large purpuric and maculopapular rash of the extremities and face and review existing cases of levamisole/cocaine-associated ANCA vasculitis, We summarize the clinical presentation, treatment, and outcomes of levamisole induced vasculitis. There is emerging research on pathogenesis relating to neutrophil extracellular traps (NETs). We review studies implicating role of NETs in the pathogenesis of levamisole induced vasculitis. Further research to explore the use of NETs as therapeutic targets in drug induced vasculitis is needed.

Background. Approximately 15% of kidney transplant recipients (KTRs) develop BK viremia (BKV), with 1%–10% developing BK virus-associated nephropathy (BKVAN), which histologically resembles rejection. The Diagnosing Acute Rejection in Kidney Transplant Recipients (DART) study showed that donor-derived cell-free DNA (dd-cfDNA) levels <1% have a negative predictive value of 85% for active allograft rejection. Using data from this study, we evaluated the association of dd-cfDNA with plasma BK viral loads and biopsy findings to determine if dd-cfDNA can distinguish asymptomatic BKV from BKVAN. Methods. Data on dd-cfDNA, plasma BK viral loads, and biopsy findings from patients from the DART study were retrospectively examined. BKV was defined as 500–10 000 copies/mL. Presumptive BKVAN was defined as BK >10 000 copies/mL. Results. Of 102 participants with biopsies, 10 patients with BKV and BKVAN had paired dd-cfDNA, and viral loads available for analysis. Patients diagnosed with BKV and BKVAN had a median dd-cfDNA of 0.58% (IQR 0.43–1.15) and 3.38% (IQR 2.3–4.56, P = 0.001), respectively. dd-cfDNA titers correlated with BK PCR viral loads (R = 0.874, P = 0.01) and the presence of histologic evidence of BKVAN (100% sensitivity, 50% specificity). Five of 7 patients with BKVAN, but only 2 of 7 with BKV, had biopsies meeting Banff criteria for T-cell–mediated rejection. Median dd-cfDNA in nonrejection patients was 0.43% versus 2.84% in rejection patients ( P = 0.001). Conclusion. Higher dd-cfDNA titers were associated with higher BK viral loads, biopsy-diagnosed BVAN, as well histologic changes meeting Banff criteria for as T-cell–mediated rejection. dd-cfDNA may be a useful noninvasive test to assess for progression of BKV to BKVAN.