A renal transplant recipient is found to have rising creatinine levels. Which organism is primarily identified through a Urine PCR assay?

The correct answer is BK virus. In renal transplant recipients, the rise in creatinine levels may indicate kidney dysfunction or rejection, and BK virus is a well-recognized pathogen associated with kidney transplant complications. Urinary PCR assays are highly effective in detecting BK virus, as this virus typically resides in the urinary tract and can cause nephropathy in transplant patients.

BK virus is a member of the polyomavirus family and is frequently reactivated in individuals who are immunocompromised, such as those who have undergone kidney transplantation. The ability to identify BK virus through a urine PCR assay is crucial because early detection allows for timely management, potentially reducing the risk of progressive kidney injury and improving overall transplant outcomes.

Other pathogens listed, such as Hepatitis C virus, Legionella pneumophila, and Epstein-Barr virus (EBV), do not have the same association with urinary involvement in the context of kidney transplant dysfunction and are not primarily detected through urine PCR assays. Hepatitis C is typically tested through blood samples, while Legionella pneumophila is diagnosed via respiratory secretions, and EBV is more often evaluated through serological testing or blood PCR, not a urine assay.