• A Comprehensive Analysis of present of JC and BK viruses in Immunocompromised Patients over the Past Three Years in Iran (2021-2024)
  • Mahdiye Shirmohammad,1 Behnoush Ashoubi,2 Ghazaleh Malekizade,3 Kaveh Sadeghi,4,*
    1. Department of Molecular Diagnostics, NOOR Pathobiology Laboratory, Tehran, Iran
    2. Department of Molecular Diagnostics, NOOR Pathobiology Laboratory, Tehran, Iran
    3. Department of Molecular Diagnostics, NOOR Pathobiology Laboratory, Tehran, Iran
    4. Department of Microbiology, School of Medicine, Tehran University of Medical Sciences


  • Introduction: BK and JC viruses are polyomaviruses that primarily affect immunocompromised individuals, leading to significant clinical complications. Understanding their pathogenesis and epidemiology is crucial for developing effective management strategies, particularly in transplant recipients and patients undergoing immunosuppressive therapies. The objective of this research is to analyze samples sent for testing over the past three years to determine the positivity rate. We aim to identify which sample types yielded the highest rates of positive results and investigate any correlations between sample type and positivity. This analysis will provide insights into the effectiveness of different sampling methods in detecting target pathogens.
  • Methods: The laboratory received a diverse array of sample types, including urine, plasma, blood serum, and cerebrospinal fluid (CSF). Specifically, a total of 103 samples for JC virus testing and 105 samples for BK virus testing were collected and analyzed. The extraction of DNA from JC and BK viruses was performed using a standardized protocol to ensure high yield and purity suitable for downstream applications. Quantitative polymerase chain reaction (qPCR) was then employed to detect and quantify the viral DNA in the extracted samples, providing sensitive and specific measurements of viral load.
  • Results: The results indicated that the primary sample utilized for the JC test is cerebrospinal fluid (CSF). An alternative sample proposed for this test is the Urine sample. In the BK virus tests, 18% of the samples tested positive, with positivity rates of 36% in urine, 31% in serum, and 26% in whole blood. Notably, there was no observed overlap between the positivity rates for JC and BK viruses within the analyzed sample set.
  • Conclusion: The results of this study demonstrate that the superior positivity rates in urine (36%) and CSF underscore their effectiveness as diagnostic mediums for both JC and BK viruses, supporting recent recommendations for utilizing these sample types in clinical assessments. Importantly, the absence of overlap in positivity rates between JC and BK viruses suggests distinct viral behaviors and reinforces the necessity for targeted diagnostic strategies to optimize patient management.
  • Keywords: BK virus, JC virus, qPCR, immunocompromised.