Possible antiviral effect of ciprofloxacin treatment on BKV replication in a patient with acute renal dysfunction: a case report

Acute renal dysfunction (ARD) is a common complication in renal transplant recipients. Multiple factors contribute to ARD development, including acute rejection episodes and microbial infections. Many viral infections after kidney transplantation result from reactivation of “latent” viruses in the host or from the graft, such as the human Polyomavirus BK (BKV). We report the case of a 39 year-old male re-transplant patient who developed a second acute humoral rejection episode associated to BKV reactivation. A 10-day treatment with the quinolone antibiotic ciprofloxacin was given as urinary infection prophylaxis after cystography concurrently with a strengthening of anti-rejection immunosuppressive therapy despite the active BKV replication. Real Time PCR (Q-PCR) analysis performed after treatment with ciprofloxacin, surprisingly showed the clearance of BK viremia and a regression of BK viruria. During the follow-up, BK viremia persisted undetectable while viruria further decreased until disappear at all after 3 months. The molecular characterization of BKV non-coding control region (NCCR) from all positive samples always showed the presence of archetypal sequences, with two single-nucleotide substitutions and one nucleotide deletion that, interestingly, were all representative of the subtype/subgroup I/b-1 we identified by viral protein 1 (VP1) sequencing analysis. The most relevant contribute of this report is that the quinolone antibiotic ciprofloxacin administration could have contributed to reduce and to solve the BKV load in both blood and urine. These data suggest that quinolones (at least ciprofloxacin) could be used to treat ARD episodes with long-term administration necessary for a durable antiviral effect.