In a first-in-the-world medical report in kidney transplant cases, doctors at Mumbai’s Jaslok Hospital have discovered life threatening side effects with antiviral valganciclovir in patients with a genetic defect prevalent in a subgroup of Indian transplant patients. A recent study helmed by Dr Madan Bahadur, Director, Department of Nephrology and Kidney Transplantation, highlighted that even though valganciclovir is commonly used after kidney transplant to prevent viral infection, patients with NUDT15 enzyme deficiency develop severely low blood counts after the medication making them prone to life threatening infections. According to Dr Ashay Shingare, Consultant Nephrologist at Jaslok Hospital, a genetic test revealed NUDT15 deficiency in one recent kidney transplant recipient and after stopping valganciclovir, his blood counts improved and infection resolved.