%0 Case Reports %T M2 Genotype of Varicella zoster virus associated with Severe Herpes zoster in Pakistan. %A Hanif S %A Majeed AI %A Faryal R %J Pak J Med Sci %V 40 %N 6 %D 2024 Jul %M 38952536 %F 2.34 %R 10.12669/pjms.40.6.8764 %X This case report is of herpes zoster which is caused by Varicella zoster virus (VZV). The patient was presented with acute renal failure associated with intravenous acyclovir administration for its management. A 50 years old man visited the hospital with rashes on his back. The serum sample was positive for anti-VZV IgM via Enzyme Linked Immunosorbent Assay (ELISA), and vesicular swab for VZV via polymerase chain reaction (PCR). Phylogenetic analysis identified it as M2-genotype. Patient was treated with intravenous acyclovir administration, which led to acute renal failure. Later with shift to oral acyclovir, renal functions were restored. Elderly patients with reactivation of VZV in Pakistan are at risk to contract herpes zoster. Acyclovir is drug of choice via intravenous route was found to be nephrotoxic, however oral acyclovir was safe and effective. This is first report on pathogenic VZV genotype from Pakistan and is presented to highlight that the herpes zoster cases of elderly patients' treatment option need to be revisited.