Background: Solid organ transplant recipients (OTR) are at increased risk for herpes zoster (HZ), primarily due to immunosuppressive medication. HZ may cause to serious complications including cutaneous dissemination, postherpetic neuralgia (PHN), involvement of visceral organs, encephalitis and death.
Methods: We retrospectively analyzed solid OTR who have developed HZ in between December 2018 and December 2019. Medical records were reviewed to assess the clinical characteristics and outcome of HZ in those patients. Additionally, patients with severe pain who had required opioid analgesics and/or gabapentin were called back for follow up examination.
Results: There were 16 patients (Eight males and eight females) with a mean age of 43 (range, 11-58 years). Thirteen (81%) patients were renal transplant recipients, whereas three (19%) were cardiac transplant recipients. Median time from organ transplantation to onset of HZ was 39.5 months (range, 5.4-254.6 months).  Visceral disease or mortality did not occur in any of the patients. Most common (69%) complaint was pain. Four patients (25%) were asymptomatic, and presented only with skin lesions.  Thoracic region (9 patients) was the most common localization followed by genital-gluteal (4 patients), lower extremity (one patient), and ophthalmic region (one patient). Vesicles (75%) were the most common clinical presentation. Distribution of lesions was in single dermatome in 13 (81%) patients. One patient additionally had scattered vesicles adjacent to the primary dermatome, and two had scattered vesicles (<20) distant to the primary dermatome. Nine (56%) patients had received rejection treatment before the diagnosis of HZ. Majority (87.5%) of patients were on triple immunosuppressive regimen at the onset of HZ. For the treatment of HZ, four (%25) patients received outpatient treatment with oral valacyclovir therapy. Ten (62.5%) patients were hospitalized for the first few days (due to renal dysfunction, severe skin lesions, presence of lesions outside the primary dermatome, severe pain, or living out-of-town), and continued with oral antiviral therapy when discharged. One renal transplant patient with ophthalmic HZ and one cardiac transplant patient with hypoxic brain injury completed the antiviral treatment (intravenous acyclovir) in hospital. Renal dose adjustment was done in 8 (50%) patients. The doses of immunosuppressive drugs were reduced only in two cardiac transplant patients. Although 8 (%50) patients required potent analgesic treatment including opioid analgesics and/or gabapentin in the acute phase, only one that had ophthalmic HZ developed PHN. Among patients with severe pain, the longest duration of pain was 1.5 months. The patient with ophthalmic HZ later presented with transient third and sixth cranial nerve palsy without venous thrombosis and brain involvement.
Conclusion: With prompt initiation of patient-adjusted therapy, post-transplant HZ seems most likely to have a favorable course. Prospective studies including large number of OTR and immunocompetent individuals with HZ are needed.