COVID-19 ASSOCIATED REACTIVATION OF HERPES INFECTION WITH THE DEVELOPMENT OF ENCEPHALITIS: A CASE REPORT.

The etiology of meningoencephalitis with COVID19 is coronavirus and herpetic. Secondary herpes infection is associated with immunological dysregulation or with the use of tocilizumab. Differential diagnosis of the etiology of encephalitis is important, because acyclovir is effective for herpes infection. Case Report: A 38-year-old man with right-sided lower lobe pneumonia COVID-19 was hospitalized in the infectious diseases department. On the 6th day of hospitalization, the patient developed respiratory failure and was transferred to the anesthesiology and intensive care unit. We started noninvasive lung ventilation, which was ineffective, and the patient was intubated and started on MVL. MRI data: encephalitis of the frontal, parietal and occipital lobes on the left. On the 14th day, we detected a herpetic rash on the legs and thighs in the projection of the sciatic nerve. We suspected the patient had a herpes infection and prescribed acyclovir 1000 mg intravenously 3 times a day. On the 32nd day, a blood test by IFA revealed class G antibodies to the Viral Capsid Antigen (VCA) of the Epstein-Barr virus. On the 58th day, he was discharged home in a satisfactory condition. Given the extraordinary strain on healthcare systems amid the pandemic, there are challenges in diagnosing herpes infection in patients with COVID-19. The alertness of doctors about the development of herpes infection and its clinical signs is important. This will allow for early antiherpetic treatment.

Diagnosis and management of a herpes nipple infection that resulted in neonatal HSV encephalitis.

We present a case of a primigravida in her 30s who had a caesarean delivery of dichorionic diamniotic twins at 33 weeks of gestation. Her postpartum course was complicated by a herpes simplex virus (HSV) infection of her nipple, found after her neonates were diagnosed with HSV encephalitis. She was evaluated at her 3-week postpartum visit and reported that her neonates were concurrently admitted to the neonatal intensive care unit with disseminated neonatal HSV-1. The patient and her partner were in a monogamous relationship with no known history of HSV. Physical examination demonstrated a vertical fissure on the face of her right nipple and a small cluster of vesicles on her left hand. PCR swabs of the lesions were positive for HSV-1 at both locations. The patient was started on oral valacyclovir 1000 mg two times per day, topical acyclovir ointment applied 4-6 times per day and mupirocin ointment applied 3 times per day to her breast with resolution of her breast lesions. She was able to continue expressing her breastmilk with the help of a pump and then resumed breastfeeding once her infection was cleared. Her infants recovered after prolonged parenteral antiviral therapy with age-appropriate development at follow-up.

A case report: recurrent anemia related to long term acyclovir use in a pregnant HIV infected Ugandan.

This case report describes a pregnant patient with recent diagnosis of Human Immuno-Deficiency Virus (HIV) infection initiated on Anti-Retroviral Therapy (ART) in the second trimester, as well as high dose acyclovir high for large infected genital warts. She had no other HIV related opportunistic infections, and no prior anti tuberculosis treatment or preventive medication. Despite little response to acyclovir, patient was continuing on acyclovir for over 4 months. She subsequently developed recurrent anemia requiring frequent transfusion (14 units in total) over a 6-week period. On stopping acyclovir, the anemia subsided, a few weeks later she had a normal delivery, followed by surgical removal of the warts. At a follow-up 8 months later, she was well, with a healthy baby, and reported no other episodes of blood transfusion.

Varicella-Zoster Virus Reactivation After Pediatric Allogeneic Hematopoietic Stem Cell Transplantation, Single-Center Experience of Acyclovir Prophylaxis.

BACKGROUND: Varicella-zoster virus (VZV) reactivation is the most common infectious complication in the late posthematopoietic stem cell transplantation (HSCT) period and is reported as 16%-41%. Acyclovir prophylaxis is recommended for at least 1 year after HSCT to prevent VZV infections. However, studies on the most appropriate prophylaxis are ongoing in pediatric patients. METHODS: Patients who underwent allogeneic HSCT between January 1, 1996 and January 1, 2020 were retrospectively analyzed to outline the characteristics of VZV reactivation after allogeneic HSCT in pediatric patients using 6 months acyclovir prophylaxis. RESULTS: There were 260 patients and 273 HSCTs. Median age was 10.43 (0.47-18.38), and 56% was male. Median follow-up was 2325 days (18-7579 days). VZV reactivation occurred in 21.2% (n = 58) at a median of 354 (55-3433) days post-HSCT. The peak incidence was 6-12 months post-HSCT (43.1%). Older age at HSCT, female gender, history of varicella infection, lack of varicella vaccination, low lymphocyte, CD4 count, and CD4/CD8 ratio at 9 and 12 months post-HSCT was found as a significant risk for herpes zoster (HZ) in univariate analysis, whereas history of varicella infection and low CD4/CD8 ratio at 12 months post-HSCT was an independent risk factor in multivariate analysis. CONCLUSIONS: Tailoring acyclovir prophylaxis according to pre-HCT varicella history, posttransplant CD4 T lymphocyte counts and functions, and ongoing immunosuppression may help to reduce HZ-related morbidity and mortality.

Clinical characteristics and outcomes of patients with Herpes Simplex Encephalitis in Vietnam: a retrospective study.

BACKGROUND: Herpes simplex encephalitis (HSE) is an important central nervous infection with severe neurological sequelae. The aim of this study was to describe clinical characteristic and outcomes of patients with HSE in Vietnam. METHODS: This was a retrospective study of 66 patients with herpes simplex encephalitis who admitted to the National Hospital for Tropical Diseases, Hanoi, Vietnam from 2018 to 2021. The detection of herpes simplex virus (HSV) in cerebrospinal fluid was made by the real-time PCR assay. We reported the clinical manifestation on admission and evaluated clinical outcomes at the hospital discharge by modified Rankin Scale (mRS). Multivariate logistic regression analysis was used to analyze the independent risk factors of severe outcomes. RESULTS: Of the 66 patients with laboratory confirmed HSE, the median age was 53 years (IQR 38-60) and 44 patients (69.7%) were male. The most common manifestations included fever (100%), followed by the consciousness disorder (95.5%). Other neurological manifestation were seizures (36.4%), memory disorders (31.8%), language disorders (19.7%) and behavioral disorders (13.6%). Conventional magnetic resonance imaging (MRI) showed 93.8% patients with temporal lobe lesions, followed by abnormalities in insula (50%), frontal lobe (34.4%) and 48.4% of patients had bilateral lesions. At discharge, 19 patients (28.8%) completely recovered, 15 patients (22.7%) had mild sequelae, 28 patients (42.4%) had moderate to severe sequelae. Severe neurological sequelae were memory disorders (55.8%), movement disorders (53.5%), language disorders (30.2%). Multivariate logistic regression analysis showed that Glasgow score decrement at admission, seizures, and time duration from onset of symptoms to the start of Acyclovir treatment > 4 days were independent factors associated with severe outcomes in HSE patients. CONCLUSION: Glasgow score decrement, seizures and delay treatment with Acyclovir were associated with the poor outcome of patients with HSE.

Acyclovir extravasation in a newborn: a case report.

OBJECTIVE: Extravasation of infused drugs is not a rare problem in medical practice. Acyclovir is a vesicant and an antiviral medication commonly used for young children. In the present study, we presented a neonate with soft tissue damage due to acyclovir extravasation. CASE REPORT: A female newborn (Iranian, Asian) with gestational age 37+2 weeks and breech presentation was born by Cesarean delivery from a mother with a recent history of Herpes simplex virus (HSV) infection (Yas Women's Hospital, Tehran, Iran). Intravenous administration of acyclovir was initiated through a peripheral catheter inserted on the dorsal side of the left hand. A few minutes after the second dose, the patient showed a diffused firm swelling, local discoloration, and induration in the dorsum of the hand. The peripheral catheter was removed immediately. Hyaluronidase was injected subcutaneously in five different regions around the catheterization site. Intermittent limb elevation and cold compression (for 10 minutes) were applied. Serial follow-ups and examinations were performed hourly to check limb inflammation, ischemia, and compartment syndrome. The limb swelling and discoloration significantly improved 4 hours after the second dose of hyaluronidase. CONCLUSION: Early diagnosis of acyclovir extravasation and immediate management could prevent severe complications in neonates. Further studies are needed to suggest a standard approach and treatment protocol for acyclovir extravasation.

Identification and characterization of Varicella Zoster Virus circular RNA in lytic infection.

This study investigates the role of circular RNAs (circRNAs) in the context of Varicella-Zoster Virus (VZV) lytic infection. We employ two sequencing technologies, short-read sequencing and long-read sequencing, following RNase R treatment on VZV-infected neuroblastoma cells to identify and characterize both cellular and viral circRNAs. Our large scanning analysis identifies and subsequent experiments confirm 200 VZV circRNAs. Moreover, we discover numerous VZV latency-associated transcripts (VLTs)-like circRNAs (circVLTslytic), which contain multiple exons and different isoforms within the same back-splicing breakpoint. To understand the functional significance of these circVLTslytic, we utilize the Bacteria Artificial Chromosome system to disrupt the expression of viral circRNAs in genomic DNA location. We reveal that the sequence flanking circVLTs' 5' splice donor plays a pivotal role as a cis-acting element in the formation of circVLTslytic. The circVLTslytic is dispensable for VZV replication, but the mutation downstream of circVLTslytic exon 5 leads to increased acyclovir sensitivity in VZV infection models. This suggests that circVLTslytic may have a role in modulating the sensitivity to antiviral treatment. The findings shed new insight into the regulation of cellular and viral transcription during VZV lytic infection, emphasizing the intricate interplay between circRNAs and viral processes.

CRISPR/Cas9-mediated genome editing of the thymidine kinase gene in a clinical HSV-1 isolate identifies F289S as novel acyclovir-resistant mutation.

Herpes simplex virus type 1 (HSV-1) is a neurotropic alphaherpesvirus that establishes a lifelong infection in sensory neurons of infected individuals, accompanied with intermittent reactivation of latent virus causing (a)symptomatic virus shedding. Whereas acyclovir (ACV) is a safe and highly effective antiviral to treat HSV-1 infections, long-term usage can lead to emergence of ACV resistant (ACVR) HSV-1 and subsequently ACV refractory disease. Here, we isolated an HSV-1 strain from a patient with reactivated herpetic eye disease that did not respond to ACV treatment. The isolate carried a novel non-synonymous F289S mutation in the viral UL23 gene encoding the thymidine kinase (TK) protein. Because ACV needs conversion by viral TK and subsequently cellular kinases to inhibit HSV-1 replication, the UL23 gene is commonly mutated in ACVR HSV-1 strains. The potential role of the F289S mutation causing ACVR was investigated using CRISPR/Cas9-mediated HSV-1 genome editing. Reverting the F289S mutation in the original clinical isolate to the wild-type sequence S289F resulted in an ACV-sensitive (ACVS) phenotype, and introduction of the F289S substitution in an ACVS HSV-1 reference strain led to an ACVR phenotype. In summary, we identified a new HSV-1 TK mutation in the eye of a patient with ACV refractory herpetic eye disease, which was identified as the causative ACVR mutation with the aid of CRISPR/Cas9-mediated genome engineering technology. Direct editing of clinical HSV-1 isolates by CRISPR/Cas9 is a powerful strategy to assess whether single residue substitutions are causative to a clinical ACVR phenotype.

Antiviral medications for preventing cytomegalovirus disease in solid organ transplant recipients.

BACKGROUND: The risk of cytomegalovirus (CMV) infection in solid organ transplant recipients has resulted in the frequent use of prophylaxis to prevent the clinical syndrome associated with CMV infection. This is an update of a review first published in 2005 and updated in 2008 and 2013. OBJECTIVES: To determine the benefits and harms of antiviral medications to prevent CMV disease and all-cause death in solid organ transplant recipients. SEARCH METHODS: We contacted the information specialist and searched the Cochrane Kidney and Transplant Register of Studies up to 5 February 2024 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs comparing antiviral medications with placebo or no treatment, comparing different antiviral medications or different regimens of the same antiviral medications for CMV prophylaxis in recipients of any solid organ transplant. Studies examining pre-emptive therapy for CMV infection are studied in a separate review and were excluded from this review. DATA COLLECTION AND ANALYSIS: Two authors independently assessed study eligibility, risk of bias and extracted data. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS: This 2024 update found four new studies, bringing the total number of included studies to 41 (5054 participants). The risk of bias was high or unclear across most studies, with a low risk of bias for sequence generation (12), allocation concealment (12), blinding (11) and selective outcome reporting (9) in fewer studies. There is high-certainty evidence that prophylaxis with aciclovir, ganciclovir or valaciclovir compared with placebo or no treatment is more effective in preventing CMV disease (19 studies: RR 0.42, 95% CI 0.34 to 0.52), all-cause death (17 studies: RR 0.63, 95% CI 0.43 to 0.92), and CMV infection (17 studies: RR 0.61, 95% CI 0.48 to 0.77). There is moderate-certainty evidence that prophylaxis probably reduces death from CMV disease (7 studies: RR 0.26, 95% CI 0.08 to 0.78). Prophylaxis reduces the risk of herpes simplex and herpes zoster disease, bacterial and protozoal infections but probably makes little to no difference to fungal infection, acute rejection or graft loss. No apparent differences in adverse events with aciclovir, ganciclovir or valaciclovir compared with placebo or no treatment were found. There is high certainty evidence that ganciclovir, when compared with aciclovir, is more effective in preventing CMV disease (7 studies: RR 0.37, 95% CI 0.23 to 0.60). There may be little to no difference in any outcome between valganciclovir and IV ganciclovir compared with oral ganciclovir (low certainty evidence). The efficacy and adverse effects of valganciclovir or ganciclovir were probably no different to valaciclovir in three studies (moderate certainty evidence). There is moderate certainty evidence that extended duration prophylaxis probably reduces the risk of CMV disease compared with three months of therapy (2 studies: RR 0.20, 95% CI 0.12 to 0.35), with probably little to no difference in rates of adverse events. Low certainty evidence suggests that 450 mg/day valganciclovir compared with 900 mg/day valganciclovir results in little to no difference in all-cause death, CMV infection, acute rejection, and graft loss (no information on adverse events). Maribavir may increase CMV infection compared with ganciclovir (1 study: RR 1.34, 95% CI: 1.10 to 1.65; moderate certainty evidence); however, little to no difference between the two treatments were found for CMV disease, all-cause death, acute rejection, and adverse events at six months (low certainty evidence). AUTHORS' CONCLUSIONS: Prophylaxis with antiviral medications reduces CMV disease and CMV-associated death, compared with placebo or no treatment, in solid organ transplant recipients. These data support the continued routine use of antiviral prophylaxis in CMV-positive recipients and CMV-negative recipients of CMV-positive organ transplants.

Ramsay Hunt syndrome in atopic dermatitis patient treated with dupilumab.

The Ramsay-Hunt syndrome results from reactivation of the varicella-zoster virus at the geniculate ganglion level. The syndrome is characterized by a combination of symptoms such as ipsilateral facial paralysis, otalgia, and vesicles near the ear and auditory canal. The gold standard in the treatment of Ramsay-Hunt syndrome remains the combination of antiviral therapy with corticosteroids and adequate analgesic therapy. We present a case of a 45-year-old patient with severe form of atopic dermatitis, who developed this syndrome during treatment with dupilumab. The risks and benefits of dupilumab treatment in this patient were considered. Because both bronchial asthma and atopic dermatitis worsened when dupilumab was discontinued, it was indicated to continue this therapy with low-dose of acyclovir.

Commercial human 3D corneal epithelial equivalents for modeling epithelial infection in herpes keratitis.

Herpes stromal keratitis is the leading cause of infectious blindness in the western world. Infection by HSV1 is most common, but VZV and hCMV also infect the cornea. Multiple models of HSV1 corneal infection exist, but none for VZV and hCMV because of their host specificity. Here, we used commercially available 3D human corneal epithelial equivalents (HCEE) to study infection by these herpesviruses. HCEE was infected by HSV-1 and hCMV without requiring scarification and resulted in spreading infections. Spread of HSV-1 infection was rapid, while that of hCMV was slow. In contrast, infections with VZV required damage to the HCEE and did not spread. Acyclovir dramatically reduced replication of HSV-1 in this model. We conclude that highly quality-controlled, readily available HCEE is a useful model to study human-restricted herpesvirus infection of the human corneal epithelium and for screening of antiviral drugs for treating HSK in an 3D model system.

Computational analysis of antiviral drugs using topological descriptors.

Many health challenges are attributed to viral infections, which represent significant concerns in public health. Among these infections, diseases such as herpes simplex virus (HSV), cytomegalovirus (CMV), and varicella-zoster virus (VZV) infections have garnered attention due to their prevalence and impact on human health. There are specific antiviral medications available for the treatment of these viral infections. Drugs like Cidofovir, Valacyclovir, and Acyclovir are commonly prescribed. These antiviral drugs are known for their efficacy against herpesviruses and related viral infections, leveraging their ability to inhibit viral DNA polymerase. A molecular descriptor is a numerical value that correlates with specific physicochemical properties of a molecular graph. This article explores the calculation of distance-based topological descriptors, including the Trinajstic, Mostar, Szeged, and PI descriptors for the aforementioned antiviral drugs. These descriptors provide insights into these drugs' structural and physicochemical characteristics, aiding in understanding their mechanism of action and the development of new therapeutic agents.

Harmol used for the treatment of herpes simplex virus induced keratitis.

Herpes simplex virus type 1 (HSV-1) infection of the eyes results in herpes simplex keratitis (HSK), which has led to vision loss and even blindness in patients. However, the rate of drug resistance in HSV is on the rise; therefore, new antiviral agents with sufficient safety profiles must be developed. At present, we assessed the anti-HSV-1 activity of 502 natural compounds and their ability to reduce the HSV-1-induced cytopathic effect. We chose harmol for further studies because it exhibited the highest antiviral activity. We found that harmol inhibited both HSV-1 F and HSV-1/153 (a clinical drug-resistant strain) replication, with an EC50 of 9.34 µM and 5.84 µM, respectively. Moreover, harmol reduced HSV-1 replication in corneal tissues and viral progeny production in tears, and also alleviated early corneal surface lesions related to HSK. For example, harmol treatment preserved corneal thickness and nerve density in HSK mice. Interestingly, harmol also showed a promising antiviral effect on HSV-1/153 induced HSK in mouse model. Furthermore, harmol combined with acyclovir (ACV) treatment showed a greater antiviral effect than either one alone in vitro. Therefore, harmol may be a promising therapeutic agent for managing HSK.

Remission of HPV-Related Diseases by Antivirals for Herpesvirus: Clinical Cases and a Literature Review.

Epidemiological studies have shown that HPV-related diseases are the most prevalent sexually transmitted infections. In this context, this report will present various clinical cases demonstrating the effectiveness of Acyclovir (ACV) or its prodrug Valaciclovir (VCV), both acyclic guanosine analogs commonly used for the treatment of HHV-1 and HHV-2, for the treatment of HPV-related diseases. The report shows the remission of five cases of penile condyloma and a case of remission in a woman affected by cervical and vaginal condylomas and a vulvar giant condyloma acuminate of Buschke and Lowenstein. The literature review shows that ACV is effective in treating skin warts when administered orally, topically, and intralesionally, suggesting its therapeutic potential in other diseases associated with HPV. ACV was also used successfully as an adjuvant therapy for juvenile and adult forms of laryngeal papillomatosis, also known as recurrent respiratory papillomatosis, prolonging the patient's symptom-free periods. Although the prevention of HPV infections is certainly achieved with the HPV vaccine, ACV and VCV have shown to be effective even against genotypes not included in the current vaccine and can be helpful for those problematic clinical cases involving unvaccinated individuals, immunocompromised patients, people who live with HIV, or non-responders to the vaccine. We and others concluded that randomized clinical trials are necessary to determine the efficacy of ACV and VCV for HPV-related diseases.

Clinical features of atypical presentations of mucocutaneous herpes simplex virus infection observed in immunosuppressed individuals. Part II: the knife-cut sign.

The knife-cut sign is a distinctive manifestation of herpes simplex virus (HSV) type 1 or HSV type 2 infection that has been described in at least 10 immunocompromised patients. It appears as an extremely painful linear erosion or fissure in an intertriginous area such as the body folds beneath the breast, or within the abdomen, or in the inguinal region. Also, concurrent HSV infection at other mucocutaneous sites, or viscera, or both have been observed. The patients had medical conditions (at least 9 patients) and/or immunosuppressive drug therapy (6 patients). The diagnosis of HSV infection was confirmed by viral culture (8 patients), biopsy (4 patients), direct fluorescence antibody testing (3 patients), immunohistochemistry staining (2 patients), polymerase chain reaction (2 patients), or Western blot serologic assay (1 patient). Knife-cut sign-associated HSV infection is potentially fatal; three patients died. However, clinical improvement or complete healing occurred in the patients who received oral valacyclovir (1 patient), or intravenous acyclovir (2 patients), or intravenous acyclovir followed by foscarnet (1 patient). In summary, HSV infection associated with a positive the knife-cut sign is a potentially fatal variant of HSV infection that occurs in the intertriginous areas of immunocompromised patients and usually requires intravenous antiviral therapy.

Clinical features of atypical presentations of mucocutaneous herpes simplex virus infection observed in immunosuppressed individuals. Part I: herpetic geometric glossitis.

Herpetic geometric glossitis is a unique morphologic variant of HSV (herpes simplex virus) type 1 infection on the dorsum of the tongue that presents as an extremely painful linear central lingual fissure with a branched pattern. in the center of the tongue; there is a branched pattern of fissures that extend bilaterally from the central linear fissure. Herpetic geometric glossitis has been reported in 11 patients; 8 of these individuals were immunocompromised. Medical conditions and immunosuppressive medication treatment (7 patients) or only medical disorders (3 patients) or neither (1 patient) were present. HSV type 1 infection was diagnosed by viral culture in (7 patients), Tzanck preparation (2 patients) or clinically (2 patients). Mucocutaneous HSV infection at non-lingual locations--including the lips, labial mucosa, face and chest--were observed in 5 patients. All patients' symptoms and lesions responded to treatment with oral antiviral therapy: acyclovir (9 patients), famciclovir (1 patient) or valacyclovir (1 patient). The lingual pain and dorsal tongue fissures completely resolved completely within two to 14 days. In summary, herpetic geometric glossitis is a unique HSV type 1 infection, usually in immunocompromised patients, that occurs on the dorsal tongue and responds completely after treatment with orally administered antiviral therapy.

Serious neurological adverse events in immunocompetent children and adolescents caused by viral reactivation in the years following varicella vaccination.

Serious adverse events following vaccination include medical complications that require hospitalisation. The live varicella vaccine that was approved by the Food and Drug Administration in the United States in 1995 has an excellent safety record. Since the vaccine is a live virus, adverse events are more common in immunocompromised children who are vaccinated inadvertently. This review includes only serious adverse events in children considered to be immunocompetent. The serious adverse event called varicella vaccine meningitis was first reported in a hospitalised immunocompetent child in 2008. When we carried out a literature search, we found 15 cases of immunocompetent children and adolescents with varicella vaccine meningitis; the median age was 11 years. Eight of the children had received two varicella vaccinations. Most of the children also had a concomitant herpes zoster rash, although three did not. The children lived in the United States, Greece, Germany, Switzerland, and Japan. During our literature search, we found five additional cases of serious neurological events in immunocompetent children; these included 4 cases of progressive herpes zoster and one case of acute retinitis. Pulses of enteral corticosteroids as well as a lack of herpes simplex virus antibody may be risk factors for reactivation in immunocompetent children. All 20 children with adverse events were treated with acyclovir and recovered; 19 were hospitalised and one child was managed as an outpatient. Even though the number of neurological adverse events remains exceedingly low following varicella vaccination, we recommend documentation of those caused by the vaccine virus.

Valacyclovir or valganciclovir for cytomegalovirus prophylaxis: A randomized controlled trial in adult and pediatric kidney transplant recipients.

BACKGROUND: Valganciclovir (valG), a cytomegalovirus (CMV) prophylactic agent, has dose-limiting side effects. The tolerability and effectiveness of valacyclovir (valA) as CMV prophylaxis is unknown. METHODS: We conducted a randomized, open-label, single-center trial of valA versus valG for all posttransplant CMV prophylaxis in adult and pediatric kidney recipients. Participants were randomly assigned to receive valA or valG. Primary endpoints were the incidence of CMV viremia and side-effect related drug reduction with secondary assessment of incidence of EBV viremia. RESULTS: Of the 137 sequential kidney transplant recipients enrolled, 26 % were positive and negative for CMV antibody in donor and recipient respectively. The incidence of CMV viremia (4 of 71 [6 %]; 8 of 67 [12 %] P = 0.23), time to viremia (P = 0.16) and area under CMV viral load time curve (P = 0.19) were not significantly different. ValG participants were significantly more likely to require side-effect related dose reduction (15/71 [21 %] versus 1/66 [2 %] P = 0.0003). Leukopenia was the most common reason for valG dose reduction and granulocyte-colony stimulating factor was utilized for leukopenia recovery more frequently (25 % in valG vs 5 % in valA: P = 0.0007). Incidence of EBV viremia was not significantly different. CONCLUSIONS: ValA has significantly less dose-limiting side effects than valG. In our study population, a significant increase in CMV viremia was not observed, in adults and children after kidney transplant, compared to valG. TRIAL REGISTRATION NUMBER: NCT01329185.