Acute kidney injury due to acyclovir

Application of hydrogel microneedles in the oral cavity

Microneedles are a transdermal drug delivery system in which the needle punctures the epithelium to deliver the drug directly to deep tissues, thus avoiding the influence of the first-pass effect of the gastrointestinal tract and minimizing the likelihood of pain induction. Hydrogel microneedles are microneedles prepared from hydrogels that have good biocompatibility, controllable mechanical properties, and controllable drug release and can be modified to achieve environmental control of drug release in vivo. The large epithelial tissue in the oral cavity is an ideal site for drug delivery via microneedles. Hydrogel microneedles can overcome mucosal hindrances to delivering drugs to deep tissues; this prevents humidity and a highly dynamic environment in the oral cavity from influencing the efficacy of the drugs and enables them to obtain better therapeutic effects. This article analyzes the materials and advantages of common hydrogel microneedles and reviews the application of hydrogel microneedles in the oral cavity.

Evaluation of the stability of aciclovir in elastomeric infusion devices used for outpatient parenteral antimicrobial therapy

OBJECTIVES

To investigate the stability of aciclovir solutions in elastomeric devices used for outpatient parenteral antimicrobial therapy (OPAT).

METHODS

Triplicates of two elastomeric devices, Accufuser and Easypump II, were filled with a solution of 200 mg, 2400 mg, and 4500 mg aciclovir in 240 mL 0.9% w/v saline. Devices were stored at room temperature for 14 days, followed by 24 hours storage at 32°C. Assessment using a stability indicating assay, pH and subvisible particle analysis was undertaken at 11 time points throughout the study.

RESULTS

Aciclovir solution at 200 mg and 2400 mg in 240 mL was stable for 14 days at room temperature (<20°C) and 24 hours of 32°C 'in-use' temperature exposure, remaining above the 95% limit for NHS stability protocols. The high dose was also stable for 14 days at room temperature, but when stored at 32°C there was precipitation of aciclovir within 4 hours in both devices. The precipitate was confirmed as aciclovir and precipitation was not a sign of chemical degradation.

CONCLUSIONS

Aciclovir concentrations above 2400 mg/240 mL are liable to precipitation and cannot be recommended for OPAT services because of heightened risks of nephrotoxicity. Aciclovir solution can be given as a continuous 24-hour infusion for OPAT services at a concentration range of 200-2400 mg in 240 mL in Accufuser and Easypump II elastomeric devices following 14 days storage at room temperature, protected from light.

Acyclovir-Induced Nephrotoxicity and Neurotoxicity: A Report of Two Cases

Acyclovir is a widely used antiviral agent used to treat viral meningitis. Although well tolerated, on rare occasions, it can cause severe nephrotoxicity and neurotoxicity. It is recommended that the dose of intravenous acyclovir be calculated based on the ideal body weight for height rather than the actual weight in obese patients to avoid excessive dosage. We report two patients who developed severe acute kidney injury and neurological symptoms while on intravenous acyclovir therapy. The first patient was a 57-year-old obese woman known to have epilepsy who received a dose of intravenous acyclovir based on her actual weight of 80 kg and subsequently developed acyclovir-induced nephrotoxicity and increased seizure activity. The second patient was a 60-year-old, slightly overweight, man, who received a dose of intravenous acyclovir based on his actual weight of 80 kg and subsequently developed both acyclovir-induced nephrotoxicity and possible neurotoxicity. No other cause for the deterioration in renal function or neurological symptoms was identified, and there was rapid recovery within three days of stopping acyclovir therapy. This case report emphasizes the importance of monitoring renal function while patients are on intravenous acyclovir therapy and highlights the fact that even non-obese, overweight patients are at risk of toxicity when their actual body weight instead of their ideal body weight for height is used for intravenous acyclovir dose calculation.

The Interplay of Genital Herpes with Cellular Processes: A Pathogenesis and Therapeutic Perspective

Genital herpes, primarily caused by herpes simplex virus-2 (HSV-2), remains a pressing global health concern. Its remarkable ability to intertwine with cellular processes, from harnessing host machinery for replication to subverting antiviral defenses like autophagy and programmed cell death, exemplifies the intricate interplay at the heart of its pathogenesis. While the biomedical community has extensively researched antiviral interventions, the efficiency of these strategies in managing HSV-2 remains suboptimal. Recognizing this, attention has shifted toward leveraging host cellular components to regulate HSV-2 replication and influence the cell cycle. Furthermore, innovative interventional strategies-including drug repurposing, microbivacs, connecting the host microbiome, and exploiting natural secondary metabolites-are emerging as potential game changers. This review summarizes the key steps in HSV-2 pathogenesis and newly discovered cellular interactions, presenting the latest developments in the field, highlighting existing challenges, and offering a fresh perspective on HSV-2's pathogenesis and the potential avenues for its treatment by targeting cellular proteins and pathways.

In-silico studies on wild orange (Citrus macroptera Mont.) compounds against COVID-19 pro-inflammation targets

One-fifth of COVID-19 patients suffer a severe course of COVID-19 (SARS-CoV-2) infection; however, the specific causes remain unclear. Despite numerous papers that have been flooded in different scientific journals clear clinical picture of COVID-19 aftermath persists to remain fuzzy. The survivors of severe COVID-19infection having defeated the virus are just the starting of an uncharted recovery path. Currently, there is no drug available that is safe to consume to combat this pandemic. However, researchers still struggling to find specific therapeutic solutions. The present study employed an in silico approach to assessing the inhibitory potential of the phytochemicals obtained from GC-MS analysis of Citrus macroptera against inflammatory proteins like COX-2, NMDAR and VCAM-1 which remains in a hyperactive state even after a patient is fully cured of this deadly mRNA virus. An extensive molecular docking investigation of the phyto-compounds at the active binding pockets of the inflammatory proteins revealed the promising inhibitory potential of the phytochemicals. Reasonable physicochemical attributes of the compounds following Lipinski's rule of five, VEBER and PAINS analysis further established them as potential therapeutic candidates against aforesaid inflammatory proteins. MM-GBSA binding free energy estimation revealed that Limonene was the most promising candidate displaying the highest binding efficacy with the concerned VCAM-1 protein included in the present analysis. An interesting finding is the phytochemicals exhibited better binding energy scores with the concerned COX-2, VCAM-1 and NMDA receptor proteins than the conventional drugs that are specifically targeted against them. Our in silico results suggest that all the natural phyto-compounds derived from C. macroptera could be employed in Post covid inflammation complexities after appropriate pre-clinical and clinical trials for further scientific validation.Communicated by Ramaswamy H. Sarma.

Valacyclovir-associated acute kidney injury and encephalopathy in an elderly woman with normal kidney function: a case report

A 72-year-old Japanese woman was treated by 3000 mg/day of valacyclovir for the herpes zoster in her left back. She had been treated as hypertension with no renal insufficiency. In two days, she visited an emergency room of a regional stroke care center with dysarthria, dexterity disorder and gait disturbance. Neither head CT nor MRI found intracranial lesions, then, laboratory tests revealed that her serum creatinine level was 4.63 mg/dL. She was transferred and admitted to our hospital on the following day and received hemodialysis under the diagnosis of AKI due to acyclovir accompanied with encephalopathy. Afterward, her serum concentration of acyclovir revealed as 44 μg/mL, which is extremely high. Her neurological symptom disappeared in parallel with the decrease of serum concentration of acyclovir. She received 3 sessions of hemodialysis and discharged on the 8th day of admission with almost normal renal function and no neurological sequela.

Safety, efficacy and delivery of multiple nucleoside analogs via drug encapsulated carbon (DECON) based sustained drug release platform

Acyclovir and similar nucleoside analogs form an essential frontline treatment for various herpesvirus infections of the eye. However, these drugs have low ocular retention when delivered topically and need to be administered several times every day. We have previously demonstrated that acyclovir loaded into activated carbon can be used to significantly decrease dosage frequency in a murine model of ocular infection. In this study, we demonstrate that other nucleoside analogs such as ganciclovir, penciclovir and famciclovir have excellent loading and release profile similar to acyclovir. Similarly we also demonstrate that nucleoside analog loaded carbons termed DECON are effective at very low concentrations in treating active viral infection of human corneal epithelial cells. In this study, using a variety of techniques to evaluate corneal dryness, nerve sensitivity, intraocular pressure, corneal thickness, and somatic inflammation, we report that DECON is well tolerated after administration three times daily over the course of four weeks.

Incidence, patterns, risk factors and clinical outcomes of intravenous acyclovir induced nephrotoxicity

Objectives

Acyclovir is approved to treat herpes simplex virus (HSV) type 1, type 2 and varicella-zoster virus. It is mainly eliminated via the kidneys, for which drug crystals accumulation might lead to nephrotoxicity. This study aimed to determine the incidence, risk factors, preventive measures, and clinical outcomes of acyclovir induced-nephrotoxicity.

Methods

This is a retrospective cohort study of patients >12 years of age at Sultan Qaboos University Hospital (SQUH) receiving IV acyclovir therapy between January 2016 and December 2020.

Results

Out of 191 included patients, 40 (20.1%) developed acyclovir induced-nephrotoxicity. Age (per year older: OR 1.04, 95 %CI 1.01–1.07), total duration of treatment (per day OR1.19, 95 %CI 1.06–1.33), and concomitant use of vancomycin (OR 5.96, 95 %CI 1.87–19.01) were significant independent risk factors for acyclovir induced-nephrotoxicity development. Nine patients (4.5%) died during the same hospitalization, including those three patients who required renal replacement therapy (1.5%).

Conclusion

Frequent monitoring of kidney function for older patients with concurrent use of vancomycin and IV hydration is essential to prevent IV acyclovir induced-nephrotoxicity. Antimicrobial stewardship is a crucial method to reduce the duration of treatment with IV acyclovir as appropriate.

Evaluation of Adverse Drug Reactions in Paediatric Patients: A Retrospective Study in Turkish Hospital

Drug safety in paediatric patients is a serious public health concern around the world. The paediatric patients are more prone to adverse drug reactions (ADRs) than adults. Moreover, there is a scarcity of information about ADRs in paediatric patients. This study was conducted to determine the frequency, causality, severity, preventability of paediatric patients’ ADRs reported in a tertiary care hospital in Adana, Turkey. A retrospective study was conducted on all spontaneously reported ADRs between January 01, 2020, to July 30, 2021, in paediatric patients. The ADRs reports were evaluated in terms of gender, age, ADR characteristics, suspected drugs and reporting source. All included ADRs reports were characterized according to the Naranjo Algorithm/World Health Organization (WHO) causality scales, Hartwig/Siegel and Common Terminology Criteria for Adverse Events (CTCAE) severity scales, the modified Schoumock and Thornton preventability scale and hospital pharmacovigilance center criteria for seriousness. Therapeutic groups were also coded using the WHO-Anatomical Therapeutic and Chemical (ATC) classification. During the study period, 8,912 paediatric patients who were admitted had 16 ADRs with 1.7 ADRs/1,000 admissions. The majority of ADRs were found in infants (31.2%) and children (56.2%) as compared to adolescents (12.5%). ADRs were observed more in females (81.2%) than males. Skin (62.5%) was the most affected organ due to the ADRs, and maculopapular rash and erythema multiforme were the most commonly reported symptoms. Most ADRs were probable/likely (93.7%), severe (50%), preventable or probably preventable (43.7%) and serious (37.5%). Antibiotics (93.7%) were found to be the most common cause of ADRs in paediatric patients. The majority of ADRs were associated with vancomycin (68.7%). Most of the ADRs were reported by a medical doctor in this study. This small sample size study highlights significant problems of ADRs in paediatric patients, mainly caused by antibiotics and with a majority of ADRs manifest as skin reactions. Furthermore, a high proportion of the identified ADRs were found to be preventable. More focused efforts are needed at the national level to avoid preventable ADRs in hospitals. Monitoring and management of ADRs and future studies would be beneficial for better patient care and safety.

Critical Review of Synthesis, Toxicology and Detection of Acyclovir

Acyclovir (ACV) is an effective and selective antiviral drug, and the study of its toxicology and the use of appropriate detection techniques to control its toxicity at safe levels are extremely important for medicine efforts and human health. This review discusses the mechanism driving ACV’s ability to inhibit viral coding, starting from its development and pharmacology. A comprehensive summary of the existing preparation methods and synthetic materials, such as 5-aminoimidazole-4-carboxamide, guanine and its derivatives, and other purine derivatives, is presented to elucidate the preparation of ACV in detail. In addition, it presents valuable analytical procedures for the toxicological studies of ACV, which are essential for human use and dosing. Analytical methods, including spectrophotometry, high performance liquid chromatography (HPLC), liquid chromatography/tandem mass spectrometry (LC-MS/MS), electrochemical sensors, molecularly imprinted polymers (MIPs), and flow injection–chemiluminescence (FI-CL) are also highlighted. A brief description of the characteristics of each of these methods is also presented. Finally, insight is provided for the development of ACV to drive further innovation of ACV in pharmaceutical applications. This review provides a comprehensive summary of the past life and future challenges of ACV.

Targeting COVID-19 (SARS-CoV-2) main protease through active phytocompounds of ayurvedic medicinal plants - Emblica officinalis (Amla), Phyllanthus niruri Linn. (Bhumi Amla) and Tinospora cordifolia (Giloy) - A molecular docking and simulation study

Coronavirus Disease-2019 (COVID-19), a viral disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was declared a global pandemic by WHO in 2020. In this scenario, SARS-CoV-2 main protease (COVID-19 M^pro), an enzyme mainly involved in viral replication and transcription is identified as a crucial target for drug discovery. Traditionally used medicinal plants contain a large amount of bioactives and pave a new path to develop drugs and medications for COVID-19. The present study was aimed to examine the potential of Emblica officinalis (amla), Phyllanthus niruri Linn. (bhumi amla) and Tinospora cordifolia (giloy) bioactive compounds to inhibit the enzymatic activity of COVID-19 M^pro. In total, 96 bioactive compounds were selected and docked with COVID-19 M^pro and further validated by molecular dynamics study. From the docking and molecular dynamics study, it was revealed that the bioactives namely amritoside, apigenin-6-C-glucosyl7-O-glucoside, pectolinarin and astragalin showed better binding affinities with COVID-19 M^pro. Drug-likeness, ADEMT and bioactivity score prediction of best drug candidates were evaluated by DruLiTo, pkCSM and Molinspiration servers, respectively. Overall, the in silico results confirmed that the validated bioactives could be exploited as promising COVID-19 M^pro inhibitors.

Pathobiology and treatment of viral keratitis

Keratitis is one of the most prevalent ocular diseases manifested by partial or total loss of vision. Amongst infectious (viz., microbes including bacteria, fungi, amebae, and viruses) and non-infectious (viz., eye trauma, chemical exposure, and ultraviolet exposure, contact lens) risk factors, viral keratitis has been demonstrated as one of the leading causes of corneal opacity. While many viruses have been shown to cause keratitis (such as rhabdoviruses, coxsackieviruses, etc.), herpesviruses are the predominant etiologic agent of viral keratitis. This chapter will summarize current knowledge on the prevalence, diagnosis, and pathobiology of viral keratitis. Virus-mediated immunomodulation of host innate and adaptive immune components is critical for viral persistence, and dysfunctional immune responses may cause destruction of ocular tissues leading to keratitis. Immunosuppressed or immunocompromised individuals may display recurring disease with pronounced severity. Early diagnosis of viral keratitis is beneficial for disease management and response to treatment. Finally, we have discussed current and emerging therapies to treat viral keratitis.

Elusive diagnosis of Behcet's disease in setting of painless vision loss

Behcet’s disease is a chronic, idiopathic vasculitis with multisystem involvement commonly characterized by the classic triad of oral lesions, genital ulcerations, and uveitis. We discuss the case of a 22-year-old woman with a long-standing history of oral ulcers and vulvovaginal burning who presented with acute painless uveitis. With this presentation, there was an initial concern for infectious retinitis for which she was started on systemic antiviral therapy. Subsequent infectious disease workup was ultimately negative. Given her medical history and current presentation, she was diagnosed and treated for an acute inflammatory episode of ocular Behcet’s disease. The patient’s vision returned to baseline prior to discharge after treatment with systemic glucocorticoids. The diagnosis of Behcet’s disease in the setting of painless vision loss can oftentimes be elusive. However, it is important for clinicians to keep this condition as a differential diagnosis in patients presenting with acute onset uveitis as the progression of Behcet’s disease can lead to severe vision loss and blindness without prompt and adequate treatment.

Infection-Induced Porcine Ex Vivo Corneal Wound Model to Study the Efficacy of Herpes Simplex Virus-1 Entry and Replication Inhibitors

Corneal infections by viruses and bacteria can result in ocular surface defects, ulcers, or wounds. Herpes simplex virus type-1 (HSV-1) is a human virus with global seroprevalence in the range of 60-90%. While the virus more commonly causes mucocutaneous lesions including ulcers on the face and mouth, it is also a leading cause of infection-associated blindness. In this chapter, we discuss an in-depth protocol required to evaluate corneal damage due to HSV-1 infection using porcine models of ex vivo infection. Our methods can be adapted to study similar infections caused by other viruses and bacteria.

Standalone or combinatorial phenylbutyrate therapy shows excellent antiviral activity and mimics CREB3 silencing

Herpesviruses are ubiquitous human pathogens that tightly regulate many cellular pathways including the unfolded protein response to endoplasmic reticulum (ER) stress. Pharmacological modulation of this pathway results in the inhibition of viral replication. In this study, we tested 4-phenylbutyrate (PBA), a chemical chaperone-based potent alleviator of ER stress, for its effects on herpes simplex virus (HSV) type 1 infection. Through in vitro studies, we observed that application of PBA to HSV-infected cells results in the down-regulation of a proviral, ER-localized host protein CREB3 and a resultant inhibition of viral protein synthesis. PBA treatment caused viral inhibition in cultured human corneas and human skin grafts as well as murine models of ocular and genital HSV infection. Thus, we propose that this drug can provide an alternative to current antivirals to treat both ocular HSV-1 and genital HSV-2 infections and may be a strong candidate for human trials.

Antiviral Agents for the Prevention and Treatment of Herpes Simplex Virus Type-1 Infection in Clinical Oncology: A Network Meta-Analysis

Cancer therapy may be complicated and compromised by viral infections, including oral herpes simplex virus (HSV) infection. This network meta-analysis aimed to identify the best antiviral agent to prevent or treat oral HSV infection in patients being treated for cancer. A search was conducted for trials published since inception until the 10th of May 2020 in MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials. A network meta-analysis was performed on the data from randomized controlled trials that assessed antiviral agents for preventive or therapeutic activity vs. placebo, no treatment or any other active intervention in patients being treated for cancer. The agents were ranked according to their effectiveness in the prevention of oral HSV using surface under the cumulative ranking (SUCRA). Grading of Recommendations, Assessment, Development and Evaluations (GRADE) was used to assess the certainty of the evidence. In total, 16 articles were included. The pooled relative risk (RR) to develop oral HSV infection in the acyclovir group was 0.17 (95% CI: 0.10, 0.30), compared to 0.22 (95% CI: 0.06, 0.77) in the valacyclovir group. Acyclovir ranked highest for the prevention of oral HSV followed by valacyclovir. Subgroup analysis with different acyclovir regimens revealed that the best regimens in terms of HSV-1 prevention were 750 mg/m2 acyclovir administered intravenously followed by 1600 mg per day orally. Acyclovir (250 mg/m2 per day) administered intravenously was the least effective against the prevention of oral HSV.

Herpes Zoster in Kidney Transplant Recipients: A Series of Three Cases

Kidney transplant recipients require lifelong immunosuppression to prevent organ rejection. The need for this intervention, however, leads to decreased cellular immunity and, in turn, increased risk of developing herpes zoster (HZ) from reactivation of latent varicella zoster virus. HZ commonly presents as a painful rash in a dermatome presentation followed by post-herpetic neuralgia. In immunosuppressed individuals, the presentation can be atypical and vary in severity depending on degree of immunosuppression and host immune response. We present the clinical course of 3 kidney transplant recipients who developed HZ after transplantation at different times post-transplant with varying clinical manifestations. The balance between maintaining immunosuppression and preventing or subsequently treating disseminated disease is discussed.

In Vitro and In Vivo Activity, Tolerability, and Mechanism of Action of BX795 as an Antiviral against Herpes Simplex Virus 2 Genital Infection

Herpes simplex virus type 2 (HSV-2) causes recurrent lesions in the anogenital area that may be transmitted through sexual encounters. Nucleoside analogs, such as acyclovir (ACV), are currently prescribed clinically to curb this infection. However, in some cases, reduced efficacy has been observed due to the emergence of resistance against these drugs. In our previous study, we reported the discovery of a novel anti-HSV-1 small molecule, BX795, which was originally used as an inhibitor of TANK-binding kinase 1 (TBK1). In this study, we report the antiviral efficacy of BX795 on HSV-2 infection in vaginal epithelial cells in vitro at 10 μM and in vivo at 50 μM. Additionally, through biochemical assays in vitro and histopathology in vivo, we show the tolerability of BX795 in vaginal epithelial cells at concentrations as high as 80 μM. Our investigations also revealed that the mechanism of action of BX795 antiviral activity stems from the reduction of viral protein translation via inhibition of protein kinase B phosphorylation. Finally, using a murine model of vaginal infection, we show that topical therapy using 50 μM BX795 is well tolerated and efficacious in controlling HSV-2 replication.

BX795 demonstrates potent antiviral benefits against herpes simplex Virus-1 infection of human cell lines

Herpes simplex virus-1 (HSV-1) infection is known to cause skin blisters, keratitis as well as deadly cases of encephalitis in some situations. Only a few therapeutic modalities are available for this globally prevalent infection. Very recently, a small molecule BX795 was identified as an inhibitor of HSV-1 protein synthesis in an ocular model of infection. In order to demonstrate its broader antiviral benefits, this study was aimed at evaluating the antiviral efficacy, mode-of-action, and toxicity of BX795 against HSV-1 infection of three human cell lines: HeLa, HEK, and HCE. Several different assays, including cell survival analysis, imaging, plaque analysis, Immunoblotting, and qRT-PCR, were performed. In all cases, BX795 demonstrated low toxicity at therapeutic concentration and showed strong antiviral benefits. Quite interestingly, cell line-dependent differences in the mechanism of antiviral action and cytokine response to infection were seen upon BX795 treatment. Taken together, our results suggest that BX795 may exert its antiviral benefits via cell-line specific mechanisms.

Kidney-based in vitro models for drug-induced toxicity testing

The kidney is frequently involved in adverse effects caused by exposure to foreign compounds, including drugs. An early prediction of those effects is crucial for allowing novel, safe drugs entering the market. Yet, in current pharmacotherapy, drug-induced nephrotoxicity accounts for up to 25% of the reported serious adverse effects, of which one-third is attributed to antimicrobials use. Adverse drug effects can be due to direct toxicity, for instance as a result of kidney-specific determinants, or indirectly by, e.g., vascular effects or crystals deposition. Currently used in vitro assays do not adequately predict in vivo observed effects, predominantly due to an inadequate preservation of the organs' microenvironment in the models applied. The kidney is highly complex, composed of a filter unit and a tubular segment, together containing over 20 different cell types. The tubular epithelium is highly polarized, and the maintenance of this polarity is critical for optimal functioning and response to environmental signals. Cell polarity is dependent on communication between cells, which includes paracrine and autocrine signals, as well as biomechanic and chemotactic processes. These processes all influence kidney cell proliferation, migration, and differentiation. For drug disposition studies, this microenvironment is essential for prediction of toxic responses. This review provides an overview of drug-induced injuries to the kidney, details on relevant and translational biomarkers, and advances in 3D cultures of human renal cells, including organoids and kidney-on-a-chip platforms.

Current and Emerging Therapies for Ocular Herpes Simplex Virus Type-1 Infections

Herpes simplex virus type-1 (HSV-1) is a neurotropic, double-stranded DNA virus that can cause a wide variety of diseases, including many ocular pathologies. It is one of the leading causes of infectious blindness in the United States. Because of its ubiquitous nature and its potential to cause serious ocular maladies, there is a significant need for more effective antiviral therapies against ocular HSV-1. In this review, we discuss the lifecycle of HSV-1 as it pertains to corneal infections and the clinically approved as well as emerging treatments to combat HSV-1 infections. We also highlight some newly identified host targets for the antiviral drug development.

An off-target effect of BX795 blocks herpes simplex virus type 1 infection of the eye

Herpes simplex virus type 1 (HSV-1) causes recurrent mucocutaneous lesions in the eye that may advance to corneal blindness. Nucleoside analogs exemplified by acyclovir (ACV) form the primary class of antiherpetic drugs, but this class suffers limitations due to the emergence of viral resistance and other side effects. While studying the molecular basis of ocular HSV-1 infection, we observed that BX795, a commonly used inhibitor of TANK-binding kinase 1 (TBK1), strongly suppressed infection by multiple strains of HSV-1 in transformed and primary human cells, cultured human and animal corneas, and a murine model of ocular infection. Our investigations revealed that the antiviral activity of BX795 relies on targeting Akt phosphorylation in infected cells, leading to the blockage of viral protein synthesis. This small-molecule inhibitor, which was also effective against an ACV-resistant HSV-1 strain, shows promise as an alternative to existing drugs and as an effective topical therapy for ocular herpes infection. Collectively, our results obtained using multiple infection models and virus strains establish BX795 as a promising lead compound for broad-spectrum antiviral applications in humans.

Risk Evaluation for Acute Kidney Injury Induced by the Concomitant Use of Valacyclovir, Analgesics, and Renin-Angiotensin System Inhibitors: The Detection of Signals of Drug-Drug Interactions

Background: Drug-related acute kidney disease is a common side effect of valacyclovir (VACV) treatment. Although analgesics are frequently administered concomitantly with VACV to treat the pain of herpes zoster, the differences between nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen in relation to VACV-related acute kidney injury (AKI) are unclear. The risk for AKI with concomitant use of VACV and renin–angiotensin system (RAS) inhibitors that can cause AKI via a similar mechanism to NSAIDs is also unknown. We therefore evaluated the association between concomitant use of these drugs and VACV-related AKI, which was characterized according to the Japanese Adverse Drug Event Report (JADER) database.

Methods: We analyzed data from the JADER database, which is a spontaneous reporting system. The reporting odds ratio was used to evaluate the signals of AKI.

Results: A high proportion of VACV-related AKI cases occurred in summer. There was an increase in AKI signal in cases with concomitant use of VACV and NSAIDs, while no increase was detected in cases with concomitant use of VACV and acetaminophen. AKI events in cases with concomitant use of VACV and NSAIDs were more frequent in older and female patients and those with hypertension. Additionally, a signal increase for VACV-related AKI was observed with concomitant use of RAS inhibitors, with or without NSAIDs.

Conclusions: We identified a seasonal variation in VACV-related AKI. Additionally, our findings indicate that acetaminophen might represent a safer analgesic than NSAIDs with respect to VACV-related AKI. We also identified candidate risk factors for AKI with concomitant use of NSAIDs, such as older age, female sex, and hypertension. Although further studies are warranted, our findings highlight the need to consider concomitant drug use and seasonal factors that lead to urinary output loss so that VACV-related AKI can be avoided.

Drug-encapsulated carbon (DECON): A novel platform for enhanced drug delivery

Current drug-delivery systems are designed primarily for parenteral applications and are either lipid or polymer drug conjugates. In our quest to inhibit herpes simplex virus infection via the compounds found in commonly used cosmetic products, we found that activated carbon particles inhibit infection and, in addition, substantially improve topical delivery and, hence, the efficacy of a common antiviral drug, acyclovir (ACV). Our in vitro studies demonstrate that highly porous carbon structures trapped virions, blocked infection and substantially improved efficacy when ACV was loaded onto them. Also, using murine models of corneal and genital herpes infections, we show that the topical use of drug-encapsulated carbon (DECON) reduced dosing frequency, shortened treatment duration, and exhibited higher therapeutic efficacy than currently approved topical or systemic antivirals alone. DECON is a nontoxic, cost-effective and nonimmunogenic alternative to current topical drug-delivery systems that is uniquely triggered for drug release by virus trapping.

Outcomes with acyclovir treatment in herpes simplex encephalitis after surgery for solid CNS tumors: a case report and systematic review of the literature

Background

Herpes simplex encephalitis (HSE) occurring within 30 days after neurosurgery for solid CNS tumors is underrecognized and underreported but remains important because of high morbidity and mortality. We present the case of a 41-year-old woman who had HSE after craniopharyngioma surgery, and delayed recognition and treatment led to a poor outcome. Subsequently, we review reported HSE cases after neurosurgery for solid CNS tumors and describe outcomes after treatment with and without acyclovir.

Methods

A literature search was performed for cases meeting the above criteria. Information was gathered regarding patient demographics, tumor types, symptoms, diagnostic workup, therapy, and outcomes.

Results

Eighteen cases were studied. Encephalopathy, fever, and seizures were the most common symptoms. A majority of patients (78%) received IV acyclovir, with a 79% survival rate with treatment. Mortality rate was 100% in untreated cases. The median time to starting acyclovir was 17 postoperative days (range, 8-53 days). Most patients received steroids, but its use was not associated with a specific outcome.

Conclusions

HSE may develop following neurosurgical resection, and the threshold for suspicion of this condition should be extremely low in a patient who shows compatible symptoms (encephalopathy, fever, or seizures) or does not recover as planned. Moreover, in case of suspicion of HSE, acyclovir should be promptly started until infection can be definitely ruled out. A delay in diagnosis of HSE and failure to treat may result in severe morbidity as well as mortality. This observation may warrant further study.

Pathological processes activated by herpes simplex virus-1 (HSV-1) infection in the cornea

Herpes simplex virus type-1 (HSV-1) is a ubiquitous pathogen that infects a large majority of the human population worldwide. It is also a leading cause of infection-related blindness in the developed world. HSV-1 infection of the cornea begins with viral entry into resident cells via a multistep process that involves interaction of viral glycoproteins and host cell surface receptors. Once inside, HSV-1 infection induces a chronic immune-inflammatory response resulting in corneal scarring, thinning and neovascularization. This leads to development of various ocular diseases such as herpes stromal keratitis, resulting in visual impairment and eventual blindness. HSV-1 can also invade the central nervous system and lead to encephalitis, a relatively common cause of sporadic fetal encephalitis worldwide. In this review, we discuss the pathological processes activated by corneal HSV-1 infection and existing antiviral therapies as well as novel therapeutic options currently under development.

SIADH with Severe Hyponatremia in an Elderly Man with Herpes Zoster Infection: A Causal or Casual Association?

Syndrome of inappropriate antidiuretic hormone (SIADH) secretion is the most common cause of hypotonic hyponatremia in hospitalized patients. An elderly man with severe symptomatic hyponatremia (109 mEq/L) was diagnosed with SIADH that was likely secondary to large cutaneous herpes zoster (HZ) infection. Hypertonic saline and tolvaptan improved the patient's sodium levels and clinical condition. A one month after discharge, tolvaptan was withdrawn, due to inadequate prescription criteria, after which hyponatremia relapsed several times and was properly treated; eventually fever and sopor occurred and the patient died. SIADH secondary to HZ may induce life-threatening and long-lasting hyponatremia, which requires a prompt diagnosis and treatment.

Oral acyclovir induced hypokalemia and acute tubular necrosis a case report

Background

Acyclovir is one of the most common prescribed antiviral drugs. Acyclovir nephrotoxicity occurs in approximately 12–48% of cases. It can present in clinical practice as acute kidney injury (AKI), crystal-induced nephropathy, acute tubulointerstitial nephritis, and rarely, as tubular dysfunction. Electrolytes abnormalities like hypokalemia, were previously described only when given intravenously.

Case presentation

A 54 year-old female presented with weakness and lower extremities paresis, nausea and vomiting after receiving oral acyclovir. Physical examination disclosed a decrease in the patellar osteotendinous reflexes (++ / ++++). Laboratory data showed a serum creatinine level of 2.1 mg/dL; serum potassium 2.1 mmol/L. Kidney biopsy was obtained; histological findings were consistent with acute tubular necrosis and acute tubulointerstitial nephritis. The patient was advised to stop the medications and to start with oral and intravenous potassium supplement, symptoms improved and continued until serum potassium levels were > 3.5 meq/L.

Conclusions

The case reported in this vignette is unique since it is the first one to describe hypokalemia associated to acute tubular necrosis induced by oral acyclovir.

The Prevention and Management of Contrast-induced Acute Kidney Injury: A Mini-review of the Literature

Contrast-induced acute kidney injury, also called contrast-induced nephropathy, is one of the main causes of acute renal failure/acute kidney injury (AKI) in hospitalized patients within 48 to 72 hours of contrast media administration during various radiologic procedures. Several factors can be responsible for contrast-induced acute tubular necrosis (ATN); however, patient and procedure-related factors play the lead role in determining the development of contrast-induced nephropathy. There is no definitive treatment and hydration remains the mainstay preventive strategy. This article will review the incidence, criteria for definitive diagnosis, and an effective approach on how to prevent contrast-induced nephropathy in a clinical setup.

Incidence and predictors of intravenous acyclovir-induced nephrotoxicity

To assess the incidence, predictive factors, and prognosis of acyclovir-induced nephrotoxicity. We conducted a historical prospective cohort study of patients treated with intravenous acyclovir in North Denmark Region from 2009 to 2016. Information on baseline demographics, co-morbidities, plasma creatinine, and treatment was obtained from the medical records. The primary outcome was an increase of ≥ 40 μmol/L in plasma creatinine level from baseline. We included 276 patients treated with intravenous acyclovir of which 29 (10.5%) met the primary outcome. In 14 cases, the treating physician considered acyclovir the main reason for nephrotoxicity, whereas a potential competing cause of renal impairment was present among the 15 remaining patients. Hypertension was the only predictive factor associated with nephrotoxicity (risk ratio (RR), 2.77; 95% confidence interval (CI), 1.41-5.46), while having no co-morbidities was protective (RR, 0.32; CI, 0.16-0.63). In all cases, the nephrotoxicity was reversible following rehydration and dose reduction or discontinuation of the drug. However, the normalized plasma creatinine upon treatment was significantly higher between cases with acyclovir-induced nephrotoxicity than cases with a potential competing cause (median [interquartile range (IQR)], 93.5 μmol/L [85-108] vs 75 μmol/L [66.5-88]; p = 0.019). Acyclovir-induced, reversible nephrotoxicity was observed in 5.1-10.5% of patients. It is difficult to predict who will develop acyclovir-induced nephrotoxicity; it may occur late in treatment and hypertension was the only independent predictive factor, while the absence of co-morbidities was protective. Ensuring hydration, frequent evaluations of renal function, and corresponding dose adjustment of intravenous acyclovir treatment seem prudent.

Heterogeneous polymer composite nanoparticles loaded in situ gel for controlled release intra-vaginal therapy of genital herpes

Herpes simplex virus causes serious and contagious genital infections in high percentage of female population world-wide. Acyclovir is a clinically successful antiviral molecule till date, in-spite of limitations as poor solubility, low half-life, reduced oral bioavailability and side effects at higher doses. In the present work, controlled release in situ gelling system loaded with polymeric nanoparticles of acyclovir containing a dose of drug equivalent to 105mg/day has been developed. The formulation containing drug loaded polyvinyl pyrrolidone-Eudragit RSPO hybrid polymeric nanoparticles (Size ∼99±3nm, Zeta ∼+26.1±1.5mV) in 15% Pluronic F-127 gel exhibited improved permeability through vaginal membrane (KP=2.20±0.19×10(-6)cm/s). The nanoparticles showed enhanced viability for vaginal epithelial cell lines up to concentration of 100-250μg/mL. The formulation was evaluated for bioavailability and biodistribution through intra-vaginal administration in rat models. The nanoparticle in situ gel formulation maintained an average therapeutic drug level of 0.6±0.2μg/mL in plasma for 24h. Significant improvement in mean residence time of the drug (12.52±1.12h) was observed with a two-fold increase in the relative bioavailability (AUC0-24h=14.92±2.44μgh/mL) compared to that of the pure drug (7.18±1.79μgh/mL). The tissue distribution was 2-3 folds higher in animals treated with nanoparticles in situ gel compared to that of pure drug. Sustained release of drug in vivo was demonstrated, ensuring the suitability of the formulation for clinical therapy in female population.

Dosing Practices of Intravenous Acyclovir for Herpes Encephalitis in Obesity: Results of a Pharmacist Survey

BACKGROUND

Dosing of intravenous acyclovir for herpes encephalitis in obese patients is recommended to be based on ideal body weight. However, limited data support this recommendation, and recent data suggest this may lead to underdosing.

OBJECTIVE

To determine national dosing practices of intravenous acyclovir across a range of patient weights.

METHODS

A survey was distributed to members of the American College of Clinical Pharmacy Critical Care and Infectious Diseases Practice & Research Networks listservs. Data collected included demographic information and dosing of acyclovir, given consistent patient cases with varying patient weight.

RESULTS

A total of 264 pharmacists participated in the survey, with 240 (90.9%) participants completing the survey. Participants were predominately clinical pharmacists. As patient weight increased, respondents were more apt to dose based on an adjusted body weight, with dosing in the obese and morbidly obese showing a clear lack of consistency.

CONCLUSIONS

Intravenous dosing of acyclovir for herpes encephalitis is variable, especially in obese patients, and does not reflect recommendations. Limited data provide conflicting recommendations for dosing in obese patients, and future studies are necessary to optimize patient outcomes and prevent toxicity.

Synthesis of hybrid polymer blend nanoparticles and incorporation into in situ gel foam spray for controlled release therapy using a versatile synthetic purine nucleoside analogue antiviral drug

Antiviral drug loaded nanoparticles is incorporated intoin situgel for controlled release therapy. Chemical and physical interactions of drug and polymers in the system influenced their characteristics and drug release mechanism.