Foscarnet therapy for congenital cytomegalovirus liver fibrosis following prenatal ascites

Management of neonatal central nervous system viral infections: Knowledge gaps and research priorities

Congenital CMV, enteroviruses, human parechovirus and herpes simplex virus are all common causes of severe central nervous system (CNS) infection in neonates. The introduction of screening (i.e. newborn hearing screening programme), integration of molecular syndromic testing (i.e. multiplex polymerase chain reaction assays) and increase in sexually transmitted infections (i.e. anogenital herpes) have contributed to increases in each of these infections over the last decade. However, therapeutic options are highly limited in part due to the lack of epidemiological data informing trials. This review will describe our current understanding of the clinical burden and epidemiology of these severe neonatal CNS infections, outline the novel antiviral and vaccines in the pipeline and suggest future research studies which could help develop new therapeutics.

Nongenetic risk factors for infantile cataracts: Systematic review of observational studies

INTRODUCTION

While infantile cataracts are a major cause of childhood blindness, risk factors remain unknown for approximately two-thirds of cases.

METHODS

We systematically searched electronic databases PubMed, Ovid MEDLINE, Web of Science, and Scopus, from inception through March 2018, to identify relevant cohort, case-control, cross-sectional studies, case reports, and case series. We also manually screened bibliographies and consulted with experts in the field to identify additional publications. We reviewed cross-sectional studies, case reports, and case series and provided a narrative summary of the reported potential risk factors. We evaluated methodological qualities of cohort and case-control studies, extracted relevant data, and described statistically significant associations with infant, maternal, and paternal characteristics. Quality assessment and data extraction were conducted by two reviewers independently. All discrepancies were discussed with the senior author and resolved by consensus.

RESULTS

Overall, 110 publications were included in the review, 33 of which were cohort and case-control studies. Most of these studies (n = 32) used population-based data and had either excellent (n = 31) or good (n = 2) methodological quality. Nine studies reported statistically significant associations with infant characteristics (preterm birth, low birth weight), maternal occupations and diseases during pregnancy (untreated hypertension, infections), and paternal sociodemographics (younger age, employment in sawmill industry during pregnancy).

CONCLUSIONS

This systematic literature review provided a comprehensive summary of the known nongenetic risk factors for infantile cataracts, identified gaps in the literature, and provided directions for future research. Studies identifying modifiable risk factors are warranted to design interventions aimed at primary prevention of infantile cataracts.

Anti-viral therapy for congenital cytomegalovirus infection: pharmacokinetics, efficacy and side effects

Congenital cytomegalovirus (CMV) infection is the most common congenital infection in the world with approximately 0.5-2% of all live born infants, and can cause early or late severe neurological and neurisensorial damage. Although no drug has been licensed for therapy of congenital CMV infection, ganciclovir (GCV) and its oral pro-drug, valganciclovir (val-GCV), is increasingly being administrated to symptomatic infants, to improve neurodevelopmental and auditory outcome. Other potentially efficacious for therapy of congenital CMV disease are foscarnet and cidofovir, which have only been administered in few cases. A literature search was performed to look for evidence based or scientific articles evaluating pharmacokinetics, efficacy, and side effects of GCV/val-GCVand the other two anti-viral drugs.

Safety of alternative antiviral agents for neonatal herpes simplex virus encephalitis and disseminated infection

OBJECTIVE

To review the evidence describing the safety of ganciclovir and foscarnet in neonates in order to guide treatment for central nervous system or disseminated herpes simplex infections in cases of acyclovir shortage or resistance.

METHODS

PubMed, Ovid Medline, and International Pharmaceutical Abstracts were searched using the thesaurus and text-word terms "ganciclovir" and "foscarnet," with birth to 1 month age limits. Thirty-two eligible publications describing safety in neonates were identified.

RESULTS

In 340 neonates treated for cytomegalovirus (CMV), life-threatening neutropenia (absolute neutrophil count <0.5 × 10(9)/L) was reported in 8.8% of patients following up to 12 months of ganciclovir administered intravenously. Neutropenia and thrombocytopenia occurred in 25.6% and 6.2% of neonates, respectively. Changes in serum creatinine concentration of >0.2 mg/dL occurred in <1% of neonates. Hepatic transaminase increases or unspecified changes in liver function tests were reported in 6.2% of neonates with hyperbilirubinemia being observed in 3.5% of total neonates. Three out of four neonates receiving foscarnet for acyclovir-resistant herpes infection or CMV survived with minimal sequelae. Neither nephrotoxicity nor electrolyte or mineral imbalances were reported.

CONCLUSIONS

Similar to what is seen in adolescents and adults, ganciclovir use in neonates is commonly associated with neutropenia, and the frequency of occurrence is comparable. The link between hepatotoxicity and ganciclovir should be interpreted with caution because of overlapping clinical manifestations of CMV. Only case reports are available describing foscarnet use in neonates, but adverse drug reactions were not observed. More research on these two agents is needed to draw conclusions about adverse drug reaction rates in the neonatal population.

Treatment of congenital cytomegalovirus: where are we now?

Congenital cytomegalovirus (CMV) is the most common congenital infection in the USA, affecting approximately 1% of all live births. While the majority of infants will remain asymptomatic, approximately 10% will be symptomatic at birth and another 10-15% will go on to develop problems during the first 6 years of life. Congenital CMV is now the most common cause of nonhereditary sensorineural hearing loss in children. Accordingly, researchers and clinicians have long been interested in identifying strategies to prevent or treat symptomatic congenital CMV infection. This article reviews congenital CMV with a focus on treatment strategies.

Antivirals for cytomegalovirus infection in neonates and infants: focus on pharmacokinetics, formulations, dosing, and adverse events

Cytomegalovirus (CMV) infection is very common throughout the world, and has become more of a pediatric clinical concern given the high incidence of congenital CMV infections as well as the increasing numbers of immunocompromised patients. Because of this, the need for antiviral therapies in infants and neonates is growing. Currently, there are four antivirals available that are active against CMV: ganciclovir, valganciclovir, foscarnet, and cidofovir. At this time, none have approved indications for use in children. Although there are limited data regarding the dose, pharmacokinetics (PK), safety, and adverse events for some of these antivirals, ganciclovir, and its oral prodrug valganciclovir, have been the best studied in the infant and neonate populations. In general, pharmaceutical PK studies in young children are limited by the constraints of sampling difficulties and blood volume requirements; fewer sampling times and studies may be available for drug evaluation. Given this caveat, ganciclovir and valganciclovir PK in children thus far appears to follow a monocompartmental model, contrary to what has been described in adults. However, when normalized for weight, the volume of distribution, clearance, and half-life of ganciclovir are similar to those found in adults. Given the findings that ganciclovir (and thus valganciclovir) clearance is directly proportionate to renal function, care must be taken when administering the drug to patients with impaired renal function. Recent studies evaluating valganciclovir PK in infants (at a dose of 16 mg/kg every 12 hours) have shown similar areas under the plasma concentration-time curve (AUCs) to intravenous ganciclovir (at a dose of 6 mg/kg every 12 hours), and that these AUCs remain quite stable over a number of weeks. As seen in adults, oral ganciclovir has a low bioavailability (4.8% in a pediatric analysis) and is therefore a poor alternative for treating serious CMV infections. Neutropenia is the most frequent toxicity associated with ganciclovir and valganciclovir therapy, whereas significant (and possibly irreversible) renal toxicity can be seen with cidofovir. Foscarnet administration can also result in renal toxicity as well as significant electrolyte imbalances. Several of these drugs have potential toxicities that are of concern, including carcinogenesis, teratogenesis, and azospermia (ganciclovir, valganciclovir, and cidofovir) and deposition into bone or dentition (foscarnet) that may have significant implications when treating an infant. Given these potential ill effects, careful consideration of the indications for the clinical use of these antivirals is necessary before using them for CMV infection in neonates and infants.

Fetal ascites owing to congenital cytomegalovirus: response to ganciclovir

A term newborn with severe congenital cytomegalovirus (CMV) infection is described. Fetal ascites was detected at 28 weeks gestation, and at birth there was tense ascites. There was intra-uterine growth retardation, microcephaly, chorioretinitis, jaundice, purpura and pneumonitis. Computed tomographic scan of the brain showed ventriculomegaly with periventricular calcifications. Serology was positive for cytomegalovirus-specific immunoglobulin M, and cytomegalovirus DNA was detected in the ascitic fluid and urine by nested polymerase chain reaction. He received 6 weeks of treatment with ganciclovir. Ascites resolved spontaneously and liver function tests became normal. Although there was a good clinical response to ganciclovir therapy without any side-effects, on follow-up the infant had global developmental delay and bilateral sensorineural deafness.

A practical guide to the management of anophthalmia and microphthalmia

Congenital anophthalmia and microphthalmia are rare developmental defects of the globe. They often arise in conjunction with other ocular defects such as coloboma and orbital cyst. They may also be part of more generalised syndromes, such as CHARGE syndrome. Anophthalmia, microphthalmia, and coloboma are likely to be caused by disturbances of the morphogenetic pathway that controls eye development, either as a result of primary genetic defect, or external gestational factors, including infection or drugs that can influence the smooth processes of morphogenesis. The ophthalmologist is often the primary carer for children with anophthalmia and microphthalmia, and as such can coordinate the multidisciplinary input needed to offer optimal care for these individuals, including vision and family support services. They are able to assess the vision and maximise the visual potential of the child and they can also ensure that the cosmetic and social impact of anophthalmia or microphthalmia is minimised by starting socket expansion or referring to a specialist oculoplastics and prosthetics unit. A coordinated approach with paediatrics is necessary to manage any associated conditions. Genetic diagnosis and investigations can greatly assist in providing a diagnosis and informed genetic counselling.

Recent advances in the prevention and treatment of congenital cytomegalovirus infections

Continued but slow progress has led to recent advances in our understanding that congenital cytomegalovirus (CMV) infection has occurred. We understand that the most severe congenital disease occurs following a primary maternal infection during pregnancy. We now have the ability to accurately diagnosis a primary maternal infection using serologic studies of single serum sample. For pregnant women with young children, we know that child-to-mother CMV transmission can probably be prevented by hygienic intervention, and that for pregnant women who have acquired a primary CMV infection, mother-to-fetal transmission is probably preventable using CMV hyperimmune globulin. Although additional studies are needed, treatment of congenitally infected fetuses or newborns should be possible using either CMV hyperimmune globulin or antiviral agents such as ganciclovir or its derivates. Finally, recent evidence indicates that CMV replicates in the placenta, impairs development, and causes inflammation and dysfunction. This plus the reversibility of many manifestations of congenital infection in the fetus and newborn indicate that congenital CMV disease is in part a syndrome of placental insufficiency.

Epidemiology, pathogenesis and prevention of congenital cytomegalovirus infection

Cytomegalovirus is the most common cause of congenital infection. Congenital cytomegalovirus infection can follow both primary and recurrent maternal infections. It is associated with a significant burden of disease and death. The determinants of mother-to-child transmission and the pathogenesis of symptomatic fetal infection remain poorly understood. For a long time, congenital cytomegalovirus infection has been a neglected disease. Recently, the Institute of Medicine has recognized that the development of a vaccine against congenital cytomegalovirus infection is a public health priority, which should stimulate research in this area. The development of antiviral therapies to prevent symptoms in infected newborns also represents an important area of research.