SummaryStarting with the outbreak in Brazil, Zika virus (ZIKV) infection has been correlated with severe syndromes such as congenital Zika syndrome and Guillain-Barré syndrome. Here, we review the status of Zika virus pathogenesis in the central nervous system (CNS). One of the main concerns about ZIKV exposure during pregnancy is abnormal brain development, which results in microcephaly in newborns. Recent advances in in vitro research show that ZIKV can infect and obliterate cells from the CNS, such as progenitors, neurons, and glial cells. Neural progenitor cells seem to be the main target of the virus, with infection leading to less cell migration, neurogenesis impairment, cell death and, consequently, microcephaly in newborns. The downsizing of the brain can be directly associated with defective development of the cortical layer. In addition, in vivo investigations in mice reveal that ZIKV can cross the placenta and migrate to fetuses, but with a significant neurotropism, which results in brain damage for the pups. Another finding shows that hydrocephaly is an additional consequence of ZIKV infection, being detected during embryonic and fetal development in mouse, as well as after birth in humans. In spite of the advances in ZIKV research in the last year, the mechanisms underlying ZIKV infection in the CNS require further investigation particularly as there are currently no treatments or vaccines against ZIKV infection.

Objective To compare initial brain computed tomography (CT) scans with follow-up CT scans at one year in children with congenital Zika syndrome, focusing on cerebral calcifications. Design Case series study. Setting Barão de Lucena Hospital, Pernambuco state, Brazil. Participants 37 children with probable or confirmed congenital Zika syndrome during the microcephaly outbreak in 2015 who underwent brain CT shortly after birth and at one year follow-up. Main outcome measure Differences in cerebral calcification patterns between initial and follow-up scans. Results 37 children were evaluated. All presented cerebral calcifications on the initial scan, predominantly at cortical-white matter junction. At follow-up the calcifications had diminished in number, size, or density, or a combination in 34 of the children (92%, 95% confidence interval 79% to 97%), were no longer visible in one child, and remained unchanged in two children. No child showed an increase in calcifications. The calcifications at the cortical-white matter junction which were no longer visible at follow-up occurred predominately in the parietal and occipital lobes. These imaging changes were not associated with any clear clinical improvements. Conclusion The detection of cerebral calcifications should not be considered a major criterion for late diagnosis of congenital Zika syndrome, nor should the absence of calcifications be used to exclude the diagnosis.

The ability of diethylcarbamazine (DEC) to kill adult Wuchereria bancrofti worms was evaluated by examining lymphatic nodules formed after treatment with 4 different treatment schedules of 193 males living in the endemic area of Greater Recife, Brazil. Lymphatic nodules appeared in the spermatic cord or upper extremities in 43 of 138 microfilaraemic individuals, in 3 of 30 amicrofilaraemic patients with filarial disease manifestations, and in 1 of 25 asymptomatic amicrofilaraemic residents of the endemic area treated with DEC. Fourteen of these nodules were surgically removed 10-150 d after the start of treatment. Regardless of the DEC dosage and schedule used, all nodules contained damaged and degenerating adult worms. An exuberant granulomatous process with large numbers of eosinophils and progressive fibrosis gradually developed around the dead parasites. The mechanism(s) by which DEC killed adult W. bancrofti could not be determined.

No abstract

Severe microcephaly and CNS abnormalities may be associated with congenital ZIKV syndrome.

IMPORTANCE Hydrocephalus is a treatable but potentially fatal complication that has not been previously described in congenital Zika syndrome (CZS).OBJECTIVE To describe the clinical features and imaging findings in 24 patients with congenital Zika syndrome (CZS) who developed hydrocephalus. DESIGN, SETTING, AND PARTICIPANTSThis case series included patients with hydrocephalus who were born in October and November 2015 and followed up until mid-2017 in the 2 largest national referral centers for CZS in Brazil. The participants included consecutively enrolled children with a clinical and laboratorial diagnosis of CZS who developed clinical and/or image findings suggestive of hydrocephalus and who were confirmed to experience increased intracranial hypertension during ventriculoperitoneal shunt procedures. MAIN OUTCOMES AND MEASURESTo retrospectively describe clinical and image findings in these 24 patients. RESULTS This multicenter cohort included 308 patients with CZS; 24 consecutive children were enrolled in this study. These children were aged between 3 to 18 months, and 13 of 24 (54%) were female. All patients presented with at least 1 positive test result for anti-Zika antibodies in cerebrospinal fluid or serum and had classic signs of CZS. At the time of hydrocephalus diagnosis, only 14 of 24 patients (58%) had symptoms and signs suggestive of hydrocephalus (mainly worsening seizures, vomiting, irritability, and/or sudden increase of head circumference percentile). Two of 24 patients (8%) had no symptoms suggestive of hydrocephalus but were found to have reduced brain volume on repeated imaging. Cerebellar or brainstem hypoplasia on baseline imaging were found in 18 of 23 patients (78%). At the second computed tomographic scan, all patients showed a marked increase of ventricular volume, compatible with communicating hydrocephalus, and reduction of brain tissue that was visibly worse than on baseline imaging for the 23 patients with repeated scans. CONCLUSIONS AND RELEVANCEWe present evidence that hydrocephalus is a complication of CZS in at least a proportion of patients. The clinical spectrum of this condition continues to evolve, but given that presenting signs and symptoms of hydrocephalus can be challenging to recognize in CZS, we provisionally recommend that high suspicion and appropriate monitoring for hydrocephalus should be part of the standard care of patients with CZS.

No abstract

No abstract