Challenges for molecular and serological ZIKV infection confirmation.

BACKGROUND: Zika Virus (ZIKV), member of Flaviviridae family and Flavivirus genus, has recently emerged as international public health emergency after its association with neonatal microcephaly cases. Clinical diagnosis hindrance involves symptom similarities produced by other arbovirus infections, therefore laboratory confirmation is of paramount importance. DISCUSSION: The most reliable test available is based on ZIKV RNA detection from body fluid samples. However, short viremia window periods and asymptomatic infections diminish the success rate for RT-PCR positivity. Beyond molecular detection, all serology tests in areas where other Flavivirus circulates proved to be a difficult task due to the broad range of cross-reactivity, especially with dengue pre-exposed individuals. CONCLUSION: Altogether, lack of serological diagnostic tools brings limitations to any retrospective evaluation. Those studies are central in the context of congenital infection that could occur asymptomatically and mask prevalence and risk rates.

Persistence of Zika Virus After Birth: Clinical, Virological, Neuroimaging, and Neuropathological Documentation in a 5-Month Infant With Congenital Zika Syndrome.

During the Zika epidemic in Brazil, a baby was born at term with microcephaly and arthrogryposis. The mother had Zika symptoms at 10 weeks of gestation. At 17 weeks, ultrasound showed cerebral malformation and ventriculomegaly. At 24 weeks, the amniotic fluid contained ZIKV RNA and at birth, placenta and maternal blood were also positive using RT-qPCR. At birth the baby urine contained ZIKV RNA, whereas CSF at birth and urine at 17 days did not. Seizures started at 6 days. EEG was abnormal and CT scan showed cerebral atrophy, calcifications, lissencephaly, ventriculomegaly, and cerebellar hypoplasia. Bacterial sepsis at 2 months was treated. A sudden increase in head circumference occurred at 4 months necessitating ventricle-peritoneal shunt placement. At 5 months, the infant died with sepsis due to bacterial meningitis. Neuropathological findings were as severe as some of those found in neonates who died soon after birth, including hydrocephalus, destructive lesions/calcification, gliosis, abnormal neuronal migration, dysmaturation of nerve cells, hypomyelination, loss of descending axons, and spinal motor neurons. ZIKV RNA was detected only in frozen brain tissue using RT-qPCR, but infected cells were not detected by in situ hybridization. Progressive gliosis and microgliosis in the midbrain may have contributed to aqueduct compression and subsequent hydrocephalus. The etiology of progressive disease after in utero infection is not clear and requires investigation.

Descrição da sorologia IgM para Zika Vírus em pacientes com exposição vertical / Description of Zika Virus IgM serology in patients with vertical exposure

Objetivos: descrever os resultados da dosagem de IgM em pacientes com confirmação diagnóstica de infecção congênita pelo zika vírus, avaliando a relação com período no qual a infecção materna ocorreu, a janela diagnóstica e as alterações clínicas nos casos estudados. Metodologia: foram avaliados, de acordo com o momento de coleta e com a presença de alterações clínicas, os resultados das sorologias IgM realizadas pelo método MAC-ELISA licenciado pelo CDC, em 52 pacientes infectados pelo Zika vírus, acompanhados no Instituto Nacional de Saúde da Mulher da Criança e do Adolescente. Todos os casos estudados tiveram infecção congênita confirmada por RT-qPCR ao nascimento. Os resultados foram avaliados de acordo com a presença de alterações clínicas, utilizando o programa estatístico SPSS. Resultados: dos 52 pacientes avaliados 29 (55,8%) apresentaram IgM positiva e 23 (44,2%) negativa. Amostras colhidas nos primeiros 29 dias de vida apresentaram maior positividade em relação aos demais grupos, sendo 15 (71,4%) amostras positivas no grupo IgM<30 dias, 6 (42,9%) no grupo IgM 30-120 dias e 8 (47,1%) no grupo IgM >120 dias. Verificamos que as crianças infectadas no primeiro trimestre gestacional foram as que mais apresentaram IgM positivo na primeira coleta, correspondendo a 75,9% dos resultados positivos, seguidos de 10,3% no segundo trimestre e 13,8% no terceiro trimestre gestacional (p= 0,002). Observamos correlação entre a presença de alterações neurológicas e manifestações clínicas de síndrome zika congênita com resultados positivos de sorologia IgM no grupo que teve a amostra colhida nos primeiros 29 dias de vida. Conclusões: Mesmo sendo encontrada correlação com questões clínicas, o teste de IgM se demonstrou de baixa sensibilidade para o diagnóstico de infecção congênita pelo Zika vírus. Os melhores resultados de sensibilidade foram encontrados em pacientes que foram analisados nos primeiros 29 dias de vida e quando a infecção materna ocorreu no primeiro trimestre gestacional. Observamos mais resultados positivos em pacientes com SZC do que nos pacientes NSZC. O ensaio sorológico, embora não possa ser usado como método de exclusão diagnóstica, deve ser realizado diante dos casos suspeitos, principalmente em pacientes sintomáticos, na menor janela de tempo possível para aumentar a chance do diagnóstico de infecção congênita pelo vírus Zika. Mais estudos, com amostras pareadas, são necessários para comprovação de reinfecção, reativação e de persistência de IgM prolongada.

Research goals: to describe the results of the serological tests of patients diagnosed with congenital infection by Zika virus (ZIKV), evaluating the period in which the maternal infection occurred, the time at which the sample was collected and eventual clinical changes. Methodology: The results of the Zika MAC-ELISA test (licensed by the Centers for Disease Control and Prevention ­ CDC) of 52 childrens followed at the Fernandes Figueira Institute were used in this study. All patients had congenital infection confirmed by positive RT-qPCR at birth. The data were linked to the the clinical data, the time of maternal infection, the diagnostic window and the child's age at the time of sample collection. Results: Out of 52 patients carrying the Zika virus, 29 (55.8%) presented positive IgM and 23 (43.3%) negative, showing little sensitivity of the method for the diagnosis of congenital infection by Zika virus. The positive result ratio was also subject to the patient's life time. Samples collected in patient's first 29 days of life showed greater ratio of positive results than the samples of the other groups; 15 (71.4%) positive samples in the IgM group <30 days, 6 (42.9%) in the IgM group 31-120 days and 8 (47.1%) in the IgM group> 120 days. It was verified that the infected children in the first trimester were the ones that presented the most positive IgM in the first collection, corresponding to 75.9% of the positive results, followed by 10.3% in the second trimester and 13.8% in the third trimester (p = 0.002). We found correlation between serological IgM positive results and the presence of neurologic findings and CZS. Conclusions: we obtained better results in patients whose samples samples had ben collected during the first 30 days of life, especially when maternal infection occurred in the first trimester of pregnancy. We found more positive results in patients with SZC than in NSZC patients. The serological test, although it can not be used as a method of diagnostic exclusion, should be performed in the presence of suspected cases, especially in symptomatic patients. More studies, with paired samples, are needed in order to prove reinfection, reactivation, and prolonged IgM persistence.

Miíase associada a erisipela bolhosa / Case report: myiasis associated to bullous erysipelas

Miíase é a presença de larvas de moscas em tecidos do homem ou de outros animais vertebrados, onde se nutrem e evoluem como parasitos. Erisipela é uma celulite superficial que apresenta comprometimento do plexo linfático subjacente, cujo principal agente etiológico é Streptococcus (Rosenbach,1884) beta hemolítico do grupo A de Lancefield. Caracteriza-se por placas eritematosas acompanhadas de dor e edema. Este é o relato de um caso raro de paciente idosa internada em hospital público para tratamento de erisipela bolhosa no membro inferior esquerdo, em cujas lesões, durante a internação, foi detectada a presença de miíase. Foram retiradas várias larvas vivas com auxílio de pinça e prescrita ivermectina para erradicar possíveis larvas remanescentes. O diagnóstico precoce e o tratamento correto das lesões primárias são fundamentais para evitar a ocorrência de afecções como a miíase, cuja instalação atrasa o tratamento e pode agravar o prognóstico.

Myiasis is the presence of fly larvae in tissues of humans or other vertebrates,where they feed and develop as parasites. Erysipelas is a superficial cellulitis with involvement of underlying lymphatic plexus, characterized by erythematous plaques accompanied by pain and swelling. We report a case of an aged patient admitted to a public hospital for treatment of bullous erysipelas in the left lower limb, who developed cutaneous myiasis during hospitalization. Several larvae wereremoved with the aid of forceps and ivermectin was prescribed to eradicate possible remaining larvae. Early diagnosis and correct treatment of the lesions are essential to prevent the occurrence of diseases such as myiasis.