Download Onyinyechi Ogbumbadiugha Microbiology Journal Club Review

Onyinyechi Ogbumbadiugha
Microbiology Journal Club Review
April 6th 2016
Article Title: Ocular Findings in Infants with Microcephaly Associated with Presumed Zika Virus
Congenital Infection in Salvador, Brazil
Overview
 Case series, observational study
 Major Findings: “Congenital infection due to presumed ZIKV exposure is associated with visonthreatening findings, which include bilateral macular and perimacular lesions as well as optic
nerve abnormalities in most cases.”
Background/Introduction
 There is a great deal of background provided concerning the Zika virus as well as related
arboviruses. However, there was no information provided about ocular lesions although this is the
focus of the paper. This should certainly be added to this section.
 How accurate is the Zika-related microcephaly clinical diagnosis if it was previously stated in the
introduction that the only method of diagnosing Zika is via real time PCR which is not helpful for
confirming Zika in infants. How is it certain that the infants actually have Zika and not a Zika
related illness?
 It was stated that the recent increase in microcephaly in newborns is suspected of being strongly
associated with Zika congenital infection and you cite the discovery of the Zika virus in the
amniotic fluid of two pregnant women who gave birth to babies with reduced head sizes. This is
only two women out of 3174 new microcephalic cases which does not seem to point to a strong
correlation between Zika infection and microcephaly. More/stronger evidence of a correlation
should be provided. In addition, were the head sizes of these two children simply smaller than
average or actually microcephaly? I think this should be specified.
Methods
 It was stated that the Brazilian Ministry of Health revised the definition for microcephaly from
33cm to 32 cm or less. Why was this done? I think this should be stated in your paper.
 “A detailed clinical history was obtained, including the prenatal and postnatal history and
maternal systemic history”. Was this how it was determined that all of the mothers were infected
with Zika? How you determined that the mothers of the infants had been infected with Zika
should be explicitly stated.
 It was not stated how you chose the infections included in the serologic examinations. Why are
the infections listed chosen? Why were other viruses with similar symptomology such as Dengue
not included?
 All of the mothers underwent eye examinations as well as the infants. Why exactly was this
done?
Results
 Some of the symptoms of Zika such as arthralgia can be associated with pregnancy. It does not
appear that it can be distinguished whether these symptoms are due to Zika or simply due to
normal pregnancy.
Discussion
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It is stated that the rate of ocular abnormalities in Zika patients is very high in the age group
looked in this study in comparison to the rates of ocular abnormalities associated with other
congenital infections. You should provide the average rate of ocular abnormalities for other
congenital infections.
You pose the question whether patients without microcephaly should be screened for ocular
lesions. When you say “patients without microcephaly”, do you mean all infants, just infants
whose mothers’ exhibited signs of Zika infection during pregnancy or just infants whose mothers
tested positive for the Zika virus?
You state that unlike Duffy et al. 2009, that conjunctivitis may not be an important clinical
finding in the diagnosis of Zika. In your study, you asked the mother’s whether they experienced
any signs or symptoms of conjunctivitis; this was not determined clinically or through physical
examination. Did the Duffy study also rely on self-reporting? If not, this could lead to a disparity
in results.
Conclusion
 It is stated that, “the findings can contribute to the diagnosis of ZIKV congenital infection in
children with congenital microcephaly”. Has it been established that these eye abnormalities
(besides the retinal lesions) are exclusive to Zika? If so, then this should be stated.
Final recommendation: Provisional acceptance with minor revisions