Table 1. Clinical characteristics of suspected microcephaly cases, Salvador, Brazil, April 2015–July 2016 (n = 365).
| Clinical characteristics | Congenital brain abnormalities diagnosis | |||
|---|---|---|---|---|
| Confirmed (n = 166) | Excluded (n = 199) | |||
| n | % | n | % | |
| Male sex | 76 | 45.8 | 65 | 32.7 |
| Gestational age at birtha | ||||
| < 37 weeks | 54 | 33.3 | 13 | 7.0 |
| 37–42 weeks | 108 | 66.7 | 172 | 93.0 |
| Head circumference | ||||
| Head circumference (cm), median and IQRb,c | 30.0 | 28.0–31.0 | 32.0 | 31.0–32.0 |
| Head circumference (cm), min–maxb,c | 21.5–42.0 | 28.0–36.0 | ||
| Intracranial imaging performed | ||||
| Ultrasound | 136 | 81.9 | 192 | 96.5 |
| Computed tomography | 53 | 31.9 | 9 | 4.5 |
| Magnetic resonance imaging | 17 | 10.2 | 4 | 2.0 |
| Image findings consistent with congenital malformations | ||||
| Intracranial calcifications | 143 | 86.1 | 0 | 0.0 |
| Ventriculomegaly | 111 | 66.9 | 0 | 0.0 |
| Agenesis of the corpus callosum | 20 | 12.1 | 0 | 0.0 |
| Dysgenesis of the corpus callosum | 19 | 11.5 | 0 | 0.0 |
| Lissencephaly | 17 | 10.2 | 0 | 0.0 |
| Cerebellar abnormalitiesd | 9 | 5.4 | 0 | 0.0 |
| Anencephaly | 3 | 1.8 | 0 | 0.0 |
| Other findings | ||||
| Oligohydramnios | 17 | 10.2 | 7 | 3.5 |
| Intrauterine growth restriction | 14 | 8.4 | 2 | 1.0 |
| Subependymal cysts | 16 | 9.6 | 7 | 3.5 |
| Arthrogryposis | 11 | 6.6 | 0 | 0.0 |
| Auditory abnormalitiese | 20 | 19.2 | 10 | 11.5 |
| Ophthalmological abnormalitiesf | 13 | 18.8 | 3 | 4.5 |
| Deathg | 6 | 3.6 | 0 | 0.0 |
IQR: interquartile range.
Suspected microcephaly cases may have undergone more than one imaging testing and presented with more than one finding.
a Data available for 162 confirmed cases and 185 excluded cases. The lowest gestational age for the confirmed and excluded cases were 20 and 30 weeks, respectively.
b Data on head circumference were not available for two confirmed cases. Data on head circumference of three confirmed cases and eight excluded cases were not considered in the analysis due to a late measurement without a precise date (> 28 days post birth).
c Some of the cases from both groups of confirmed and excluded congenital brain abnormalities diagnosis had a head circumference size greater than the screening limits used to detect microcephaly. This is because reporting cases of spontaneous abortions, stillbirths or pregnancies with any detected alterations in the fetal central nervous system in women with self-reported history of rash during pregnancy was also encouraged, though not mandatory.
d Cerebellar vermis agenesis or cerebellar hypoplasia.
e Data on auditory abnormalities were available for 104 confirmed cases (86 by auditory screening method, three by brainstem evoked response audiometry test (BERA) and 15 by both) and for 87 excluded cases (79 by auditory screening method, three by BERA test and five by both).
f Data on ophthalmological abnormalities were available for 69 confirmed cases and for 67 excluded cases. Among the confirmed cases, two had pigmentary abnormalities in macula, one abnormal red reflex, one bilateral chorioretinal atrophy and optic disc hypoplasia, one cataracts, one macular atrophy, one corneal excoriation, one chorioretinitis, one optic disc excavation, one coloboma, and three without information on type of abnormality. Among excluded cases, one had retinal haemorrhage, one retinal excavation and one cataracts.
g Death occurred on the day of birth for two cases, within 2 days for one case, within 2 months for two cases and within 4 months for one case.