Movement disorders in children with congenital Zika virus syndrome

Abstract

Background: Congenital Zika Virus Syndrome (CZVS) denotes the neurologic and developmental sequelae of congenital infection of the Zika virus. While prior studies have detailed the associated clinical phenotypes, new findings continue to be identified. Abnormal postures and movements have been previously described in children with CZVS, but not in detail.

Objective: To examine a cohort of infants with CZVS and characterize the spectrum of motor abnormalities, especially movement disorders.

Design: Cross-sectional prospective study of 21 infants with confirmed CZVS.

Setting: Single-center cohort of 32 patients with serologically confirmed CZVS cared for in a referral center in Brazil.

Participants: 21 children (67% female), evaluated by two child neurologists and one movement disorders specialist, with clinical and laboratory diagnosis of CZVS aged between 16 and 30 months, with a mean age of 16 months at the time of the last examination.

Main outcome(s) and measure(s): Prospective neurologic examination by a team of three neurologists, including one movement disorders specialist. Sixteen (76.2%) children had a longitudinal evaluation with a six-month interval. The same team of experts analyzed recorded videos of all patients to characterize motor abnormalities and movement disorders. Neuroimaging findings were also analyzed to correlate with clinical findings.

Results: Twenty (95.2%) patients presented with dystonic postures, including "125" posture of the fingers in 17 (80.1%), "swan neck" posture of the fingers in three (18.8%), oromandibular dystonia in nine (42.9%), extensor axial hypertonia in eight (38.1%) and internal rotation of the shoulder posture in two (9.5%). Four (19%) patients had tremor. All children had malformations of cortical development, and in 13 (61.9%), the pattern was consistent with a severe and diffuse gyral simplification. Seventeen children (81%) had calcification in the transition of grey and white matter, whereas 11 (52.4%) patients had basal ganglia calcifications.

Conclusion and relevance: In our series, dystonic postures and other extrapyramidal signs were frequent and potentially disabling. Although children with CZVS are assessed and treated for spasticity, dystonia and other movement disorders remain neglected. This study emphasizes that extrapyramidal findings may potentially influence optimal strategies for rehabilitation and management.

Keywords: Dystonia; Hypertonia; Movement disorder; Zika virus.