RESUMO
Purpose: To describe the clinical features of congenital cataract (CC) in a Tunisian cohort and to assess the surgical outcomes of primary intraocular lens implantation in two groups based on the age at surgery. Methods: This study was a prospective analysis of children under 5 years with CC that were operated between January 2015 and 2020. The surgery consisted of phacoaspiration with posterior capsulorhexis and primary implantation. Group 1 comprised children operated at <2 years of age and Group 2 comprised children operated between 2 and 5 years. Peri and postoperative surgical events as well as refractive and visual outcomes were compared between both the groups. Results: Fifty-five (84 eyes) infants were enrolled. Group 1 included 30 (48 eyes) children and Group 2 included 25 (36 eyes) patients. The mean follow-up was 27.60 ± 19.89 months. The mean delay between the diagnosis and the cataract surgery was 11.97 ± 13.84 months. Of 14 (16.7%) eyes with postoperative visual axis opacification (VAO), 9 (10.7%) eyes required pars plana membranectomy. The VAO was not statistically associated with the age at surgery (P = 0.112), but significantly correlated with sulcus implantation (P = 0.037). The final mean visual acuity was 0.51 logMAR and comparable between both the groups (P = 0.871). Poor visual outcome was significantly associated with low age at presentation (<6 months; P = 0.039), delay between the diagnosis and time of surgery (P = 0.001), preoperative nystagmus (P = 0.02), and poor parental compliance to amblyopia treatment (P = 0.009). Conclusions: Primary implantation seems to be safe and efficient. VAO appears to become an avoidable occurrence owing to better surgical techniques. Amblyopia remains the biggest barrier to final visual outcome.
RESUMO
Intellectual disability (ID) often co-occurs with other neurologic phenotypes making molecular diagnosis more challenging particularly in consanguineous populations with the co-segregation of more than one ID-related gene in some cases. In this study, we investigated the phenotype of three patients from a large Tunisian family with significant ID phenotypic variability and microcephaly and performed a clinical exome sequencing in two cases. We identified, within the first branch, a homozygous variant in the TRAPPC9 gene (p.Arg472Ter) in two cases presenting severe ID, absent speech, congenital/secondary microcephaly in addition to autistic features, supporting the implication of TRAPPC9 in the "secondary" autism spectrum disorders and congenital microcephaly. In the second branch, we identified a homozygous variant (p.Lys189ArgfsTer15) in the CDK5RAP2 gene associated with an heterozygous TRAPPC9 variant (p.Arg472Ter) in one case harbouring primary hereditary microcephaly (MCPH) associated with an inter-hypothalamic adhesion, mixed hearing loss, selective thinning in the retinal nerve fiber layer and parafoveal ganglion cell complex, and short stature. Our findings expand the spectrum of the recently reported neurosensorial abnormalities and revealed the variable phenotype expressivity of CDK5RAP2 defect. Our study highlights the complexity of the genetic background of microcephaly/ID and the efficiency of the exome sequencing to provide an accurate diagnosis and to improve the management and follow-up of such patients.
