RESUMO
OBJECTIVE: To describe the clinical presentation and long-term clinical features of a molecularly confirmed cohort with Cohen syndrome. STUDY DESIGN: Twelve patients with Cohen syndrome aged 0.2-13.9 years from 8 families with a median follow-up of 7 years were enrolled to the study. Genetic analyses were made by VPS13B and whole-exome sequencing analyses. RESULTS: Biallelic VPS13B variants, including 3 nonsense, 1 frameshift, and 1 splice-site variant, and a multiexon deletion were detected. Prader-Willi syndrome-like features such as hypotonia, small hands, round face with full cheeks, almond-shaped eyes, and micrognathia were observed in all infantile patients. Beginning from age 4 years, it was noticed that the face gradually elongated and became oval. The typical facial features of Cohen syndrome such as a long face, beak-shaped nose, and open-mouth appearance with prominent upper central incisors became evident at age 9. Other Cohen syndrome features including retinopathy (11/11), neutropenia (11/12), truncal obesity (5/12), and myopia (5/11) were detected at the median ages of 7.8, 7, 7.5, and 5 years, respectively. Eleven patients aged older than 5 years at their last examination had severe speech delay. CONCLUSIONS: A differential diagnosis of Cohen syndrome in the infancy should be made with Prader-Willi syndrome, and that the typical facial features for Cohen syndrome is prominent at age 9 years, when retinopathy, neutropenia, and truncal obesity become evident. Moreover, adding the severe speech delay to the diagnostic criteria should be considered.
Assuntos
Deficiência Intelectual , Transtornos do Desenvolvimento da Linguagem , Microcefalia , Miopia , Neutropenia , Síndrome de Prader-Willi , Degeneração Retiniana , Humanos , Criança , Hipotonia Muscular/diagnóstico , Hipotonia Muscular/genética , Proteínas de Transporte Vesicular/genética , Microcefalia/diagnóstico , Microcefalia/genética , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Degeneração Retiniana/genética , Miopia/diagnóstico , Miopia/genética , Obesidade/diagnóstico , Obesidade/genéticaRESUMO
Resumen Introducción: el Síndrome de Cohen es una enfermedad genética monogénica autosómica recesiva, que se origina a partir de mutaciones en el gen VPS13B (COH1). Se caracteriza por obesidad, retraso psicomotor, microcefalia, hipotonía, miopía progresiva, distrofia retiniana, neutropenia intermitente y rasgos faciales particulares. Objetivo: presentar el segundo caso reportado en Colombia, que fue confirmado mediante estudio molecular. También se presenta una breve revisión de la literatura médica más reciente sobre esta patología. Caso clínico: adolescente de 14 años con microcefalia, trastorno cognitivo, malformaciones menores asociadas, neutropenia y obesidad, con mutación homocigota del gen VPS13B. Conclusión: a pesar de ser un síndrome poco común, con importante variabilidad fenotípica, debe sospecharse con base en los criterios clínicos y en las patologías asociadas.
Abstract Introduction: cohen's syndrome is an autosomal recessive monogenic genetic disease, which originates from mutations in the VPS13B (COH1) gene. It is characterized by obesity, psychomotor retardation, microcephaly, hypotonia, progressive myopia, retinal dystrophy, intermittent neutropenia, and classic facial features. Objective: to present the second case reported in Colombia, which was confirmed by molecular study. A brief review of the most recent medical literature on this pathology is also presented. Clinical case: a 14-year-old adolescent with microcephaly, cognitive disorder, minor associated malformations, neutropenia, and obesity, with a homozygous VPS13B gene mutation. Conclusion: despite being a rare syndrome, with significant phenotypic variability, it should be suspected based on clinical criteria and associated pathologies.