Microdeletion 10q26-syndrome – A rare cause for developmental retardation, strabismus and hypoplasia of cerebellum – A case report

Introduction: Microdeletion 10q26-syndrome is a rare disorder with so far 60 reported cases. Symptoms are developmental delay in language and motor skills and cognition deficits of variable degree, strabismus, typical facial features (broad nasal bridge, deep set eyes), microcephaly, growth retardation. Variable manifestations include feeding difficulties, behavior problems, muscular hypotonia, hearing impairment and anomalies of heart, genitals, kidney, palate, feet and hand. Variability in clinical manifestation can be explained with different length of deletion.

Patient and methods: We report on a 10 years old girl with moderate global developmental retardation, strabismus and mild ataxia and intentional tremor. Pregnancy complicated with premature labor. Birth at 41st weeks by cesarean delivery, APGAR 3/8/9. Development of length and weight according to 50^th centile. Growth of head circumference according to 10^th centile. Cranial MRI (3 y.): Hypoplasia of cerebellum. EEG was normal. Amino acids i.S., organic acids i.U., acylcarnitine, thyroid hormons, lactate and transferrin electrophoresis normal. MRI of lumbar spine: anomaly of bow closure L5/S1.

Results: Using micro-array-CGH technology a microdeletion of 6,92Mb in chromosomal band 10q26 was detected and this was confirmed by real-time PCR. The investigation of both parents by micro-array-CGH und real-time PCR was negative.

Conclusion: At the age of 10 this syndrome could be assigned to microdeletion 10q26-syndrome. Pathogenity is confirmed by size of deletion (>4 Mb) and „de novo“ appearance. So far 60 cases are published with typical symptoms. In our case a cerebellar hypoplasia was found additionally to typical symptoms causing ataxia and intentional tremor. These additional symptoms can most probably be explained by extended deletion beyond the typical 10q26 mikrodeletion region.