De novo complete trisomy 5p: clinical and neuroradiological findings.

Partial or complete duplication of 5p is a rare chromosomal abnormality in which genotype-phenotype correlation studies are hampered by other commonly associated chromosomal abnormalities. We report on a new patient in whom a complete de novo trisomy 5p in all metaphases represented the only chromosomal aberration. The present case further contributes to delineate the typical clinical picture of the trisomy 5p syndrome. Long-term clinical follow-up demonstrated low levels of secretory immunoglobulin A (IgA) on several occasions and likely related to the patient's recurrent respiratory infections (RRIs), a main clinical feature of the trisomy 5p syndrome. An extensive neuroradiological study detected a progressive triventricular hydrocephalus during the fist year of life with subsequent stabilization. Neuronal migration disorders were also present and probably account for the drug-resistant epilepsy presented by the patient.