[Clinical heterogeneity of the chromosome 22q11 microdeletion syndrome].

BACKGROUND

DiGeorge anomaly, velocardiofacial syndrome and conotruncal anomaly face syndrome are part of a group of congenital malformations of the chromosome 22q11 microdeletion syndrome, since they share certain phenotypic features as well as a common genetic abnormality. The malformations include mild facial dysmorphic features, conotruncal heart defects, thymic and parathyroid hypoplasia or aplasia and cleft palate.

AIM: To describe the initial clinical presentation of children with clinical and molecular diagnosis of 22q11 microdeletion.

PATIENTS AND

METHODS

Ten children (seven male) with the phenotypic features of 22q11 microdeletion syndrome are reported. Microdeletion was detected in peripheral lymphocytes by fluorescent in situ hybridisation (FISH) with the TUPLE-1 DNA probe.

RESULTS

Two children had abnormal karyotypes, one of them had a visible deletion and another child had an unbalanced translocation inherited from his mother who had a balanced translocation between chromosomes 14 and 22. Two of the 10 patients had an anterior laryngeal web, a malformation infrequently described in this syndrome. Five patients had the diagnosis of DiGeorge anomaly, had a more serious clinical presentation and a higher early mortality.

CONCLUSIONS

The high frequency of the 22q11 microdeletion syndrome, estimated at 1:5.000 newborns, and its variable presentations requires a high level of awareness for its early diagnosis and appropriate management of associated complications.