Malformazioni congenite nei nati residenti nel Comune di Gela (Sicilia, Italia). Congenital malformations in newborns residing in the Municipality of Gela (Sicily, Italy)

OBJECTIVE: to conduct an epidemiological descriptive study on malformed newborns residing in the Municipality of Gela during 1991-2002 to compare theprevalences observed with those reported by the registries operating in Sicily, in Italy and in the scientific literature. DESIGN AND SETTING: epidemiological descriptive study in the area of the Municipality of Gela, (Sicily, Italy). MATERIALS: information on congenital anomalies occurred in livebirths and stillbirths residing in the Municipality of Gela were obtained from different sources: local hospital statistics, general paediatricians list of patients, the Sicilian Registry of Congenital Malformations (ISMAC), hospital discharge records of Catania University Hospital, previous investigation data, the Gela Hospital Obstetrics Department archive. RESULTS: 520 malformed cases out of 13060 newborns were ascertained, accounting for a prevalence rate of 398/10000 total births, approximately 2 times significantly higher than those reported by the Sicilian Registry ISMAC (182/10000) and the Italian registries (205/10000). The annual distribution resulted significantly heterogeneous for all malformed cases and for cardiovascular, limb and external genitalia malformations. Significant excesses for anomalies of central nervous system, cardiovascular system, urinary tract, digestive, teguments and total malformations were found, with observed/expected ratios ranging from 1.5 to 6.0 or from 1.3 to 3.4 when compared with ISMAC or Italian registries respectively. When specific malformations where analysed, significant excesses for male hypospadias and diaphragmatic hernia were found. The occurrence of hypospadias, 56.7/10000 births, was 2.5 times significantly higher than the reference rates. CONCLUSION: the observed hypospadias birth rate is amongst the most elevated ever reported in literature. A low diagnostic specificity (many false positives) may explain the relevant increase of newborns diagnosed with microcephaly. Results reinforce the hypothesis ofa causal role of risk factors present in the Gela area on the etiology of malformations and address the need for further insights into the excesses found, for consolidation of the registration action andfor implementation of a health and environment local surveillance system able to monitor sensitive diseases in areas considered at environmental risk. A retrospective case-control study on disease excesses is being completed.