Klinefelter’s Syndrome: 18 years’ experience of a pediatric <br><b>Abstract in English</b>

Abstract

AIMS: To describe the clinical characteristics of children and adolescents with Klinefelter Syndrome. METHODS: A cross-sectional retrospective study was conducted, based on clinical data of patients diagnosed with Klinefelter Syndrome and followed from January 1992 to December 2009 (18 years) at a Pediatric Endocrinology Unit of a tertiary care-level hospital in Portugal. RESULTS: In the study period 15 patients were identified. Seven had a positive prenatal diagnosis of Klinefelter Syndrome and eight had post-natal diagnosis, after investigation for psychomotor development delay, behavioral disruptions and/or suggestive phenotype (four of them only diagnosed during adolescence). Thirteen patients had a peripheral blood karyotype of 47, XXY and two presented 47, XXY/46, XY mosaicism. The median age of first visit was seven years. Onset of puberty occurred spontaneously in seven cases. Puberty induction was performed in three patients, at age of 14 years. Those who needed hormone treatment had an effective response with no side effects. Behavioral and social inadequacies were identified in two cases and moderate global motor developmental delay in nine. Hyperactivity and attention deficit disorder were diagnosed in five patients, currently treated with methylphenidate. CONCLUSIONS: A global motor development delay together with physical features of Klinefelter Syndrome in a child justifies karyotyping given the high prevalence of this syndrome, especially if socialization problems and learning difficulties are present. This study highlights the need for greater awareness in diagnosis as well as the importance of multidisciplinary approach in the care and education of these patients.