Obesity in childhood and precocious puberty. Diagnostic difficulties

Precocious puberty (PP) requires a detailed diagnosis. It is concerned that the most useful parameter to differentiate central precocious puberty (CPP) from isolated mild variants is the bone age (BA). On the other hand, obesity can accelerate physical development. The aim of this study was to evaluate whether the coexistence of obesity in children with precocious puberty symptoms influences the diagnostic process. We retrospectively analyzed records of 200 children (F/M 164/36) hospitalized with PP suspicion. The analysis evaluated the nutritional status based on BMI percentile level, compatibility between the BA and the chronological age; and the final clinical diagnosis. In the analyzed group excessive body weight was found in 66 (33%) children – 34 were overweight, 32 obese. Children with excessive body weight were significantly more likely to have mild variants of precocious puberty (71% vs. 66.4%), despite the higher prevalence of accelerated bone age in this group (47% vs. 24.6%). In the group with mild variant of PP and accelerated BA (n = 41 (28.9%)) up to 75.6% of children were overweight or obese. In the group of CPP accelerated BA was observed only in 23 (52.3%) children. Frequently recognized variant of PP in obese children was premature pubarche (n = 20 (62.5%)). Obesity and overweight significantly modifies puberty, and by accelerating the BA can hinder the initial diagnosis of PP. The BA acceleration seems to be poor indicator of CPP, especially in obese children. Among overweight and obese children dominates mild variant of precocious puberty – premature pubarche.