Demographic Characteristics, Risk Factors, and Presenting Features of Children with Symptomatic Nutritional Rickets: A French Series

Aim: To describe the demographic characteristics, risk factors, and presenting features of children with symptomatic nutritional rickets in France. Methods: This is a retrospective study of 38 children diagnosed with nutritional rickets from 1998 to 2019. Results: We observed a higher frequency of rickets in males (74 vs. 26%), in young children (median age at diagnosis: 23 months; 82% were younger than 5 years), and in children with a non-Caucasian ethnic background (89%). Most children were exclusively breastfed (78%) without adequate vitamin D supplementation (89%). The most common presentations were bowed legs (63%), hypocalcemic seizures (21%), and growth retardation (11%). Approximately half (62%) of the children were hypocalcemic. The children presenting with hypocalcemic seizures were significantly younger (0.8 vs. 2.2 years; p = 0.041) and had lower total serum calcium levels (1.44 vs. 2.17 mmol/L; p < 0.0001), higher phosphatemia (1.43 vs. 1.23 mmol/L; p = 0.020), and lower 25-hydroxy vitamin D levels (3 vs. 7 ng/mL; p = 0.020) but similar parathyroid hormone levels (357 vs. 289 ng/mL; p = 0.940) compared to rickets cases who did not experience hypocalcemic seizures. A dilated cardiomyopathy was detected in 14% of the children who had undergone echocardiography. Conclusion: Nutritional rickets remains endemic in the pediatric population and its most severe forms can have life-threatening sequelae. Health practitioners need to be cognizant of these facts to raise awareness and screen high-risk populations.