Document Type : original article

Authors

1 Children’s Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran. Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran.

2 Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran.

3 Children’s Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran. Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran

4 Growth and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran. Department of Pediatrics, Tehran University of Medical Sciences, Tehran, Iran. Maternal, Fetal & Neonatal Research Center, Family Health

10.22038/ijp.2024.77230.5418

Abstract

Objectives: Factors like low-protein diet may impose phenylketonuria (PKU) patients to impaired skeletal disease. The present study assessed the status of bone mineral density (BMD) among PKU patients on a low-protein diet.

Methods: A cross-sectional study was conducted (Tehran, Iran, 2019). Patients aged ≥ 4 years old with a definite diagnosis of PKU on a low-protein diet were included. BMD values of the lumbar spine and femoral neck were assessed. The primary objective was assessing femoral and lumbar BMD status in PKU patients.

Results: Forty-one PKU patients entered the study. The mean BMI was 20.712±4.833 Kg/m2. The mean bone age was significantly lower than chronological age (10.9 vs. 12.4 years; P=0.008). The results showed a bone mass reduction in 23.1% of all patients. A significant correlation was observed between lumbar and femoral BMD values (P=0.001; Pearson coefficient of correlation=0.516). Most patients (about 77%) had lumbar Z-scores>-1 and 10.3% showed Z-scores in the range of osteoporosis. Age (P=0.004) and age at diagnosis (P=0.002) were the influencing factors on BMD status. The results showed a significantly inverse correlation between BMD lumbar levels with the patient’s chronological age (P=0.016), age of PKU diagnosis (P=0.002), and phenylalanine level (P=0.025)

Conclusion: The results delineated impaired skeletal status among PKU patients on a low-protein diet. Lumbar Z-score values inversely correlated with a patient’s chronological age, age at PKU diagnosis, and phenylalanine level. Hence, early PKU diagnosis and treatment during neonatal period, as well as controlling phenylalanine concentration may improve BMD status.

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