Alicia Mirás1, Antonio Freire Corbacho2, Javier Rodríguez García2, Rosaura Leis3, Luís Aldámiz-Echevarría4, José M Fraga1, María L Couce5. 1. Unidad de Diagnóstico y Tratamiento de Enfermedades Metabólicas Congénitas, Servicio de Pediatría, Hospital Clínico Universitario de Santiago de Compostela, Santiago de Compostela, A Coruña, España. 2. Servicio de Laboratorio Central, Hospital Clínico Universitario de Santiago de Compostela, Santiago de Compostela, A Coruña, España. 3. Unidad de Gastroenterología y Nutrición, Servicio de Pediatría, Hospital Clínico Universitario de Santiago de Compostela, Santiago de Compostela, A Coruña, España. 4. Unidad de Metabolismo, Departamento de Pediatría, Hospital de Cruces, Barakaldo, Vizcaya, España. 5. Unidad de Diagnóstico y Tratamiento de Enfermedades Metabólicas Congénitas, Servicio de Pediatría, Hospital Clínico Universitario de Santiago de Compostela, Santiago de Compostela, A Coruña, España. Electronic address: maria.luz.couce.pico@sergas.es.
Abstract
BACKGROUND AND OBJECTIVE: Mineral bone disease is more common in phenylketonuric patients. The objectives of this study were to determine the usefulness of biochemical bone markers to identify phenylketonuric patients with mineral bone disease (MBD) and know the underlying bone remodeling alterations. PATIENTS AND METHOD: Cross-sectional study of 43 phenylketonuric patients>7 years (range: 7.1-41 years). A nutritional survey was performed and bone alkaline phosphatase (BAP), procollagen type 1 N-terminal propeptide (PNP-1), beta-crosslaps and ratio calcium/creatinine in urine were determined. RESULTS: A percentage of 20.9 of patients had pathological biochemical bone markers, 90% of them being adults. BAP was decreased in 70% of them and beta-crosslaps in 42.8%. BAP values were more often pathological in phenylketonuric patients with a late diagnosis (41.7 vs. 10.7%; P<.05) and in patients with MBD (60 vs. 14.3%; P<.05). PNP-1 values and calcium/creatinine were similar among all phenylketonuric patients regardless of presenting MBD, late diagnosis or tetrahydrobipterin treatment (enzyme cofactor). Patients with decreased BAP and beta-crosslaps had lower natural protein intake: BAP (0.21 ± 0.13 vs. 0.65 ± 0.65 g/kg; P<.05); beta-crosslaps (0.29 ± 0.23 vs. 0.65 ± 0.66 g/kg; P<.05). None of the tetrahydrobiopterin treated patients showed altered values of BAP, PNP-1 or calcium/creatinine. CONCLUSIONS: Adult phenylketonuric patients with lower natural protein intake tend to have lower values of BAP, which is a marker that may be useful to identify patients at risk for MBD.
BACKGROUND AND OBJECTIVE:Mineral bone disease is more common in phenylketonuricpatients. The objectives of this study were to determine the usefulness of biochemical bone markers to identify phenylketonuricpatients with mineral bone disease (MBD) and know the underlying bone remodeling alterations. PATIENTS AND METHOD: Cross-sectional study of 43 phenylketonuricpatients>7 years (range: 7.1-41 years). A nutritional survey was performed and bone alkaline phosphatase (BAP), procollagen type 1 N-terminal propeptide (PNP-1), beta-crosslaps and ratio calcium/creatinine in urine were determined. RESULTS: A percentage of 20.9 of patients had pathological biochemical bone markers, 90% of them being adults. BAP was decreased in 70% of them and beta-crosslaps in 42.8%. BAP values were more often pathological in phenylketonuricpatients with a late diagnosis (41.7 vs. 10.7%; P<.05) and in patients with MBD (60 vs. 14.3%; P<.05). PNP-1 values and calcium/creatinine were similar among all phenylketonuricpatients regardless of presenting MBD, late diagnosis or tetrahydrobipterin treatment (enzyme cofactor). Patients with decreased BAP and beta-crosslaps had lower natural protein intake: BAP (0.21 ± 0.13 vs. 0.65 ± 0.65 g/kg; P<.05); beta-crosslaps (0.29 ± 0.23 vs. 0.65 ± 0.66 g/kg; P<.05). None of the tetrahydrobiopterin treated patients showed altered values of BAP, PNP-1 or calcium/creatinine. CONCLUSIONS: Adult phenylketonuricpatients with lower natural protein intake tend to have lower values of BAP, which is a marker that may be useful to identify patients at risk for MBD.
Authors: María José de Castro; Carmela de Lamas; Paula Sánchez-Pintos; Domingo González-Lamuño; María Luz Couce Journal: Nutrients Date: 2020-07-20 Impact factor: 5.717