摘要
Abstract
Objective To explore the clinical value of the renal phosphorus threshold(ratio of tubular maximum reabsorption of phosphate to glomerular filtration rate,TmP/GFR)in the diagnosis and treatment of children with X-linked hypophosphatemic rickets(XLH).Methods A retrospective study was conducted,including 83 children diagnosed with XLH at Children's Hospital of Nanjing Medical University from January 2010 to January 2023.Initial diagnosis and follow-up data were collected to investigate the correlation of TmP/GFR with the severity of rickets,calcium and phosphorus metabolism indicators,and the dosage of phosphate treatment.Children were divided into two groups based on the occurrence of renal calcification:the renal calcification group(n=47)and the non-renal calcification group(n=36).Clinical data between the two groups were compared.Multivariate logistic regression analysis was used to identify factors influencing renal calcification in XLH children.The predictive value of TmP/GFR for renal calcification in XLH children was evaluated using receiver operating characteristic(ROC)curves.Results In the 83 XLH children,the initial TmP/GFR was(0.78±0.21)mmol/L,with significant individual variation(range:0.28-1.24 mmol/L).TmP/GFR showed no significant correlation with the severity of rickets(P>0.05).Parathyroid hormone was negatively correlated with TmP/GFR(rs=-0.020,P=0.008),while blood phosphorus(rs=0.384,P<0.001),blood calcium(rs=0.251,P<0.001),and 25-hydroxyvitamin D(rs=0.179,P<0.001)were positively correlated with TmP/GFR.No significant correlation was found between TmP/GFR and alkaline phosphatase(rs=-0.002,P=0.960)or phosphate treatment dosage(rs=0.012,P=0.800).Blood calcium and TmP/GFR levels were significantly lower in the renal calcification group than in the non-renal calcification group(P<0.05),while parathyroid hormone and urine calcium levels were significantly higher in the renal calcification group(P<0.05).Multivariate logistic regression analysis indicated that TmP/GFR and urine calcium levels were closely associated with renal calcification in XLH children(P<0.05).ROC curve analysis revealed that the areas under the curve for TmP/GFR,urine calcium,and their combined detection predicting renal calcification in XLH children were 0.696,0.679,and 0.761,respectively.Conclusions TmP/GFR may serve as an important diagnostic indicator for pediatric XLH;however,it does not reflect the severity or activity of rickets and cannot be used to judge the efficacy of traditional treatment.Urine calcium and TmP/GFR are valuable predictors for renal calcification in XLH children.关键词
X-连锁低磷性佝偻病/肾磷阈/肾钙质沉着症/儿童Key words
X-linked hypophosphatemic rickets/Renal phosphorus threshold/Renal calcification/Child
