Bone Densitometry in a Cohort of Egyptian Children with Steroid Sensitive Nephrotic Syndrome.

Document Type : Original Article

Authors

1 Department of Pediatrics, Pediatric Nephrology Unit, Faculty of Medicine, Cairo University, Egypt.

2 Department of Radiology, Faculty of Medicine, Cairo University, Egypt.

3 Ministry of Health, Cairo, Egypt.

Abstract

Introduction
Nephrotic syndrome is one of the most frequent glomerular diseases among children. Steroid therapy is still the standard treatment of this disease. 
 
Aim of the Study
This study aims to assess bone density in children with steroid sensitive nephrotic syndrome (SSNS) and to correlate the degree of bone density affection to steroid dose and duration. 
 
Methods
Fifty children with SSNS [25 steroid dependent/ frequent relapsing (SDNS/FRNS) and 25 infrequently relapsing (IFRNS) patients] were assessed clinically and laboratory. Bone mineral density (BMD) was measured to all included patients by Duel energy X-ray absorptiometry. 
 
Results
BMD abnormality is significantly increased in SDNS/FRNS group than IFRNS group (p = 0.0001). BMD Z score negatively correlated with relapse frequency-/year [p = 0.001 and correlation coefficient (CC) = -0.586]. Bone ache was the only significant complaint in patients with abnormal BMD (p = 0.004). Significant negative correlation was found between BMD Z score and each of serum alkaline phosphatase (ALP) level and Levamisol therapy duration   (p < 0.05 & CC = -0.549,    
-0.576 respectively). The best cut off point between patients with normal BMD and abnormal BMD regarding cumulative steroid dose was found to be > 8329.4 mg/m2 with sensitivity of 85% and specificity of 96.67% and area under curve (AUC) of 0.92.
 
Conclusion
Impaired BMD in SSNS children significantly correlates with frequency of relapses, serum alkaline phosphatase level, Levamisol therapy duration, steroid doses and duration. At a cumulative steroid dose > 8329.4 mg/m2, BMD impairment is predicted with sensitivity 85% and specificity 97%.
 

Keywords

Main Subjects