The Frequency of Genetic Mutations in Pediatric Patients Diagnosed with Nephrotic Syndrome: A Single-Center Retrospective Study in Saudi Arabia.

Abstract

Limited data are available on the common genetic mutations causing nephrotic syndrome (NS) in the Saudi pediatric population. We therefore conducted this study to estimate the frequency of genetic mutations in pediatric patients diagnosed with NS. We conducted this retrospective cross-sectional study at a single center in Riyadh, Saudi Arabia. The data of pediatric patients diagnosed with NS from 2015 to 2019 were reviewed. Percentages were calculated for categorical variables such as gender and mutant gene. We identified a total of 206 patients diagnosed with NS during the study. Molecular genetic profiling was performed only for 35 patients who met the inclusion criteria. Female patients represented 42.8% of all cases (n = 15). The median age of the patients at diagnosis was 36 months (interquartile range 12-72). Associated anomalies were recognized in 37.14% of the patients (n = 13). Out of the 35 patients, 19 had positive molecular genetic results. Consanguinity was present in 18 (51.42%) of these patients. The most common homozygous mutation detected was PLCE1 (42.1%; n = 8), followed by NPHS1 (26.32%; n = 5). Heterozygous mutations were detected in three children (15.8%). Complement factor B and WT1 mutations accounted for one patient each and both COL4A5 and INF2 mutations were reported in a single child. Two mutant genes of unknown zygosity - CD151 and COL4A3 were also identified. PLCE1 is a major underlying cause of NS. PLCE1 may cause diffuse mesangial sclerosis in the kidney with early-onset NS and a poor prognosis.