C3 glomerulonephritis of children and literatures review

Abstract

Objective To study the clinical and pathological features of three children with C3 glomerulonephritis (C3GN) and summarize the relevant literatures to improve the levels of cognition and diagnosis of C3GN in children for clinician. Methods From November 2015 to March 2017, three children with C3GN who were hospitalized in Children′s Nephrology Center in First Affiliated Hospital of Sun Yat-sen University, were chosen as study subjects. Clinical manifestations, renal pathology, gene test results, treatment and prognosis of 3 cases of C3GN children were retrospectively analyzed, and summarized clinical characteristics of C3GN with the related literatures of C3 glomemlopathy (C3G) at home and abroad. Results Study results of 3 cases of C3GN were as follows. ①Clinical manifestations: hematuria and proteinuria were the first performance in 2 cases, and hematuria was the first performance in another case. Two cases had upper respiratory infections duration 1 week before onset of the disease, with high level of antistreptolysin (AS)O and level of serum complement C3 decreased.One case with acute kidney injury at onset. ②Renal biopsy pathological examination results: immunofluorescence only observed high intensity of complement C3 deposition (+ + to + + + ) in the mesangial area in 3 cases. Light microscopy showed that mesangial proliferative in 1 case, glomerular capillary hyperplasia with crescent formation in 1 case, and mild mesangial hyperplasia in another case. All 3 cases presented electron dense depositional under electron microscope. ③Gene test results of two cases who took genetic test: one of them was found C3 gene heterozygous mutation, and no mutation was found for the other one. ④Treatment and prognosis: 1 C3GN child only took symptomatic treatment; the other two cases were treated with hormone therapy, and combined with anticoagulants or angiotensin converting enzyme inhibitor (ACEI). They were followed up for 8 months to 13 months after treatment, one case had good prognosis with normal urine routines, renal functions and level of serum complement C3. While the other two cases were presented with persistent microscopic hematuria and low levels of serum complement C3, moreover one of them still had proteinuria. ⑤There were 3 related literatures of C3G were searched from database with a total of 28 C3G children, and with 3 cases of C3GN in this study, it can be summarized that C3G often occured in school age children, both male and female can be attacked and often with upper respiratory tract infection before onset. The main clinical manifestations were hematuria, proteinuria and low level of serum complement C3, some children may had edema, hypertension, ASO level increased and renal injury. Conclusions The clinical manifestations of C3GN are similar to acute poststreptococcal glomerulonephritis (APSGN), differential diagnosis of them mainly depends on renal biopsy for pathological examination results. It′s urgent to find out more convenient and effective examinations and therapy to help early diagnosis and improve prognosis of C3GN children. Key words: Glomerulonephritis; Streptococcus; Complement C3; Child