Immune Complex Deposition in Certain Forms of Childhood Nephritis

Objectives: To verify the deposition of immune complexes in various types of childhood nephritis. Methods: This study was carried out in Middlesex Hospital, University Collage, London and AL-Hussein University Hospital, Cairo, during the period from Dec., 1996 to Nov., 1999. It included 52 patients with nephritis, selected according to certain inclusion criteria to be evaluated histopathologically for determining the intensity of immunoglobulin and complement deposition in the glomeruli as they have the most important role in glomerular injury and progression of the disease process in nephritis. After thorough clinical and laboratory evaluation of all cases, they were divided into three groups: lupus nephritis (20 cases), APSGN (18 cases) and IgA nephropathy (14 cases). Renal biopsies were done for all cases and examined by light, electron and immunofluorescence microscopy. Results: Our results showed that cases of lupus nephritis were subdivided into: stage II (3 cases), stage III (4 cases), stage IV (1 cases) and stage V (2 cases). There were various amounts of immune complex and complement deposition in all stages (IgG, IgA, IgM, C3, C4 & Cq1). Stage IV lupus nephritis showed the highest intensity of immune complex deposition especially IgG, IgM and C3. These deposits were more marked and more diffuse than in other stages. In APSGN showed marked significant deposits of all immune complexes except C1q. All cases of APSGN showed marked significant deposition of C3 (100%) and C4 (75%). The least was IgA and IgM (3&2 cases respectively). All IgA nephropathy patients showed immune deposits in the mesangium and along the capillary wall. IgA was predominantly deposited in all cases (100%) and the second predominant immune complex was C3 (78.6%). There was a strong correlation between intensity of immune complex deposits detected by IF microscopy and the ultrastructural changes found on electron microscopy examination. Also, the degree of immune deposits is related to the severity of nephritis and to the pattern of glomerular damage. Conclusions: We can conclude that immune complex deposits have both diagnostic and prognostic values for patients with nephritis.