This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urinary tract, Subject name: Pathology
Focal segmental glomerulosclerosis is characterized by? 
Select and explain. 
A. IgA +/- IgG, B. IgM and C3, C. Granular IgG and C3, D. Linear IgG and C3
B: IgM and C3
Answer: B: IgM and C3 
Explanation: Focal segmental glomerulosclerosis (FSGS) is characterized by sclerosis of some (but not all) glomeruli that involve only a pa of each affected glomerulus. The affected glomeruli exhibit increased mesangial matrix, obliterated capillary lumina, deposition of hyaline (hyalinosis) and foamy (lipid-laden) macrophages. In affected glomeruli, immunofluorescence microscopy often reveals nonspecific trapping of immunoglobulins, usually IgM, and complement in the areas of hyalinosis. On electron microscopy, the podocytes exhibit effacement of foot processes, as in minimal-change disease. Ref: ROBBINS BASIC PATHOLOGY 10th ed Pg no: 556