| Present | Presence of mesangial matrix expansion (estimated by light microscopic screening, verified by scoring according to images of mesangial matrix expansion with greater than 50% increase in mesangial volume compared to normal controls, using NIH Image or simi |
| Absent | Absence of mesangial matrix expansion (estimated by light microscopic screening, verified by scoring according to images of mesangial matrix expansion with greater than 50% increase in mesangial volume compared to normal controls, using NIH Image or simil |