Dalvin Lauren A, Fervenza Fernando C, Sethi Sanjeev, Pulido Jose S
Departments of *Ophthalmology †Nephrology and Hypertension ‡Anatomic Pathology, and §Molecular Medicine, Mayo Clinic, Rochester, MN.
Retin Cases Brief Rep. 2016 Winter;10(1):72-8. doi: 10.1097/ICB.0000000000000164.
Membranoproliferative glomerulonephritis (MPGN) classification has been changed from purely anatomic to molecular. This report describes two cases of MPGN with associated drusen that exemplify the importance of this change and the need for ophthalmologists to understand it.
The medical and pathologic records of two patients with MPGN and drusen were examined.
Two patients with MPGN and risk-associated alleles of complement factor H were found to have drusen. In one case, the process led to severe visual impairment. Based on anatomic classification, one patient had MPGN Type I and the other had MPGN Type III. However, both patients had renal biopsy findings classic for C3 glomerulonephritis and the same genetic abnormality (risk-associated alleles of complement factor H).
The association of MPGN and drusen needs to be reevaluated. Previously only recognized in association with Type II MPGN, drusen have been demonstrated in 2 patients with C3 glomerulonephritis in this report. These drusen are likely the result of complement pathway abnormalities. The authors propose a new nomenclature in the ophthalmic literature to classify pathology as immune complex-mediated or complement-mediated rather than solely by the electron microscopy findings. This nomenclature will better characterize the underlying genetic abnormalities and pathophysiology of these disease processes.
膜增生性肾小球肾炎（MPGN）的分类已从单纯的解剖学分类转变为分子分类。本报告描述了两例伴有玻璃膜疣的MPGN病例，例证了这种转变的重要性以及眼科医生了解它的必要性。
检查了两名患有MPGN和玻璃膜疣患者的医学和病理记录。
两名患有MPGN且带有补体因子H风险相关等位基因的患者被发现有玻璃膜疣。在其中一例中，该过程导致了严重的视力损害。基于解剖学分类，一名患者为I型MPGN，另一名为III型MPGN。然而，两名患者的肾活检结果均为C3肾小球肾炎的典型表现，且存在相同的基因异常（补体因子H风险相关等位基因）。
MPGN与玻璃膜疣的关联需要重新评估。玻璃膜疣此前仅被认为与II型MPGN有关，而在本报告中，两名C3肾小球肾炎患者也出现了玻璃膜疣。这些玻璃膜疣可能是补体途径异常的结果。作者在眼科文献中提出了一种新的命名法，将病理学分类为免疫复合物介导或补体介导，而不是仅根据电子显微镜检查结果。这种命名法将更好地描述这些疾病过程的潜在基因异常和病理生理学。
