Khalighi Mazdak A, Al-Rabadi Laith, Chalasani Meghana, Smith Mark, Kakani Siddhartha, Revelo Monica P, Meehan Shane M
Department of Pathology, University of Utah, Salt Lake City, Utah, USA.
Department of Nephrology, University of Utah, Salt Lake City, Utah, USA.
Kidney Int Rep. 2018 Jun 2;3(5):1128-1134. doi: 10.1016/j.ekir.2018.05.010. eCollection 2018 Sep.
Staphylococcal infection-related glomerulonephritis (GN) has been shown to represent a unique form of infection-related GN that contains IgA-dominant deposits and is often seen concurrently with the bacterial infection. Biopsies commonly reveal an endocapillary proliferative and/or exudative or mesangial proliferative GN. Rare cases have been reported to show cryoglobulin-like features, including hyaline pseudothrombi and wireloop deposits; however, detailed characterization of these cases is lacking.
The pathology archives from the University of Utah and Sharp Memorial Hospital were reviewed from January 2016 to September 2017 in search of cases with GN containing IgA-dominant deposits and features of cryoglobulinemia.
Of 1965 native kidney biopsies, 5 showed IgA-dominant GN with cryoglobulinemic features. All patients had active staphylococcal infections at the time of biopsy. All presented with acute kidney injury (serum creatinine range: 1.7-6 mg/dl), and all had proteinuria and hematuria. All biopsies showed exudative GN, and 4 biopsies had focal crescents. All had focally prominent hyaline pseudothrombi with or without wireloop deposits, and all showed co-dominant staining for IgA and C3 on immunofluorescence microscopy. Serologic testing for cryoglobulinemia was performed in 3 patients and was transiently positive in 1 patient. Four patients required hemodialysis at last follow-up, whereas 1 patient returned to baseline kidney function.
IgA-dominant GN with cryoglobulinemic features is an uncommon but severe form of glomerular injury in patients with staphylococcal infections. Four of 5 patients had crescentic glomerular injuries, all of whom required hemodialysis at last follow-up. Patients with IgA-dominant GN with features of cryoglobulinemia should be evaluated for active staphylococcal infection.
葡萄球菌感染相关的肾小球肾炎（GN）已被证明是一种独特的感染相关GN形式，其含有以IgA为主的沉积物，且常与细菌感染同时出现。活检通常显示毛细血管内增生性和/或渗出性或系膜增生性GN。据报道，罕见病例表现出冷球蛋白血症样特征，包括透明假血栓和线圈样沉积物；然而，这些病例的详细特征尚缺乏。
回顾了犹他大学和夏普纪念医院2016年1月至2017年9月的病理档案，以寻找具有以IgA为主的沉积物和冷球蛋白血症特征的GN病例。
在1965例原发性肾活检中，5例显示具有冷球蛋白血症特征的以IgA为主的GN。所有患者在活检时均有活动性葡萄球菌感染。所有患者均表现为急性肾损伤（血清肌酐范围：1.7 - 6mg/dl），且均有蛋白尿和血尿。所有活检均显示渗出性GN，4例活检有局灶性新月体形成。所有病例均有局灶性显著的透明假血栓，伴或不伴有线圈样沉积物，免疫荧光显微镜检查均显示IgA和C3共显性染色。3例患者进行了冷球蛋白血症的血清学检测，1例患者呈短暂阳性。在最后一次随访时，4例患者需要血液透析，而1例患者肾功能恢复至基线水平。
具有冷球蛋白血症特征的以IgA为主的GN是葡萄球菌感染患者中一种罕见但严重的肾小球损伤形式。5例患者中有4例有新月体性肾小球损伤，所有这些患者在最后一次随访时均需要血液透析。对于具有冷球蛋白血症特征的以IgA为主的GN患者，应评估是否存在活动性葡萄球菌感染。
