The results demonstrate that glomerular MO infiltration is an independent predictor of worse outcomes posttransplant following acute renal allograft rejection.

No abstract

Isolated endarteritis of kidney transplants is increasingly recognized. Notably, microarray studies revealed absence of immunologic signatures of rejection in most isolated endarteritis biopsy samples. We investigated if isolated endarteritis responds to rejection treatment and affects kidney transplant survival. We retrospectively enrolled recipients of kidney transplant who underwent biopsies between 1999 and 2011 at seven American and Canadian centers. Exclusion criteria were recipients were blood group-incompatible or crossmatch-positive or had C4d-positive biopsy samples. After biopsy confirmation, patients were divided into three groups: isolated endarteritis (n=103), positive controls (type I acute T cell-mediated rejection with endarteritis; n=101), and negative controls (no diagnostic rejection; n=103). Primary end points were improved kidney function after rejection treatment and transplant failure. Mean decrease in serum creatinine from biopsy to 1 month after rejection treatment was 132.6 mmol/L (95% confidence interval [95% CI], 78.7 to 186.5) in patients with isolated endarteritis, 96.4 mmol/L (95% CI, 48.6 to 143.2) in positive controls (P=0.32), and 18.6 mmol/L (95% CI, 1.8 to 35.4) in untreated negative controls (P,0.001). Functional improvement after rejection treatment occurred in 80% of patients with isolated endarteritis and 81% of positive controls (P=0.72). Over the median 3.2-year followup period, kidney transplant survival rates were 79% in patients with isolated endarteritis, 79% in positive controls, and 91% in negative controls (P=0.01). In multivariate analysis, isolated endarteritis was associated with an adjusted 3.51-fold (95% CI, 1.16 to 10.67; P=0.03) risk for transplant failure. These data indicate that isolated endarteritis is an independent risk factor for kidney transplant failure.

A number of clinical laboratory and biopsy-derived parameters were assessed for their prognostic significance in the short (24 months), intermediate (60 months) and long terms in 45 patients (43 female, 2 male) with diffuse proliferative lupus glomerulonephritis (DPGN). The factors evaluated were serum creatinine (SCr) and urinary protein at time of biopsy, initial dose of prednisone and immunosuppressive after biopsy, activity index (AI), chronicity index (CI), their individual components, extent of extraglomerular (tubulo-interstitial) immune deposits (EGD) and mean number of intraglomerular monocytes per glomerulus (NSE index). Using proportional hazards analysis to evaluate the parameters, SCr (P = 0.003), AI (P = 0.005) and NSE index (P = 0.038) were shown to be significant predictors of outcome when all variables except the components of AI and CI were considered. When AI and CI were omitted but their components included, SCr (P = 0.0005), NSE index (P = 0.024), extent of karyorrhexis (P = 0.035) and glomerulosclerosis (P = 0.033) were then demonstrated to be significant prognostic factors of DPGN. The results suggest that intraglomerular monocyte infiltration has a protective effect and confirm that AI index is a relatively powerful predictor of outcome. Histologic and nonhistologic biopsy factors contribute significant additional prognostic information to that provided by SCr.

The significance of the finding of focal glomerulosclerosis (FGS) in idiopathic membranous glomerulonephritis (MGN) is uncertain. Twenty-seven patients with mixed FGS and MGN (MGN-FGS) were compared to 25 patients with MGN alone (generally matched for age, sex and stage of glomerular lesion) with respect to pathology, presenting clinical and laboratory features, and course of disease. Biopsies from the MGN-FGS patients showed significantly more extensive tubulointerstitial disease (P less than 0.001) than did those with MGN alone. At the time of biopsy, the MGN-FGS group had a significantly higher proportion of patients with hypertension (P = 0.006) and microhematuria (P = 0.006), a marginally higher percentage of patients with the nephrotic syndrome (P = 0.051), and a greater mean 24-hour urinary protein excretion (P = 0.004). A similar proportion of patients in each group were treated with either prednisone alone or prednisone with an immunosuppressive. Forty-eight percent of MGN-FGS patients and 13% of the MGN patients developed established renal failure in the follow-up period (P = 0.008). The renal survival rate for the MGN-FGS group was significantly lower at 24 months (0.61 vs. 0.93, P less than 0.05), 60 months (0.48 vs. 0.88, P less than 0.025), and over the entire follow-up period (P less than 0.05). The results indicate that FGS in MGN is associated with a significantly poorer prognosis than MGN without this lesion.

No abstract

Recent evidence suggests a role for lipid deposition in the pathogenesis of some forms of glomerular disease. To gain further insight into this phenomenon guinea pigs (GP) were fed a 2% cholesterol (HC) diet and compared to GP on a normal diet (C). Serial observations were made 5, 10, 30 and 70 days after the initiation of the experiment. HC gained less weight than C (P less than 0.001) and developed hemolytic anemia after 30 days. At all time periods serum total cholesterol (TC) was significantly elevated in HC (P less than 0.001). High density lipoprotein-cholesterol and total phospholipids (PL) were significantly higher in HC at days 30 and 70. Lipoprotein-X was detected in HC serum. The relative proportion (%) of cholesteryl ester (CE) at day 70 was significantly higher in HC than in C when renal cortical lipids were analyzed (P less than 0.017). Renal function was normal in both groups throughout the 70 days. The HC group developed proteinuria and hematuria (proteinuria, HC = 22.1 +/- 7.2 mg/24 hr; C, 6.4 +/- 2.3 mg/24 hr), which was detected at day 70 but not at day 30. HC developed significant progressive mesangial expansion which was first evident at day 30. In HC only oil red 0 material was first detected in glomeruli at day 5 and was very conspicuous at day 70. Increased intraglomerular monocyte numbers were detected at day 70 (P less than 0.017) but not at day 30 in HC. No glomerulosclerosis was observed in GP's with drug-induced hemolysis on a normal diet. To see the effect of high protein intake on HC GP's, a group of GP's was put on a HC diet for 30 days followed by a 2% cholesterol-high protein (HCHP) diet for 40 days. Compared to HC GP's, the HCHP group showed significantly higher serum TC and PL (P less than 0.017), mesangial expansion (P less than 0.01) and proteinuria (P less than 0.01). The results indicate that hypercholesterolemia plays an important role in the pathogenesis of glomerulosclerosis in this model and that the process appears to be mediated, at least in part in the later stages, by monocytes. The addition of protein to the HC diet augments these effects.

It has been recently suggested that focal glomerulosclerosis (FGS) is analogous to atherosclerosis. Obese Zucker (OZ) rats spontaneously develop hyperlipidemia, proteinuria and FGS. To evaluate the role of the monocyte (MO) and its derivatives in the pathogenesis of the lesion, 30 OZ rats and 15 lean littermates (LZ) were followed for up to 240 days of age. At 75,120 and 240 days of age, groups of 10 OZ and 5 LZ were assessed with respect to serum total and free cholesterol (TC and FC), triglyceride, lipoprotein electrophoresis, renal histology, histochemistry and immunohistochemistry. All serum lipids were raised at 75 days in OZ rats and increased progressively at 120 and 240 days. The early lesions of FGS were first demonstrated in OZ at 120 days with more advanced lesions at 240 days. FGS was seen in LZ only at 240 days when their serum lipids were raised. Intraglomerular MO infiltration was significantly higher in OZ than in LZ at all time periods (p < 0.01) and greater in glomeruli with FGS lesions than in those without (p < 0.01 and 120 days and p < 0.05 at 240 days). Staining for ED1 and la antigens with monoclonal antibodies demonstrated increasing numbers of intraglomerular ED1⁺ and Ia⁺ cells with increasing age and extent of FGS. The findings suggest a role for intraglomerular macrophages in the pathogenesis of FGS in OZ.