IgA-dominant postinfectious glomerulonephritis: a report of 13 cases with common ultrastructural features

A unique form of postinfectious glomerulonephritis characterized by IgA-dominant immune complex deposits was recently described by Nasr et al (Hum Pathol. 2003;34:1235-1241), each case after a Staphylococcus infection in diabetic patients. Others have described glomerulonephritis with IgA-containing immune complex deposits in association with staphylococcal infections, although their histology was more varied and electron microscopy often did not to show large subepithelial deposits (“humps”) typical of postinfectious glomerulonephritis. In this report, we describe demographic, clinical, and renal biopsy findings in 13 cases of IgA-dominant postinfectious glomerulonephritis, each characterized by subepithelial humps at various stages of resolution. All patients presented with renal insufficiency (mean serum creatinine ± SD, 4.4 ± 2.7 mg/dL), hematuria (macroscopic in 3), and proteinuria (nephrotic range in 6). Based on histology and electron microscopy, postinfectious glomerulonephritis was classified as acute in 2 patients, subacute in 3, and resolving/persistent in 8. There were 6 patients who had recent Staphylococcus aureus infections (3 methicillin resistant), 5 who were diabetic, and 3 with nephropathy. A total of 4 patients (3 with serum creatinine >8.0 mg/dL at biopsy) developed end-stage renal disease, whereas 9 had a mean serum creatinine of 2.0 ± 1.1 mg/dL (range, 0.8-4.4) at 10 ± 13 months (range, 2-44) after biopsy. In summary, IgA-dominant postinfectious glomerulonephritis resembles poststreptococcal glomerulonephritis in its histologic spectrum and electron microscopy findings, is often associated with staphylococcal infections, occurs in diabetics and nondiabetics, and may resolve if renal failure at presentation is not severe.     

IgA-IgM nephropathy. A subgroup of primary mesangial glomerulonephritis

The renal biopsy material of Tampere University Central Hospital comprises 1992 renal biopsy specimens, accessioned during the years 1978-1989. Among these, there were three cases of mesangial glomerulonephritis with a peculiar type of immunofluorescent reactivity. Striking mesangial deposits of both IgA and IgM were found in glomeruli, whereas C3 deposits were absent or present in slight amounts. The light microscopic findings ranged from mild mesangial glomerulonephritis to more advanced forms of sclerosing glomerulopathy. Electron microscopic examination disclosed an increase of mesangial matrix, together with mesangial and paramesangial electron-dense deposits. Two of the patients had microscopic hematuria associated with proteinuria, and one had isolated proteinuria. The authors propose that this group of cases may represent a new subgroup of primary mesangial glomerulonephritis that has not been described previously. They differ immunohistologically from both IgA nephropathy and IgM nephropathy, and therefore could be designated as IgA-IgM nephropathy.     

Acquired glomerular lesions in patients with Down syndrome

The long-term survival of persons with Down syndrome has dramatically increased over the past 50 years. There are no studies addressing the spectrum of glomerular lesions in these patients. We reviewed the clinical-pathologic characteristics of 17 patients with Down syndrome who underwent renal biopsy. The cohort consisted of 12 whites and 5 African Americans with mean age of 29 years (range, 6-45 years). History of hypothyroidism was present in 8 patients. Renal presentations included renal insufficiency (15 patients, mean serum creatinine 3.4 mg/dL), proteinuria (all patients, including 3 with nephrotic syndrome, mean 24-hour urine protein 4.2 g), and hematuria (14 patients, including 4 with gross hematuria). The glomerular diseases found on biopsy were IgA nephropathy (n = 5 patients), focal segmental glomerulosclerosis (n = 4), membranoproliferative glomerulonephritis (n = 2), acute postinfectious glomerulonephritis (n = 2), pauci-immune crescentic glomerulonephritis (n = 2), membranous glomerulonephritis (n = 1), and lupus nephritis (n = 1). Follow-up (mean, 47 months; range, 2-141 months) was available on 16 patients (94%). Two patients (1 with membranous glomerulonephritis and 1 with acute postinfectious glomerulonephritis) had complete remission; 8 patients (4 with IgA nephropathy, 2 with focal segmental glomerulosclerosis, 1 with lupus nephritis, and 1 with acute postinfectious glomerulonephritis) had chronic kidney disease; and 6 patients (2 with pauci-immune crescentic glomerulonephritis, 2 with membranoproliferative glomerulonephritis, 1 with IgA nephropathy, and 1 with focal segmental glomerulosclerosis) progressed to end-stage renal disease, 4 of whom died. In summary, a wide spectrum of glomerular diseases can be seen in patients with Down syndrome, with IgA nephropathy and focal segmental glomerulosclerosis being the most common. Renal biopsy is necessary to determine the type of glomerular lesion and appropriate treatment.     

PROTO-ONCOGENE EXPRESSION IN HUMAN GLOMERULAR DISEASES

The expression of the protein products and mRNA of c- fos , c- myc , p53, and c- raf was examined in normal renal tissues and biopsy specimens from 73 patients with various glomerular diseases. Immunofluorescent staining showed that there were cell nuclei stained for c-Fos, c-Myc, and p53, and cytoplasm positive for c-Raf, in the glomeruli of patients with proliferative types of glomerulonephritis, including IgA nephritis and lupus nephritis, and in patients with focal glomerular sclerosis. Glomerular expression of c- fos and c- myc mRNA was detected by in situ hybridization. The number of proto-oncogene-positive glomerular cells was significantly higher in lupus nephritis, IgA nephritis, and focal segmental sclerosis, as compared with minimal change nephrotic syndrome and normal specimens. In IgA nephritis, the population of glomerular cells positive for c-Fos and c-Myc and the grade of c-Raf immunoreactivity were significantly correlated with the proportion of proliferating cell nuclear antigen (PCNA)-positive glomerular cells, with histological grading of mesangial hypercellularity and matrix increase, and with the magnitude of proteinuria. These data indicate that proto-oncogene expression is associated with mesangial proliferation and matrix expansion in proliferative types of glomerulonephritis and in focal glomerular sclerosis.     

Rapid Diagnosis of Extrapulmonary Tuberculosis by Ligase Chain Reaction Amplification

A rapid amplification-based test for the diagnosis of extrapulmonary tuberculosis, the LCx Mycobacterium tuberculosis Assay from Abbott Laboratories, was evaluated. Results from the LCx M. tuberculosis Assay were compared with those from culture and the final clinical diagnosis for each patient. A total of 526 nonrespiratory specimens from 492 patients were tested. The specimens included urine; feces; lymph node exudates; pleural, cerebrospinal, articular, and ascitic fluids; tissue biopsies; gastric aspirates; purulent exudates; blood; and bone marrow aspirates. After combination of the culture results and the patient’s clinical data, a total of 135 specimens were collected from 122 patients with a diagnosis of extrapulmonary tuberculosis. The sensitivity, specificity, and positive and negative predictive values for the LCx M. tuberculosis Assay were 77.7, 98.7, 95.2, and 93.1%, respectively; these values rose in resolved cases of TB to 78.5, 100, 100, and 93.1%, respectively. For 37 (27.4%) specimens from patients smear positive for the disease and 98 (72.6%) specimens from patients smear negative for the disease, the sensitivities of the LCx M. tuberculosis Assay were 100 and 71.1%, respectively. Statistically significant differences (P < 0.01) in sensitivities were found between culture and the LCx M. tuberculosis Assay. These differences were even greater among smear-negative specimens. The results demonstrate that the LCx M. tuberculosis Assay will provide rapid and valuable information for the diagnosis of extrapulmonary tuberculosis.     

Glomerular lesions in benign essential hypertension. A study of eight biopsy specimens with laboratory evidence suggestive of glomerular abnormalities

We performed renal biopsies on eight patients who had benign essential hypertension but laboratory abnormalities suggestive of glomerulonephritis. Persistent microscopic hematuria was detected in four patients, proteinuria in five, RBC casts in two, and decreased glomerular filtration in seven. In all eight biopsy specimens, we detected hyaline arterionephrosclerosis, focal glomerular obsolescence, and segmental, afibrillar thickening of glomerular basement membranes. Direct immunofluorescence studies performed on all eight samples were negative for immunoglobulins, complement, and fibrinogen. Although the patients in our study had laboratory findings suggestive of glomerulonephritis, the morphologic changes were indicative of benign essential hypertension.     

Comparison of dysmorphic erythrocytes with other urinary sediment parameters of renal bleeding

Dysmorphic erythrocytes have been described in the urine sediment of patients with renal parenchymal bleeding. This study compares the prevalence of dysmorphic erythrocytes in 5,128 urine specimens with blood, erythrocytic, or fibrin casts, proteinuria, and significant numbers of exfoliated renal tubular cells (RTCs). Of the 510 samples containing pathologic casts, 15% had dysmorphic erythrocytes, 60% had proteinuria, 71% had RTCs, and 12% had no other urinalysis abnormality. Of the 186 samples containing dysmorphic erythrocytes, 55% had pathologic casts, 42% had proteinuria, 71% had RTCs, and 13% had no other abnormality. Renal hematuria can best be evaluated by examination of all four of these urinalysis abnormalities rather than using a single entity for diagnosis. Patients with urinalysis evidence of renal hematuria should be evaluated further for renal disease rather than lower urinary tract disorders.     

A case of endocapillary proliferative glomerulonephritis with macrophages phagocytosing monoclonal immunoglobulin lambda light chain

Multiple myeloma (MM) is a plasma‐cell neoplasm that can cause renal disorders. Renal lesions in MM can present with a very rare pathological manifestation involving a specific monoclonal immunoglobulin (Ig). We report the case of a 33‐year‐old woman who had edema, fatigue, elevated serum creatinine levels, hypoalbuminemia, and hypercholesterolemia. She had persistent hematuria and proteinuria lasting 3 years. Serum protein electrophoresis showed an M‐spike, and serum immunofixation demonstrated the presence of monoclonal IgG λ. She had proteinuria in the nephrotic range, and a monoclonal λ fragment was present on urine immunofixation. Renal biopsy showed proliferative glomerulonephritis with λ light chain and C3c deposition and inflammatory cell infiltration with CD68. Macrophage lysosomes contained λ light chains, suggesting their partial phagocytosis. She was diagnosed with symptomatic MM and was treated with bortezomib and dexamethasone and an autologous peripheral stem cell transplant conditioned with intravenous melphalan. She achieved a partial response with decreased serum monoclonal protein and improved renal function. This case may be categorized as a monoclonal gammopathy‐associated proliferative glomerulonephritis. The biopsy finding of partially phagocytosed Ig λ light chains by macrophages is very rare; this pathological condition is similar to crystal‐storing histiocytosis.     

IgA-IgG nephropathy: a clinicopathologic entity with slow evolution and favorable prognosis.

Renal biopsy specimens were obtained from nine patients with proteinuria and persistent macroscopic or microscopic hematuria. Histologic examination either disclosed no abnormality or showed moderate mesangial thickening and occasionally, evidence of focal segmental glomerulonephritis. Immunofluorescent studies revealed diffuse generalized mesangial deposits of IgA, IgG and betalc in all specimens. Fibrinogen deposits were present in the mesangial space in four specimens only, while IgM was uniformly absent. Serial sections of identical glomeruli allowed the localization of betalc within both IgA and IgG deposits. Ultrastructural studies of the renal biopsy specimens showed accumulation of electron-dense material in the subendothelial region of the capillary loops and the mesangium, with thickening of its matrix. Follow-up data indicated a generally good prognosis.     

Analysis of urinary mononuclear cells as markers of renal injury

The presence of macrophages(M phi) in the urine of patients with glomerulonephritis(GN) reflects the pathological events in the kidney, and we have discovered the following correlations between the M phi phenotype and the pattern of renal injury. 1) Urinary macrophage(M phi) counts increase in patients with proliferative GN, especially in the presence of active glomerular lesions(glomerular tuft necrosis, crescent, and endocapillary proliferation). In patients with hematuria, a combination of urinary M phi and T-lymphocyte counts can be used to differentiate proliferative GN from non-proliferative renal disease(hereditary nephropathy and idiopathic renal hematuria). 2) The urinary M phi of patients with active proliferative GN express Fc gamma RIII(CD16) regardless of the type of GN. 3) There are two types of urinary CD68+ cells, CD68+25F9- cells(infiltrating M phi) and CD68+25F9+ cells(mature M phi). The CD68+25F9- cell counts in the urine correlate well with the activity of proliferative GN, and the CD68+25F9+ cell counts in the urine correlate with the magnitude of non-selective proteinuria and with the subsequent decline of renal function. The CD68+25F9+ cell count increase in the urine of patients with focal segmental glomerular sclerosis, but their numbers are negligible in minimal change nephrotic syndrome. These findings indicate that analysis of the urinary M phi phenotype is a useful strategy for evaluating renal injury as a "risk-free renal biopsy".     

Bacterial Lymphadenitis at a Major Referral Hospital in France from 2008 to 2012

Lymph node enlargement is a common medical problem, and in a large number of patients, the causes of lymphadenopathy remain undiagnosed. We report a thorough microbiological analysis of 1,688 lymph node biopsy specimens collected in our bartonellosis reference center. We studied lymph node biopsy samples from patients with suspected regional infectious lymph node enlargement from January 2008 to December 2012. To evaluate a useful strategy for the diagnosis of infectious lymphadenitis, specimens were cultured and subjected to molecular assays. Histologic analysis was done when possible. A total of 642 (38%) biopsy specimens were infected with a bacterial agent, and quantitative PCR (qPCR) was significantly better than 16S rRNA gene PCR (rrs) for the detection of Bartonella henselae (P = 0.05), Mycobacterium tuberculosis (P = 0.05), and Mycobacterium avium (P = 0.007). Molecular assays were significantly better than bacterial cultures for the diagnosis of Francisella tularensis (P = 0.017) but were less effective for detecting M. tuberculosis (P = 0.004) and M. avium (P = 0.001). Histologic analysis was done for 412 lymph nodes, and 20% of these were compatible with an infectious lymphadenitis, whereas a neoplasm was found in 29% of these lymph nodes. M. tuberculosis was detected significantly more in female than in male patients (P = 0.01), and patients with cat scratch disease (CSD) were younger than patients with M. tuberculosis, Tropheryma whipplei, and F. tularensis. Negative rrs PCR does not exclude the diagnosis of infectious lymphadenitis. Histologic analysis of lymph node biopsy specimens is critical, as a diagnosis of infectious lymphadenitis does not preclude other concurrent diseases.     

Protein-coding housekeeping gene Rv2461c can be used as an amplification target in loop-mediated isothermal amplification assay for the detection of Mycobacterium tuberculosis in sputum samples

The study is to explore the potential of the conserved Rv2461c gene as a biomarker for Tuberculosis (TB) diagnosis. The conservation of the hypothetical genes was evaluated in this study using multiple sequence alignment and phylogenetic analysis. The conservation of Rv2461c coding gene was evaluated by polymerase chain reaction using six reference strains of M. tuberculosis complex (MTC), 156 M. tuberculosis clinical isolates, 25 species of non-tuberculosis mycobacteria (NTM), and 10 non-mycobacterial species. A total of 126 clinical sputum specimens were collected from patients with respiratory symptoms, including 79 specimens from suspected TB patients, and 47 specimens from patients with respiratory diseases other than TB. Genomic DNAs were extracted and subject to polymerase chain reaction for nucleic acid amplification test. In addition, we successfully developed loop-mediated isothermal amplification (LAMP) technology for rapid detection of M. tuberculosis in sputum specimens. The sensitivity and specificity of LAMP assay were evaluated for the detection of M. tuberculosis. Phylogenetic analysis of the clpP sequences revealed that the Mycobacterium strains were split into two major clusters: i) MTC; ii) NTM strains and M. leprae. During the evaluation of the conservation of Rv2461c coding gene, all MTC strains yielded positive results, and no false-positive results were observed in NTM or other bacterial species. LAMP analysis showed high sensitivity and specificity (84.8% and 95.7%, respectively) for the detection of M. tuberculosis from sputum. Our result indicated that Rv2461c coding gene was an efficient and promising alternative nucleic acid amplification test target for the detection of M. tuberculosis.     

Comparison of bronchial washing,brushing and biopsy for diagnosis of pulmonary tuberculosis

The diagnostic yields of bronchial washings, bronchial brushings and lung biopsy specimens were compared in 50 patients with positive Mycobacterium tuberculosis cultures. The number of positive results obtained with cultures of bronchial brushings was significantly higher than that with bronchial washings (p < 0.001). The histological study of biopsy lung material improved the rate of immediate or rapid diagnosis of tuberculosis (p<0.001).     

Mesangiopathic glomerulonephritis in Zuni (New Mexico) Indians

Zuni is a Pueblo Indian village having more than a sixfold greater incidence of nondiabetic end-stage renal disease than the rest of the United States. Renal biopsy specimens from 44 patients with nondiabetic renal disease were subdivided into two groups. In group 1, 21 patients with asymptomatic microscopic hematuria revealed a mild mesangiopathic glomerulonephritis in 18 cases. The predominantly staining immunoglobulin was IgM in ten specimens and IgA in eight specimens. In group 2, 23 patients with symptomatic renal disease presented with nephrotic range proteinuria (11), renal insufficiency (eight), and hypertension (four). A mesangiopathic glomerulonephritis was diagnosed in 16 cases, and in 11 was IgA predominant. Three cases of membranoproliferative glomerulonephritis occurred in group 2. Five cases revealed focal glomerulosclerosis without immune deposits (three in group 1 and two in group 2). More than half (57%) of the patients undergoing biopsy were related. Cases of symptomatic nondiabetic renal disease showed a significant tendency to cluster among the members of four families, suggesting a hereditary influence in the pathogenesis of immune-mediated glomerulonephritis in the Zuni.     

Proliferative glomerulonephritis with discrete deposition of monoclonal immunoglobulin γ1 CH2 heavy chain and κ light chain: A new variant of monoclonal immunoglobulin deposition disease

A 45‐year‐old man presented with moderate proteinuria and hematuria. A renal biopsy showed mesangial/endocapillary proliferative glomerulonephritis, linear deposition of monoclonal immunoglobulin γ1 C_H2 heavy chain along glomerular and tubular basement membranes (GBMs and TBMs), granular deposition of κ light chain within the mesangial area, and continuous linear deposits of finely granular electron‐dense materials along GBMs and TBMs. Dual immunostaining showed essentially discrete glomerular localization of γ1 C_H2 heavy chain and κ light chain. Monoclonal protein was not detected in urine and serum. A bone marrow aspiration showed no abnormalities. Steroid therapy led to the improvement of proteinuria and hematuria. We would classify this case as a new variant of monoclonal immunoglobulin deposition disease, light chain/heavy chain deposition disease. In contrast with light and heavy chain deposition disease, the remarkable characteristics of this variant are separate deposition of monoclonal heavy chain and light chain, deposition of largely deleted γ heavy chain lacking the C_H1 domain, and good response to steroid therapy.     

Renal Manifestations in 2007 Korean Patients with Beh?et's Disease

Purpose

Behçet''s disease (BD) theoretically affects all sizes and types of blood vessels and results in multi-organ involvement. However, renal BD has not been fully characterized, though the kidneys are histologically rich in blood vessels.

Materials and Methods

A total of 2007 patients who fulfilled the diagnostic criteria for BD were enrolled in this study. We reviewed the medical records and test results of the BD patients and used univariate and multivariate logistic regression analyses to determine the clinical significance of renal involvement in BD.

Results

Among the 2007 BD patients, we noted hematuria in 412 (20.5%) and proteinuria in 29 (1.4%). Univariate analysis showed that the BD patients with hematuria were predominantly female and older, had higher erythrocyte sedimentation rates (ESRs), and more frequently presented with genital ulcerations. BD patients with proteinuria had higher ESR levels compared to BD patients without proteinuria. In the multivariate analysis, age, sex, and ESR were found to be significantly associated with hematuria in BD patients, whereas only ESR was associated with proteinuria in BD patients. We also found that IgA nephropathy was the most common pathologic diagnosis in 12 renal BD patients who underwent renal biopsies.

Conclusion

We suggest that routine urinalysis and serum renal function tests be performed for the early detection of renal BD, especially in older female BD patients with recurrent hematuria, high ESR levels, and frequent genital ulcers, as well as in BD patients with proteinuria and high ESR levels.     

A case of membranoproliferative glomerulonephritis associated with a hydatidiform mole

We treated a 54-year-old woman who was suffering from membranoproliferative glomerulonephritis associated with a complete type of hydatidiform mole. The renal manifestations were proteinuria and hematuria. A renal biopsy, performed before gynecologic management, disclosed focal and segmental subendothelial deposits with a proliferation of the mesangial cell and showed irregularly thickened capillary loops by light and electronmicroscoy. Genralized edema, proteinuria and hematuria were completely recovered by suction and curettage of the hydatidiform mole with prophylactic chemotherapy. The clinical manifestation of earlier presented 3 cases have been the nephrotic syndrome. The common feature of them was a complete remission of the nephropathy after the removal of the hydatidiform mole. The relationship between the hydatidiform mole and glomerulonephritis remains unresolved at present. But we concluded that the hydatidiform mole might be a cause of glomerulonephritis in this case.     

MPO-ANCA positive rapidly progressive glomerulonephritis in a patient with rheumatoid arthritis during treatment with D-penicillamine]

We present here a case of MPO-ANCA positive rapidly progressive glomerulonephritis (RPGN) after 34 months of D-penicillamine (D-PC) therapy for rheumatoid arthritis (RA). A 27-year-old Japanese woman was diagnosed as having RA in June 1994 at our out-patient clinic. Oral D-PC administration was initiated at a dose of 100 mg per day in January 1995. In August 1997, proteinuria, hematuria, renal insufficiency, and anemia developed. D-PC was withdrawn promptly, and prednisolone 5 mg per day was started. The patient was admitted to our hospital in September. On admission, anti-neutrophil cytoplasmic antibody against mycloperoxidase (MPO-ANCA) was strongly positive in the serum. Renal biopsy showed glomerulonephritis with cellular crescent formation in 60% of the glomeruli observed. Immunofluorescence examinations revealed deposits of granular IgG, IgA, C 1 q, and C 3 in the mesangium. The patient was treated with steroid pulse therapy along with administration of anti-coagulation and anti-platelet agents under the diagnosis of MPO-ANCA positive D-PC-induced RPGN. The renal function was gradually recovered and MPO-ANCA disappeared. Since RPGN is potentially a fatal disease, frequent monitoring of renal function and discontinuation of D-PC are required. In case MPO-ANCA becomes positive, prompt and correct diagnosis of the renal disorder could lead to a good prognosis as in this case. The present case may provide some important immunological insights into medical procedures to treat D-PC-induced RPGN and MPO-ANCA related glomerulonephritis.     

Detection ofMycobacterium tuberculosis complex in clinical specimens by a commercial polymerase chain reaction kit

A total of 722 respiratory and 86 nonrespiratory specimens obtained from 456 patients were tested for detection ofMycobacterium tuberculosis complex by a commercial polymerase chain reaction (PCR) kit (Amplicor, Roche Diagnostic Systems) and the results compared with those of microscopy and culture (solid and radiometric media). Respiratory and nonrespiratory specimens were analysed separately. Of the respiratory specimens, 54 were positive forMycobacterium tuberculosis complex both in the PCR and in culture, five were positive in the PCR but negative in culture, and eight were positive in culture but negative in the PCR. Four cultures were positive for mycobacteria other thanMycobacterium tuberculosis; none of these gave a positive result in the commercial test. Resolution of discrepant results was performed by analysis of patients' clinical data. For respiratory specimens the sensitivity of the commercial test was 87.6%, the specificity 99.6%, the positive predictive value 96.6%, and the negative predictive value 98.7%. For nonrespiratory specimens the sensitivity was 60%, whereas the specificity ranged as high as 98.6%. For this group the positive predictive value was 85.7% and the negative predictive value 94.9%. When respiratory specimens are used, the commercial PCR test for detection ofMycobacterium tuberculosis complex, with its high sensitivity and specificity, is a good complementary diagnostic tool for rapid diagnosis of bronchopulmonary tuberculosis in a routine mycobacterial laboratory.     

Renal pathology in hematopoietic cell transplantation recipients.

Hematopoietic cell transplantation-associated renal injury may be related to a combination of factors including chemotherapy, radiation, infection, immunosuppressive agents, ischemia, and graft-versus-host disease. Renal biopsy specimens from hematopoietic cell transplant recipients at two institutions (Stanford University Medical Center and Oregon Health & Science University) were reviewed in correlation with clinical data. Fifteen cases were identified (post hematopoietic cell transplant time 0.7-14.5 years), including six with autologous hematopoietic cell transplant. Indications for renal biopsy included proteinuria (n=13; nephrotic range in 8), increased serum creatinine (n=10), or both (n=6). Many patients had multiple pathologic findings on renal biopsy. Membranous glomerulonephritis was the most common diagnosis (n=7), including two patients with autologous hematopoietic cell transplant and five with evidence of chronic graft-versus-host disease elsewhere. Four membranous glomerulonephritis patients achieved sustained remission with rituximab therapy. Other glomerular pathology included focal segmental glomerulosclerosis (n=1) and minimal change disease (n=1). Evidence of thrombotic microangiopathy was common (in isolation or combined with other pathology), as was acute tubular necrosis and tubulointerstitial nephritis. Of 14 patients with follow-up (2-64 months, mean 19 months), 6 had chronic renal insufficiency (serum creatinine >1.5 mg/dl), 2 had end stage renal disease, and 6 had essentially normal renal function. Our retrospective study shows that renal dysfunction in hematopoietic cell transplant recipients is often multifactorial, and biopsy may reveal treatable causes. Membranous glomerulonephritis is seen in autologous and allogeneic hematopoietic cell transplant recipients, and may respond to anti-B-cell therapy, which has implications regarding pathogenesis and relationship to graft-versus-host disease.