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M B Stokes

Publications and source records attributed to M B Stokes.

14 recordsLinked to original sources
PubMed2006

Immunofluorescence on pronase-digested paraffin sections: a valuable salvage technique for renal biopsies.

Direct immunofluorescence (IF) on frozen tissue is the method of choice for the study of medical renal diseases. When no glomeruli are available, IF can be performed on the formalin-fixed paraffin-embedded tissue allocated for light microscopy after antigen retrieval with proteases. In this study, the results of IF on frozen tissue (IF-F) and on deparaffinized, pronase-treated tissue (IF-P) were compared in 71 renal biopsies representing 12 major renal diseases. Using IF-P, diagnostic findings were obtained in 100% of cases of lupus nephritis, acute post-infectious glomerulonephritis, cryoglobulinemic glomerulonephritis, fibrillary glomerulonephritis, primary amyloidosis, myeloma cast nephropathy, and light-chain Fanconi syndrome (LCFS), 88% of cases of immunoglobulin (Ig)A nephropathy, 80% of cases of light-chain deposition disease, 60% of cases of membranoproliferative glomerulonephritis type 1, 50% of cases of idiopathic membranous glomerulopathy (MGN) and 20% of cases of anti-glomerular basement membrane (GBM) disease. IF-P was less sensitive than IF-F for the detection of C3 in all disease categories and for the detection of IgG in cases of MGN and anti-GBM disease. The diagnostic kappa light-chain staining was demonstrated in 100% of cases of LCFS by IF-P versus 40% by IF-F. We conclude that IF-P is a valuable salvage immunohistochemical technique for renal biopsies lacking adequate cortical sampling for IF-F, and is superior to IF-F for the diagnosis of LCFS.

Antigen-Antibody Complex↗
PubMed2006

Cellular focal segmental glomerulosclerosis: Clinical and pathologic features.

Five pathologic variants of idiopathic focal segmental glomerulosclerosis (FSGS) are recognized: collapsing (COLL), cellular (CELL), glomerular tip lesion (GTL), perihilar, and not otherwise specified (NOS). The prognostic significance of CELL FSGS has not been determined. We compared the presenting clinical and pathologic characteristics in 225 patients with CELL (N=22), COLL (N=56), GTL (N=60), and NOS (N=87) variants of idiopathic FSGS. CELL, COLL, and tip lesion all showed greater frequency and severity of nephrotic syndrome, and shorter time to biopsy compared to NOS. Predictors of end-stage renal disease (ESRD) for all FSGS patients included initial serum creatinine, % global sclerosis, % COLL lesions, chronic tubulo-interstitial injury score, and lack of remission response. COLL FSGS had the highest rate of renal insufficiency at presentation, most extensive glomerular involvement and chronic tubulo-interstitial disease, fewest remissions (13.2%), and highest rate of ESRD (65.3%). GTL patients were older and showed the highest remission rate (75.8%) and lowest rate of ESRD (5.7%). CELL variant showed intermediate rates of remission (44.5%) and ESRD (27.8%) compared to COLL and tip lesion. CELL variant may include cases of unsampled tip or COLL lesion, underscoring the importance of adequate sampling. Our data support the view that CELL and COLL FSGS are not equivalent and validates an approach to pathologic classification that distinguishes between COLL, CELL, and tip lesion variants of FSGS.

Adolescent↗
PubMed2002

Membranoproliferative glomerulonephritis associated with low-grade B cell lymphoma presenting in the kidney.

Low-grade B cell lymphoma of mucosa-associated tissue type (MALToma) rarely may involve the kidney. Membranoproliferative glomerulonephritis (MPGN) is an uncommon complication of B cell lymphoma and may be related to cryoglobulin and/or immunoglobulin synthesis by a secretory B cell clone. We report 2 patients with the novel renal biopsy findings of coexistent MALToma and MPGN. Both subjects presented with nephrotic proteinuria and renal insufficiency. One patient had a serum M protein (IgG K) but neither individual had any other clinical or serologic evidence of systemic disease, including hematolymphoid malignancy, autoimmune disease, cryoglobulinemia, or hepatitis C viral infection. Both renal biopsies demonstrated MPGN type I with immunoglobulin deposits that in 1 case showed light chain restriction (IgM K). Electron microscopy disclosed corresponding glomerular electron dense deposits in subendothelial locations. Both biopsies also contained atypical interstitial lymphoid infiltrates comprising marginal zone (centro-cyte-like) cells that infiltrated tubules and showed extra-capsular extension. Immunostains demonstrated a predominantly B cell population that lacked expression of CD5 and cycline D1, and gene rearrangement studies confirmed the presence of a monoclonal B cell population in both cases. These findings indicate that low-grade B cell lymphoma in the kidney may be an unexpected finding in patients with nephrotic syndrome related to MPGN. Immunophenotypic and gene rearrangement studies are important ancillary tools for the evaluation of atypical lymphoid infiltrates in kidney biopsies.

Aged↗
PubMed2001

Up-regulation of extracellular matrix proteoglycans and collagen type I in human crescentic glomerulonephritis.

BACKGROUND: The pathogenesis of crescentic glomerulonephritis (CGN) involves cellular migration and proliferation in the urinary space, frequently followed by fibrous organization. Extracellular matrix proteoglycans (PGs) may regulate these events via effects on cellular migration, interactions with growth factors, including transforming growth factor-beta (TGF-beta), and control of collagen fibrillogenesis. The expression of PG in human CGN is unknown. METHODS: Renal tissues from 18 patients with CGN were examined immunohistochemically for versican, decorin, biglycan and collagen type I, and were compared with morphologically normal tissues from six tumor nephrectomies. Synthesis of decorin, biglycan, and procollagen type I mRNAs was evaluated by in situ hybridization. RESULTS: Versican was strongly expressed in cellular crescents and periglomerular areas, whereas decorin and biglycan accumulated in collagen type I-enriched regions, including fibrocellular and fibrous crescents, and interstitial fibrosis. PG and collagen type I accumulation colocalized with myofibroblasts in crescents, periglomerular areas, and interstitium. CONCLUSIONS: The temporal and spatial patterns of expression demonstrated in this study provide evidence to support pathogenic roles for PG in the evolution of CGN. Based on known biological properties of this molecule, versican may facilitate migration of cells in developing crescents. Decorin and biglycan may contribute to progression of CGN, perhaps via interactions with collagen type I in the remodeled extracellular matrix.

Actins↗
PubMed2001

Necrotizing angiitis of the small intestine related to AA-amyloidosis: a novel association.

A 71-year-old man with intestinal pseudo-obstruction was found to have a diffusely thickened adynamic small bowel with AA-amyloid in submucosal vessels and muscularis propria, foreign body giant cell reaction to amyloid, and necrotizing angiitis. The mucosa was unremarkable. Immunostains demonstrated numerous CD68+ monocyte/macrophages and CD8+ T cells associated with the amyloid deposits. The patient had no evidence of systemic vasculitis and no underlying cause for AA-amyloidosis was identified. Necrotizing angiitis coexistent with amyloid angiopathy has been reported in brain and temporal arteries, but not in the gastrointestinal tract and not with AA-amyloid. The inflammatory cell infiltrates in this case are consistent with a foreign-body and/or cell-mediated immunologic reaction to AA-amyloid, although a role for these cells in amyloid formation cannot be excluded.

Aged↗
PubMed2000

Expression of decorin, biglycan, and collagen type I in human renal fibrosing disease.

BACKGROUND: The extracellular matrix proteoglycans decorin and biglycan may have a pathogenic role in renal fibrosing disease via regulation of the activity of growth factors, such as transforming growth factor-beta, and effects on collagen type I fibrillogenesis. The expression of decorin and biglycan in human glomerular diseases characterized by mesangial sclerosis is unknown. METHODS: Decorin, biglycan, and collagen type I were localized immunohistochemically in human renal biopsy cases of amyloidosis (N = 18), diabetic nephropathy (N = 11), fibrillary glomerulonephritis (N = 5), immunotactoid glomerulopathy (N = 5), light-chain deposition disease (N = 4), idiopathic mesangial sclerosis (N = 4), and nephrosclerosis (N = 6), and in morphologically normal tissues obtained from tumor nephrectomies (N = 8). Decorin and biglycan mRNA synthesis was evaluated by in situ hybridization. RESULTS: Decorin and biglycan protein were not identified in normal glomeruli. Decorin accumulated in amyloid deposits, but not in deposits of fibrillary glomerulonephritis or immunotactoid glomerulopathy. Biglycan weakly accumulated in amyloid deposits, and both decorin and biglycan weakly stained mesangial nodules in cases of morphologically advanced light-chain deposition disease and diabetic nephropathy. In all analyzed cases, irrespective of the underlying disease, decorin and biglycan accumulated in glomeruli in areas of fibrous organization of the urinary space and in areas of tubulointerstitial fibrosis. Biglycan, but not decorin, accumulated in the neointima of arteriosclerotic blood vessels. Decorin and biglycan mRNA synthesis was detected at sites of proteoglycan accumulation in glomeruli, interstitium, and neointima. Collagen type I colocalized with decorin and biglycan deposits. CONCLUSIONS: Differences in extracellular matrix proteoglycan composition may be diagnostically useful in distinguishing morphologically similar diseases. Distinct patterns of proteoglycan expression may be related to modulation of specific growth factor activity in different glomerular diseases.

Amyloidosis↗
PubMed1999

Collapsing glomerulopathy in renal allografts: a morphological pattern with diverse clinicopathologic associations.

We reviewed the clinical and pathological characteristics of seven patients with collapsing glomerulopathy (CG) in renal allograft biopsy specimens. All patients underwent biopsies for graft dysfunction. Two patients had nephrotic proteinuria (protein, >3.5 g/24 h), whereas all others had only modest or insignificant proteinuria. In five of seven patients, additional pathological processes, including microvascular injury, acute rejection, recurrent diabetic nephropathy, and immune complex glomerulonephritis, were present, each of which likely contributed to graft dysfunction and proteinuria. None of the patients in this series had nephrotic syndrome solely attributable to CG. Three biopsy specimens had features consistent with chronic rejection. The development of CG in renal allograft biopsy specimens was associated with graft dysfunction and a high rate of graft loss. These findings emphasize the prognostic significance of CG in renal allografts and suggest that CG may result from diverse pathogenic mechanisms.

Adult↗
PubMed1998

Combined membranous nephropathy and IgA nephropathy.

IgA nephropathy (IgAN) and membranous nephropathy (MN) are both common renal biopsy findings that rarely have been described together in the same patient. The significance of this finding is not clear. We present the clinical and pathological data of four patients with combined MN-IgAN and discuss possible pathogenetic mechanisms. By definition, all cases showed immunodominant mesangial deposits of IgA (+/-C3) and subepithelial capillary wall deposits of IgG (+/-C3) by immunofluorescence microscopy, confirmed by electron microscopy. There were three men and one woman, whose ages ranged from 41 to 67 years (average, 51.7 years). All four presented with microscopic hematuria and proteinuria, three in the nephrotic range. Renal function was normal in three individuals, and one subject had mild renal insufficiency accompanied by long-standing hypertension. Two other patients had newly uncovered hypertension. Complement levels were normal in all subjects. One patient had a positive antinuclear antibody (ANA) test, but none had other serologic or clinical features diagnostic of lupus. None of the four individuals had any other predisposing factors for either MN or IgAN, including hepatitis B infection. All four patients had stable renal function at last determination (average follow-up, 24 months; range, 4 to 34 months), with markedly reduced proteinuria in three individuals and persistent heavy proteinuria in one. A review of the literature indicates that combined MN-IgAN is most often characterized by heavy proteinuria and stable renal function. Some cases may be related to hepatitis B infection, but in most instances the cause is unknown. The combination of these two pathological processes does not result in a particularly deleterious clinical outcome for patients.

Adult↗
PubMed1997

Immune complex glomerulonephritis in patients coinfected with human immunodeficiency virus and hepatitis C virus.

Human immunodeficiency virus-associated nephropathy (HIVAN), characterized by heavy proteinuria, rapidly progressive renal failure, "collapsing" glomerulopathy, and tubulointerstitial abnormalities, is the most common finding in HIV-infected patients undergoing a renal biopsy and predominantly affects blacks. We describe the clinical features and renal pathologic findings of 12 intravenous drug users (IVDUs) coinfected with HIV and hepatitis C virus (HCV) who were selected for renal biopsy because they presented with features different from typical HIVAN, including hypertension, microscopic hematuria, and cryoglobulinemia. There were seven black and five Hispanic patients. Eleven patients had immune complex glomerulonephritis (ICGN); one had glomerulosclerosis with immune complex deposits. Ten individuals had evidence of past hepatitis B viral infection, but none had persistent hepatitis B surface antigenemia. No other underlying cause for immune complex glomerulonephritis was identified. Renal biopsy showed membranoproliferative glomerulonephritis in five patients, mesangial proliferative glomerulonephritis in five, membranous nephropathy in one, and "collapsing" glomerulopathy with immune complex deposits in one. Hepatitis C virus RNA was detected by reverse transcription-polymerase chain reaction (RT-PCR) in the renal tissue and/or serum of nine of the 11 patients tested, and also in the renal biopsy tissue of four of eight patients with clinical and pathologic features of typical HIVAN without immunofluorescence evidence of immune complex deposits. One patient presented with renal failure, five patients developed end-stage renal disease (ESRD) requiring hemodialysis (mean time, 6.5 months), and six had stable renal function after a mean follow-up of 29.1 months (range, 2 to 72 months). Liver function abnormalities were present in seven of the 12 individuals, including four of the six patients who developed renal failure. These findings indicate that in some patients coinfected with HIV and HCV, the development of ICGN may dominate the clinical course of the disease. The occurrence of ICGN among black patients at risk for HIVAN may be related to the relatively high prevalence of HCV infection among IVDUs in this group.

AIDS-Associated Nephropathy↗
PubMed1997

Nodular pulmonary immunoglobulin light chain deposits with coexistent amyloid and nonamyloid features in an HIV-infected patient.

Isolated nodular pulmonary amyloidosis is a rare condition characterized by localized deposits of immunoglobulin (Ig) light chain amyloid. Nonamyloid nodular light chain deposits in lungs can occur in systemic light chain deposition disease. Both amyloid and nonamyloid light chain deposits have been described at separate sites in the same or different organs but rarely in lungs. We report the clinical, radiologic, and pathologic findings in a drug user infected with the human immunodeficiency virus who had multinodular pulmonary Ig light chain deposits consisting of both amyloid and nonamyloid granular morphologic features. The deposits, closely associated with numerous plasma cells, had a unique histochemical and ultrastructural profile, with intermixed Congo red-positive fibrillar amyloid and Congo red-negative granular nonamyloid components. Immunohistochemical and immunoelectron microscopic studies showed reactivity of both the fibrillar and granular deposits for kappa and lambda light chains but not heavy chains. There was no evidence of restricted clonality of local or bone marrow plasma cells, serum or urine monoclonal protein, or secondary causes of amyloidosis. The amyloid deposits (but not the nonamyloid deposits) were reactive with antibody to amyloid rho component. There was no staining for other types of amyloid, i.e., amyloid A or transthyretin. The relationship between pulmonary amyloidosis, infection with the human immunodeficiency virus, and illicit drug use is unknown. We conclude that the nodular pulmonary light chain deposits with both amyloid and nonamyloid morphologic features are related to local plasma cell proliferation and that the fibrillar and nonfibrillar components most likely result from different conformations of the Ig light chains.

Adult↗
PubMedDate not supplied

Pancreatic endocrine tumor with signet ring cell features: a case report with novel ultrastructural observations.

The case of a malignant pancreatic endocrine neoplasm with an unusual signet ring cell appearance is reported. The tumor was resected from a 30-year-old man with a 4.0-cm tumor in the body of the pancreas diagnosed by computerized tomographic (CT) scan. The resected tumor had a unique morphology characterized by numerous mucin-negative, signet ring cells, which were argyrophilic and immunoreactive for cytokeratin (CAM 5.2), chromogranin, synaptophysin, neuron specific enolase, and gastrin. Dense-core neurosecretory-type granules and numerous cytoplasmic lamellar inclusions were identified by electron microscopy. These inclusion bodies consisted of multilayered concentric osmiophilic lamellae (myelin figures), which most likely represent an abnormal accumulation of degenerating organelles. Two years later, the patient developed an abdominal recurrence of the tumor, confirming its malignant behavior. This case expands the spectrum of pancreatic endocrine tumors to include an aggressive signet ring cell tumor with a novel ultrastructural basis.

Abdominal Neoplasms↗