PubMed Health⌕ Search

Biomedical subjects

S S Iskandar

Publications and source records attributed to S S Iskandar.

At least 19 recordsLinked to original sources
PubMed2001

Non-diabetic nodular glomerulosclerosis associated with p-ANCA seropositivity: a case report and review of the literature.

A 73-year-old white man with slowly progressive chronic renal failure and nephrotic-range proteinuria was found to have antineutrophil cytoplasmic antibody in a perinuclear pattern (p-ANCA) at a titer of 1:800. Renal histologic findings revealed an advanced scarring glomerulopathy with diffuse and nodular mesangial sclerosis. Light, electron, and immunofluorescence microscopic findings were highly suggestive of diabetic glomerulosclerosis. Interestingly, this patient had no history of diabetes mellitus or diabetic retinopathy. The presence of p-ANCA positivity can be found in patients with a broad range of renal histologic findings, and does not necessarily imply the existence of pauci-immune necrotizing crescentic glomerulonephritis. For this reason, we urge caution in the empiric cytotoxic treatment of p-ANCA-associated renal disease in stable patients. When possible, a tissue diagnosis should be made.

Aged↗
PubMed2000

IgA nephropathy and Reiter's syndrome. Report of two cases and review of the literature.

Immunoglobulin A (IgA) nephropathy is the commonest type of primary glomerulonephritis worldwide. It has previously been reported in association with the seronegative spondyloarthropathies (ankylosing spondylitis, Behcet's syndrome, psoriatic arthritis, Reiter's syndrome and the postenteritic arthritides). Since this condition was first described in 1968, 5 previous case reports of biopsy-proven IgA nephropathy associated with Reiter's syndrome have been published in the English-language literature. Here we report 2 more such cases, along with a review of the literature describing the association of IgA nephropathy and a number of other immune-complex-mediated glomerulonephritides with the seronegative spondyloarthropathies.

Adult↗
PubMed2000

Lobular carcinoma of the breast metastatic to the oral cavity mimicking polymorphous low-grade adenocarcinoma of the minor salivary glands.

The oral cavity is a rare site of metastatic lesions; however, metastatic breast carcinoma must be included in the differential diagnosis of tumors of that site in women. We describe a 54-year-old woman who presented with a lesion of the floor of the mouth that histologically resembled polymorphous low-grade adenocarcinoma of the minor salivary glands, which was eventually established to represent metastatic lobular breast carcinoma. The final diagnosis was based on comparison with a primary tumor resected 13 years earlier and immunohistochemical reactivity with antibodies to steroid receptors. Relevant aspects of lobular breast carcinoma, polymorphous low-grade adenocarcinoma, and metastatic oral cavity lesions are discussed.

Adenocarcinoma↗
PubMed1999

Biopsy-proven resolution of immune complex-mediated crescentic glomerulonephritis with mycophenolate mofetil therapy in an allograft.

We report biopsy-proven resolution of immune-complex-mediated crescentic glomerulonephritis (ICMCGn) using mycophenolate mofetil (MMF). Therapy with steroids and cyclophosphamide failed twice in a 39-year-old white man who developed ICMCGn in his native kidneys, and subsequently in a human lymphocyte antigen-identical renal allograft. When he developed ICMCGn in a second, now cadaver, allograft, he was treated with steroids and MMF instead. His serum creatinine (Cr) improved from 4.4 mg/dL to 2.1 mg/dL. A biopsy 21 months later showed him to be free of glomerular disease. MMF is known to be an effective immunosuppressant. In our patient, ICMCGn, a notoriously difficult entity to treat effectively, seemingly resolved with MMF therapy. We suggest that MMF may be effective in the treatment of immunologically mediated pre-end-stage renal disease (ESRD). It should be considered in any posttransplantation setting where the original cause of organ failure is known to be immunologically mediated and likely to recur.

Adult↗
PubMed1996

Intravascular papillary endothelial hyperplasia in a thrombosed renal allograft vein.

Intravascular papillary endothelial hyperplasia (IPEH) is a benign endothelial proliferation of unclear pathogenesis, usually associated with thrombus as an unusual mode of organization and occasionally coexisting with vascular neoplasms. A 65-year-old white woman with chronic renal disease caused by focal segmental glomerulosclerosis experienced the failure of a cadaveric renal allograft 10 days after implantation. Pathological manifestations in the resected graft included total infarction and thrombi in both the renal artery and vein, the latter of which showed typical histopathologic features of IPEH. Papillary formations with fibrinous cores lined by bland endothelial cells surrounded fresh and organizing thrombus, and the proliferation had a highly cellular peripheral zone not readily recognizable as vascular. Immunohistochemical stains for factor VIII, CD34, and in particular CD31, however, confirmed the nature of both the papillary and solid areas of the proliferation as vascular endothelium. We present the first report of this lesion in an allograft vessel, and we find its rapid development, in association with a thrombus of clinically discernable age, to be strong evidence supporting the hypothesis that IPEH represents an uncommon morphology of organizing thrombus.

Aged↗
PubMed1996

Immunocytochemical localization of renin in the developing ovine fetus.

The ontogeny of renin distribution in the outer cortical segments was studied by immunocytochemistry in two groups of ovine fetal kidneys; one set of fetal kidneys was obtained at 104-106 days (0.73 gestation, n = 6), and the other at 138-140 days (0.96 gestation, n = 6). Similar studies were performed in kidneys obtained from a lamb (2 weeks old) and from non-pregnant adult sheep, n = 4. Using rabbit anti-mouse renin antiserum that was proven to cross react with sheep renin and 0.033% 3',3'-diamino benzidine tetrachloride as a chromogen, immunoreactivity was found to be localized in the classical juxtaglomerular apparatus and the afferent arteriole in the immature fetuses, newborn lamb and adult sheep. In the mature fetuses a more extensive distribution was noted. Immunoreactivity was found in the afferent arteriole and the juxtaglomerular apparatus as well as other segments of the arterial vascular tree. These findings suggest that renal renin distribution in the lamb fetus is developmentally regulated. The results also correlate well with reports about renal cortical renin content and plasma renin activity at the stages studied. These observations further support the hypothesis that increased renal renin expression occurs in the fetus just prior to birth.

Animals↗
PubMed1995

The link between hypertension and nephrosclerosis.

Nephrosclerosis is literally defined as hardening of the kidneys (Greek derivation: nephros, kidney; sklerosis, hardening). It is the result of scarring or replacement of the normal renal parenchyma by dense collagenous tissue. In practice, nephrosclerosis refers to diseases with predominant pathologic changes occurring in the preglomerular microvasculature and secondarily involving the glomeruli and interstitium. The relationship between mild to moderate hypertension and either nephrosclerosis or end-stage renal disease (ESRD) remains circumstantial, although these syndromes have long been associated in the medical literature. Nephrologists credit hypertension as the etiology of nephrosclerosis in 25% of patients initiating Medicare-supported renal replacement therapy, even though other processes may cause similar renal pathologic findings. Strikingly, serum creatinine values infrequently increase in patients with long-standing mild to moderate hypertension. Patients classified as having hypertensive ESRD typically present with advanced disease, making the processes that initiated the renal disease difficult to detect. Nephrologists are twice as likely to label an African-American patient as having hypertensive nephrosclerosis, compared with a white patient, when presented with identical clinical histories. This review proposes that many patients classified as having hypertensive nephrosclerosis actually have intrinsic renal parenchymal diseases, renal artery stenosis, unrecognized episodes of accelerated hypertension, or a primary renal microvascular disease. The familial clustering of ESRD attributed to hypertension in African-Americans and the identification of genes associated with renal injury in animals support the concept that inherited factors may predispose to renal failure. African-American families often have members with ESRD from disparate etiologies, including hypertensive ESRD. This suggests that common mechanisms, be they inherited or environmental, underlie the development of progressive renal failure in diverse forms of nephropathy. Identification of the mechanisms producing susceptibility to progressive renal disease would support the concept that mild to moderate elevations in blood pressure per se are uncommon causes of nephrosclerosis.

Animals↗
PubMed1995

Extra-adrenal myelolipoma: report of two cases.

Myelolipomas are benign tumors composed of an admixture of mature adipose tissue and normal hematopoietic cells. The vast majority occur within the adrenal glands, but several extra-adrenal myelolipomas (EAMLs) have been reported. The typical EAML is a solitary, well-defined mass within the abdomen, most commonly in the retroperitoneal presacral area. EAMLs may produce symptoms related to their mass effect, but they are occasionally incidental findings. Most commonly, the patient is older than 40 years and has no hematologic abnormalities. It is important to distinguish EAMLs from other soft tissue tumors, in particular liposarcomas, myxoid malignant fibrous histiocytomas, and extramedullary hematopoietic tumors. We discuss two cases of EAML. The first was in the retroperitoneum of a 76-year-old woman. It is the largest EAML ever reported, measuring 26 cm x 15 cm x 11 cm. The second, a presacral mass in a 68-year-old man, was diagnosed preoperatively by percutaneous computed tomography-guided fine needle aspiration biopsy. Preoperative diagnosis facilitated surgical management in this case. We discuss the clinical, radiologic, and pathologic characteristics and the differential diagnosis of this rare entity.

Aged↗
PubMed1993

Lipid-laden foamy macrophages in renal cell carcinoma. Potential frozen section diagnostic pitfall.

Lipid-laden foamy macrophages are characteristic of xanthogranulomatous pyelonephritis (XGP). We have encountered a case of renal cell carcinoma (RCC), with extensive necrosis, in which confluent sheets of foamy macrophages were a dominant feature. We describe the case and discuss the potential frozen section diagnostic problem in attempting to distinguish between confluent sheets of xanthoma cells a "reactive" change in RCC and xanthoma cells as a fundamental component of XGP. We propose that awareness of that problem should prompt the pathologist to request additional samples.

Aged↗
PubMed1992

Clinical and pathologic features of fibrillary glomerulonephritis.

A diagnosis of fibrillary glomerulonephritis was made in 31 renal biopsies from 28 patients on the basis of the electron microscopic identification of glomerular deposits of randomly arranged fibrils that resembled amyloidosis but were larger. This accounted for approximately 1% of all nontransplant renal biopsy diagnoses. Renal biopsy specimens with parallel arrays of 30 nm to 50 nm microtubules (that is, immunotactoid glomerulopathy) were not included in the study. The patients had a mean age of 49 years with a range of 21 to 75. The male to female ratio was 1:1.8 and the ratio of Whites to Blacks was 8.3:1, which differs from the 3:1 ratio in our overall biopsy population. All patients had proteinuria (mean 6.0 g/day), and most had hematuria and renal insufficiency. After a mean follow-up of 24 months, there was 48% renal survival. The light microscopic appearance of the fibrillary glomerulonephritis was quite varied. Capillary wall thickening and matrix expansion were the most frequent alterations. Nineteen percent of specimens had crescents. Morphometric ultrastructural analysis demonstrated a mean fibril diameter of 22.4 +/- 7.4 nm. Immunofluorescence microscopy revealed that IgG was the dominant and often the only immunoglobulin class in immune deposits, and subclass analysis revealed that IgG4 was the dominant or exclusive subclass in all specimens tested. We hypothesize that the relatively homogeneous nature of the immunoglobulin in the immune deposits is the basis for the fibril formation.

Adult↗
PubMed1991

C1q nephropathy: a pediatric clinicopathologic study.

We report on 15 children with proteinuria, at the nephrotic level in the majority of cases, who had no histologic glomerular alterations (eight cases), or focal and segmental glomerular scarring with (three cases) or without (four cases) mesangial proliferation. In all cases, immunofluorescence (IF) microscopy showed prominent mesangial C1q deposits with variable amounts of immunoglobulins. Ultrastructurally, most had conspicuous mesangial electron-dense deposits. Cases with no glomerular histologic alterations were histologically indistinguishable from minimal change disease (MCD), yet they uniformly had an unsatisfactory response to oral prednisone. Thus, the presence of immune deposits with a prominent C1q contribution identifies a group of cases that respond poorly to steroids and that, if light microscopy is considered in isolation, might otherwise be designated MCD.

Adolescent↗
PubMed1991

Targeted enzyme therapy of experimental glomerulonephritis in rats.

We sought to determine whether systemic administration of proteases ameliorates membranous nephritis induced in rats by immunization and challenge with cationic bovine gamma globulin, and whether targeting of protease to glomerular capillaries increases efficacy. Proteases substituted with biotin were targeted via the cationic protein avidin A, which by virtue of its charge has affinity for the glomerular basement membrane. Despite identical pretreatment proteinuria, rats given untargeted protease (biotin-conjugated without avidin, or unconjugated plus avidin) had significantly less proteinuria than saline-treated controls and nephrotic rats given avidin plus biotin-conjugated (targeted) protease had even less proteinuria and reduced glomerular rat IgG and C3. Among more severely nephrotic rats, targeted protease was again more effective than untargeted protease at reducing proteinuria, and also decreased the size of electron-dense glomerular deposits, hypercholesterolemia, and creatininemia. Inactivated targeted proteases had no effect on proteinuria, hypercholesterolemia, or azotemia. Finally, active targeted protease did not affect proteinuria in the nonimmune mediated nephrosis induced by puromycin aminonucleoside. We conclude that systemic protease can specifically diminish glomerular immune deposits, proteinuria, hyperlipidemia, and creatininemia associated with experimental immune complex glomerulonephritis but not toxic nephrosis, and that targeted protease is more effective than untargeted protease.

Albuminuria↗
PubMed1991

The effect of a high salt diet and gender on blood pressure, urinary protein excretion and renal pathology in SHR rats.

A high salt diet produced increases in SBP, urinary protein excretion (UPE) and renal vascular lesions (RVL) across groups of male and female SHR rats which were allowed to develop moderate or excessive increases in SBP. A highly significant linear relationship between SBP and log-transformed UPE was found when the data from all groups were analyzed together. Males developed high blood-pressure more rapidly, and exhibited more severe RVL and greater UPE than females. Two results prevent the conclusion that the elevated UPE was simply due to the adverse effects of high BP on the kidney. First, the relationship between SBP and UPE across groups could not be demonstrated when regression analyses were performed within individual dietary sub-groups. Secondly, gender differences in UPE were highly significant by analysis of covariance adjusting for individual differences in SBP. The increases in SBP and UPE may be independent consequences of ingestion of a high salt diet.

Animals↗