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Biomedical subjects

G N Gephardt

Publications and source records attributed to G N Gephardt.

At least 37 records · Page 2Linked to original sources

Diffuse panbronchiolitis preceding ulcerative colitis.

To expand the clinical spectrum of ulcerative colitis-associated lung disease, we describe a patient with panbronchiolitis associated with ulcerative colitis. In addition to his having a distinctive pulmonary manifestation of this bowel disease, other noteworthy aspects of this patient's course include the onset of pulmonary symptoms several years prior to bowel manifestations and the partial resolution of his pulmonary symptoms following colectomy.

Adult↗

Transbronchial needle aspiration for histology specimens.

Fine-gauge (22-G) transbronchial needle aspiration (TBNA) has significantly added to the diagnostic yield of FOB, and in some institutions has become routine in staging bronchogenic carcinoma. Cytologic examination of the specimen obtained by n228G TBNA, however, has several limitations. The mediastinal aspirate can be contaminated by tumor cells from respiratory secretions, giving false positive diagnoses of unresectability. The diagnosis of benign conditions can seldom be made. Using 18-G TBNA, we can obtain specimens for histologic examination from paratracheal, peribronchial, and carinal areas by FOB. Both 18-G and 22-G TBNA were performed in 34 patients with radiographic abnormalities involving mediastinal or hilar areas. Tissue for histologic examination was obtained in 17 patients (50 percent) using 18-G TBNA and was diagnostic in 11 (32 percent), including three patients with benign conditions. The overall diagnostic yeild of 18-G TBNA was 41 percent (14/34 patients), increasing the yield of FOB from 50 percent to 58 percent. There were no false positive results and few minor complications. 18-G TBNA is effective in obtaining tissue for histologic examination and diagnosing benign conditions. In selected cases this technique increases the diagnostic yield of FOB.

Adenocarcinoma↗

Atheroembolic renal disease: association with renal arterial stenosis.

In elderly patients with generalized atherosclerosis and longstanding hypertension, progressive renal insufficiency should suggest renal artery occlusive disease and/or renal cholesterol embolization. Renal cholesterol embolization is not an absolute contraindication to successful surgical revascularization. Renal cholesterol emboli were identified in biopsy specimens obtained in 24 cases at the Cleveland Clinic from 1978 to 1986, and renal artery stenosis was an associated finding in 19. Clinical manifestations of generalized atherosclerosis were common, including ileofemoral atherosclerosis (18), coronary artery disease (16), carotid occlusive disease (15), and carotid occlusive disease with a history of stroke (8). Evidence of embolic events in other organs was common. Hypertension worsened before biopsy in 21 patients with and without renal artery stenosis. Surgery or angiography definitely or probably contributed to renal failure in 16. Of 12 who underwent surgical revascularization of a renal artery, renal function improved in five, remained stable in five, and worsened in one. Renal function improved in the three patients undergoing dialysis before revascularization, and two were able to discontinue dialysis.

Aged↗

Peripheral small cell undifferentiated carcinoma of the lung. Clinicopathologic features of 17 cases.

Seventeen cases of resectable peripheral small cell undifferentiated carcinoma of the lung were studied (average size, 2.1 cm; range, 0.9-3.5 cm). The carcinomas exhibited predominantly mixed intermediate and fusiform/spindle subtypes; in seven carcinomas there were at least some foci of oat cell subtype. There was no histologic evidence of typical carcinoid tumor. Seven cases were fixed in solutions appropriate for immunohistologic study; these exhibited prominent neuron-specific enolase activity but less prominent and more variable staining for the carcinoembryonic antigen and cytokeratins. All 17 cases were deemed resectable and had no clinical or radiologic evidence of metastasis. Seven (41%) patients died with recurrent and/or metastatic carcinoma (average survival, 1.7 years); five of these patients had carcinomas with at least some foci of oat cell foci subtype.

Adult↗

Nephrotic range proteinuria with "minimal change glomerulopathy" in human renal allografts: report of four cases.

Four patients who received renal allografts developed nephrotic range proteinuria 2 to 16 months after renal transplantation. Twenty-four-hour urine protein excretion at the time of renal allograft biopsy ranged from 5.9 to 17.0 g/24 hours. The serum creatinine at the time of renal allograft biopsy ranged from 2.0 to 3.9 mg/dl (180 to 350 mumol/L). Biopsies of the allografts demonstrated minimal glomerular abnormalities by light microscopy, immunomicroscopy, and electron microscopy. Two biopsies exhibited severe interstitial fibrosis. These four cases illustrate the unusual finding of "minimal change glomerulopathy" in renal allograft recipients exhibiting nephrotic range proteinuria. All four patients progressed to dialysis 4, 36, 46, and 53 months after transplantation. Transplant nephrectomy was performed in three patients. One showed acute cortical necrosis. Two showed glomerular, vascular, and tubular-interstitial features of chronic rejection.

Adult↗

Chronic glomerular microangiopathy complicating metastatic carcinoma.

Six cases of metastatic carcinoma associated with chronic glomerular microangiopathy and renal failure are reported. All had prominent subendothelial lucent zones and double-contoured glomerular basement membranes. There was no immunohistologic or ultrastructural evidence for immune complex entrapment in glomeruli. By immunohistology, material antigenically related to fibrin or fibrinogen was identified in glomerular basement membranes despite a paucity of typical fibrillar fibrin. Four patients received mitomycin C before the onset of renal disease, and one patient received chemotherapy other than mitomycin C before development of renal failure. One patient had no chemotherapy but was given radiotherapy, which did not include the kidneys in the irradiated field. These six cases emphasize the diverse pathophysiologic mechanisms by which glomerular microangiopathy may arise in metastatic carcinoma.

Adenocarcinoma↗

Pulmonary lymphoid neoplasms. Role of immunohistology in the study of cellular immunotypes and in differential diagnosis.

Seven cases of lymphoid neoplasms presenting in the lung were evaluated by immunohistology for T and B cell antigens and immunoglobulin light chains in frozen tissue sections. Although follow-up was short or inconclusive in some patients with lymphoma and pseudolymphoma, it was concluded that evaluation of T and B cell antigens and immunoglobulin light chains in frozen tissue is helpful in classifying lymphocytic neoplasms, especially in cases without definite cytologic evidence of malignancy. As demonstrated in two additional cases, lymphocyte/leukocyte markers in paraffin-embedded tissue are important in the differential diagnosis of lesions with cytologic features of malignancy.

Adult↗

Focal and segmental glomerulosclerosis. Immunohistologic study of 20 renal biopsy specimens.

To evaluate the deposition of immunoglobulins and complement and their relationship to sclerotic and nonsclerotic glomerular segments, immunoperoxidase without periodic acid-Schiff counterstain (IMP) and with periodic acid-Schiff counterstain (IMPAS) for IgG, IgA, IgM, and C3 was performed on cryostat-frozen sections using the direct method, along with routine light microscopy and electron microscopy, in a series of 20 renal biopsy specimens from 20 patients with the final diagnosis of focal and segmental glomerulosclerosis. Neither diffuse mesangial nor diffuse glomerular basement membrane deposits were detected by IMP, IMPAS, or electron microscopy. In 18 biopsy specimens, IMPAS demonstrated focal and segmental granular to globular deposits of IgM and/or C3 in sclerotic glomerular segments. In eight biopsy specimens, small granular deposits of IgM and/or C3 deposits were identified in optically normal glomeruli, suggesting that these deposits may precede segmental sclerosis.

Adolescent↗

Pulmonary vasculitis (Wegener's granulomatosis). Immunohistochemical study of T and B cell markers.

A case of pulmonary vasculitis (Wegener's granulomatosis) is reported in which immunoperoxidase studies demonstrated that the vascular lymphoid infiltrates were composed predominantly of T cells and monocytes. Occasional T cells, B cells and monocytes were identified in the alveolar septa. IgG, IgA, IgM, and C3 were not identified in pulmonary vessels, septa, or alveoli. These findings suggest that cellular rather than humoral-immune mechanisms predominate in pulmonary vasculitis.

B-Lymphocytes↗

Membranous glomerulopathy associated with captopril therapy.

Two cases of nephrotic syndrome and biopsy-proved membranous glomerulopathy (membranous glomerulonephritis) were encountered during captopril treatment of 53 hypertensive subjects in our institution. Both patients had impaired renal function before treatment and were treated with 600 mg per day. Discontinuation of captopril led to transient partial remission of proteinuria but was followed by a recurrent, fluctuating course over one year later. Repeat biopsies, eight and 12 months after discontinuation of the drug, demonstrated persistent subepithelial deposits in the glomerular basement membrane. There has been a decline in glomerular filtration rate since discontinuation of the drug, apparently due to arterionephrosclerosis. These studies suggest that glomerular basement membrane deposits in captopril-associated membranous glomerulonephritis are not readily reversible and may be associated with persistent proteinuria, contrary to some previous reports.

Basement Membrane↗

Membranous glomerulonephritis associated with industrial mercury exposure. Study of pathogenetic mechanisms.

The nephrotoxicity associated with mercury may be manifested as either acute tubular necrosis or an immune complex glomerulonephritis, depending upon the conditions under which the patient is exposed to the metal. Two patients with industrial exposure to mercury developed the nephrotic syndrome due to membranous glomerulonephritis. A multidisciplinary approach was used to define more precisely the pathogenetic mechanisms involved in the production of the glomerular lesion. Although glomeruli were normal by light microscopy, immunohistochemical studies demonstrated confluent finely granular epimembranous deposits of IgG and C3. This distribution was confirmed at the ultrastructural level with immunoelectron microscopy. High resolution elemental analysis of electron dense inclusions in tubular epithelial phagolysosomes demonstrated energy dispersion spectra characteristic of coexisting mercury and selenium. Eluates from the biopsy material were not immunoreactive against normal rat or human kidney. There was no immunoreactivity of epimembranous deposits with antibodies having renal tubular epithelial antigen or urinary uromucoid specificity. These observations suggest that a distinctive immunopathologic lesion is associated with mercury-associated membraneous glomerulonephritis, that the role of the metal itself may only be coincidental, and that the involved antigen remains unknown. Prednisone therapy had no documented persistent beneficial influence upon the level of proteinuria in one patient who has been lost to follow-up. In one patient not treated with steroid therapy, withdrawal of exposure to the metal resulted in disappearance of mercury from body fluids and clinical remission.

Adult↗

Light chain nephropathy.

In 13 specimens of renal tissue from 11 patients, deposits of monoclonal immunoglobulin light chains and continuous granular electron-dense material within tubular basement membranes and in association with the glomerular basement membrane were identified. All but one patient were men n the fifth to seventh decades of life, and each presented with azotemia and features of glomerular rather than tubulointerstitial disease. Osteolytic bone lesions occurred in only three patients, and a bone marrow plasmacytosis greater than 30 percent consistent with plasma cell myeloma was identified in only four patients. Light chain distribution in the nephron was confirmed with immunoelectron microscopy and was not associated with deposition of other serum proteins such as immunoglobulin heavy chains, complement, transferrin, alpha 2 macroglobulin and albumin. The electron dense deposits differed in distribution and character from those associated with membranoproliferative glomerulonephritis type II (dense deposit disease), amyloidosis, cryoglobulinemia, macroglobulinemia and benign monoclonal gammopathy. Serum from six of these patients did not bind to normal human or rat renal parenchyma in vitro. Kappa light chain nephropathy was characterized by predominant linear tubular basement membrane kappa deposits, and nodular mesangial and linear glomerular basement membrane kappa immunostaining. Lambda light chain nephropathy was characterized by linear lambda glomerular basement membrane and tubular basement membrane immunostaining. Manifestations of glomerular dysfunction dominated the clinical presentation of light chain nephropathy, and most patients did not have typical features of multiple myeloma. The diagnosis was predicated upon thorough immmunohistologic assessment of renal biopsy material.

Adult↗