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D C Snover

Publications and source records attributed to D C Snover.

At least 55 records · Page 3Linked to original sources
PubMed1989

Sensitivity, specificity, and positive predictivity of the Hemoccult test in screening for colorectal cancers. The University of Minnesota's Colon Cancer Control Study.

Data are presented on the sensitivity, specificity, and positive predictivity of the Hemoccult test based on the experience of the Minnesota Colon Cancer Control Study, a randomized clinical trial to determine whether the use of the Hemoccult test can reduce mortality from colorectal cancer. Rehydrating the slides with a drop of water before processing resulted in an increase in positivity (2.4% to 9.8%), and sensitivity (80.8% to 92.2%) but a decrease in specificity (97.7% to 90.4%) and positive predictivity (5.6% to 2.2%). The effects of age and sex were also evaluated. The test was less specific for men than women (p = 0.03). Specificity was highest for those less than 60 yr of age and decreased with increasing age (p = 0.05). The positive predictivity increased with age from 1.6% for those under 60 yr to 3.6% for those over 70 yr (p = 0.0004).

Age Factors↗
PubMed1989

Liver transplantation in a patient with protoporphyria.

A 38-yr-old woman with liver disease due to protoporphyria underwent orthotopic liver transplantation. The resected liver was cirrhotic and contained a massive amount of protoporphyrin, with numerous birefringent pigment deposits. Transplantation was accomplished without difficulty following blood volume exchange to reduce the blood protoporphyrin level. Sequential biopsy specimens obtained through the 13th month after transplantation showed no accumulation of protoporphyrin pigment deposits in the new liver. Portal inflammation observed in the liver biopsy specimen at 6 mo after transplantation resolved spontaneously. Erythrocyte and serum protoporphyrin levels returned to values similar to those in the pretransplantation period when the patient had normal hepatic function; the fecal level was lower. Thus orthotopic liver transplantation can be successfully done in patients with protoporphyria who have severe liver disease. Prolonged follow-up is needed to determine the ultimate outcome, however, as the new liver remains susceptible to protoporphyrin-induced damage.

Adult↗
PubMed1989

Hereditary tyrosinemia type I (chronic form): pathologic findings in the liver.

Hereditary tyrosinemia type I presents with either acute hepatic failure in the neonatal period or later in infancy with progressive liver dysfunction secondary to cirrhosis. The inevitably fatal outcome in those children with the chronic form has been transformed with the advent of liver transplantation. Native livers from five children who received allografts were studied pathologically and compared with earlier hepatic biopsies in two of these patients that had been performed several years before transplantation. Our findings support the conclusion that a sequence of morphologic changes from the initial micronodular cirrhosis through an intermediate mixed cirrhotic pattern to macronodular cirrhosis occurs. The micronodular phase is transitory, over a period of only a few months, since mixed micronodular macronodular cirrhosis was already present in the livers of children who received transplants by 11 months of age. Focal hepatocellular dysplasia was present in one of the livers with mixed cirrhosis but was not identified in the other two cases. Macronodular cirrhosis accompanied two cases of hepatocellular carcinoma in this study. In order to preclude the latter complication, liver replacement is necessary before the age of 2 years.

Adolescent↗
PubMed1989

Venoocclusive lesions of the central veins and portal vein radicles secondary to intraarterial 5-fluoro-2'-deoxyuridine infusion.

Venoocclusive disease is characterized by the occurrence of occlusive lesions of the central and subhepatic veins, usually involving the liver in a diffuse fashion. We report a case showing venoocclusive lesions of the central veins and the portal vein radicles affecting only a portion of the left lobe of the liver following intraarterial 5-fluoro-2'-deoxyuridine therapy for metastatic adenocarcinoma of the colon. Possible mechanisms and the significance of venoocclusive lesions of portal vein radicles are discussed.

Aged↗
PubMed1989

Immunopathology of graft-versus-host disease in the upper gastrointestinal tract.

Class I and class II (HLA-DR, DP and DQ) MHC antigen expression and the phenotypic nature of the inflammatory infiltrate in gastric and duodenal biopsies in bone marrow transplantation patients with and without graft-versus-host disease were investigated. Increased expression of class I (P less than 0.016) and class II (HLA-DR, DP) antigens (P less than 0.002) was associated with GVHD. The epithelium in two GVHD-positive biopsies was HLA-DP-positive and HLA-DR-negative. None of the tissues expressed HLA-DQ. Association between MHC antigen expression and phenotype of infiltrating cell was then examined. The majority of GVHD biopsies showed an infiltrate composed of CD4+ cells and CD8+ cells. However, the two DP+, DR- biopsies were associated exclusively with CD8+ intraepithelial cells, suggesting sequential events in GVHD, with CD8+ cells infiltrating tissue first associated with HLA-DP expressions, followed by accumulation of CD4+ as well as CD8+ cells in association with expression of HLA-DR.

Adolescent↗
PubMed1989

Correlation of Fourier spectral shift-determined hepatic acoustic attenuation coefficients with liver biopsy findings.

We calculated hepatic acoustic attenuation coefficients (ACs) in 13 patients who had liver biopsies and in 3 normal subjects by means of Fourier spectral analysis of reflected ultrasound signals from increasing depths in the liver. The ACs were correlated with estimated percentage area occupied by fat in the liver biopsies; linear regression analysis revealed a correlation coefficient of r = .78 (p less than .001). The presence of fibrosis did not correlate with AC.

Biopsy, Needle↗
PubMed1989

Problems in the interpretation of liver biopsies after liver transplantation.

As more liver transplants are performed and we realize that biopsy is the best means to diagnose rejection, the surgical pathologist has gained prominence as part of the transplant team. The surgical pathologist now plays a pivotal role in the day-to-day management of liver transplant patients. Diagnosis of rejection is a major task; however, other processes, particularly infectious ones, are also important causes of liver dysfunction that must be distinguished from rejection. Rapid and accurate diagnosis of acute rejection is possible if attention is paid to diagnostic criteria. The biopsy is also valuable to assess efficacy of therapy and provide prognostic information. The histological diagnosis of chronic rejection remains difficult, if not impossible. In all cases, and especially in the assessment of chronic rejection, close cooperation with the clinical staff is essential for proper patient management.

Acute Disease↗
PubMed1989

Significance of mucosal vs salivary gland changes in lip biopsies in the diagnosis of chronic graft-vs-host disease.

Lip biopsy is frequently utilized to diagnose and stage chronic graft-vs-host disease (cGVHD). However, the significance of mucosal (MU) vs salivary gland (SG) involvement as well as the minimal histologic changes necessary for diagnosis remain unclear. We evaluated 68 lip and oral mucosa biopsy specimens using published diagnostic criteria. Thirty-four specimens contained both MU and SG tissue. Both MU and SG were definitely involved in 13 patients while apparent false-negatives for MU of 20% (2/10) and SG of 11% (1/9) were observed. No clinical differences were noted among the patients with both MU-alone-, or SG-alone-positive biopsy specimens. Patients with no evidence of cGVHD in either MU or SG showed significantly less other organ involvement than patients with positive evidence. Patients with minimal MU changes (rare dyskeratotic cells) were clinically indistinguishable from negative patients in terms of other organ involvement. However, 50% of the biopsy specimens with minimal MU involvement in which SG were present had definite GVHD in the SG. These data indicate that lip biopsy specimens must include both MU and SG tissue to rule out oral GVHD. Minimal MU changes are insufficient to diagnose oral cGVHD, although they do warrant close follow-up and a second biopsy if SG tissue is not present in the specimen.

Adolescent↗
PubMed1988

Progressive CT appearance of hepatic metastases from colorectal carcinoma.

An 8-year retrospective review of 106 serial computed tomographic (CT) examinations performed on 32 patients with colorectal carcinoma metastatic to the liver was done to determine if the CT appearance of such metastases changed with a favorable response to chemotherapy or with progression of disease. Of these 32 patients, 15 underwent placement of an infusion pump for delivery of chemotherapy directly into the hepatic artery, 3 underwent partial hepatectomy, 1 underwent both procedures, and 13 underwent neither. Regression of hepatic metastases (7 patients), only seen following infusion pump placement, was associated with a decrease in size and an increase in margination of lesions. In two of these patients regression of metastases was seen in one area of the liver with subsequent progression or development of metastases in another region, presumably due to preferential delivery of chemotherapeutic agent. Progression of disease (23 patients) was associated with an increase in both size and number of lesions that became progressively less well marginated. Development of poorly marginated or infiltrative characteristics at the periphery of the lesion was associated with a poor prognosis. Thus, the CT characteristics of hepatic metastases from colorectal carcinoma differ with a favorable response to chemotherapy and with progression of disease.

Adenocarcinoma↗
PubMed1988

Acute rejection in human liver grafts: a comparative histologic study of cases maintained on azathioprine and prednisone versus cyclosporine A and low-dose steroids.

The morphology of acute rejection (AR) in biopsies of liver allografts obtained in the first 2 weeks after transplantation was analyzed. Material from patients maintained on azathioprine and prednisone (AZA; Groningen, The Netherlands) was compared with that of patients receiving cyclosporine A and prednisone (with or without azathioprine) in low doses (CSA; Minneapolis). Strict selection criteria were applied to exclude circulatory and biliary complications and viral infection in this early observation period after transplantation. Follow-up biopsies ranged from 3 weeks to 1 year after transplantation. Time zero biopsies and/or pretransplant biopsies served as baseline histology, Our data revealed an identical morphologic picture during AR early after transplantation in both patient groups, except for a more marked degree of venous endothelialitis and hepatocyte ballooning in the Minnesota material. The follow-up biopsies suggested a spontaneous resolution of these early rejection episodes without antirejection treatment in six of the ten AZA patients. No differences in the long-term survival rate between the CSA- and AZA-treated patients were observed.

Acute Disease↗
PubMed1988

Use of alpha-1-antitrypsin staining in the diagnosis of nodular regenerative hyperplasia of the liver.

Nodular regenerative hyperplasia (NRH) is a disorder characterized by regenerative nodules scattered diffusely throughout the liver without associated fibrosis. It is most often recognized at autopsy when the entire liver is available for inspection. The diagnosis of NRH by needle biopsy is much more subtle. Since alpha-1-antitrypsin (AAT) expression by hepatocytes in a variety of liver diseases has suggested that it may represent a marker for regenerative or damaged hepatocytes, we elected to study the expression of AAT by immunohistochemical staining of paraffin-embedded tissue of biopsy material as a possible marker of this diagnosis. Seventeen biopsies of the liver showing histologic features consistent with NRH were selected and compared with 20 biopsies of the liver without features of NRH. Eight of the NRH cases showed periportal granular AAT staining as opposed to only one of the non-NRH biopsies (P less than .01; Fisher exact test). These results indicate that AAT expression is increased in the regenerating compartment (as opposed to the presumably damaged atrophic portion) of the liver in NRH and suggest that AAT staining may be useful in confirming the biopsy diagnosis of NRH.

Adolescent↗
PubMed1988

Adenomas in glycogen storage disease type 1. Two cases with unusual histologic features.

Two cases of hepatic adenomas arising in patients with glycogen storage disease type I are presented. In both cases, the adenomas showed unusual histological features including marked fatty change, a polymorphonuclear infiltrate, Mallory hyalin, and lamellar fibrosis. In addition, one case was associated with amyloidosis. Such features have only recently been described in adenomas and have not been reported previously in association with glycogen storage disease type I.

Adult↗
PubMed1988

Diverticulitis in the multiple endocrine neoplasia type II B syndrome.

Diffuse ganglioneuromatosis of the entire alimentary tract is a characteristic finding in the multiple endocrine neoplasia type II B syndrome. Symptoms and complications of colonic involvement are common. We report a 37-yr-old woman with multiple endocrine neoplasia type II B syndrome and a colovesical fistula complicating sigmoid diverticulitis.

Adult↗
PubMed1987

Invasive Scopulariopsis in the immunocompromised host.

Opportunistic infections with fungal organisms have been well described in patients undergoing intensive chemotherapy and bone marrow transplantation. In two patients, invasive infections with the saprophyte Scopulariopsis developed either following intensive chemotherapy or bone marrow transplant. Fungal disease persisted in both patients despite resection of the primary focus and prolonged treatment with the usual antifungal agents, and contributed to the death of one patient.

Acute Disease↗