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Biomedical subjects

A J Lazenby

Publications and source records attributed to A J Lazenby.

At least 19 recordsLinked to original sources

Prospective endoscopic evaluation for gastrointestinal graft-versus-host disease: determination of the best diagnostic approach.

The best endoscopic diagnostic strategy for gastrointestinal (GI) graft-versus-host disease (GVHD) is unknown. Over a 48-month period, all patients with unexplained diarrhea at risk for acute gastrointestinal GVHD were prospectively identified. Acute GVHD was defined as symptoms and histologic evidence of GVHD occurring within 100 days of transplant or donor lymphocyte infusion (DLI). Colonoscopy was performed with multiple biopsies of the ileum, right colon and rectosigmoid colon. Next, upper endoscopy with duodenal and random gastric biopsies of both antrum and body were performed. All biopsies were evaluated for GVHD by an experienced GI pathologist. Over the study period, 24 patients (mean age 37 years; 62.5% male) were evaluated. The median time from transplantation or DLI was 30.5 days. The biopsy site with the highest yield was the distal colon (82%). A combination of upper endoscopy with sigmoidoscopy and colonoscopy with ileal biopsies were equivalent ( approximately 94%). In patients with diarrhea at risk for GVHD, biopsies of the distal colon had the highest diagnostic yield suggesting the importance of sigmoidoscopy and biopsy. Colonoscopy and ileoscopy or flexible sigmoidoscopy plus upper endoscopy had the highest diagnostic yields.

Adolescent↗

Reproducibility of the diagnosis of dysplasia in Barrett esophagus: a reaffirmation.

Morphologic assessment of dysplasia in Barrett esophagus, despite limitations, remains the basis of treatment. We rigorously tested modified 1988 criteria, assessing intraobserver and interobserver reproducibility. Participants submitted slides of Barrett mucosa negative (BE) and indefinite (IND) for dysplasia, with low-grade dysplasia (LGD) and high-grade dysplasia (HGD), and with carcinoma. Two hundred fifty slides were divided into 2 groups. The first 125 slides were reviewed, without knowledge of the prior diagnoses, on 2 occasions by 12 gastrointestinal pathologists without prior discussion of criteria. Results were analyzed by kappa statistics, which correct for agreement by chance. A consensus meeting was then held, establishing, by group review of the index 125 slides, the criteria outlined herein. The second 125-slide set was then reviewed twice by each of the same 12 pathologists, and follow-up kappa statistics were calculated. When statistical analysis was performed using 2 broad diagnostic categories (BE, IND, and LG v HG and carcinoma), intraobserver agreement was near perfect both before and after the consensus meeting (mean kappa = 0.82 and 0.80). Interobserver agreement was substantial (kappa = 0.66) and improved after the consensus meeting (kappa = 0.70; P =.02). When statistical analysis was performed using 4 clinically relevant separations (BE; IND and LGD; HGD; carcinoma), mean intraobserver kappa improved from 0.64 to 0.68 (both substantial) after the consensus meeting, and mean interobserver kappa improved from 0.43 to 0.46 (both moderate agreement). When statistical analysis was performed using 4 diagnostic categories that required distinction between LGD and IND (BE; IND; LGD; HGD and carcinoma), the pre-consensus meeting mean intraobserver kappa was 0.60 (substantial agreement), improving to 0.65 after the meeting (P <.05). Interobserver agreement was poorer, with premeeting and postmeeting mean values unchanged (kappa = 0.43 at both times). Interobserver agreement was substantial for HGD/carcinoma (kappa = 0.65), moderate to substantial for BE (kappa = 0.58), fair for LGD (kappa = 0.32), and slight for IND (kappa = 0.15). The intraobserver reproducibility for the diagnosis of dysplasia in BE was substantial. Interobserver reproducibility was substantial at the ends of the spectrum (BE and HG/carcinoma) but slight for IND. Both intraobserver and interobserver variation improved overall after the application of a modified grading system developed at a consensus conference but not in separation of BE, IND, and LGD. The criteria used by the group are presented. HUM PATHOL 32:368-978.

Algorithms↗

Dysplasia as a predictive marker for invasive carcinoma in Barrett esophagus: a follow-up study based on 138 cases from a diagnostic variability study.

The objective of endoscopic surveillance in Barrett esophagus (BE) is to assess the risk of subsequent development of invasive carcinoma. Criteria for morphologic evaluation of dysplasia, the presumed precursor lesion, have been established, although there are surprisingly few data in the literature correlating biopsy diagnosis of dysplasia with outcome. We collected follow-up information on 138 patients with BE whose initial endoscopic biopsy specimens had been selected for submission in an interobserver variability study performed by 12 pathologists with special interest in gastrointestinal pathology and reviewed blindly twice each by all the participants. Cases were scored as BE with no dysplasia, atypia indefinite for dysplasia (IND), low-grade dysplasia (LGD), high-grade dysplasia (HGD), intramucosal carcinoma, and frankly invasive carcinoma, thus generating 24 scores on each biopsy specimen. Clinical follow-up was obtained and correlated with both the submitting diagnoses and majority diagnoses. Kaplan-Meier statistics were used to compare both the submitting and majority diagnoses with outcome using detection or documentation of invasive carcinoma as the endpoint. Using the submitting diagnoses, no invasive carcinomas were detected in 44 cases diagnosed as BE (median follow-up, 38.5 months). Carcinomas were detected in 4 of 22 (18%) cases submitted as IND (median progression-free survival of 62 months), in 4 of 25 (15%) cases of LGD (median progression-free survival of 60 months), in 20 of 33 cases of HGD (median progression-free survival, 8 months), and all 13 (100%) cases submitted as adenocarcinoma. Grade on initial biopsy correlated significantly with progression to invasive carcinoma (log-rank P =.0001). Majority diagnosis was achieved in 99 of the cases. Using the majority diagnoses, no invasive carcinomas were found in 50 cases of BE (median follow-up, 48 months), and carcinomas were detected in 1 of 7 (14%) IND cases (80% progression-free survival at 2 months), 3 of 15 (20%) LGD (median progression-free survival, 60 months), 9 of 15 (60%) HGD (median progression-free survival, 7 months), and all 12 (100%) carcinoma. Initial grading again correlated significantly with progression to invasive carcinoma (log-rank P =.0001). However, there were 39 cases without a majority diagnosis. Among these, no carcinomas developed in 8 cases with an average score between BE and IND. Carcinomas were detected in 9 of 21 (43%) cases with an average score between IND and LGD, and 7 of 10 (70%) cases with an average score between LGD and HGD. There were ulcers in 8 of 39 cases (20%) of the "no-majority" group and in 13 of 99 (13%) of the majority cases. Of 21 total ulcerated cases, cancer was demonstrated in 15 (71%) of these on follow-up. These data support combining the IND and LGD categories for surveillance purposes. Cases without dysplasia may be followed up conservatively. The data obtained from submitted diagnoses as opposed to those from blind review suggest that knowledge of the clinical findings aids in diagnosis. The data also support the assertion that HGD is strongly associated with invasive carcinoma. Rebiopsy of ulcerated areas should be considered because they may harbor malignancy. Histologic grading of dysplasia using established criteria is a powerful prognosticator in BE. HUM PATHOL 32:379-388.

Adolescent↗

Special histologic stains are rarely beneficial for the evaluation of HIV-related gastrointestinal infections.

During a 28-month period, endoscopic mucosal biopsy specimens from all HIV-infected patients were submitted for routine histologic evaluation. Immunoperoxidase staining for cytomegalovirus and herpesvirus antigens (esophagus), mycobacterial and fungal staining, and Gram staining of mucosal biopsy specimens were done. Special fungal and acid-fast stains were selectively performed in patients with absolute CD4 cell counts of less than 200 cells per microliter (200 x 10(6)/L) and/or with diarrhea and or wasting syndrome. Treatment was based on the endoscopic and histologic findings, and long-term follow-up was performed. The 121 symptomatic HIV-infected patients underwent 221 upper and/or lower endoscopies with 285 biopsy sites. The sensitivity and specificity of H&E staining for the diagnosis of gastrointestinal cytomegalovirus were 97% and 100%, respectively. The results of fungal and mycobacterial stains neither altered therapy nor identified previously undiagnosed infections in any patient. Long-term follow-up revealed no patient in whom an infection was missed on routine H&E, which affected outcome. Routine H&E staining is accurate for the diagnosis of gastrointestinal opportunistic infections in HIV-infected patients. Special histologic stains for fungal, mycobacterial, and viral infections did not increase the diagnostic yield or alter medical therapy but doubled the costs.

AIDS-Related Opportunistic Infections↗

Declining prevalence of opportunistic gastrointestinal disease in the era of combination antiretroviral therapy.

OBJECTIVE: Opportunistic disorders (OD) are the most frequent GI manifestations of the acquired immunodeficiency syndrome (AIDS). Since the introduction of highly active antiretroviral therapy (HAART), there appears to be have been a reduction in the incidence of many of these OD; however, the effect of HAART on the prevalence of GI OD has not been well studied. METHODS: From 4/95 through 3/98, all HIV (HIV)-infected patients undergoing GI endoscopy were prospectively identified; mucosal biopsies were obtained in a standardized fashion and histological specimens were examined by a single GI pathologist. Patients were divided into three groups based on the time of evaluation: group I: 4/95 to 3/96; group II: 4/96 to 3/97; and group III: 4/97 to 3/98. RESULTS: A total of 166 patients (90% men; mean age 36+/-10 yr; median CD4 lymphocyte count 62 cells/microl, range 2-884, median viral RNA level 1,357 copies/ml, range undetectable to 7,721,715) underwent 279 upper and/or lower endoscopies during the study period. There were no statistical differences in patients' demographics and indications for endoscopy although the CD 4 lymphocyte count was higher in group III. The percentage of patients receiving HAART at the time of endoscopy increased from 0% to 57% over the three periods (p<0.01), and the percentage of patient receiving combination antiretroviral therapy increased from 37% to 82% over the study period (p<0.01). In contrast, the prevalence of OD decreased from 69% (group I) to 13% (group III) (p<0.01), whereas the prevalence of non-OD, including a normal endoscopy increased from 31% to 87% (p<0.01). CONCLUSIONS: GI OD now seem to be an uncommon problem in HIV-infected patients undergoing endoscopy despite a low CD4 lymphocyte count, and this reduction of OD was associated with the use of HAART.

AIDS-Related Opportunistic Infections↗

Diagnosis of gastrointestinal graft-versus-host disease.

Allogeneic bone marrow transplantation is becoming increasingly performed for a variety of disorders but primarily for hematological malignancies. Graft-versus-host disease (GVHD), which often involves the GI tract, is one of the most common complications of this type of transplantation. The diagnosis of GI GVHD can be difficult to establish because of the nonspecific nature of associated symptoms, few diagnostic endoscopic findings, and potential difficulty in making a histological diagnosis. In this review, we summarize current concepts and controversies regarding the diagnostic evaluation for GI GVHD.

Biopsy↗

Cocaine-associated ischemic colitis.

Cocaine use can result in various gastrointestinal complications, including gastric ulcerations, retroperitoneal fibrosis, visceral infarction, intestinal ischemia, and gastrointestinal tract perforation. We report cocaine-associated colonic ischemia in three patients and review the literature. Including ours, 28 cases have been reported, with a mean patient age of 32.6 years (range, 23 to 47 years); 53.5% were men and 46.5% were women. The interval between drug ingestion and onset of symptoms varied from 1 hour to 2 days. Cocaine is a potentially life-threatening cause of ischemic colitis and should be included in the differential diagnosis of any young adult or middle-aged patient with abdominal pain and bloody diarrhea, especially in the absence of estrogen use or systemic disorders that can cause thromboembolic events, such as atrial fibrillation.

Abdominal Pain↗

The atypical colitides.

Collangenous colitis is a clinicopathologic syndrome characterized by (1) chronic watery diarrhea and crampy abdominal pain and (2) distinctive colorectal histopathology that includes a subepithelial collagen band, prominent chronic inflammation in the lamina propria, and increased intraepithelial lymphocytes. Lymphocytic colitis has similar clinical features to collangenous colitis, the main symptom being chronic watery diarrhea. Diversion colitis is an inflammatory process that arises in segments of the large intestine that are excluded from the fecal stream. This condition usually occurs in patients with ileostomy or colostomy when a mucous fistula or Hartmann's pouch has been left.

Colitis↗

Prevalence of polycystic ovary syndrome in women seeking treatment from community electrologists. Alabama Professional Electrology Association Study Group.

OBJECTIVE: To determine the prevalence of the polycystic ovary syndrome (PCOS) among women seeking electrology, clients presenting to nine electrology centers completed a questionnaire. STUDY DESIGN: Women with potential risk factors were referred to the University of Alabama at Birmingham. They underwent a detailed history and physical examination, including hirsutism scoring by a modified Ferriman-Gallwey (F-G) method. Serum was assayed for total testosterone, sex hormone binding globulin and dehydroepiandrosterone sulfate. RESULTS: Three hundred fifteen (40%) of 779 patients had potential risk factors for hyperandrogenism and were referred. Eighty-two (26%) completed their evaluation. Six were excluded secondary to prepubertal or menopausal status. Of the remaining 76 patients, 20% had F-G scores of 7 or 8, 13% had scores of 9 or 10, and 21% had scores > 10. Forty-nine (64%) patients reported irregular menstrual cycles. Sixty-four patients were not receiving hormonal therapy: 25 reported regular menstrual cycles, and 39 reported irregular cycles. Seventeen (68%) of the 25 had at least one abnormal androgen value, while 33 (85%) of the 39 women had at least one abnormal value (nonsignificant difference). Overall, PCOS was evident in 39 of the 76 women, or 12% of the 315 patients who were referred for further evaluation. CONCLUSION: Thirty-nine of the 315 referred patients (12%) fulfilled the diagnostic criteria for PCOS. However, they were not receiving medical care for this condition. In addition, this percentage is a conservative estimate in that 74% of the referred patients did not pursue a medical evaluation. Therefore, efforts to educate both electrologists and their clients of the possibility of underlying endocrine disorders and subsequent metabolic morbidity should be undertaken.

Adult↗

Budesonide enema for the treatment of active, distal ulcerative colitis and proctitis: a dose-ranging study. U.S. Budesonide enema study group.

BACKGROUND & AIMS: Budesonide is a highly potent topical glucocorticosteroid that is characterized by low systemic availability as a result of high first-pass hepatic metabolism. The aim of this study was to evaluate the efficacy and safety of three doses of an enema preparation of budesonide in patients with active distal ulcerative colitis/proctitis. METHODS: In a double-blind multicenter trial, 233 patients were randomized to receive either a placebo enema or budesonide enema at a dose of 0.5 mg/100 mL, 2.0 mg/100 mL, or 8.0 mg/100 mL. The primary efficacy variables were an improvement of sigmoidoscopic inflammation grade, total histopathology score, and remission rates. Effects on cortisol concentrations were also assessed. RESULTS: After 6 weeks of treatment, there was significant improvement in sigmoidoscopy and histopathology scores in the budesonide 2.0-mg and 8.0-mg dose groups compared with placebo. Remission was achieved in 19% of patients in the 2.0-mg budesonide group (P </= 0.050) and 27% of patients in the 8.0-mg budesonide group (P </= 0.001) compared with 4% in the placebo group. More than 90% of all budesonide patients had a normal adrenocorticotropin (ACTH)-stimulated cortisol response at the last visit. The budesonide enemas were well tolerated. CONCLUSIONS: Budesonide enema is both effective and safe for the treatment of active distal ulcerative colitis/proctitis. A dose of 2. 0 mg/100 mL budesonide is the lowest effective dose.

Adult↗

Preoperative terminal ileal and colonic resection histopathology predicts risk of pouchitis in patients after ileoanal pull-through procedure.

OBJECTIVE: This study seeks to compare the histopathology of preoperative terminal ileal and colonic resection specimens with pouch biopsies after the ileoanal pull-through (IAPT) procedure. SUMMARY BACKGROUND DATA: Pouchitis is the most frequent complication of transanal continent reservoirs in patients after IAPT. METHODS: The authors conducted 751 consecutive pouch biopsies on 73 patients with inflammatory bowel disease or familial adenomatous polyposis who underwent IAPT by a single surgeon over a 10-year period. In this preliminary report, a pathologist, in blinded fashion, has graded 468 of the IAPT pouch biopsies and 67 of the patients' preoperative terminal ileal and colonic resection histopathology to date. Colonic histopathology was graded by the extent and severity of disease, terminal ileal and pouch histopathology by active inflammation, chronic inflammation, lymphocyte aggregates, intraepithelial lymphocytes, eosinophils, and villous blunting. RESULTS: Extent of colonic disease (gross and microscopic) was a significant predictor of active inflammation in subsequent IAPT pouch biopsy specimens. Also, the gross extent of colonic disease exhibited a significant linear association with pouch inflammation. However, the severity of colonic disease was not significantly predictive of active inflammation in subsequent IAPT pouch biopsies. Terminal ileal active and chronic inflammation were significant predictors of subsequent IAPT pouch inflammation. Although lymphocyte aggregates and intraepithelial lymphocytes were not predictive, terminal ileum eosinophils and villous blunting were significant predictors of active inflammation in subsequent IAPT pouch biopsy specimens. CONCLUSIONS: Preoperative terminal ileal and colonic histopathology predicts active inflammation of pouches after IAPT. Patients who are preoperatively assessed to have extensive disease of the colon, ileal disease ("backwash ileitis"), or both appear to be at greater risk for the development of pouchitis after IAPT.

Adenomatous Polyposis Coli↗

Bioactivity of autologous irradiated renal cell carcinoma vaccines generated by ex vivo granulocyte-macrophage colony-stimulating factor gene transfer.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-transduced, irradiated tumor vaccines induce potent, T-cell-mediated antitumor immune responses in preclinical models. We report the initial results of a Phase I trial evaluating this strategy for safety and the induction of immune responses in patients with metastatic renal cell carcinoma (RCC). Patients were treated in a randomized, double-blind dose-escalation study with equivalent doses of autologous, irradiated RCC vaccine cells with or without ex vivo human GM-CSF gene transfer. The replication-defective retroviral vector MFG was used for GM-CSF gene transfer. No dose-limiting toxicities were encountered in 16 fully evaluable patients. GM-CSF gene-transduced vaccines were equivalent in toxicity to nontransduced vaccines up to the feasible limits of autologous tumor vaccine yield. No evidence of autoimmune disease was observed. Biopsies of intradermal sites of injection with GM-CSF gene-transduced vaccines contained distinctive macrophage, dendritic cell, eosinophil, neutrophil, and T-cell infiltrates similar to those observed in preclinical models of efficacy. Histological analysis of delayed-type hypersensitivity responses in patients vaccinated with GM-CSF-transduced vaccines demonstrated an intense eosinophil infiltrate that was not observed in patients who received nontransduced vaccines. An objective partial response was observed in a patient treated with GM-CSF gene-transduced vaccine who displayed the largest delayed-type hypersensitivity conversion. No replication-competent retrovirus was detected in vaccinated patients. This Phase I study demonstrated the feasibility, safety, and bioactivity of an autologous GM-CSF gene-transduced tumor vaccine for RCC patients.

Adult↗

NHE2 and NHE3 are human and rabbit intestinal brush-border proteins.

Rabbit NHE2 and NHE3 are two epithelial isoform Na+/H+ exchangers (NHE), the messages for which are found predominantly and entirely, respectively, in renal, intestinal, and gastric mucosa. The current studies used Western analysis and immunohistochemistry to identify and characterize the apical vs. basolateral membrane distribution of NHE2 and NHE3 in intestinal epithelial cells. Based on Western analysis, NHE2 and NHE3 both are present in brush-border but not basolateral membranes of small intestine. Both NHE2 and NHE3 are 85-kDa proteins. Consistent with Western analysis, NHE2 and NHE3 are immunolocalired to the brush-border but not basolateral membranes of villus epithelial cells, but not goblet cells, in human jejunum and ileum and in surface epithelial cells in the ascending and descending colon and rectum. In addition, NHE2 and NHE3 are present in small amounts in the crypt cell brush border of human jejunum, ileum, ascending and descending colon, and rectum. In rabbit jejunum, ileum, and ascending colon, NHE2 and NHE3 are present in the brush border of epithelial and not goblet cells, again much more in the villus (small intestine)/ surface cells (colon) than the crypt. NHE2 but not NHE3 is present in the brush border of rabbit descending colon surface cells and in small amounts in crypt cells. NHE2 and NHE3 are both human and rabbit small intestinal and colonic epithelial cell brush-border Na+/H+ exchanger isoforms that colocalize in all intestinal segments except rabbit descending colon, which lacks NHE3.

Animals↗

Eosinophilic esophagitis attributed to gastroesophageal reflux: improvement with an amino acid-based formula.

BACKGROUND & AIMS: Treatment for gastroesophageal reflux may be ineffective in patients with an eosinophilic infiltration of the esophagus. The aim of this study was to investigate whether unremitting symptoms of gastroesophageal reflux and biopsy abnormalities of the esophagus may be associated with the ingestion of certain foods. METHODS: Ten children previously diagnosed with gastroesophageal reflux by standard testing with long-standing symptoms (median, 34.3 months; range, 6-78 months) despite standard antireflux therapies, including Nissen fundoplication in 6 patients, were fed the elemental formulas Neocate or Neocate-1-Plus (Scientific Hospital Supplies Inc., Gaithersburg, MD) for a minimum of 6 weeks. Each child had repeat endoscopy followed by open food challenges. RESULTS: While receiving the formulas, patients had either resolution (n = 8) or improvement (n = 2) of symptoms. On follow-up esophageal biopsy, the maximal intraepithelial eosinophil counts decreased significantly before (median, 41; range, 15-100) to after (median, 0.5; range, 0-22) the formula trial (P = 0.005). Other reactive epithelial changes of the esophageal mucosa also improved significantly. All patients redeveloped their previous symptoms on open food challenges. CONCLUSIONS: Chronic gastrointestinal symptoms and histological changes of the esophagus unresponsive to standard treatments for gastroesophageal reflux were improved by the use of elemental formulas. Symptoms recurred when specific dietary proteins were reintroduced during open food challenges. The mechanism of these observations is unknown.

Adolescent↗