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C M Surawicz

Publications and source records attributed to C M Surawicz.

At least 55 records · Page 3Linked to original sources
PubMed1988

Self-limited cytomegalovirus colitis in immunocompetent individuals.

We report 3 cases of isolated acute cytomegalovirus colitis in immunocompetent individuals. Each case was documented by the presence of cytomegalovirus inclusions in colonic biopsy specimens. All had a self-limited illness. Two of these cases occurred after anal intercourse and 1 case had no probable known cause. At follow-up from 2 to 6 yr later, none of the 3 patients has had any gastrointestinal symptoms. Additional biopsy specimens were obtained from 2 patients and no evidence of residual cytomegalovirus was seen by light microscopy or by in situ hybridization. Although cytomegalovirus colitis in immunosuppressed individuals is well recognized, these are the first reports of a nonfatal cytomegalovirus colitis in immunocompetent hosts.

Acute Disease↗
PubMed1988

Comparison of human jejunal and ileal fat absorption by electron microscopy.

Morphologic and physiologic experiments in rodents have demonstrated differences between jejunal and ileal fat absorption. Compared with the rat jejunum, absorbed lipid particles within rat ileal absorptive cells are larger and exit at a slower rate. To evaluate the relevance of these observations to humans, we studied jejunal and ileal ultrastructure in 3 volunteers, each of whom had an intact small intestine and an ileostomy postcolectomy for ulcerative colitis. Proximal jejunal biopsy specimens were obtained via a hydraulic tube after an overnight fast and again after a 20-min intrajejunal lipid infusion. On a separate day, terminal ileal biopsy specimens were taken via the stoma with a small steerable suction biopsy tube after an overnight fast and again after a 20-min intraileal infusion of the same lipid mixture. One volunteer underwent biopsy after a 60-min ileal infusion of a digested meal of higher lipid content. Electron microscopy of fasting human jejunal absorptive cells revealed obvious smooth endoplasmic reticulum in the extreme apical region beneath the terminal web; very low density lipoprotein particles were observed within smooth endoplasmic reticulum and Golgi cisternae. In contrast, fasting human ileal absorptive cells contained less apical smooth endoplasmic reticulum and fewer or no very low density lipoprotein particles. After the 20-min infusion of lower-lipid content, human jejunal and ileal absorptive cells were indistinguishable because they contained fat particles of the same size and number within smooth endoplasmic reticulum, Golgi cisternae, and extracellular spaces. After the 60-min ileal infusion of higher-lipid content, human ileal absorptive cells appeared to be the same as those of the human jejunum after similar lipid infusions. Our observations of the ultrastructural similarity in human jejunal and ileal absorptive cells after lipid infusions contrasts with those in rodents and may reflect species-specific differences in mechanisms of fat absorption.

Adult↗
PubMed1988

Observer variation in the diagnosis of dysplasia in Barrett's esophagus.

The potential value of biopsy surveillance of patients with Barrett's esophagus for dysplasia is diminished by a lack of agreement on the diagnostic criteria for dysplasia. In a preliminary consensus conference, experienced gastrointestinal pathologists from four medical centers agreed on criteria for a five-tiered histologic classification of dysplasia in Barrett's esophagus--negative for dysplasia, indefinite for dysplasia, low-grade dysplasia, high-grade dysplasia, and intramucosal carcinoma. Eight morphologists in the four centers tested the criteria for interobserver agreement by examining a set of coded slides that had been chosen to include some especially difficult interpretative problems in all five histologic classifications. Interobserver agreement of 85 and 87% was achieved in successive reviews when the combined group of high-grade dysplasia and intramucosal carcinoma was compared with the combined group of low-grade dysplasia, indefinite for dysplasia, and negative for dysplasia. Comparison of other groups yielded less agreement. For example, negative for dysplasia could be distinguished from all other diagnoses with an interobserver agreement of 72%. We conclude that experienced gastrointestinal morphologists can diagnose high-grade dysplasia and intramucosal carcinoma with a high degree of agreement and thus can detect those patients who may need immediate rebiopsy or esophageal resection. Either further refinement of histologic criteria or alternate diagnostic methods will be needed to achieve the reproducible diagnosis of indefinite changes and low-grade dysplasia. This is important because patients with such changes theoretically merit closer endoscopic surveillance.

Barrett Esophagus↗
PubMed1988

The role of rectal biopsy in infectious colitis.

Rectal biopsy has a dual role in the diagnosis of infectious colitis. It can usually differentiate acute self-limited colitis (ASLC) from idiopathic inflammatory bowel disease (IBD), and it can also sometimes diagnose the specific infection in ASLC. Seven histologic features reliably differentiate IBD from ASLC: crypt distortion, crypt atrophy, a villous appearance of the surface epithelium, epithelioid granulomas, basally located isolated giant cells, basal lymphoid aggregates, and a lamina propria infiltrate of both acute and chronic inflammatory cells. One or more of these findings is frequent in rectal biopsies from patients with IBD, but rare in ASLC. Thus, the diagnosis of ASLC is made by the absence of the findings that characterize IBD. The usual histopathological picture of ASLC is nonspecific: normal architecture and increased numbers of acute inflammatory cells in the lamina propria. Certain findings may suggest a specific diagnosis. Granulomas may be present in specimens from homosexual men with proctitis due to C. trachomatis or T. pallidium. Granulomas are also present in schistosomiasis, tuberculosis, histoplasmosis, and yersinia enterocolitica infection. Typical viral inclusions can be seen in herpes simplex virus type II and cytomegalovirus infections. Specific parasites may be seen in biopsies from patients with amebiasis, schistosomiasis, and cryptosporidiosis. Intestinal spirochetosis is frequent in male homosexuals.

Acute Disease↗
PubMed1987

Gastric protection by misoprostol against 1,300 mg of aspirin. An endoscopic dose-response study.

Misoprostol at a dose of 200 micrograms inhibits gastric acid secretion and protects the gastric mucosa against the injurious effects of a single 1,300-mg dose of aspirin. The purpose of this study was to determine whether lower subantisecretory doses of misoprostol protect the gastric mucosa in this single-dose aspirin model. Protection was defined as no more than 10 hemorrhagic spots and no more than two hemorrhagic streaks. A total of 140 men participated in the two phases of the study. In the first phase, groups of 10 subjects each received placebo or misoprostol in doses of 200 micrograms, 100 micrograms, 50 micrograms, or 25 micrograms in a double-blind design. All misoprostol doses protected 50 to 70 percent of subjects as compared with 20 percent of subjects in the placebo group. To expand the number of observations, 90 additional subjects in groups of 30 each were evaluated after receiving misoprostol 50 micrograms or 25 micrograms or placebo. Misoprostol 50 micrograms protected 14 of 30 subjects (47 percent), 25 micrograms protected 11 of 30 (37 percent), and placebo protected six of 30 (20 percent). The dose-response trend was statistically significant (p less than 0.05). It is concluded that misoprostol protects the gastric mucosa against a single 1,300-mg dose of aspirin and that there is a significant dose-response relationship.

Adolescent↗
PubMed1987

Intestinal spirochetosis in homosexual men.

Previous studies have demonstrated intestinal spirochetosis in rectal biopsy specimens from 2 to 7 percent of heterosexual and 36 percent of homosexual patients, but the role of intestinal spirochetosis in the pathogenesis of intestinal disease remains unclear. To assess the clinical, histologic, and microbiologic correlates of intestinal spirochetosis in a high-risk group, rectal biopsy specimens from 130 homosexual men, 92 percent of whom had intestinal symptoms, were evaluated. All men were extensively evaluated for rectal and enteric pathogens. Intestinal spirochetosis was identified in rectal biopsy specimens from 39 (30 percent) men; 15 percent of biopsy specimens revealed intestinal spirochetosis on hematoxylin and eosin plus alcian blue staining, and positive results were found in 30 percent on silver staining. No rectal biopsy specimens from 79 control patients with a variety of gastrointestinal symptoms demonstrated evidence of spirochetosis on hematoxylin and eosin, alcian blue, or silver staining (p less than 0.0001). Fifty-six percent of rectal biopsy specimens from men with intestinal spirochetosis were normal, and no specific histologic abnormality was correlated with intestinal spirochetosis. There were no differences in the presence of or type of intestinal symptoms, sigmoidoscopic appearance of the mucosa, type of sexual practice, or prior antibiotic use in men with and without spirochetosis. Other intestinal pathogens were frequent in both groups, and only rectal gonorrhea was significantly associated with intestinal spirochetosis. It is concluded that homosexual men with intestinal symptoms have an increased prevalence of spirochetosis, often in association with Neisseria gonorrhoeae. Independent association of spirochetosis with clinical or histologic findings could not be demonstrated.

Biopsy↗
PubMed1986

Inflammatory polyposis two years after ischemic colon injury.

Inflammatory polyps occur in association with ulcerative colitis, Crohn's disease, and other inflammatory diseases of the colon. The occurrence of inflammatory polyps following ischemic colitis has not been well documented. A 49-year-old man suffered complications of hypoperfusion, including renal insufficiency, hepatic failure, shock lung, and ischemic colitis following emergent repair of an acute aortic dissection. Although the renal, hepatic, and pulmonary complications resolved, the patient continued to experience intermittent bloody diarrhea more than two years after his initial presentation. Barium enema and colonoscopy revealed numerous pedunculated polyps in the descending and sigmoid colon. Histopathology of the polyps removed by snare electrocautery showed them to be inflammatory polyps. We believe these are the sequelae of chronic ischemic colitis.

Colitis↗
PubMed1986

Spectrum of rectal biopsy abnormalities in homosexual men with intestinal symptoms.

Homosexually active men have frequent intestinal and rectal symptoms resulting from sexually acquired gastrointestinal infections. We evaluated the histologic findings in rectal biopsy specimens obtained from 89 homosexual men with intestinal symptoms and 11 homosexual men without intestinal symptoms. All had undergone comprehensive microbiologic evaluation for rectal and enteric pathogens. Rectal biopsy specimens were evaluated without knowledge of clinical or microbiologic data by a standardized method for the presence or absence of abnormal histologic features. Forty-six percent of specimens from symptomatic men and 27% of those from asymptomatic men were abnormal. Acute inflammation was the most frequent histologic abnormality and was more frequent in men who had pathogens (51%) than men without pathogens (24%, p less than 0.02). Acute but not chronic inflammation was seen also in specimens from homosexual men without intestinal symptoms. Intestinal spirochetosis was present in specimens from 23 (26%) of the symptomatic and 5 (45%) of the asymptomatic men. In 5 of the 89 symptomatic men, biopsy features of idiopathic inflammatory bowel disease (IIBD) were present; all 5 of these men were infected with either Treponema pallidum or Chlamydia trachomatis. Features of IIBD were present in 25% of those infected with C. trachomatis or T. pallidum. Chronic inflammation was more frequent in men infected with C. trachomatis, syphilis, or herpes simplex virus type II: 31% vs. 3%, p = 0.0002. Acute inflammation was present in specimens from men with proctitis or proctocolitis and enteritis as well as in those from asymptomatic men, whereas chronic inflammation was present only in specimens from men with proctitis or proctocolitis. Both acute and chronic inflammation were more frequent when biopsy specimens of the abnormal mucosa were examined. When specimens from men with single infections were analyzed, histology was rarely diagnostic. We conclude that acute inflammation is frequent in rectal biopsy specimens from symptomatic and asymptomatic homosexual men; chronic inflammation is infrequent, but when present is significantly associated with syphilis, herpes simplex virus type II, and C. trachomatis infection.

Adult↗
PubMed1986

Bacteremia with gastrointestinal endoscopic procedures.

The authors have reviewed 40 prospective studies of bacteremia with gastrointestinal procedures. Endoscopic procedures with a low mean frequency of bacteremia were esophagogastroduodenoscopy (4.2%), endoscopic retrograde cholangiopancreatography (5.6%), colonoscopy (2.2%), and sigmoidoscopy (4.9%). A higher mean frequency of bacteremia was encountered with esophageal dilation (45%) and variceal sclerotherapy (31%), although the number of patients studied was small. Potentially pathogenic organisms, such as Streptococcus viridans, Staphylococcus aureus, and Staphylococcus epidermidis have been isolated. Recommendations for antibiotic prophylaxis are reviewed. Less cumbersome regimens encourage compliance and are preferred.

Aged↗
PubMed1984

Prevention of acute aspirin-induced gastric mucosal injury by 15-R-15 methyl prostaglandin E2: an endoscopic study.

The deleterious effects of aspirin on gastric mucosa have been well documented in experimental and clinical studies. Prostaglandins offer a potential method by which this injury may be prevented. In these studies, we developed a single-dose endoscopic assay system of aspirin-induced gastric mucosal injury in normal volunteers. With this system, 27 of 30 volunteers (90%) demonstrated severe mucosal injury after ingestion of aspirin. Subsequently, we evaluated whether pretreatment with 15-R-15 methyl prostaglandin E2 prevented severe injury after ingestion of aspirin. Following an initial dose-response study, a double-blind crossover trial was performed using pretreatment with placebo or with 10-micrograms doses of 15-R-15 methyl prostaglandin E2 for 24 h before treatment with aspirin. The results of this trial indicate that prostaglandin pretreatment significantly prevented the occurrence of endoscopically visible severe gastric mucosal injury after single-dose aspirin administration.

Adolescent↗
PubMed1984

Rectal biopsy helps to distinguish acute self-limited colitis from idiopathic inflammatory bowel disease.

A retrospective blind evaluation of rectal biopsy specimens from 44 patients with acute self-limited colitis and 104 patients with idiopathic inflammatory bowel disease was done. Seven histologic features proved highly discriminant because they occurred often in idiopathic inflammatory bowel disease but rarely, if at all, in acute self-limited colitis. The features with a high predictive probability (87%-100%) of diagnosing idiopathic inflammatory bowel disease were distorted crypt architecture, increased numbers of both round cells and neutrophils in the lamina propria, a villous surface, epithelioid granuloma, crypt atrophy, basal lymphoid aggregates, and basally located isolated giant cells. One or more of these features was present in 79% of all idiopathic inflammatory bowel disease cases. They were seen in both acute and chronic idiopathic inflammatory bowel disease. The biopsy features favoring acute self-limited colitis were less useful. Biopsy diagnosis of acute self-limited colitis is thus primarily based on the absence of histologic criteria favoring idiopathic inflammatory bowel disease. This study provides objective validation of histologic criteria in rectal biopsy that help differentiate acute self-limited colitis from idiopathic inflammatory bowel disease.

Acute Disease↗
PubMed1982

Serial sectioning of a portion of a rectal biopsy detects more focal abnormalities: a prospective study of patients with inflammatory bowel disease.

The diagnostic accuracy of two different methods of sectioning rectal biopsies was evaluated prospectively. The frequency of focal and diffuse findings in more than 80 serial sections from a limited portion of the well-oriented areas of 74 biopsies was compared with that found in three or more step sections distributed throughout the well-oriented areas of the same rectal biopsies from patients with known or suspected inflammatory bowel disease (IBD). Significantly more focal abnormalities (granulomas, giant cells, histiocytic collections) were detected by serial sectioning than by step sectioning. For example, serial sectioning increased the ability to detect granulomas by 50% compared to step sectioning. Serial sectioning provided no significant advantage in the detection of diffuse abnormalities (abnormal architecture, decreased mucus, nonspecific inflammation, crypt abscess). Serially sectioning part of a biopsy is superior to step sectioning more of the biopsy in detecting focal abnormalities.

Biopsy↗
PubMed1981

Linolenate transport by human jejunum: presumptive evidence for portal transport at low absorption rates.

Are the small quantities of linolenic acid (LA) in a meal absorbed via a different pathway than the higher concentrations of the other long-chain fatty acids (LCFA) in a mixed meal? To answer this question, varying LA concentrations were infused into the human jejunum via a quadruple-lumen hydraulic biopsy tube. After 0.01-mM LA infusion, no LA was found in triglyceride (TG) extracted from jejunal biopsies, although 58% of the phospholipid plus monoglyceride fraction (PL + MG) and 42% of the LCFA fraction were LA. In marked contrast, after 5.0-mM LA infusion, 60% of the TG, 28% of the PL + MG, and only 3% of the LCFA fractions were LA. By electron microscopy, mostly very low-density lipoprotein-sized (less than 750 A) particles were seen within jejunal fasting biopsies and in biopsies after 0.01, 0.1, or 1.0-mM LA infusions; mostly chylomicrons (greater than 750 A) were seen within jejunal biopsies after 5.0-mM LA infusion. We conclude that LA at its usual very low dietary concentrations is absorbed mostly as invisible LCFA and PL molecules; whereas at higher concentrations it is absorbed like most dietary fat via lacteals as TG and PL within visible chylomicrons.

Biological Transport↗
PubMed1981

Rectal biopsy in the diagnosis of Crohn's disease: value of multiple biopsies and serial sectioning.

We performed a retrospective evaluation of 243 rectal biopsies from 90 patients who eventually had Crohn's disease proven clinically or by surgery. A portion of each rectal biopsy was serially sectioned. Twenty-five of the 90 patients (28%) had epithelioid granulomas. Half of these patients had an epithelioid granuloma in only one of two or more biopsies. Sixteen percent of these granulomas were so small as to be seen in only six or less successive serial 4-microM sections. This high yield of granulomas is probably attributable to the examination of at least 90 serial sections, usually from each of two rectal biopsies per patient. Using partial serial sectioning, epithelioid granulomas were found almost as frequently in grossly normal as in grossly abnormal appearing mucosa. No granulomas were seen in suitable controls including normals and patients with ulcerative colitis or other diseases. When the differential diagnosis between idiopathic ulcerative colitis and Crohn's disease is uncertain, we recommend taking two rectal biopsies and serially sectioning part of each.

Adolescent↗
PubMedDate not supplied

Pseudomembranous colitis: causes and cures.

Clostridium difficile is the most common nosocomial pathogen of the gastrointestinal tract and has increased in frequency over time. Typical symptoms of C. difficile infection include diarrhea, which is usually nonbloody, or colitis associated with severe abdominal pain, fever and/or gross or occult blood in the stools. Pseudomembranous colitis (PMC), the severest form of this disease, occurs as a result of a severe inflammatory response to the C. difficile toxins. This review focuses on PMC, as this severe form is associated with the greatest medical concern. Diagnosis rests on detection of C. difficile in the stool, either by culture, tissue culture assay for cytotoxin B or detection of antigens in the stool by rapid enzyme immunoassays. Oral therapy with metronidazole 250 mg 4 times a day for 10 days is the recommended first-line therapy. Vancomycin is also effective, but its use must be limited to decrease the development of vancomycin-resistant organisms such as enterococci. Vancomycin (125-500 mg 4 times a day for 10 days) should be limited to those who cannot tolerate or have not responded to metronidazole, or when metronidazole use is contraindicated, as in the first trimester of pregnancy. A therapeutic response within a few days is usual. Recurrence of symptoms after antibiotics occurs in 20% of cases and is associated with persistence of C. difficile in the stools. Further recurrences then become more likely. Therapy with antibiotics in a pulsed or tapered regimen is often effective as are efforts to normalize the fecal flora. The yeast Saccharomyces boulardii has been proven in controlled trials to reduce recurrences when given as an adjunct to antibiotic therapy. Careful hand washing and environmental decontamination are necessary to prevent epidemics.

Anti-Bacterial Agents↗