Biomedical subjects

W S Harmsen

Publications and source records attributed to W S Harmsen.

At least 19 recordsLinked to original sources

PubMed2006

Quantitative measurement and visual assessment of ileal Crohn's disease activity by computed tomography enterography: correlation with endoscopic severity and C reactive protein.

BACKGROUND: Few studies have correlated computed tomography (CT) enterography findings with endoscopic severity and C reactive protein (CRP) concentrations. AIM: To examine whether small bowel inflammation at CT enterography correlates with endoscopic severity and CRP in patients with Crohn's disease (CD). METHODS: CT enterography datasets from 143 CD patients undergoing ileoscopy were examined for three different CT parameters: CT bowel enhancement, as defined by the ratio of terminal ileal versus control ileal loop attenuation; vascular enlargement of the vasa recta ("the comb sign"); and mesenteric fat density. Correlations between CT scan parameters, endoscopy, and histology severity scores, and CRP were assessed using Spearman's rank correlation and logistic regression. RESULTS: Endoscopic score was significantly correlated with CT bowel enhancement, comb sign, and fat density (Spearman correlation coefficients 0.33-0.39; p<0.001). Correlations with histological inflammation were strongest for bowel enhancement (r = 0.34-0.38; p<0.001). CRP was elevated in patients with increased fat density versus those with increased bowel enhancement only (median 0.96 v 0.23, p = 0.002). CRP did not differ significantly between patients without evidence of active Crohn's and those with bowel enhancement and endoscopic inflammation not involving the perienteric tissues by CT (median 0.24 v 0.36; p = 0.38). CONCLUSION: Quantitative measures of bowel enhancement at CT enterography correlate with endoscopic and histological severity. CRP correlates with radiological findings of perienteric inflammation (increased fat density), but not of inflammation limited to the small bowel wall, underscoring the potential role of perienteric inflammation in CRP response in CD.

Adolescent↗

PubMed2006

Survival and cause specific mortality in patients with inflammatory bowel disease: a long term outcome study in Olmsted County, Minnesota, 1940-2004.

BACKGROUND AND AIMS: We followed a population based cohort of patients with inflammatory bowel disease (IBD) from Olmsted County, Minnesota, in order to analyse long term survival and cause specific mortality. MATERIAL AND METHODS: A total of 692 patients were followed for a median of 14 years. Standardised mortality ratios (SMRs, observed/expected deaths) were calculated for specific causes of death. Cox proportional hazards regression was used to determine if clinical variables were independently associated with mortality. RESULTS: Fifty six of 314 Crohn's disease patients died compared with 46.0 expected (SMR 1.2 (95% confidence interval (CI) 0.9-1.6)), and 62 of 378 ulcerative colitis (UC) patients died compared with 79.2 expected (SMR 0.8 (95% CI 0.6-1.0)). Eighteen patients with Crohn's disease (32%) died from disease related complications, and 12 patients (19%) died from causes related to UC. In Crohn's disease, an increased risk of dying from non-malignant gastrointestinal causes (SMR 6.4 (95% CI 3.2-11.5)), gastrointestinal malignancies (SMR 4.7 (95% CI 1.7-10.2)), and chronic obstructive pulmonary disease (COPD) (SMR 3.5 (95% CI 1.3-7.5)) was observed. In UC, cardiovascular death was reduced (SMR 0.6 (95% CI 0.4-0.9)). Increased age at diagnosis and male sex were associated with mortality in both subtypes. In UC but not Crohn's disease, a diagnosis after 1980 was associated with decreased mortality. CONCLUSIONS: In this population based study of IBD patients from North America, overall survival was similar to that expected in the US White population. Crohn's disease patients were at increased risk of dying from gastrointestinal disease and COPD whereas UC patients had a decreased risk of cardiovascular death.

Adult↗

PubMed2005

Comparison of specimen processing and nucleic acid extraction by the swab extraction tube system versus the MagNA Pure LC system for laboratory diagnosis of herpes simplex virus infections by LightCycler PCR.

A total of 563 specimens (234 dermal and 329 genital swabs) from patients suspected of having herpes simplex virus (HSV) infections were processed using two different extraction methods (the MagNA Pure LC system and the swab extraction tube system [SETS]); HSV DNA was amplified by LightCycler PCR. HSV DNA was detected in 157 of 563 specimens (27.9%) processed by the MagNA Pure LC system and in 179 of 563 specimens (31.8%) processed by SETS (P < 0.0001). There was no specimen processed by the MagNA Pure LC extraction method that was positive only for HSV DNA. Of 157 specimens positive by both methods, HSV DNA copy levels were higher (using cycle crossover points [cycle threshold {C(T)}]) with SETS (mean C(T), 25.9 cycles) than with the MagNA Pure LC system (mean C(T), 32.0 cycles) (P < 0.0001). The time to process 32 samples was longer with the MagNA Pure LC extraction system (90 min) than with SETS (35 min). HSV DNA extraction using SETS is faster, less expensive, and more sensitive than the MagNA Pure LC system and could replace the latter for the laboratory diagnosis of HSV infections using LightCycler PCR.

Clinical Laboratory Techniques↗

PubMed2005

PSC-IBD: a unique form of inflammatory bowel disease associated with primary sclerosing cholangitis.

BACKGROUND: Inflammatory bowel disease associated with primary sclerosing cholangitis (PSC-IBD) may have a high prevalence of rectal sparing, backwash ileitis, and colorectal neoplasia. AIMS: To describe the clinical features and outcomes of PSC-IBD and compare these to a group of chronic ulcerative colitis (CUC) patients. METHODS: The medical records of all patients with PSC-IBD evaluated at the Mayo Clinic Rochester between 1987 and 1992 were abstracted for information on endoscopic and histological features, colorectal neoplasia, surgery, and other clinical outcomes. Patients referred for colorectal neoplasia and those who did not undergo colonoscopy with biopsies were excluded. A control group of CUC patients matched for sex, duration of IBD at first clinic visit, and calendar year of first clinic visit was identified, and similar information was abstracted. RESULTS: Seventy one PSC-IBD patients and 142 CUC patients without PSC were identified. Rectal sparing and backwash ileitis were more common in the PSC-IBD group (52% and 51%, respectively) than in controls (6% and 7%, respectively). Overall, colorectal neoplasia developed in 18 cases and 15 controls, including 11 cancers (seven cases and four controls). An increased risk of colorectal neoplasia or death was not detected in a matched analysis. Although the cumulative incidence of colorectal neoplasia was higher in cases (33%) than in controls (13%) at five years, this was of borderline statistical significance (p=0.054, unmatched log rank test). Overall survival from first clinic visit was significantly worse among cases (79% v 97%) at five years (p<0.001, unmatched log rank test). CONCLUSION: PSC-IBD is frequently characterised by rectal sparing and backwash ileitis. Colorectal neoplasia develops in a substantial fraction and overall survival is worse. PSC-IBD may represent a distinct IBD phenotype.

Adolescent↗

PubMed2004

Optimal testing parameters for blood cultures.

The effects of volume of blood, number of consecutive cultures, and incubation time on pathogen recovery were evaluated for 37,568 blood cultures tested with the automated BACTEC 9240 instrument (Becton Dickinson Diagnostic Instrument Systems) at a tertiary care center over the period of 12 June 1996 through 12 October 1997. When the results for this study were compared with previous data published for manual broth-based blood culture systems and patient samples obtained in the 1970s and 1980s, the following were found: (1) the percentage increase in pathogen recovery per milliliter of blood is less, (2) more consecutive blood culture sets over a 24-h period are required to detect bloodstream pathogens, and (3) a shorter duration of incubation is required to diagnose bloodstream infections. Guidelines developed in the 1970s and 1980s for processing and culturing blood may require revision.

Adult↗

PubMed2004

Comparison of the Roche LightCycler vanA/vanB detection assay and culture for detection of vancomycin-resistant enterococci from perianal swabs.

We compared the performance characteristics of a real-time PCR method, the LightCycler vanA/vanB detection assay (Roche Diagnostics Corporation, Indianapolis, Ind.) to that of Enterococcosel agar (BBL, Sparks, Md.) for direct detection of vancomycin-resistant enterococci (VRE) from 894 perianal stool swabs. For 421 of 894 swabs, the result for LightCycler PCR was compared to an Enterococcosel plate containing vancomycin at 6 microg/ml; for the remaining 473 swabs, the result for LightCycler PCR was compared to an Enterococcosel plate containing 8 microg/ml vancomycin. The LightCycler method produced considerably more positive results than either the Enterococcosel plate containing vancomycin at 6 microg/ml (n = 25 versus n = 11; sensitivity, 100%; specificity, 97%; positive predictive value [PPV], 42%; negative predictive value [NPV], 100%) or the Enterococcosel plate containing vancomycin at 8 microg/ml (n = 31 versus n = 10; sensitivity, 100%; specificity, 95%; PPV, 32%; NPV, 100%). When possible, additional testing, including culture, LightCycler PCR, and/or a conventional PCR method (PCR-restriction fragment length polymorphism assay), were performed on either the original specimens or original cultures or subsequent specimens for cases in which the original specimen was positive by LightCycler PCR but the Enterococcosel plate was negative. This additional testing demonstrated positive results for 7 of 14 (50%) evaluable discordant specimens which initially tested as LightCycler PCR positive but culture negative using the Enterococcosel plate containing vancomycin at 6 microg/ml and 12 of 17 (71%) evaluable discordant specimens which initially tested as LightCycler positive but culture negative using the Enterococcosel plate containing vancomycin at (8 microg/ml). These results demonstrate that the LightCycler VRE detection assay is considerably more sensitive than the standard culture method for detecting VRE directly from perianal swab specimens. The LightCycler assay also provides results much faster than culture (approximately 3.5 versus > or =72 h). The use of this test could have important implications for the effective control and prevention of nosocomial outbreaks of VRE.

Anal Canal↗

PubMed2003

Comparison of LightCycler PCR, rapid antigen immunoassay, and culture for detection of group A streptococci from throat swabs.

We compared the performance characteristics of a real-time PCR method, the LightCycler Strep-A assay (Roche Applied Science, Indianapolis, Ind.), to those of a rapid antigen immunoassay, the Directigen 1-2-3 Group A Strep Test kit (BD Diagnostic Systems, Sparks, Md.), and a standard culture method for detection of group A streptococci (GAS) from 384 throat swabs. The LightCycler PCR produced more positive results (n = 58) than either culture (n = 55) or the Directigen immunoassay (n = 31). The results of the LightCycler PCR and the Directigen method were independently compared to the results of the accepted "gold standard," bacterial culture. The sensitivities, specificities, and positive and negative predictive values for this comparison were as follows: for the Directigen method, 55, 99, 97, and 93%, respectively; for the LightCycler PCR, 93, 98, 88, and 99%, respectively. In no case was a throat swab positive by both the LightCycler PCR and the Directigen method but negative by culture. The medical histories of patients whose throat swabs were negative by culture but positive by either the LightCycler PCR (n = 7) or the Directigen method (n = 1) were reviewed. All of these patients had signs or symptoms compatible with GAS disease, and therefore, all of these discordant positive results (along with positive results by either the Directigen method or the LightCycler PCR that agreed with the culture results) were counted as true positives for statistical analysis. For this analysis, the LightCycler PCR detected more true-positive results than the culture method (58 versus 55 swabs); however, this difference was not statistically significant (P = 0.5465). In contrast, statistically significantly more true-positive results occurred by culture than by the Directigen method (55 versus 31 swabs; P < 0.0001) and by the LightCycler PCR than by the Directigen method (58 versus 31 swabs; P < 0.0001). The LightCycler PCR is a suitable stand-alone method for the detection of GAS from throat swabs. Additionally, this method requires less than half the personnel time and the procedure can be completed in considerably less time ( approximately 1 h) than our standard approach (up to 2 days) for detection of GAS in throat swabs (i.e., testing by the Directigen method with negative results verified by culture).

Cell Culture Techniques↗

PubMed2001

Prophylaxis of graft-versus-host disease with cyclosporine-prednisone is associated with increased risk of chronic graft-versus-host disease.

To determine the effect of two different graft-versus-host disease (GVHD) prophylactic regimens--cyclosporine with short course of methotrexate (CYA-MTX) and cyclosporine with prednisone (CYA-PRED)--on the incidence of chronic GVHD (cGVHD), we retrospectively reviewed the outcomes of 196 consecutive allogeneic related blood and marrow transplants performed at our institution utilizing one of these regimens. CYA-PRED was given to patients who were transplanted more recently because of concern about the increased risk of veno-occlusive disease of the liver, increased mucositis, and slower engraftment in patients receiving CYA-MTX. Prophylaxis with CYA-PRED was associated with a higher risk of development of cGVHD (risk ratio (RR) 3.5; 95% confidence intrerval (CI), 2.2-5.4). The proportion of patients with extensive disease among those developing cGVHD was higher in the CYA-PRED group (71%) than in the CYA-MTX group (57%), although this difference was not statistically significant. The cumulative probability of extensive cGVHD at 2 years was higher in the CYA-PRED group (RR 4.2, 95% CI, 2.4-7.4). Development of acute GVHD and cytomegalovirus mismatch were independent predictors of increased risk of cGVHD. We conclude that GVHD prophylaxis with CYA-PRED is associated with a higher overall rate of cGVHD compared to CYA-MTX. The type of GVHD prophylaxis should be considered when comparing the incidence of cGVHD reported in different studies.

Adolescent↗

PubMed2001

The natural history of corticosteroid therapy for inflammatory bowel disease: a population-based study.

BACKGROUND & AIMS: The aim of this study was to determine the 1-year outcome after the first course of corticosteroids in an inception cohort of patients with inflammatory bowel disease. METHODS: All patients in Olmsted County, Minnesota, diagnosed with Crohn's disease (n = 173) or ulcerative colitis (n = 185) from 1970 to 1993 who were treated with systemic corticosteroids were identified (4 denied research authorization). Immediate outcome (30 days) and 1-year outcome after the first course of corticosteroids were determined. RESULTS: Seventy-four (43%) patients with Crohn's disease and 63 (34%) with ulcerative colitis were treated with corticosteroids. Immediate outcomes for Crohn's disease were complete remission in 43 (58%), partial remission in 19 (26%), and no response in 12 (16%). Immediate outcomes for ulcerative colitis were complete remission in 34 (54%), partial remission in 19 (30%), and no response in 10 (16%). One-year outcomes for Crohn's disease were prolonged response in 24 (32%), corticosteroid dependence in 21 (28%), operation in 28 (38%), and lost to follow-up in 1 (1%). One-year outcomes for ulcerative colitis were prolonged response in 31 (49%), corticosteroid dependence in 14 (22%), and operation in 18 (29%). CONCLUSIONS: Most patients with Crohn's disease and ulcerative colitis initially respond to corticosteroids. At 1 year, 32% of patients with Crohn's disease and 48% with ulcerative colitis are corticosteroid free without operation.

Adolescent↗

PubMed2001

A prospective randomized comparison of laparoscopic appendectomy with open appendectomy: Clinical and economic analyses.

BACKGROUND: Previous randomized studies of laparoscopic appendectomy produced conflicting recommendations, and the adequacy of sample sizes is generally unknown. We compared clinical and economic outcomes after laparoscopic and open appendectomy in a sample of predetermined statistical power. METHODS: A pre-study power analysis suggested that 200 randomized patients would yield 80% power to show a mean decrease of 1.3 days' hospitalization. One hundred ninety-eight patients with a preoperative diagnosis of acute appendicitis were randomized prospectively to laparoscopic or open appendectomy. Economic analysis included billed charges, total costs, direct costs, and indirect costs associated with treatment. RESULTS: Laparoscopic appendectomy took longer to perform than open appendectomy (median, 107 vs 91 minutes; P <.01) and was associated with fewer days to return to a general diet (mean, 1.6 versus 2.3 days; P <.01), a shorter duration of parenteral analgesia (mean, 1.6 versus 2.2 days; P <.01), fewer morphine-equivalent milligrams of parenteral narcotic (median, 14 mg versus 34 mg; P =.001), a shorter postoperative hospital stay (mean, 2.6 versus 3.4 days; P <.01), and earlier return to full activity (median, 14 versus 21 days; P <.02). However, operative morbidity and time to return to work were comparable. Billed charges and direct costs were not significantly different in the 2 groups ($7711 versus $7146 and $5357 versus $4945, respectively), but total costs (including indirect costs) of laparoscopic appendectomy were, on average, nearly $2400 less, given the shorter length of stay and abbreviated recuperative period ($11,577 versus $13,965). Subgroup analyses suggested the benefit of a laparoscopic approach for uncomplicated appendicitis and for patients with active lifestyles. CONCLUSIONS: While laparoscopic appendectomy is associated with statistically significant but clinically questionable advantages over open appendectomy, a laparoscopic approach is relatively less expensive. The estimated difference in total costs of treatment (direct and indirect costs) was at least $2000 in more than 60% of the bootstrapped iterations. The economic significance and implications favoring a laparoscopic approach cannot be ignored.

Appendectomy↗

PubMed2001

Limb salvage after successful pedal bypass grafting is associated with improved long-term survival.

OBJECTIVES: Assessments of outcome after reconstruction for critical limb ischemia frequently ignore functional result and long-term morbidity and mortality. This study was undertaken to identify factors affecting long-term clinical outcome and survival after pedal bypass grafting. METHODS: The clinical data of 256 consecutive patients who underwent pedal bypass grafting for critical limb ischemia over a 12-year period were retrospectively analyzed. RESULTS: A total of 174 men and 82 women (median age, 70 years; range, 30-91 years) underwent 280 pedal bypass graft placements with autologous vein. Seventy-five percent of the patients were diabetic, and 20% had renal insufficiency (serum creatinine level > 2 mg/dL). The in-hospital mortality rate was 1.6% (4/256). The mean follow-up was 2.7 years (range, 0.1-10.1 years). Rates of primary and secondary patency, limb salvage, and survival at 5 years were 58%, 71%, 78%, 60%, respectively. A total of 160 limbs (57%) required additional interventions. Nineteen early graft thrombectomies/revisions and nine early amputations were performed. One hundred thirty-eight late interventions included 31 graft salvage procedures, 27 wound debridements, and 34 minor and 42 major amputations. At last follow-up or death, 219 (78%) limbs were being used for ambulation. End-stage renal disease (ESRD) and composite vein grafts predicted limb loss (P <.001, P <.001, respectively). Overall survival at 5 years was 60%. Survival after amputation was 79%, 53%, and 26% at 1, 3, and 5 years. Amputation and ESRD predicted higher mortality (P =.014, P =.0001, respectively). CONCLUSIONS: Pedal bypass grafting resulted in good functional limb salvage, but at the expense of multiple interventions in more than half the cases. ESRD and composite vein graft were associated with poor long-term limb salvage. Amputation after bypass grafting was associated with significantly worse long-term survival.

Adult↗

PubMed2001

Surgical reconstruction of iliofemoral veins and the inferior vena cava for nonmalignant occlusive disease.

PURPOSE: Venous reconstructions are rarely performed, and factors affecting long-term results of bypass grafts implanted in the venous system are not well defined. In this report we updated our experience. METHODS: The clinical data of all patients who underwent venous reconstruction for iliofemoral or inferior vena caval (IVC) occlusion due to nonmalignant disease between January 1985 and June 1999 were retrospectively reviewed. Patients were classified, and outcomes were compared according to the guidelines of the Joint Vascular Societies. RESULTS: Forty-two patients, 23 males and 19 females (mean age, 40 years; range, 16-81), underwent 44 venous reconstructions. Thirty-six patients had limb swelling or venous claudication, 38 had pain, and 14 had healed or active ulcers. The cause of obstruction was congenital in two and acquired in 40 (deep vein thrombosis, 25; trauma, 5; retroperitoneal fibrosis, 4; IVC occlusion devices, 4; others, 2). Eighteen patients underwent saphenous vein crossover grafts (Palma procedure), 17 had expanded polytetrafluoroethylene (ePTFE) grafts implanted (femorocaval, 8; iliocaval, 5; crossfemoral, 3; cavoatrial, 1), 6 patients had spiral vein grafts (5 iliac/femoral and 1 cavoatrial), and 1 underwent femoral vein patch angioplasty. Clinical follow-up averaged 3.5 years (median, 2.5), and graft follow-up with imaging studies averaged 2.6 years (median, 1.6). Seven patients were lost to follow-up. The secondary 3-year patency rate for all reconstructions was 62%. Palma procedures had a 4-year patency rate of 83%. The secondary patency rate of iliocaval and femorocaval ePTFE bypass grafts at 2 years was 54%. The secondary patency was lower in patients with an arteriovenous fistula (P =.023). All ePTFE grafts had a 45% patency rate at 2 years, not significantly different from saphenous vein grafts (83%, P =.16). Clinical scores improved with graft patency (median, 0.0 vs 1.5; P =.044). CONCLUSIONS: Venous reconstructions for iliofemoral or IVC obstruction offer 3-year patency rates of 62%. The Palma procedure with autologous saphenous vein had the best long-term patency, whereas long-term success with ePTFE was moderate. The use of an arteriovenous fistula to improve graft patency remains controversial.

Adolescent↗

PubMed2001

Genetic similarity in inflammatory and degenerative abdominal aortic aneurysms: a study of human leukocyte antigen class II disease risk genes.

PURPOSE: Clinically, abdominal aortic aneurysms (AAAs) display a spectrum of inflammation that extends from apparently noninflamed (degenerative) AAAs to the classic inflammatory variant. Genes encoded in the human leukocyte antigen (HLA) region are important in the development of both variants of AAA; however, their role in progression to the inflammatory variant is unknown. The purpose of this study was to compare HLA class II genes in patients with degenerative versus classic inflammatory AAAs and to quantify their impact as disease risk factors. METHODS: Genotypes of the 12 major alleles of the HLA-DR B1 locus were determined in patients with degenerative (102) and inflammatory (40) AAAs who were compared with controls (118). Univariate and multivariate logistic regression analyses were used to determine allele distributions and to quantify disease risk. RESULTS: Distribution of the HLA-DR B1 alleles was nonrandom and similar in both degenerative and inflammatory AAA groups compared with controls. The B1*02 and B1*04 alleles were enhanced in both degenerative (39.2% vs. 25.4%, P =.03; and 35.3% vs. 24.6%, P =.08 respectively) and inflammatory (47.5% vs. 25.4%, P =.01; and 32.5% vs. 24.6%, P =.09, respectively) AAAs compared with controls. The B1*02 and B1*04 alleles were associated with risk for both degenerative (odds ratio [OR] 2.2; 95% CI, 1.2-4.0; and OR 2.0; 95% CI, 1.1-3.7, respectively) and inflammatory AAAs (OR 3.7; 95% CI, 1.8-8.6; and OR 2.5; 95% CI, 1.1-6.1). CONCLUSION: This study demonstrates that identical HLA alleles function as genetic risk factors for both inflammatory and degenerative AAAs. These results support the concept of a common, immune-mediated pathogenesis for AAAs that may be modulated by HLA-independent factors.

Aged↗

PubMed2001

Ruptured abdominal aortic aneurysms: the excessive mortality rate of conventional repair.

OBJECTIVE: Rupture of abdominal aortic aneurysms (AAAs) remains lethal. In a report of patients treated in the 1980s, we recommended aggressive management. Our continued experience prompted us to reevaluate this policy. METHODS: We reviewed clinical variables affecting outcome, morbidity, mortality, and trends in mortality of all patients managed at our institution with ruptured AAAs between January 2, 1980, and November 30, 1998. RESULTS: The study group included 413 consecutive patients, 339 men and 74 women. The mean age was 74.3 years (range, 49-96); 116 (28%) patients were older than 80 years. AAA was diagnosed before rupture in 119 (29%) patients. Eighty (19%) patients had preoperative cardiac arrest. Twenty-nine (7%) patients died before operation; 65 (17%) died during the operation. The surgical mortality rate (30-day) was 37%; the overall mortality rate was 45% and was higher in women (68%) than in men (40%) (P <.001). Advanced age, APACHE (Acute Physiology and Chronic Health Evaluation) II score, initial hematocrit, and preoperative cardiac arrest were associated multivariately with 30-day mortality rates by means of stepwise logistic regression (P <.05). Twelve (23%) of 53 patients with cardiac arrest survived the operation. Logistic regression, adjusted for age, sex, and APACHE II score, demonstrated a decrease in overall and 30-day mortality rates (P <.001) over 18 years. The mean overall mortality rate was 51% from 1980 to 1984 and 42% from 1994 to 1998. CONCLUSIONS: The mortality rate of ruptured AAAs remains excessive, despite improvement over 18 years. Patients older than 80 years with shock or cardiac arrest have the highest mortality rate and should be evaluated for possible endovascular treatment. Because the diagnosis of AAA was unknown in more than 70% of patients, screening of the high-risk population and elective repair are recommended.

APACHE↗

PubMed2001

Evaluation of serologic disease markers in a population-based cohort of patients with ulcerative colitis and Crohn's disease.

BACKGROUND: The sensitivity of assays for antineutrophil cytoplasmic antibody (ANCA), anti-Saccharomyces cerevisiae antibody (ASCA), and antipancreatic antibody (PAB) in different laboratories is unknown. Likewise, the sensitivity and diagnostic usefulness of these assays in patients with inflammatory bowel disease (IBD) in the community is unknown. METHODS: An incidence cohort of 290 patients with IBD were offered participation in the study. Blood was obtained from 162 patients (56%) (83 with ulcerative colitis, 79 with Crohn's disease) who agreed to participate. ANCA was determined in five laboratories. ASCA in two laboratories, and PAB in one laboratory. RESULTS: In ulcerative colitis, the sensitivity of ANCA determined in five laboratories varied widely, ranging from 0-63%. In Crohn's disease, the sensitivity of ASCA determined in two laboratories did not vary significantly, ranging from 39-44%; and the sensitivity of PAB determined in one laboratory was 15%. The optimal diagnostic usefulness was obtained from one laboratory where the positive predictive values of a positive ANCA assay combined with a negative ASCA assay for ulcerative colitis, and a negative ANCA combined with a positive ASCA for Crohn's disease, were 75% and 86%, respectively. CONCLUSIONS: In patients with IBD, the sensitivity of ANCA varied widely in different laboratories, whereas the prevalence of ASCA was similar. The positive predictive values of the ANCA assay combined with the ASCA assay for ulcerative colitis and Crohn's disease are high enough to be clinically useful.

Adolescent↗

PubMed2001

Cigarette smoking and celiac sprue: a case-control study.

OBJECTIVE: Environmental factors other than gliadin exposure and certain HLA haplotypes may play a role in the pathogenesis of celiac disease. Previous studies have suggested a strong inverse relationship between cigarette smoking and celiac disease. We sought to determine the relationship between celiac disease and cigarette smoking in our patient population. METHODS: All newly diagnosed adults with biopsy-proven celiac disease evaluated at Mayo Clinic Rochester between January 1, 1993, and June 30, 1998, were identified. Three clinic patients who were matched to each case on geographical area of residence, age, gender, and calendar year of visit served as controls. Smoking information was obtained from a standard medical questionnaire that was completed by all clinic patients at the time of registration. The adjusted odds ratio for celiac disease in current and former smokers relative to nonsmokers was estimated with a matched three-to-one conditional logistic regression model. RESULTS: A total of 82 adults with biopsy-proven celiac disease were identified. At the time of diagnosis, the proportion of current smokers was 10% in cases and 10% in controls, yielding an adjusted odds ratio of 1.5 (95% CI = 0.5-4.3). In all, 34% of cases were former smokers versus 28% of controls, yielding an odds ratio of 1.6 (95% CI = 0.8-3.2). CONCLUSION: This case-control study was unable to detect an association between cigarette smoking and celiac disease.

Adult↗

PubMed2001

Direct identification of bacteria from positive blood cultures by amplification and sequencing of the 16S rRNA gene: evaluation of BACTEC 9240 instrument true-positive and false-positive results.

In a previous study which evaluated the BACTEC 9240 automated blood culture system (Becton Dickinson Diagnostic Instrument Systems, Sparks, Md.), we noted a 1.3% "instrument false-positive" rate. That is, the BACTEC system signaled that a bottle (BACTEC Plus Aerobic/F bottle or BACTEC Anaerobic Lytic/10 bottle) culture was positive but a Gram stain was negative and there was no growth of bacteria or yeasts on subculture to chocolate agar. Furthermore, from the same sample of blood, cultures for fungi using the Isolator blood culture system (Wampole Laboratories, Cranbury, N.J.) were negative for growth. For the present study, we evaluated 76 instrument false-positive samples for the presence of 16S ribosomal DNA using the MicroSeq 500 kit (PE Biosystems, Foster City, Calif.). These samples also were negative for fungi by the Isolator method. This kit has a PCR module and sequencing module for the amplification and sequencing of the 16S RNA gene and provides a database for sequence alignment and identification of bacteria. To optimize the assay, we evaluated the effect of adding 0.5% bovine serum albumin to the sample from blood culture bottles and found that it decreased the effects of inhibitors on the PCR. Two control groups of blood culture specimens were also evaluated. One group (n = 45) were "instrument true positives"; the instrument signaled positive, and subsequent Gram stains were positive and subcultures on chocolate agar grew bacteria. The other group (n = 20) were "instrument true negatives"; the instrument signaled negative, the Gram stain was negative, and subcultures on chocolate agar and from the Isolator tube on fungal media showed no growth. None of the 76 instrument false-positive samples had evidence for 16S rRNA gene sequences. All of the instrument true-positive samples and all of the instrument true-negative specimens were positive and negative, respectively, using the MicroSeq 500 kit. Total peripheral white blood cell counts were statistically significantly higher for patients who had instrument false-positive results than for patients who had instrument true-positive or true-negative results (P = 0.001). We conclude that instrument false positives signaled by the BACTEC 9240 system are not due to bacteria in the blood culture samples.

Bacteremia↗

PubMed2001

CT colonography: single- versus multi-detector row imaging.

PURPOSE: To compare respiratory artifacts, colonic distention, and polyp detection at computed tomographic (CT) colonography by using single- and multi-detector row helical CT systems. MATERIALS AND METHODS: A total of 237 consecutive patients received subcutaneously administered glucagon and underwent prone and supine CT colonography with single-detector row CT (n = 77) and multi-detector row CT (n = 160), followed by colonoscopy. Examination results were graded for colonic distention, respiratory artifacts, and polyp depiction by two radiologists working independently. RESULTS: Suboptimal colonic distention was significantly more common with single-detector row CT and was present in at least one segment in 52% (40 of 77 patients) of examinations versus only 19% (30 of 160 patients) with multi-detector row CT (P <.001). Mild respiratory artifacts were present in 61% (47 of 77 patients) of single-detector row CT examinations versus only 16% (26 of 160 patients) of multi-detector row CT examinations (P <.001). Depiction of polyps larger than 10 mm was 89% (eight of nine polyps) for single-detector row CT and 80% (eight of 10 polyps) for multi-detector row CT (P >.05). CONCLUSION: CT colonography performed with multi-detector row CT significantly improved the demonstration of colonic distention and depicted fewer respiratory artifacts compared with single-detector row CT. No significant differences in the depiction of polyps larger than 10 mm were demonstrated between single- and multi-detector row CT for a small number of polyps. Studies with a larger prevalence of clinically important polyps are needed for further evaluation of differences in polyp detection.

Adult↗