Adhesions and colorectal surgery - call for action

Mounting evidence highlights that adhesions are now the most frequent complication of abdominopelvic surgery, yet many surgeons are still not aware of the extent of the problem and its serious consequences. While many patients go through life without apparent problems, adhesions are the major cause of small bowel obstruction and a leading cause of infertility and chronic pelvic pain in women. Moreover, adhesions complicate future abdominal surgery with important associated morbidity and expense and a considerable risk of mortality. Studies have shown that despite advances in surgical techniques in recent years, the burden of adhesion-related complications has not changed. Adhesiolysis remains the main treatment even though adhesions reform in most patients. Recent developments in adhesion-reduction strategies and new anti-adhesion agents do, however, offer a realistic possibility of reducing the risk of adhesions forming and potentially improving the clinical outcomes for patients and reducing the associated onward burden to healthcare systems. This paper provides a synopsis of the impact and extent of the problem of adhesions with reference to the wider literature and also consideration of the key note papers presented in this special supplement to Colorectal Disease. It considers the evidence of the risk of adhesions in colorectal surgery and the opportunities and strategies for improvement. The paper acts as a 'call for action' to colorectal surgeons to make prevention of adhesions more of a priority and importantly to inform patients of the risks associated with adhesion-related complications during the consent process.

A proof-of-concept study to assess the putative dose response to topical corticosteroid in persistent allergic rhinitis using adenosine monophosphate challenge

INTRODUCTION

The aim of this proof-of-concept study was to assess whether nasal adenosine monophosphate (AMP) challenge may be used to quantify dose response to topical fluticasone propionate (FP) in persistent allergic rhinitis (PER).

METHODS

Eligible subjects with PER entered a randomized double-blind crossover study of 2 weeks of intranasal FP at 100 microg or 400 microg daily, with a 2-week placebo washout period before each randomized treatment. Measurements after each washout or treatment comprised: peak nasal inspiratory flow (PNIF) response to nasal AMP (the primary outcome), domiciliary PNIF, the mini rhinoconjunctivitis quality of life questionnaire (miniRQLQ), symptom scores, nasal nitric oxide levels and overnight urinary cortisol:creatinine ratios.

RESULTS

Thirteen patients completed per protocol. Maximal PNIF response to AMP was attenuated 0.9% (95% confidence interval -7.1 to 9.0, P=NS) by FP 100 microg, and 12.9% (4.8-20.9, P=0.009) by FP 400 microg. The 400-100 microg difference was 12.0% U (2.6-21.3, P=0.049). None of the other outcomes were responsive enough to detect any significant treatment effects. The standardized response means to FP 400 microg were 81% for AMP challenge, 54% for domiciliary PNIF, 53% for miniRQLQ, 24% for symptom scores and 18% for nasal nitric oxide. No adrenal suppression was detected at either dose.

CONCLUSION

FP exhibited dose-related suppression of nasal airway hyperresponsiveness to AMP challenge, but without associated detectable adrenal suppression at the higher dose. Moreover, the AMP response demonstrated the highest signal to noise ratio compared with other outcome measures in PER.

Individualizing the interval between neoadjuvant chemoradiation with uracil-tegafur (UFT) and total mesorectal excision in magnetic resonance imaging (MRI) defined poor-risk rectal cancer

14557

Background: The importance of achieving negative circumferential resection margins (CRM) for patients (pts) with MRI - defined poor - risk rectal cancer (PRRC) has led to an increase in the use of pre-operative chemoradiotherapy (CRT) employing long fractionation schedules, usually with an interval of 4 to 6 weeks before surgery. We report our experience of using serial MRI post CRT to optimise the timing of total mesorectal excision (TME) surgery at maximal radiological response for each pt. Methods: Data was collected prospectively from 4/03 to 10/06 on toxicity and response for 50 consecutive patients ( 36 male; median age 64 years, range 39 - 76 years), 47 with biopsy - proven PRRC by MRI criteria (threatened / definite CRM involvement, T3 > 5mm into perirectal fat, T4 tumours, and / or multiple nodes) and 3 pts with localised recurrence after previous anterior resection. Pts received 2 phase, conformal external beam radiotherapy ( 45 - 50.4 Gy / 25 - 28 fractions / 5 weeks), concurrently with their choice of either oral UFT (n = 44, 88%), 240mg/m2/d d 1 - 28 with Leucovorin (LV) 90mg/d or iv bolus 5 FU (n= 6) 300mg/m2 d 1,8,15,22,29 with LV 20 mg/m2). Clinical re-assessment q 2 wkly from 4 weeks post CRT, with serial MRIs 4-weekly, from 6 wks. Results: 48 pts (96%) completed CRT, worst toxicity, diarrhoea Grade 3, 6%. Mean number of MRI scans per pt post CRT 1.48, with response seen in 46 pts (92%), of whom 43 (86%) underwent resection, 27 (63%) of which were performed laparoscopically. Median time to surgery was 11 weeks (range 8 to 15 wks). 37pts (86% of those undergoing surgery) achieved R0 resection, mean CRM 6.1mm, mean no. of identifiable lymph nodes 6.4, most frequent pathology ypT3 pN0 26%, pCR 16%, Tmic, 21%. Surgical morbidities included small bowel adhesions requiring laparotomy 8%, infection/abscess 14%. Post-operative mortality 5%. 1 PRRC pt developed liver metastases prior to surgery. Conclusions: CRT with UFT/LV is well tolerated and effective in achieving substantial tumour regression pre-operatively for PRRC. The optimal timing of surgery post CRT at maximal response can be documented with serial MRI, resulting in a high rate of R0 resections. Laparoscopic TME is feasible in this group of pts.

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Use of geographic and genotyping tools to characterise tuberculosis transmission in Montreal

SETTING

In Canada, tuberculosis (TB) is increasingly an urban health problem. Montreal is Canada's second-largest city and the second most frequent destination for new immigrants and refugees.

OBJECTIVES

To detect spatial aggregation of cases, areas of excess incidence and local 'hot spots' of transmission in Montreal.

DESIGN

We used residential addresses to geocode active TB cases reported on the Island of Montreal in 1996-2000. After a hot spot analysis suggested two areas of overconcentration, we conducted a spatial scan, with census tracts (population 2500-8000) as the primary unit of analysis and stratification by birthplace. We linked these analyses with genotyping of all available Mycobacterium tuberculosis isolates, using IS6110-RFLP and spoligotyping.

RESULTS

We identified four areas of excess incidence among the foreign-born (incidence rate ratios 1.3-4.1, relative to the entire Island) and one such area among the Canadian-born (incidence rate ratio 2.3). There was partial overlap with the two hot spots. Genotyping indicated ongoing transmission among the foreign-born within the largest high-incidence zone. While this zone overlapped the area of high incidence among Canadian-born, genotyping largely excluded transmission between the two groups.

CONCLUSIONS

In a city with low overall incidence, spatial and molecular analyses highlighted ongoing local transmission.

Differential anti-inflammatory effects of large and small particle size inhaled corticosteroids in asthma

BACKGROUND

Extra-fine particle formulations of hydrofluoroalkane-134a beclometasone dipropionate (HFA-BDP) exhibit clinical effects comparable with conventional particle formulations of chlorofluorocarbon beclometasone dipropionate (CFC-BDP) at half the dose. There is little data comparing their effects on inflammation. We have evaluated the effects of HFA-BDP and CFC-BDP on pulmonary and systemic markers of asthmatic inflammation.

METHODS

A double-blind randomized crossover trial was undertaken comparing the anti-inflammatory effects of HFA-BDP (100 and 400 microg/day) and CFC-BDP (200 and 800 microg/day). Treatment with montelukast was evaluated as add-on to the higher dose of BDP.

RESULTS

Compared with baseline after withdrawal of usual asthma therapy, 100 microg of HFA-BDP significantly attenuated serum eosinophilic cationic protein levels (0.61-fold change, 95% CI 0.49-0.77; a 39% reduction, P < 0.001), but 200 microg of CFC-BDP did not (0.87-fold change, 95% CI 0.63-1.23; P = 1). A dose of 800 microg of CFC-BDP and 400 microg of HFA-BDP led to reductions in exhaled nitric oxide (0.57-fold change, 95% CI 0.44-0.73; a 43% reduction, P < 0.001 and 0.65-fold change, 95% CI 0.47-0.91; a 35% reduction, P = 0.008, respectively); and peripheral eosinophils (-74 cells/microl, 95% CI -146 to -2; P = 0.020 and -77 cells/microl, 95% CI -140 to -14; P = 0.012, respectively). Montelukast further reduced exhaled nitric oxide (0.81-fold change, 95% CI 0.66-0.98; P = 0.028) with 400 microg HFA-BDP and eosinophils (-44 cells/microl, 95% CI -80 to -8; P = 0.012) with 800 microg CFC-BDP, but not vice versa.

CONCLUSION

Chlorofluorocarbon beclometasone dipropionate and HFA-BDP have differential effects on pulmonary and systemic inflammation, which dictate the additive effects of montelukast.

Risk of tuberculosis infection and disease associated with work in health care settings

BACKGROUND

Tuberculosis (TB) in health care workers (HCWs) was not considered a serious problem following the advent of effective antibiotic therapy. Interest was re-stimulated by the occurrence of several major nosocomial outbreaks.

METHODS

We have reviewed the available published literature regarding prevalence and incidence of TB infection and disease among HCWs in countries categorised by mean income. We included studies published in English since 1960 from low- and middle-income countries (LMICs) and since 1990 from high-income countries (HICs). We excluded outbreak reports and studies based only on questionnaires.

RESULTS

The median prevalence of latent TB infection (LTBI) in HCWs was 63% (range 33-79%) in LMICs and 24% in HICs (4-46%). Among HCWs from LMICs, LTBI was consistently associated with markers of occupational exposure, but in HICs it was more often associated with non-occupational factors. The median annual incidence of TB infection attributable to health care work was 5.8% (range 0-11%) in LMICs and 1.1% (0.2-12%) in HICs. Rates of active TB in HCWs were consistently higher than in the general population in all countries, although findings were variable in HICs. Administrative infection control measures had a modest impact in LMICs, yet seemed the most effective in HICs.

CONCLUSIONS

TB remains a very important occupational risk for HCWs in LMICs and for workers in some institutions in HICs. Risk appears particularly high when there is increased exposure combined with inadequate infection control measures.

Combined mediator blockade or topical steroid for treating the unified allergic airway

BACKGROUND

Asthma and allergic rhinitis are manifestations of a single unified allergic airway, for which the best treatment is uncertain.

OBJECTIVE

To compare the anti-inflammatory efficacy in the unified allergic airway of combined oral mediator antagonism and combined topical steroid.

METHODS

Subjects with asthma and perennial allergic rhinitis entered a randomized double blind crossover study comparing montelukast 10 mg and cetirizine 10 mg to extra-fine inhaled beclomethasone 400 mcg/day and intranasal beclomethasone 200 mcg/day, each taken once daily for 2 months, after 2-week placebo washouts. Measurements were made after each washout and randomized treatment, comprising: methacholine PC20, exhaled and nasal nitric oxide, blood eosinophils and eosinophilic cationic protein, symptoms, lung and nasal function tests.

RESULTS

Seventeen patients completed per protocol. For PC20 and exhaled nitric oxide, only combined topical steroid produced improvements (P < 0.005) from placebo baseline. Combined steroid was superior by a 0.93 (95% CI 0.14-0.93, P < 0.05) doubling dilution difference for PC20 and a 0.99 (95% CI 0.9-15.1, P < 0.01) doubling difference for exhaled nitric oxide. Both treatments attenuated eosinophils and eosinophilic cationic protein, and reduced nasal symptoms (P < 0.05). Only steroid improved nasal nitric oxide (P=0.05) and asthma symptoms (P < 0.05). Neither treatment affected lung or nasal function tests.

CONCLUSION

Combined topical steroid and combined mediator antagonism both attenuated systemic inflammation in the unified allergic airway, but only the former reduced bronchial and nasal inflammatory markers. The relevance of this to exacerbations and airway remodelling needs to be defined.

Interferon-gamma release assays and TB screening in high-income countries: a cost-effectiveness analysis

OBJECTIVE

Interferon-gamma release assays (IGRA) are now available alternatives to tuberculin skin testing (TST) for detection of latent tuberculosis infection (LTBI). We compared the cost-effectiveness of TST and IGRA in different populations and clinical situations, and with variation of a number of parameters.

METHODS

Markov modelling was used to compare expected TB cases and costs over 20 years following screening for TB with different strategies among hypothetical cohorts of foreign-born entrants to Canada, or contacts of TB cases. The less expensive commercial IGRA, Quanti-FERON-TB Gold (QFT), was examined. Model inputs were derived from published literature.

RESULTS

For entering immigrants, screening with chest radiograph (CXR) would be the most and QFT the least cost-effective. Sequential screening with TST then QFT was more cost-effective than QFT alone in all scenarios, and more cost-effective than TST alone in selected subgroups. Among close and casual contacts, screening with TST or QFT would be cost saving; savings with TST would be greater than with QFT, except in contacts who were bacille Calmette-Guérin (BCG) vaccinated after infancy.

CONCLUSIONS

Screening for LTBI, with TST or QFT, is cost-effective only if the risk of disease is high. The most cost-effective use of QFT is to test TST-positive persons.

Laparoscopic feeding jejunostomy in esophagogastric cancer

BACKGROUND

Patients with esophagogastric malignancies often require nutritional supplementation in the perioperative period, especially in the setting where neoadjuvant therapy may delay tumor resection. A simple technique is described here that can be performed at the time of staging laparoscopy and that has not been described before.

RESULTS

Forty-three patients treated over a 4-year period who had a laparoscopic feeding jejunostomy placed at the time of staging laparoscopy were reviewed. Of these, 35 had preoperative chemotherapy according to a modified MRC OEO2 protocol. In the period between staging and eventual resection, 32% required immediate feeding, and in 14% of those who were thought not to need feeding it later became necessary. More patients gained weight or had a rise in albumin in the group that had jejunal feeding (p < 0.05). The mean time to surgery was 10 weeks. There were no conversions to an open procedure, nor were there any laparotomies for tube-related complications. Dislodgement was recorded in 6 patients; blockage, in 4. In most of these cases a simple bedside replacement of the tube was all that was required. Mean time in the operating room for each procedure was 44 minutes.

CONCLUSIONS

Laparoscopic percutaneous feeding jejunostomy is a safe and simple technique that adds little to the morbidity and cost of managing patients with esophagogastric cancers. It facilitates optimization of nutrition in the perioperative period for these patients, especially in those receiving preoperative chemotherapy.

False-positive tuberculin skin tests: what is the absolute effect of BCG and non-tuberculous mycobacteria?

BACKGROUND

Despite certain drawbacks, the tuberculin skin test (TST) remains in widespread use. Important advantages of the TST are its low cost, simplicity and interpretation based on extensive published literature. However, TST specificity is reduced by bacille Calmette-Guérin (BCG) vaccination and exposure to non-tuberculous mycobacteria (NTM).

METHODS

To estimate TST specificity, we reviewed the published literature since 1966 regarding the effect of BCG vaccination and NTM infection on TST. Studies selected included healthy subjects with documented BCG vaccination status, including age at vaccination. Studies of NTM effect had used standardised NTM antigens in healthy subjects.

RESULTS

In 24 studies involving 240,203 subjects BCG-vaccinated as infants, 20,406 (8.5%) had a TST of 10+ mm attributable to BCG, but only 56/5639 (1%) were TST-positive if tested > or =10 years after BCG. In 12 studies of 12,728 subjects vaccinated after their first birthday, 5314 (41.8%) had a false-positive TST of 10+ mm, and 191/898 (21.2%) after 10 years. Type of tuberculin test did not modify these results. In 18 studies involving 1,169,105 subjects, the absolute prevalence of false-positive TST from NTM cross-reactivity ranged from 0.1% to 2.3% in different regions.

CONCLUSIONS

The effect on TST of BCG received in infancy is minimal, especially > or =10 years after vaccination. BCG received after infancy produces more frequent, more persistent and larger TST reactions. NTM is not a clinically important cause of false-positive TST, except in populations with a high prevalence of NTM sensitisation and a very low prevalence of TB infection.

Use of icodextrin 4% solution in the prevention of adhesion formation following general surgery: from the multicentre ARIEL Registry

INTRODUCTION

Intra-abdominal adhesions occur in many patients following major abdominal surgery and represent a serious burden to patients and healthcare providers. The multicentre ARIEL (Adept Registry for Clinical Evaluation) Registry was established to gather clinical experiences in the use of icodextrin 4% solution, an approved adhesion-reduction agent, during routine general surgery.

PATIENTS AND METHODS

General surgeons from five European countries completed anonymised data collection forms for patients undergoing laparotomy or laparoscopy. Surgeons recorded patient demographics, use of icodextrin 4% solution and adverse events, and made subjective assessments of ease of use and patient acceptability with the agent.

RESULTS

The general surgery registry included 1738 patients (1469 laparotomies, 269 laparoscopies). Leakage of fluid from the surgical site did not appear to be affected by icodextrin 4% solution and was classified as 'normal' or 'less than normal' in most patients (laparotomies 86%, laparoscopies 88%). Overall, satisfaction with ease of use was rated as 'good' or 'excellent' by the majority of surgeons (laparotomies 77%, laparoscopies 86%). Patient acceptability was also good, with ratings of 'as expected' or 'less than expected' in most cases for both abdominal distension (laparotomies 90%, laparoscopies 91%) and abdominal discomfort (laparotomies 91%, laparoscopies 93%). Adverse events occurred in 30.6% of laparotomy patients and 16.7% of laparoscopy patients; the most common events were septic/infective events (4.2% and 3.4% in the laparotomy and laparoscopy groups, respectively). Anastomotic wound-healing problems were reported in 7.6% of patients in the subset of laparoscopy patients undergoing anastomotic procedures (n = 66).

DISCUSSION

Volumes of icodextrin 4% solution used as an irrigant and instillate were in line with recommendations. Surgeons considered the agent to be easy to use and acceptable to patients. The reported frequencies of adverse events were in line with those published in the literature for surgical procedures, supporting the good safety profile of this agent.

CONCLUSIONS

Icodextrin 4% solution can be used in a wide range of surgical procedures. In combination with good surgical technique, it may play an important role in adhesion reduction.

The use of environmental factors as adjuncts to traditional tuberculosis contact investigation

SETTING

A 25-year-old university student was diagnosed with cavitary pulmonary and laryngeal tuberculosis following symptoms of underlying cough of 6 months' duration.

OBJECTIVES

To estimate the hourly risk of infection (HRI) and examine the role of environmental factors, including room size and ventilation, in modulating this risk.

METHODS

Contact investigation.

RESULTS

Of 1100 contacts identified, 78.3% (n = 896) received a tuberculin skin test (TST), of whom 27.5% had a positive result. Among 634 Canadian-born contacts tested, 22.7% had a positive TST. The independent risk factors for a positive TST among Canadian-born university students were: > 35 h spent with the index case (adjusted OR 6.6, 95% CI 1.0-44.9) and smaller classroom size (aOR 5.0, 95% CI 1.4-10.0). In the first school term, the HRI among Canadian-born student contacts was 0.9%; in the second term, it was 1.6%.

CONCLUSION

There are inherent limitations in generalising findings from an outbreak investigation, due to the considerable variation in the infectiousness of cases. Nevertheless, in situations where the index case has a high degree of infectiousness, and there are numerous contacts with low expected prevalence of infection, the HRI can, together with ventilation measurements, be useful in guiding the extent of contact investigation needed.

In closely monitored patients, adherence in the first month predicts completion of therapy for latent tuberculosis infection

BACKGROUND

Current therapy for latent TB infection (LTBI) is long, and requires close follow-up. This results in sub-optimal adherence-the major reason for failure of therapy.

METHODS

In an open label randomised trial comparing 4 months of rifampicin with 9 months of isoniazid, the proportion and regularity of doses taken, measured with an electronic monitoring system (MEMS), and provider estimates of adherence in the first month of therapy, were assessed as predictors of treatment completion.

RESULTS

Of 104 patients analysed, 86 took more than 80% of doses within the expected interval, 11 took more than 80% of doses but over a longer time interval than usually allowed, and seven did not complete treatment. Treatment completion was associated with the number of doses taken, and the variability of intervals between doses during the first month of treatment.

CONCLUSIONS

Adherence in the first month, based on the number of doses and variability of times when taken, could be useful to predict completion of LTBI therapy. Interventions could be targeted to patients with suboptimal adherence in the first month.

The SCAR-3 study: 5-year adhesion-related readmission risk following lower abdominal surgical procedures

OBJECTIVE

The Surgical and Clinical Adhesions Research (SCAR) and SCAR-2 studies demonstrated that the burden of adhesions following lower abdominal surgery is considerable and appears to remain unchanged despite advances in strategies to prevent adhesions. In this study, we assessed the adhesion-related readmission risk directly associated with common lower abdominal surgical procedures, taking into account the effect of previous surgery, demography and concomitant disease.

METHODS

Data from the Scottish National Health Service medical record linkage database were used to assess the risk of an adhesion-related readmission following open lower abdominal surgery during April 1996-March 1997.

RESULTS

Patients undergoing lower abdominal surgery (excluding appendicectomy) had a 5% risk of readmission directly related to adhesions in the 5 years following surgery. Appendicectomy was associated with a lower rate of readmission (0.9%), but contributed over 7% of the total lower abdominal surgery patient readmission burden. Panproctocolectomy (15.4%), total colectomy (8.8%) and ileostomy surgery (10.6%) were associated with the highest risk of an adhesion-related readmission. Overall, the risk of readmission was doubled in patients who had undergone abdominal or pelvic surgery within 5 years of the incident operation. A higher risk of readmission was also recorded in patients aged < 60 years compared with those aged > or = 60 yrs. The effect of gender was assessed. However, as the surgical codes used were found to be skewed towards women, these data have not been reported. Readmission risk was slightly higher in patients with concomitant peritonitis compared with patients without peritonitis. In contrast, Crohn's disease had no effect on risk. Patients with colorectal cancer had a lower risk of adhesion formation. However, this may have been due to the type of surgery performed in this patient group.

CONCLUSION

The identification of high-risk patient subgroups may assist in effectively targeting adhesion-prevention strategies and the proffering of preoperative advice on adhesion risk.

Humoral response to Mycobacterium tuberculosis antigens in patients with tuberculosis in the Gambia

OBJECTIVE

To determine and compare the sensitivity and specificity of four common mycobacterial antigens with three RD-1 region antigens in the serological diagnosis of active pulmonary tuberculosis (PTB) in the Gambia.

DESIGN

Serum from 300 Gambians (100 with active PTB, 100 of their household contacts, and 100 community controls) was tested using an ELISA method to detect antibodies to seven mycobacterial antigens (three encoded in the RD-1 region [ESAT-6, CFP-10 and Rv3871] and four common [38 kDa, GLU-S, 19 kDa and 14 kDa]). Individuals with active TB were recruited from one of the National Leprosy and TB Control Program clinics in the western region of the Gambia, and neighborhood controls were an age-matched individual living within five houses of the case.

RESULTS

The sensitivity of the RD-1 antigens ranged from 34% to 67%, while specificity ranged from 51% to 71%. The sensitivity of the common antigens ranged from 24% to 75% and specificity from 26% to 75%.

CONCLUSION

In countries with high rates of TB, such as the Gambia, the clinical utility of serological testing to diagnose active TB remains limited, even with newer antigens encoded in the RD-1 region of Mycobacterium tuberculosis.

Tuberculosis surveillance among new immigrants in Montreal

SETTING

Foreign-born persons account for over 60% of Canadian tuberculosis (TB) incidence; immigrants with TB-related lung scarring ('inactive TB') are at particularly high risk, and represent an important target for preventive efforts.

OBJECTIVE

To document the performance of the immigrant surveillance programme for inactive TB in Montreal.

DESIGN

All immigrants arriving with inactive TB are referred by the public health department to the Montreal Chest Institute. We prospectively recorded clinical and radiographic data for those evaluated in 1999 and 2000. We examined physicians' adherence to Canadian guidelines. We also evaluated concordance of chest radiographic interpretation.

RESULTS

Of 1444 immigrants notified, 792 (55%) were sent referral letters. Most of the others lacked valid addresses. Of the 654 (45%) who were examined, 322 (22%) were diagnosed with untreated latent TB, 215 (15%) were recommended therapy, and 156 (11%) completed it. Of 388 potential candidates for treatment of latent TB, 274 (71%) underwent tuberculin tests. Treatment decisions followed guidelines for 87% of patients with full testing. Agreement between clinicians and chest radiologists as to TB-related radiographic abnormalities was frequent (K 0.63). Six 'high volume' clinicians performed better than others with respect to management and radiographic interpretation.

CONCLUSION

Centralised post-immigration surveillance requires more accurate referrals, and more consistent provider performance.

Latent tuberculosis infection among undergraduate medical students in Rio de Janeiro State, Brazil

SETTING

Five medical schools in three cities with different tuberculosis (TB) incidence rates in Rio de Janeiro State, Brazil.

OBJECTIVE

To estimate prevalence of and associated factors for latent tuberculosis infection (LTBI) among medical students.

DESIGN

A cross-sectional survey was conducted among undergraduate students in pre-clinical, early and late clinical years from schools in cities with low (28/100,000), intermediate (63/100,000) and high (114/100,000) TB incidence rates. Information on socio-demographic profile, previous BCG vaccination, potential TB exposure, co-morbidity and use of respiratory protective masks was obtained. A tuberculin skin test (TST) was performed using the Mantoux technique by an experienced professional. A positive TST, defined as induration > or = 10 mm, was considered LTBI.

RESULTS

LTBI prevalence was 6.9% (95%CI 5.4-8.6). In multivariate analysis, male sex (adjusted odds ratio [aOR] 1.8; 95% CI 1.1-3.0), late clinical years (aOR 1.9; 95% CI 1.01-3.5), intermediate TB incidence (aOR 4.3; 95% CI 1.3-14.6) and high TB incidence in the city of medical school (aOR 5.1; 95% CI 1.6-16.8) were significantly associated with LTBI.

CONCLUSIONS

The higher prevalence of LTBI in late clinical years suggests that medical students are at increased risk for nosocomial Mycobacterium tuberculosis infection. The implementation of a TB control program may be necessary in medical schools, particularly in cities with higher TB incidence.

Cost-effectiveness of tuberculosis control strategies among immigrants and refugees

Today, in Western Europe, Canada and the USA, more than half of all new active tuberculosis (TB) cases occur among foreign-born migrants. This article examines the impact of migration from high TB-incidence to low TB-incidence countries, and compares the cost-effectiveness of different TB control strategies. A Medline search was conducted to identify relevant English language publications prior to December 2003. Additional articles were identified from the reference lists from these publications. Despite the high proportion of active cases in low-incidence countries attributable to foreign-born residents, the public health impact is relatively low. Current chest radiograph screening programmes have little impact and are not cost-effective. Screening with sputum culture would improve cost-effectiveness marginally. Treatment of latent infection detected through screening with tuberculin skin testing or chest radiographs may require coercive measures to maximise impact and cost-effectiveness. In contrast, contact tracing, particularly within ethnic communities, appears to be more cost-efficient and less intrusive. In low-incidence countries, screening of migrants at entry has little overall impact and is not a very cost-effective tuberculosis control strategy. More effective alternatives include contact tracing delivered through primary care and increased investment in global tuberculosis control.

DOTS implementation in a middle-income country: development and evaluation of a novel approach

BACKGROUND

DOTS is widely accepted as the most cost-effective strategy for tuberculosis (TB) control. However, there is little published information regarding methods for implementation in middle-income countries.

METHODS

Over 3 years, the Canadian Lung Association assisted the Ecuadorian TB programme to implement DOTS for over half the nation's total population. A multilevel strategy developed by a team of Ecuadorian health professionals provided initial, in-service, replica and reinforcement training at the local level, and training at national level for specialist physicians, specialist societies and medical schools. Evaluation was based on international guidelines for case finding, treatment and laboratory quality control, and costs of all implementation activities.

RESULTS

By January 2004, DOTS training had been provided to 1954 health professionals and 199 smear microscopy technicians, and DOTS was implemented in all 496 health facilities. Case detection activities at the local level increased substantially. Cure and treatment completion improved to 83% of new cases. Overall concordance of laboratory quality control readings was 98.7%. The total cost of DOTS implementation was US dollar 3 049 585.

CONCLUSIONS

To achieve international targets for TB control, DOTS implementation in a middle-income country required intensive training at the local level and at multiple other levels.

Colorectal surgery: the risk and burden of adhesion-related complications

OBJECTIVES

Adhesions are associated with serious medical complications. This study examines the real-time burden of adhesion-related readmissions following colorectal surgery and assesses the impact of previous surgery on adhesion-related outcomes.

PATIENTS AND METHODS

The study used data from the Scottish National Health Service Medical Record Linkage Database to identify three cohorts of patients who had undergone open colorectal surgery during the financial years 1996-97, 1997-98 and 1998-99. Each cohort was followed up for at least 2 years and the number and category of adhesion-related readmissions was recorded. The influence of any previous operations on adhesion-related readmissions was also determined by performing a subanalysis within the 1996-97 cohort of patients who had no record of abdominal surgery within either the previous 5 or 15 years. The relative risk of adhesion-related readmissions was also assessed.

RESULTS

In the 1996-97 cohort, 9.0% of patients were readmitted within a year after surgery; 2.1% had complications directly related to adhesions and 6.9% had complications that were possibly related. After 4 years, 19.0% of patients were readmitted for reasons directly or possibly related to adhesions. Many patients were readmitted on more than one occasion and the relative risk of adhesion-related complications was 29.7 per 100 initial procedures over 4 years. In the subgroups that had no record of abdominal surgery within the previous 5 or 15 years, the relative risks of adhesion-related complications were 24.8% and 23.5%, respectively. There was no change in the rate of adhesion-related readmissions following colorectal surgery between 1996 and 1999.

CONCLUSION

Colorectal surgery is associated with a considerable rate of adhesion-related readmissions. Preventative measures should be considered to reduce this risk.

Yield of tuberculin screening among injection drug users

BACKGROUND

Regardless of their HIV status, injection drug users (IDUs) are at increased risk of developing active tuberculosis (TB) if they have latent TB infection (LTBI). We quantified the prevalence and predictors of LTBI and level of adherence to medical evaluation in a population of IDUs in Montreal.

METHODS

Participants were recruited from an ongoing dynamic cohort of IDUs followed for HIV seroconversion risk behaviour. Subjects with a tuberculin skin test (TST) of > or =5 mm were referred to designated TB clinics for medical evaluation. A financial incentive was provided for TST readings.

RESULTS

Of the 262 subjects tested, 246 (94%) returned for TST reading. The overall prevalence of positive TSTs was 22% (5% in HIV-positive, 28% in HIV-negative participants). Older age at first injection drug use (OR per 10 year increase in age 1.4, 95%CI 1.2-1.8), duration of injection drug use (OR per 10 year increase 1.6, 9.5%CI 1.5-2.2) and negative HIV status (OR 11.2, 95%CI 3.2-4.0) were independent predictors of a positive TST. Nine per cent of all TST-positive participants completed LTBI treatment.

CONCLUSION

TB screening activities with incentives can be successful in detecting TST-positive individuals, but better strategies are needed for medical follow-up in this high-risk group.