Utility of three mammalian cell entry proteins of Mycobacterium tuberculosis in the serodiagnosis of tuberculosis

SETTING

The mammalian cell entry (mce) proteins Mce3A, Mce3D and Mce3E, encoded by the mce3 operon of Mycobacterium tuberculosis, have recently been shown to be expressed during natural infection in humans.

OBJECTIVE

To determine the potential of Mce3A, Mce3D and Mce3E proteins in the serodiagnosis of tuberculosis (TB).

DESIGN

The quantitative detection of anti-Mce3A, -Mce3D and -Mce3E antibodies in serum samples from active TB patients (n = 58), healthy contacts of TB patients (n = 24) and bacilli Calmette-Guérin (BCG) vaccinated healthy subjects (n = 24) was performed using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Antibodies in serum from 98%, 86% and 90% of active TB patients and from 92%, 75% and 96% of healthy contacts of TB patients reacted with Mce3A, Mce3D and Mce3E proteins, respectively. However, none of the serum from BCG-vaccinated healthy subjects reacted with Mce3A and Mce3E proteins, and only 8% of serum samples reacted with Mce3D protein. Overall, serum from 98% active TB patients, 96% healthy contacts and 0% BCG-vaccinated healthy subjects were positive for anti-Mce3A and/or -Mce3E antibodies.

CONCLUSIONS

Our results suggest that Mce3A and Mce3E proteins may be useful for the serodiagnosis of TB infection.

Shift in the burden of cancer towards older people--a retrospective population-based study

Cancer is age-related. However, oncology and palliative medicine services focus on the needs of younger and middle-aged adults. This study examined trends in cancer deaths across age in Wales over the last 20 years. All Wales death certificates from 1981 to 2001 were examined for total and cancer deaths. Place of death and age were noted. Total deaths decreased from 35 015 in 1981 to 32 966 in 2001 while cancer deaths increased from 7369 (21.1% of all deaths) to 8292 (25.2%). Deaths due to cancer increased in the over 85 years from 9.1% to 13.1%, 75-84 years (17.1-25.2%), 65-74 years (25-35.7%), 45-64 years (33.5-40.4%) and fell from 18.3% to 16.1% in those under 44 years. Cancer deaths over 75 years increased from 33.6% of cancer deaths in 1981 to 50.1% in 2001. Cancer deaths in the community decreased from 2713 in 1981 to 2153 in 2001 and increased in hospital from 4398 to 5185 and care homes from 258 to 954. The increase in hospital cancer deaths is mainly because of 75-84 year olds (1207-1840), and the over 85 years (294-740). Half of all cancer deaths are now in those over 75 years. Cancer deaths have shifted from the community to hospital and care homes mainly because of cancer in older people. Services need to be developed to target this population.

Impact of new dialysis solutions on peritonitis rates

Peritonitis remains a major cause of morbidity among patients on peritoneal dialysis (PD), yet there is little information about the effect of new biocompatible dialysis solutions on peritonitis rates and treatment. In our unit, information on each peritonitis episode is prospectively collected. Since 2003, bicarbonate/lactate dialysate has been gradually introduced for new patients and for patients experiencing abdominal pain with conventional lactate solutions. From 2002 to 2005, data from 121 episodes of peritonitis (71 automated PD and 50 continuous ambulatory PD) were analyzed; 107 episodes occurred in patients using standard lactate dialysate and 14 episodes in patients using bicarbonate/lactate solution. Patients using bicarbonate/lactate had a significantly lower peritonitis rate of 1 per 52.5 patient-months compared to those using standard lactate dialysate (1 per 26.9 patient-months) (P=0.0179). Response to treatment, however, was not affected by the type of dialysate; cure rates (71.4 and 69.1%, respectively) and recurrence rates (21.4 and 15.8%, respectively) were not significantly different. Catheter removal was required in three (21.4%) patients using bicarbonate/lactate and 23 (22.4%) patients using lactate solution. Use of biocompatible dialysate appears to reduce the peritonitis rate by 50%, although this has to be confirmed in a randomized study. The type of dialysate, on the other hand, does not affect response to treatment.

Audit of a diabetes clinic at Tawam hospital, United Arab Emirates, 2004-2005

The aim of this audit was to determine the current management of patients with diabetes compared to international standards and to benchmark the results against current international standards. A retrospective audit of medical records of diabetic patients attending Tawam Hospital, a tertiary healthcare facility in the Al Ain region in the Emirate of Abu Dhabi, United Arab Emirates was performed. A random sample of 30 patients (5% of the target group) was selected from the total number of 600 patients who visited the diabetes clinics in August 2005. An audit form was developed based on the priority aims and measures contained in the Institute for Clinical Systems Improvement (ICSI) Guidelines for the management of type 2 diabetes mellitus. Data analysis was carried out based on measurement specifications in the ICSI Guidelines. All patients had their blood pressure checked at their most recent appointment. All except one patient had an HbA1c test and a lipid profile performed during the study period. Although 75% of patients were referred for a dilated eye examination, only 47% complied. Approximately two-thirds of all patients had evidence of self-monitoring of blood glucose. Less than half of the patients were referred to the nutritionist and only a relatively small proportion of patients had advice on diet and exercise documented in their medical record. There was also lack of documentation, particularly for smoking status, foot examination, and body mass index (BMI). All patients received aspirin (ASA) treatment. The majority had a systolic blood pressure of 130 mmHg or less; just under half of patients had HbA1c of less than 7%. In comparison to the Center for Diseases Control (CDC) targets, we exceeded targets in three areas in relation to HbA1c testing, ASA treatment, and self-report monitoring blood glucose. We did not meet the stated target of 75% for patients having a dilated eye exam due to lack of patient compliance (more than three-quarters of all patients were referred but did not attend for appointment). Documentation of a comprehensive foot examination was present for only one-quarter of all patients compared to the recommended target of three-quarters of patients. Documentation of advice on diet and exercise was present for 40%, which did not meet the CDC target of 60%. Overall, the audit highlighted that Tawam Hospital is providing a good level of care to diabetic patients and compares favorably with international targets; however, key recommended actions have been identified for implementation to improve patient care and maintain a continuous improvement process through effective monitoring with prioritization to those related to preventative care.

Frequency of embB codon 306 mutations in ethambutol-susceptible and -resistant clinical Mycobacterium tuberculosis isolates in Kuwait

SETTING

Recent reports of embB306 mutations in ethambutol-resistant and ethambutol-susceptible drug-resistant strains of Mycobacterium tuberculosis have questioned the significance of these mutations in conferring resistance to ethambutol (EMB).

OBJECTIVE

To determine the occurrence of embB306 mutations in all EMB-resistant and -susceptible drug-resistant M. tuberculosis strains isolated during a specified period at a single geographical location.

DESIGN

Twenty-five pansusceptible, all EMB-resistant and -susceptible M. tuberculosis strains resistant to other first-line drugs isolated in Kuwait during 2000-2003 were analyzed. The embB306 mutations were detected by PCR-restriction fragment length polymorphism and DNA sequencing. The PCR-based methods were also used for determining strain relatedness.

RESULTS

None of the pansusceptible M. tuberculosis strains contained a mutation at embB306. Fifteen of 50 (30%) EMB-resistant strains but only three of 122 (2%) EMB-susceptible isolates resistant to other first-line drugs contained a mutated embB306. The EMB-susceptible isolates with embB306 mutation were resistant to isoniazid plus other drug(s). The isolates carrying similar mutations were genotypically distinct strains.

CONCLUSIONS

The frequency of embB306 mutations in EMB-resistant strains compared to EMB-susceptible M. tuberculosis isolates resistant to other drugs was 15 times higher. Association of embB306 mutations in EMB-susceptible strains with isoniazid resistance and inherent problems associated with phenotypic EMB susceptibility testing suggest that these strains may actually be EMB-resistant.

Effect of immersion disinfection with Perform-ID on alginate, an alginate alternative, an addition-cured silicone and resultant type III gypsum casts

OBJECTIVE

This study investigated the effect of a commonly used immersion disinfectant upon three different impression materials and any subsequent effects on the abrasion resistance, hardness and surface detail reproduction of gypsum casts.

DESIGN

A laboratory study.

MATERIALS AND METHODS

Under standardised conditions a total of 120 impressions were made of a ruled test block using irreversible hydrocolloid (Alginoplast), an 'alginate alternative' addition-cure silicone (Position Penta) and a conventional addition-cure silicone (President). The impressions were examined for surface detail reproduction prior to and after disinfection with Perform-ID. The type III casts were evaluated for surface detail reproduction, surface hardness and abrasion resistance.

RESULTS

(1) None of the disinfected alginate specimens could reproduce the 50 microm line. (2) Casts produced from the disinfected alginate were significantly less hard than from disinfected Position Penta and President (P <0.001). (3) Disinfection significantly affected the abrasion resistance of casts made from Position Penta (P = 0.029). (4) Disinfection did not significantly affect President or its subsequent casts (P >0.05).

CONCLUSION

If disinfecting with Perform-ID, the impression should be made with a conventional addition-cured silicone if good surface detail reproduction of the impression material and a hard and abrasion resistant type III gypsum cast are required.

Cardiac output monitoring in intensive care patients by radial artery pressure waveform analysis

We have developed a novel technique for monitoring cardiac output (CO) changes by mathematically analyzing a single peripheral arterial blood pressure (ABP) waveform. In contrast to all previous techniques, our technique analyzes the ABP waveform over time scales greater than a cardiac cycle in which complex wave reflections are attenuated. We have previously validated the technique in swine instrumented with aortic flow probes. We present here an initial evaluation of the technique in 16 patient records of the MIMIC (Multi-parameter Intelligent Monitoring for Intensive Care) database, consisting of 122 simultaneous pairs of radial ABP waveforms and thermodilution CO. We report an overall error in the technique of 18.1% with respect to the error-prone clinical thermodilution measurements. This study promotes thorough future testing of the technique in humans.

Estimating injury severity using the Barell matrix

OBJECTIVE

To determine whether the Barell matrix (Inj Prev 2002;8:91-6) could effectively categorize injuries by severity.

METHODS

Injury diagnoses of cases in the 2002 US Nationwide Inpatient Sample were classified according to the Barell matrix. For each cell of the matrix, the authors used ICDMAP-90 to determine the predominant Abbreviated Injury Score (AIS) and body region, and calculated the weighted proportion surviving (bPScell) among patients with any diagnosis in that cell. These findings were used to estimate maximum AIS (bAISmax), ISS (bISS), and the minimum or product of bPScell (bPSmin, bPSprod) for injured patients in the 1996-2000 US National Hospital Discharge Surveys. Case survival was determined for different scores, and outcome models using age, sex, comorbidity, mechanism, and bISS or bPSmin were compared to models using ISS calculated from ICDMAP-90 (mISS) or using ICISS.

RESULTS

Case survival decreased with increasing bAISmax or bISS; survival was closely approximated by bPSmin, and also increased monotonically with bPSprod. Outcome models using bISS or bPSmin were similar to those using mISS or ICISS. An Abbreviated Barell Categorization, with only four groups, was also effective.

CONCLUSION

Barell matrix categorization of administrative data allows severity scoring similar to that obtainable with ICDMAP-90 or ICISS.

Catheter-associated fungemia due to Exophiala oligosperma in a leukemic child and review of fungemia cases caused by Exophiala species

A case of catheter-associated fungemia due to Exophiala oligosperma in a 3-year-old leukemic child is presented. The etiologic agent was isolated from blood specimens and the catheter tip. The isolate was identified by its morphological characteristics and DNA sequencing of the internal transcribed spacer region of rDNA. Despite initial amphotericin B and itraconazole therapy, the child's fever subsided only after removal of the catheter. A review of the medical literature revealed 29 cases of infection due to Exophiala species. Twenty-three of these 29 patients had a CVC in place when they developed fever or other manifestations of fungemia. Withdrawal of the CVC together with amphotericin B and/or itraconazole therapy generally resulted in a good prognosis.

MRI-based measurements of respiratory motion variability and assessment of imaging strategies for radiotherapy planning

Respiratory organ motion has a significant impact on the planning and delivery of radiotherapy (RT) treatment for lung cancer. Currently widespread techniques, such as 4D-computed tomography (4DCT), cannot be used to measure variability of this motion from one cycle to the next. In this paper, we describe the use of fast magnetic resonance imaging (MRI) techniques to investigate the intra- and inter-cycle reproducibility of respiratory motion and also to estimate the level of errors that may be introduced into treatment delivery by using various breath-hold imaging strategies during lung RT planning. A reference model of respiratory motion is formed to enable comparison of different breathing cycles at any arbitrary position in the respiratory cycle. This is constructed by using free-breathing images from the inhale phase of a single breathing cycle, then co-registering the images, and thereby tracking landmarks. This reference model is then compared to alternative models constructed from images acquired during the exhale phase of the same cycle and the inhale phase of a subsequent cycle, to assess intra- and inter-cycle variability ('hysteresis' and 'reproducibility') of organ motion. The reference model is also compared to a series of models formed from breath-hold data at exhale and inhale. Evaluation of these models is carried out on data from ten healthy volunteers and five lung cancer patients. Free-breathing models show good levels of intra- and inter-cycle reproducibility across the tidal breathing range. Mean intra-cycle errors in the position of organ surface landmarks of 1.5(1.4)-3.5(3.3) mm for volunteers and 2.8(1.8)-5.2(5.2) mm for patients. Equivalent measures of inter-cycle variability across this range are 1.7(1.0)-3.9(3.3) mm for volunteers and 2.8(1.8)-3.3(2.2) mm for patients. As expected, models based on breath-hold sequences do not represent normal tidal motion as well as those based on free-breathing data, with mean errors of 4.4(2.2)-7.7(3.9) mm for volunteers and 10.1(6.1)-12.5(6.3) mm for patients. Errors are generally larger still when using a single breath-hold image at either exhale or inhale to represent the lung. This indicates that account should be taken of intra- and inter-cycle respiratory motion variability and that breath-hold-based methods of obtaining data for RT planning may potentially introduce large errors. This approach to analysis of motion and variability has potential to inform decisions about treatment margins and optimize RT planning.

Neck dissection following organ preservation protocols prolongs feeding tube dependence in patients with advanced head and neck cancer

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Background: Organ preserving strategies employed in the treatment of advanced stage head and neck cancer frequently result in significant organ dysfunction including dysphagia and feeding tube dependence. While the acute and chronic effects of radiation and chemotherapy are known to contribute to swallowing impairment, the effect of a neck dissection, performed 6–8 weeks following the completion of treatment is unknown. Methods: Retrospective review of Stage III/IV squamous carcinoma patients treated with primary radiation with/without chemotherapy and a post-treatment neck dissection, who remain free of locoregional or distant failure for a minimum of two years. Predictors of prolonged feeding tube dependence (>24 months following the completion of treatment) were evaluated using univariate and multivariate analysis. To determine the independent effect of neck dissection on length of feeding tube dependence, patients matched for covariates were also compared. Results: 79 patients treated at the Fox Chase Cancer Center between 1992 to 2003 were included in this study. 61 (77.2%) received chemotherapy and 37 (46.8%) underwent a neck dissection. The surgical specimen was positive for residual carcinoma in 12 patients (33%). 57 patients (71.3%) underwent placement of a feeding tube. The median time to removal of feeding tubes was 12 months [7–17 months, 95% CI]. Feeding tube-free status at 24 months was associated with use of standard radiotherapy (p = 0.031), N0 vs N+ neck stage (p = 0.041) and management without a neck dissection (p = 0.003). There was no association with age, T-stage, tumor site or use of chemotherapy. On multiple regression, only neck dissection remained a predictor of retained feeding tube at 24 months (p = 0.013). In patients matched for N-stage and treatment selection, those who underwent a neck dissections required a feeding tube a median of 36 months compared with 10 months for those without a neck dissection [32–57 months versus 7–13 months, 95% CI, p = 0.021]. The two year frequency of feeding tube dependence was 14/34 (41%) versus 3/30 (10%), respectively (p = 0.005). Conclusions: Neck dissection may contribute dysphagia experienced by head and neck cancer patients treated with organ preservation protocols.

No significant financial relationships to disclose.

An experience of emergency ultrasonography in children in a sub-Saharan setting

Emergency ultrasonography is an appealing imaging modality in paediatric emergencies, given its non-invasive nature and potential as an adjunct to physical examination in a setting where rapid decisions need to be made. This review of a case series describes the applications, versatility, and limitations of emergency physician led ultrasonography in a paediatric resuscitation room in a sub-Saharan African setting.

Detection of coins ingested by children using a handheld metal detector: a systematic review

To determine if the use of a handheld metal detector (HHMD) can safely reduce the number of radiographs requested in cases of coins ingested by children, a search was performed to identify prospective studies of the ability of an HHMD to identify the presence or absence of ingested coin in children (17 years or younger). Outcome measures were presence or absence of coin on metal detector screening, and accuracy of coin localisation. Inclusion and exclusion criteria were defined. Mantel-Haenszel (fixed effect model) pooling with 95% confidence intervals (CI) was used to calculate overall sensitivities and specificities. In total, 11 studies met the inclusion criteria. The overall sensitivity of the HHMD at detecting the presence of coins was 99.4% (95% CI 98.0 to 99.9%) and accuracy at localisation was 99.8% (98.5 to 100.0%). The overall specificity of the HHMD was 100% (76.8 to 100%). Use of the HHMD is an accurate, radiation free, and cost effective method of identifying and localising coins ingested by children. An algorithm for investigating children with coin ingestion is proposed.