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.

Sensitivity of a whole-blood interferon-gamma assay among patients with pulmonary tuberculosis and variations in T-cell responses during anti-tuberculosis treatment

BACKGROUND

Interferon-gamma (IFN-gamma) assays are new tests for tuberculosis (TB) infection, and T-cell responses may be correlated with antigen burden. However, it is unclear if IFN-gamma assays can be used to monitor response to TB treatment.

MATERIALS AND METHODS

We measured T-cell responses to TB specific antigens in 60 Indian patients with microbiologically confirmed active pulmonary tuberculosis, before, during, and after TB treatment. Most patients were hospitalized and had moderate to advanced disease. IFN-gamma responses were measured using the commercial whole-blood Quanti-FERON-TB Gold In Tube (QFT-G) assay at three time-points: at diagnosis (N = 60), after 2 months of intensive treatment (N = 47), and at 6 months (treatment completion) (N = 39).

RESULTS

At baseline, 44 of 60 (73%) patients were positive by QFT-G. At the second time-point, 38 of 47 (81%) patients were positive. At treatment completion, 31 of 39 (79%) patients were positive. Changes in IFN-gamma responses over time were highly inconsistent--some individuals showed increases, while others showed decreases or no changes. Although the average IFN-gamma levels decreased slightly during treatment (not significant), the QFT-G sensitivity remained mostly unchanged during therapy.

CONCLUSIONS

Our data suggest that the QFT-G assay has modest sensitivity in patients with moderate to advanced pulmonary disease, but our results do not show a clear correlation between antigen burden and T-cell responses. Further research is needed to understand the kinetics of T-cell responses during TB treatment.

Yield of serial sputum specimen examinations in the diagnosis of pulmonary tuberculosis: a systematic review

Current international tuberculosis (TB) guidelines recommend the microscopic examination of three sputum specimens for acid-fast bacilli in the evaluation of persons suspected of having pulmonary TB. We conducted a systematic review of studies that quantified the diagnostic yield of each of three sputum specimens. By searching multiple databases and sources, we identified a total of 37 eligible studies. The incremental yield in smear-positive results (in studies using all smear-positive cases as the denominator) and the increase in sensitivity (in studies that used all culture-positive cases as the denominator) of the third specimen were the main outcomes of interest. Although heterogeneity in study methods and results presented challenges for data synthesis, subgroup analyses suggest that the average incremental yield and/or the increase in sensitivity of examining a third specimen ranged between 2% and 5%. Reducing the recommended number of specimens examined from three to two (particularly to two specimens collected on the same day) could benefit TB control programs, and potentially increase case detection for several reasons. A number of operational research issues need to be addressed. Studies examining the most effective and efficient means to utilize current technologies for microscopic examination of sputum would be most useful if they followed an internationally coordinated and standardized approach, both to strengthen the country-specific evidence base and to permit comparison among studies.

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.

Tailored prophylaxis in severe hemophilia A: interim results from the first 5 years of the Canadian Hemophilia Primary Prophylaxis Study

BACKGROUND

Prophylactic treatment for severe hemophilia A is likely to be more effective than treatment when bleeding occurs, however, prophylaxis is costly. We studied an inception cohort of 25 boys using a tailored prophylaxis approach to see if clotting factor use could be reduced with acceptable outcomes.

METHODS

Ten Canadian centers enrolled subjects in this 5-year study. Children were followed every 3 months at a comprehensive care hemophilia clinic. They were initially treated with once-weekly clotting factor; the frequency was escalated in a stepwise fashion if unacceptable bleeding occurred. Bleeding frequency, target joint development, physiotherapy and radiographic outcomes, as well as resource utilization, were determined prospectively.

RESULTS

The median follow-up time was 4.1 years (total 96.9 person-years). The median time to escalate to twice-weekly therapy was 3.42 years (lower 95% confidence limit 2.05 years). Nine subjects developed target joints at a rate of 0.09 per person-year. There was an average of 1.2 joint bleeds per person-year. The cohort consumed on average 3656 IU kg(-1)year(-1) of factor (F) VIII. Ten subjects required central venous catheters (three while on study); no complications of these devices were seen. One subject developed a transient FVIII inhibitor. End-of-study joint examination scores--both clinically and radiographically--were normal or near-normal.

CONCLUSIONS

Most boys with severe hemophilia A will probably have little bleeding and good joint function with tailored prophylaxis, while infusing less FVIII than usually required for traditional prophylaxis.

Diagnosis of myocardial contusion after blunt chest trauma using18F-FDG positron emission tomography

Cardiac contusion is an infrequent complication of blunt chest trauma. The definite diagnosis of myocardial contusion is complex and needs a number of examinations such as electrocardiography, echocardiography, cardiac enzyme and radionuclide perfusion scan. We present a patient who had a blunt chest trauma from a car accident resulting in an acute myocardial infarction without injury to coronary arteries. The non-viable myocardium was diagnosed with (18)F-fluorodeoxyglucose positron emission tomography (FDG PET) combined with (201)Tl perfusion single photon emission tomography (SPECT). This is the first report of FDG PET for the diagnosis of myocardial contusion in blunt myocardial trauma.

Canadian multi-institutional survey of immune tolerance therapy (ITT) - experience with the use of recombinant factor VIII for ITT

Immune tolerance therapy (ITT) is currently the most effective approach to eradicate inhibitors in patients with haemophilia A. Limited evidence suggests that the use of plasma-derived factor VIII (pdFVIII) for ITT may be associated with a greater success rate than recombinant factor VIII (rFVIII). Analysis of ITT cases in Canada offered the opportunity to examine the success rate of using rFVIII for ITT, as rFVIII has been used almost exclusively for Canadian haemophilia A patients since 1994. The results of 32 patients from five haemophilia treatment centres were collated. Three patients continue on ITT. Of the 29 patients who completed ITT, 25 (86.2%) used rFVIII exclusively, and four used pdFVIII exclusively or pdFVIII followed by rFVIII. The initial FVIII dosing frequency was once per day in 72.4% of patients at an average dose of 98 U kg(-1) (range 50-200). Eight patients (25%) received one or more adjuvant therapies. The median duration of ITT was 1.1 years (mean 1.5 years, range 9 days to 6 years). The overall success rate of the 29 patients who completed ITT was 79.3% (23/29), which is comparable with the results of immune tolerance registries. Our results suggest that the success rate of ITT using rFVIII is not inferior to the results with pdFVIII.

Alternatives to the tuberculin skin test: interferon-gamma assays in the diagnosis of mycobacterium tuberculosis infection

For nearly a century, there were no alternatives to the tuberculin skin test (TST) for diagnosing latent tuberculosis infection. Because of advances in immunology and genomics, for the first time, an alternative has emerged in the form of T cell based interferon-g (IFN-gamma) assays, a new generation of in vitro tests of cellular immunity. These assays measure cell mediated immune response by quantifying IFN-gamma released by T cells in response to stimulation by Mycobacterium tuberculosis antigens. Although early versions of IFN-gamma assays used purified protein derivative (PPD) as the stimulating antigen, newer versions use antigens that are significantly more specific to M. tuberculosis. These specific antigens include ESAT-6 and CFP-10. These proteins, encoded by genes located within the region of difference 1 (RD1) segment of the M. tuberculosis genome, are more specific to M. tuberculosis than PPD because they are not shared with any BCG substrains or several nontuberculous mycobacterial species. A review of current evidence on the performance of IFN-gamma assays and TST suggests that both the TST and IFN-gamma assays have advantages and limitations, and both tests appear to be useful at this time. The emergence of IFN-gamma assays is a much anticipated, welcome development that has, for the first time, increased the choice of tests available for diagnosing latent tuberculosis infection. Because both tests have their strengths and limitations, the decision to select one over the other will depend on the population, the goal of testing, and the resources available. To fully evaluate the utility of IFN-gamma assays in high burden countries such as India, long-term cohort studies are needed to determine the association between positive IFN-gamma results and the subsequent risk of active disease.

Inhibition of in-stent restenosis in rabbit iliac arteries with photodynamic therapy

OBJECTIVES

Photodynamic therapy (PDT, the combination of light with a photosensitising drug in the presence of oxygen) inhibits restenosis after angioplasty without stenting. This study assesses the potential of PDT for prevention of in-stent re-stenosis.

DESIGN AND METHODS

Normal rabbits were given the photosensitising agent 5-aminolaevulinic acid (ALA) 60 mg/kg, 3 h prior to endovascular illumination of the iliac artery (635 nm at 50 J/cm(2)) either immediately before or after deployment of an oversized (3 mm diameter) stent. PDT treated arteries were retrieved 3 or 28 days later and assessed for cell counts and vascular morphometry. Control arteries (stent but no PDT) were examined at 28 days.

RESULTS

There were no adverse events and all vessels were patent at the end of the study. At 3 days there was almost complete medial cell ablation when light was delivered before stent deployment (17+/-1 cells/hpf), with little effect when illumination followed stent deployment (184+/-17 cells/hpf, p<0.0001). Twenty-eight days after PDT, the neointimal areas were 1.41+/-0.52 mm(2) (stent with no PDT), 1.24+/-0.54 mm(2) (light after stent) and 0.60+/-0.21 mm(2) (light before stent) (p=0.004).

CONCLUSIONS

PDT before stent deployment caused almost complete medial cell ablation at 3 days with inhibition of in-stent restenosis at 28 days. PDT is worthy of further study as an adjuvant to percutaneous intervention in patients with vascular disease.

Comparing hand-held computers and paper diaries for haemophilia home therapy: a randomized trial

Treatment of severe haemophilia with factor concentrates is by self-infusion in the home. Adherence to record keeping on paper diaries is poor. A randomized-controlled trial compared adherence with record keeping of paper diaries with hand-held computers. Forty-one individuals with severe haemophilia, were randomized to hand-held computers (n = 22) or paper diaries (n = 19) and followed for 6 months. About 86.2% (679 of 788) of infusions by patients in the computer group were in compliance with the data submission schedule compared with only 48.3% (358 of 741) of infusions by patients using paper diaries (P < 0.0001). The time intervals between infusions and the receipt of data were shorter in the computer group (median 0.25 vs. 25 days respectively, P < 0.0001). Reminder phone calls by the clinic were made less frequently to users of hand-held computers than to users of paper diaries (median one vs. five times, P < 0.0001). Accuracy of data was similar for both methods. Compliance with hand-held computers was superior to paper diaries. The clinic received data from hand-held computers mostly on the same day, and nurses could thereby provide clinical advice more effectively. Although hand-held computers did not result in increased accuracy, errors could be detected and corrected more rapidly. Electronic data can more easily be verified, analysed and summarized than that from paper diaries.

Accuracy of physical examination in the diagnosis of hypothyroidism: a cross-sectional, double-blind study

BACKGROUND

Hypothyroidism is a common, potentially treatable endocrine disorder. Since hypothyroidism is not always associated with the signs and symptoms typically attributed to it, the diagnosis is often missed. Conversely, patients with typical signs and symptoms may not have the disease when laboratory tests are performed.

AIMS

We aimed to determine the accuracy of physical examination in the diagnosis of hypothyroidism.

SETTING AND DESIGN

Prospective, hospital-based, cross-sectional diagnostic study.

MATERIAL AND METHODS

Consecutive outpatients from the medicine department were screened and an independent comparison of physical signs (coarse skin, puffy face, slow movements, bradycardia, pretibial oedema and ankle reflex) against thyroid hormone assay (TSH and FT4) was performed.

STATISTICAL ANALYSIS

Diagnostic accuracy was measured as sensitivity, specificity, positive likelihood ratios, negative likelihood ratios and positive and negative predictive values.

RESULTS

Of the 1450 patients screened, 130 patients (102 women and 28 men) underwent both clinical examination and thyroid function tests. Twenty-three patients (18%) were diagnosed to have hypothyroidism by thyroid hormone assays. No single sign could easily discriminate a euthyroid from a hypothyroid patient (range of positive likelihood ratio (LR+) 1.0 to 3.88; range of negative likelihood ratio (LR-): 0.42 to 1.0). No physical sign generated a likelihood ratio large enough to increase the post-test probability significantly. The combination of signs that had the highest likelihood ratios (coarse skin, bradycardia and delayed ankle reflex) was associated with modest accuracy (LR+ 3.75; LR- 0.48).

CONCLUSION

Clinicians cannot rely exclusively on physical examination to confirm or rule out hypothyroidism. Patients with suspected hypothyroidism require a diagnostic workup that includes thyroid hormone assays.

Primary squamous cell carcinoma of caecum

Proximal to the anal canal, carcinomas composed in whole or in part of squamous epithelium are distinctly uncommon, accounting for 0.1 per cent of all colorectal carcinomas. Pure squamous cell carcinoma of the colorectum are extremely rare. Here we report a case of primary squamous cell carcinoma of the caecum in a 55 year old lady from South India.

Serum leptin in disabled and non-disabled children in an Indian slum population

OBJECTIVE

To assess the concentration of serum leptin in a population of malnourished children and to compare the leptin levels of disabled and non-disabled children in this population.

DESIGN

Case-control study.

SUBJECTS

Eighty-one children, comprising 41 children with mixed disabilities and 40 non-disabled controls, were selected from 425 children involved in a case-control study assessing the nutritional status of children with disabilities in an Indian slum population.

METHODS

Leptin was measured in the serum samples and was compared with anthropometry (weight-for-age Z-scores (WAZ), height-for-age Z-scores (HAZ), weight-for-height Z-scores (WHZ), body mass index (BMI), mid-upper-arm circumference (MUAC), sub-scapular skinfold thickness and triceps skinfold thickness) and serum acute phase proteins.

RESULTS

The children were very malnourished with WAZ=-2.07 (s.d. 1.15), HAZ=-2.15 (s.d. 1.85) and WHZ=-1.07 (s.d. 0.83). Leptin was extremely low in both the disabled (1.44 ng/ml; 95% confidence interval, CI, 1.23-1.69) and the non-disabled (1.19 ng/ml; 95% CI 1.04-1.35) children. There were no differences between the disabled and non-disabled groups as a whole but 15 children with neurological disabilities had significantly higher (P<0.05) serum leptin (1.65 ng/ml; 95% CI 1.29-2.06) than the non-disabled children. Girls (1.55 ng/ml; 95% CI 1.29-1.87) had significantly higher concentrations of leptin than boys (1.11 ng/ml; 95% CI 1.02-1.22; P=0.002). Leptin did not correlate with any biochemical or anthropometric measures.

CONCLUSIONS

In this population, where malnutrition was common, serum leptin levels were very low and did not correlate with anthropometry.

SPONSORSHIP

UK Department for International Development; Virgin Airways through the Great Ormond Street Hospital Trustees.

Adequate vascular training opportunities can be provided without compromising patient care

OBJECTIVES

to review the results of index operations in vascular surgery and to evaluate the impact of a specialist vascular training programme on patient outcome.

METHODS

we undertook a 5-year (January 1995-December 1999) review of the weekly-collected mortality and morbidity data. The total number, 30-day mortality and stroke rate of all index operations i.e. AAA repairs (ruptured and elective), carotid operations and infra-inguinal bypasses (above and below knee, elective and emergency) was recorded. The number of operations performed by trainees under supervision was recorded.

RESULTS

in the 5-year period 991 index operation were done of which 738 (74%) were done by trainees. Operations done by trainees were supervised by a consultant in 82% of cases with no significant effect on death or stroke rates. Overall vascular trainees performed 75% of the index operations of which 82% were supervised.

CONCLUSIONS

trainees under supervision performed three out of four index operations. The mortality and morbidity of index operations in our unit compared well with accepted best mortality and morbidity figures. Our unit provides good training opportunities for vascular trainees whilst maintaining satisfactory standards of patient care.

Platelets from patients with the Quebec platelet disorder contain and secrete abnormal amounts of urokinase-type plasminogen activator

The Quebec platelet disorder (QPD) is an autosomal dominant platelet disorder associated with delayed bleeding and alpha-granule protein degradation. The degradation of alpha-granule, but not plasma, fibrinogen in patients with the QPD led to the investigation of their platelets for a protease defect. Unlike normal platelets, QPD platelets contained large amounts of fibrinolytic serine proteases that had properties of plasminogen activators. Western blot analysis, zymography, and immunodepletion experiments indicated this was because QPD platelets contained large amounts of urokinase-type plasminogen activator (u-PA) within a secretory compartment. u-PA antigen was not increased in all QPD plasmas, whereas it was increased more than 100-fold in QPD platelets (P <.00009), which contained increased u-PA messenger RNA. Although QPD platelets contained 2-fold more plasminogen activator inhibitor 1 (PAI-1) (P <.0008) and 100-fold greater u-PA-PAI-1 complexes (P <.0002) than normal platelets, they contained excess u-PA activity, predominantly in the form of two chain (tcu-PA), which required additional PAI-1 for full inhibition. There was associated proteolysis of plasminogen in QPD platelets, to forms that comigrated with plasmin. When similar amounts of tcu-PA were incubated with normal platelet secretory proteins, many alpha-granule proteins were proteolyzed to forms that resembled degraded QPD platelet proteins. These data implicate u-PA in the pathogenesis of alpha-granule protein degradation in the QPD. Although patients with the QPD have normal to increased u-PA levels in their plasma, without evidence of systemic fibrinogenolysis, their increased platelet u-PA could contribute to bleeding by accelerating fibrinolysis within the hemostatic plug. QPD is the only inherited bleeding disorder in humans known to be associated with increased u-PA.

Pre-hospital delay in acute myocardial infarction in an urban Indian hospital: a prospective study

BACKGROUND

Successful treatment of acute myocardial infarction is dependent on early presentation of the patient to the hospital. The factors that contribute to delay in seeking treatment have not been systematically evaluated in the Indian milieu.

METHODS

Patients admitted with acute myocardial infarction to a 125-bed urban community hospital were evaluated prospectively. A record of admission characteristics, prior medical history, pre-hospital symptoms and treatment patterns was completed within 48 hours of each admission. Independent predictors of delayed admission were identified by logistic regression.

RESULTS

Of 144 consecutive admissions with myocardial infarction, 133 had completed data as per the protocol [mean (SD) age 59 (12.7) years; 79.6% men]. The distribution of presentation times was skewed, with the mode, median and mean being 1, 3 (interquartile range 1.25-11) and 10.9 (SD 20.5) hours, respectively. Seventy-nine patients (59.4%) consulted a general practitioner prior to hospital referral and 48 patients (36.1%) delayed admission to hospital by more than 6 hours from the onset of symptoms. On multivariate analysis, individuals who were initially seen by a general practitioner (OR 5.57; 95% CI 1.84-16.8) and those over the age of 65 years (OR 3.24; 95% CI 1.06-9.89) were identified as 'delayers', while patients with severe symptoms (OR 0.32; 95% CI 0.12-0.87) or prodromal angina (OR 0.25; 95% CI 0.08-0.82) minimized delay.

CONCLUSION

Though 50% of patients with acute myocardial infarction present to hospital within 3 hours, about 36% delay seeking treatment by more than 6 hours. Besides age and the pattern and severity of symptoms, visits to the general practitioner were found to be an independent correlate of delay.

Imaging of malignant lymphomas with F-18 FDG coincidence detection positron emission tomography

PURPOSE

The authors evaluated the utility of F-18 fluorodeoxyglucose (FDG) coincidence detection (CoDe) positron emission tomography (PET) for staging, post-treatment evaluation, and follow-up assessment of patients with malignant lymphomas.

MATERIALS AND METHODS

Fifty-eight patients with histologically proved malignant lymphomas (4 Hodgkin's disease, 54 non-Hodgkin's lymphoma) underwent CoDe PET using F-18 FDG. CoDe PET was performed using a dual-head gamma camera equipped with coincidence detection circuitry. Of the 87 CoDe PET studies, 26 were performed for staging, 38 for post-treatment evaluation, and 23 for follow-up evaluation of recurrence. The entire trunk, from the cervical to the inguinal regions, or selected regions were scanned with the patient in the supine position. No attenuation correction was made and reconstruction was performed using filtered back-projection rather than iterative reconstruction. CoDe PET findings were compared with corresponding results of computed tomographic (CT) and magnetic resonance imaging (MRI), tissue biopsy, or clinical follow-up.

RESULTS

For staging, 52 sites were positive on CoDe PET or CT-MRI. CoDe PET detected 49 sites (94%), and CT-MRI showed 47 sites (90%). CoDe PET detected five more lymphomatous lesions and missed three lesions. For post-treatment evaluation, CoDe PET showed a positive predictive value of 100% and a negative predictive value of 83%, but the validated cases numbered only 11. For follow-up for recurrence, CoDe PET had a negative predictive value of 90%, but frequent false-positive findings were noted in the head and neck region as a result of underlying inflammatory changes.

CONCLUSIONS

For staging, FDG CoDe PET alone without attenuation correction is not sensitive enough to be used as an independent imaging method, especially for small abdominal lesions. However, it appears to be an accurate method for assessing residual disease and for patient follow-up.

Effect of the factor V Leiden mutation on the clinical expression of severe hemophilia A

To determine whether the factor V Leiden mutation is associated with decreased bleeding in individuals with severe hemophilia A, factor concentrate utilization, maximum annual number of bleeding episodes, and the prevalence of hemophilic arthropathy between carriers and non-carriers of the factor V Leiden mutation were compared. Heterozygosity for the factor V Leiden mutation was found in 6 of 137 subjects (4.4%). Carriers of the factor V Leiden mutation utilized less factor concentrate (geometric mean: 310 vs. 1185 units/kg/year) and had fewer bleeding episodes than non-carriers (proportion with 10 or fewer bleeding episodes in their worst year: 50 vs. 11%). However, the factor V Leiden mutation was not associated with the absence of arthropathy. The intron 22 inversion mutation of the factor VIII gene was tested for in a subgroup of 80 subjects, but it was not found to be a significant variable for any of the bleeding endpoints. The results of this small study are consistent with the hypothesis that the factor V Leiden mutation imparts a protective effect; however, a larger confirmatory study in which the factor VIII molecular defects can be controlled for is needed. Furthermore, most severe hemophiliacs who used fewer than 200 units/kg/year of factor concentrate or who had experienced 10 or fewer bleeding episodes per year did not carry the factor V Leiden mutation, suggesting that the proportion of severe hemophiliacs whose mild clinical course can be attributed to the factor V Leiden mutation is small.

The clinical usefulness of F-18 FDG coincidence PET without attenuation correction and without whole-body scanning mode in pulmonary lesions comparison with CT, MRI, and clinical findings

PURPOSE

This study was undertaken to assess the clinical usefulness of fluorine-18 flurodeoxyglucose (F-18 FDG) coincidence detection (CoDe) positron emission tomography (PET) of various lung lesions by comparing it with CT, MRI, and clinical findings.

MATERIALS AND METHODS

Forty-two patients with pulmonary lesions underwent CoDe PET using a dual-head gamma camera equipped with a 5/8 inch thick NaI (Tl) crystals. The patients were prepared for the study by overnight fasting. Data was acquired at approximately 1 hour after the intravenous injection of 111 to 370 MBq (3 to 10 mCi) of F-18 FDG. A spinal scan of the thorax was performed using a slip ring gantry for 30 minutes. After rebinning, routine tomographic slices were reconstructed without attenuation correction and the images were analyzed visually.

RESULTS

Pathologic diagnoses and staging were obtained at surgery in nine patients; in the remaining 33 patients, aspiration cytology was available. CoDe PET detected all 35 pathologically proved malignant lesions. In nine patients who underwent surgery, seven CoDe PET studies corresponded with pathologic staging, whereas in six of the nine patients, CT and MRI corresponded with the pathologic findings. Seven patients also had benign lesions that showed FDG uptake.

CONCLUSIONS

F-18 FDG CoDe PET was sensitive in the evaluation of lung lesions but was not specific for malignancy. F-18 FDG CoDe PET was more sensitive than CT and MRI in nodal staging in the limited number of patients studied thus far.

Multimerin processing by cells with and without pathways for regulated protein secretion

Multimerin is a massive, soluble, homomultimeric, factor V-binding protein found in platelet alpha-granules and in vascular endothelium. Unlike platelets, endothelial cells contain multimerin within granules that lack the secretory granule membrane protein P-selectin, and in culture, they constitutively secrete most of their synthesized multimerin. To further evaluate multimerin's posttranslational processing and storage, we expressed human endothelial cell prepromultimerin in a variety of cell lines, with and without pathways for regulated secretion. The recombinant multimerin produced by these different cells showed variations in its glycosylation, proteolytic processing, and multimer profile, and human embryonic kidney 293 cells recapitulated multimerin's normal processing for constitutive secretion by human endothelial cells. When multimerin was expressed in a neuroendocrine cell line capable of regulated protein secretion, it was efficiently targeted for regulated secretion. However, the multimerin stored in these cells was proteolyzed more extensively than normally occurs in platelets, suggesting that endoproteases similar to those expressed by megakaryocytes are required to produce platelet-type multimerin. The impact of the tissue-specific differences in multimerin's posttranslational processing on its functions is not yet known. Multimerin's sorting and targeting for regulated secretion may be important for its functions and its association with factor V in secretion granules.

A high rate of caesarean sections in an affluent section of Chennai: is it cause for concern?

BACKGROUND

While rising Caesarean section rates have been the subject of much attention and debate worldwide, there is not much information available on this rate and its potential adverse impact in India.

METHODS

Our survey was a standard Expanded Programme on Immunization 30-cluster design, carried out in an urban educated, middle/upper class population in Chennai. Mothers of 210 children aged 12-36 months were interviewed and data collected on immunization and breast-feeding practices. Since the mode of delivery was one of the questions, we could generate population-based data on the Caesarean section rate and its influence on breast-feeding.

RESULTS

Of the 210 babies, 95 (45%, 95% confidence interval: 39.1-51.3) had been delivered by Caesarean section. Two hundred and six of 210 babies (98%) had been breast-fed at some time. However, babies born by Caesarean section tended to be started late on breast-feeds were given prelacteal feeds more often, and colostrum less often when compared to babies delivered vaginally (all statistically significant).

CONCLUSIONS

Our study revealed a very high rate of Caesarean section in the selected metropolitan population. On purely scientific grounds, a rate of 40% to 50% is extremely difficult to justify. Though not conclusive, the data also suggest that Caesarean section may be adversely affecting some aspects of breast-feeding. There is a need for more data and audits on Caesarean section rates in India, and a wider debate on its potential adverse impact on the health of mothers and newborns.

Fluorine-18 fluorodeoxyglucose imaging using dual-head coincidence positron emission tomography without attenuation correction in patients with head and neck cancer

PURPOSE

An accurate, preoperative assessment of tumor extent and lymph node involvement is necessary to plan and tailor therapy for patients with head and neck cancer. Metabolic imaging with fluorine-18 fluorodeoxy-glucose (FDG) is a good method to detect primary tumors in the head and neck and to assess the involvement of lymph nodes, but it is not widely available because of the high cost of positron emission tomography (PET). Recently, an alternative method for using FDG was developed: coincidence detection PET (CoDe PET) using a gamma camera. The aim of this study was to evaluate the clinical utility of FDG CoDe PET using a gamma camera in patients with head and neck cancer.

MATERIALS AND METHODS

Thirty FDG CoDe PET studies without attenuation correction were performed in seven patients before therapy and in 19 patients after therapy (ages: 25-79 years, mean, 50 +/- 13 years; 18 men, 8 women) with various head and neck cancers. All patients had fasted for 6 to 12 hours and were injected with 111 to 370 MBq F-18 FDG 1 hour before imaging. Visually detectable focal FDG uptake in the primary tumor site or in the neck was considered positive except for physiologic uptake. The FDG CoDe PET studies were correlated with MRI. The gold standard for the presence of disease was the combination of repeated MRIs, endoscopic examination, and 3 months of follow-up clinical evaluation.

RESULTS

FDG CoDe PET had a detection rate that was comparable to that of MRI in the pretherapy group. However, in the posttherapy group, FDG CoDe PET could differentiate residual tumor or tumor recurrence from radiation change more accurately than could MRI. However, it had a less accurate detection rate for cervical node metastases because of asymmetric neck muscle uptake.

CONCLUSIONS

FDG CoDe PET is a sensitive and cost-effective method to detect primary tumor and lymph node involvement in primary head and neck cancers. It is also useful in differentiating residual tumor or tumor recurrence from posttherapy changes in patients with head and neck tumors.

Familial Evans syndrome: a report of an affected sibship

PURPOSE

This report describes the clinical course of three siblings, all of whom had Evans syndrome in childhood.

PATIENTS

The coexistence of autoimmune hemolytic anemia and thrombocytopenia, in the absence of a known underlying cause, led to the diagnosis of Evans syndrome in a 4-month-old girl and subsequently in her two brothers when they were 4 and 13 years old.

RESULTS

The 4-month-old girl had a life-threatening relapsing course unresponsive to corticosteroids, intravenous gamma-globulin, thymectomy, and cyclophosphamide. She eventually responded to splenectomy. Her two brothers had milder disease that responded to corticosteroids. Cytogenetic analyses revealed the presence of a familial Y;15 translocation in all three children and their father.

CONCLUSION

There are few reported cases of familial Evans syndrome, and they are usually associated with an inherited congenital abnormality. We report the unusual finding of three siblings with the disease and no known congenital abnormality.

Seroepidemiology of Helicobacter pylori infection in an urban, upper class population in Chennai

BACKGROUND

In India, no true population-based seroepidemiological data on Helicobacter pylori infection are available. Serological studies have been done on hospital-based subjects chosen predominantly from lower socioeconomic strata.

METHODS

A population-based serological study was done in a randomly selected urban, upper class population (children under 12 excluded). Of 163 households, 126 participated (response rate 77%); the number of respondents was 406. Blood was collected from 354 persons (response rate 87%). A latex agglutination test was used for serology. Demographic data, socioeconomic indicators and history of treatment for acid-peptic disease (APD) were also collected.

RESULTS

The overall seroprevalence was 49.4% (95% confidence interval 44.1-54.8). Seroprevalence increased with age, ranging from 21.1% in the 12-20 years age group to 76.2% in the > 70 years group (p = 0.0003), and with larger family size (p < 0.05); it was lower among those living in nuclear families (p < 0.03). No association was found with gender, treatment for APD, and number of generations living together.

CONCLUSIONS

Though the overall seroprevalence of H. pylori in this urban, educated, upper class population is high, the age-specific prevalence is different from what has been reported earlier in India; the pattern resembles that of a developed country.

Survival after cardiopulmonary resuscitation in an urban Indian hospital

BACKGROUND

Survival after cardiopulmonary resuscitation depends upon the quality of pre-hospital support, availability of resuscitation equipment and the competence of the resuscitator. There are few data on the prognosis of patients undergoing such resuscitation in India.

METHODS

In a retrospective analysis of 215 resuscitations done in a 125-bed community hospital between January 1995 and November 1997, return of spontaneous circulation and survival to discharge were evaluated. Multivariate methods were used to identify the predictors of successful outcome.

RESULTS

Of all the patients, 14.4% were alive at discharge. Survival after a cardiorespiratory arrest in the hospital was 18.4%, which was significantly better than survival after pre-hospital events (5.9%; p = 0.027). Multivariate predictors of survival at discharge were resuscitation duration of less than 20 minutes [odds ratio (95% confidence limit): 32.6 (6.5-164.3)], presentation with ventricular tachycardia or fibrillation [odds ratio: 18.5 (4.4-77.9)], in-hospital cardiorespiratory arrest [odds ratio: 5.2 (1.2-21.6)] and female sex [odds ratio: 3.2 (1.1-9.6)]. Bystander resuscitation, though rarely provided, increased survival at discharge (p = 0.026).

CONCLUSIONS

With 5.5 resuscitation attempts needed for one live discharge after in-hospital cardiorespiratory arrest and 17 attempts to save a life after pre-hospital events, our outcomes are comparable to those reported from developed nations. A return of pulse after shorter durations of cardiopulmonary resuscitation, ventricular fibrillation or tachycardia as the abnormal presenting rhythm, in-hospital location of cardiorespiratory (CR) arrest and female sex were independent predictors of live discharge. Age and aetiology of CR arrest did not influence the outcome.

Sanitation for rural communities: first win the people's support

A latrine project in an Indian village which failed because the inhabitants were scarcely brought into its planning and execution is contrasted with a moderately successful scheme in another village where a concerted effort was made to educate the community about the value of latrines and to obtain the people's participation.