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Epidemiology of cancer in Sarawak, East Malaysia.

A descriptive epidemiology of cancer in Sarawak, based on histopathology records in the Central Medical Laboratory, Kuching, Sarawsk, in 1981 and 1982 was presented. There were 8,219 patients from whom biopsies were taken and 485 from whom marrow biopsies were taken. Out of these, 1,326 were reported malignant. Most of the cases were from Kuching. There were slightly more males than females. The Chinese formed the majority of cases followed by the Sea Dayaks and Malays. The most common cancer sites among males were lymph nodes, nasopharynx, skin and stomach, while in the females the most common sites were the breast, cervix and lymph nodes. Among the Chinese the most common cancers were those of the nasopharynx in males, and breast in females. Among the Sea Dayaks, the most common cancers were those of the lymph nodes in males and cervix in females. Among the Malays, skin cancers were relatively common, and among the Land Dayaks nasopharyngeal cancers were common. Most of the patients were in the older age groups. The pattern of cancers has not changed much since 1966 and the findings of the present study are very similar to the series from the Institute of Medical Research, Kuala Lumpur, in 1969 to 1971.

Adolescent↗

Portfolio as a method for continuous assessment in an undergraduate health education programme.

A portfolio assessment system has been introduced into a biomedical science programme to promote both continuous learning and deep approaches to learning. Attention has been focused on creating harmony between the assessment system and the PBL curriculum of the programme. Biomedicine and laboratory work are central in the curriculum. The portfolio included evidence of laboratory work, personal reflections and certificates from the PBL tutor. The portfolio was assessed on three occasions over 20 weeks. The grades were 'pass' or 'fail'. The tutor certificate appeared to be a crucial part of the portfolio since a 'fail' in this part usually led to an overall 'fail'. Both students and teachers were concerned about ensuring that enough factual knowledge, as measured by a traditional test, had been achieved. The agreement was good enough for the pass or fail level but some expected differences were found at the detailed level. The course, including the portfolio, was evaluated orally during weekly whole-group meetings and using a questionnaire at the end. The students felt comfortable with the portfolio system and preferred it to a traditional test. The teachers felt that they needed to develop their teacher-student discussion skills and to improve their feedback on the reflections. Peer assessment between students is proposed as a line of action to enhance the credibility of the crucial tutor certificate. The portfolio might be an efficient tool for the students to concentrate their efforts on the most central concepts of medical laboratory work. The model will be developed through further discussions and better consensus among faculty.

Adult↗

[A census of medical genetics services in Argentina].

OBJECTIVE: To describe the medical genetics services in Argentina, in order to help organize a network to coordinate those services, decrease inequity in access to them, and promote the comprehensive development of medical genetics in the country. METHODS: In April-August 2004 a survey was conducted of centers providing medical genetics services in Argentina, looking at their human resources, diagnostic procedures, the services that patients use, and funding. The survey covered service centers that conduct genetic assessment, cytogenetic diagnostic testing, molecular biology testing, and biochemical testing to detect birth defects or genetic disorders. Centers that were devoted exclusively to research were not surveyed. RESULTS: A total of 134 centers fulfilled the selection criteria for the survey; 84 of them were private services, and the other 50 were publicly managed services, at universities and hospitals. The 50 public facilities had a total of 67 physicians who had studied clinical genetics, plus 133 non-medical laboratory professionals. A majority of the 50 centers performed clinical and cytogenetic diagnoses, with a smaller number performing molecular, biochemical, and prenatal diagnoses. More than 70% of the centers and human resources were located in an area that includes the city of Buenos Aires, the province of Buenos Aires, and the nearby north-central provinces of Córdoba and Santa Fe. The 50 public centers were found mainly in large cities; 10 of the country's 23 provinces had no public services. CONCLUSIONS: There is a great geographic disparity in the availability of resources as well as wide variability in the diagnostic procedures that are provided in the different service centers. The unequal distribution of the facilities is an organizational problem that will require the application of policies to guarantee minimum services for people in all regions of the country, as well as access to more complex diagnostic procedures.

Adult↗

A comparison of alternative arrangements for an out-of-hours chemical pathology service.

Until 1979, the out-of-hours chemical pathology service was the conventional on-call service in which the medical laboratory scientific officers (MLSOs) carried out analyses at the direct request of clinical staff. In 1980, during an industrial dispute, junior ward doctors were trained to use three simple instruments which are maintained by the chemical pathology department. In January, 1981, when the dispute was settled, the doctors continued to use these instruments. Analyses they could not make were done by the MLSO on call, but only after the requests were monitored by a chemical pathologist or biochemist. The result was an 80% reduction in the number of calls. When the monitoring was withdrawn in 1983, there was some increase in the number of MLSO calls, but this was still 35% less than that with the conventional system despite a 4-fold increase in the total number of analyses done out of hours between 1979 and 1984. Surveys in 1984 and in early 1985 revealed that most doctors preferred using the instruments to asking an MLSO to make the analysis.

Hospital Departments↗

Comparison of activity level and service intensity of male and female physicians in five fields of medicine in Ontario.

OBJECTIVE: To examine the extent to which physician's sex explains variation in the activity level and service intensity of a cohort of physicians in each of five medical fields after other sources of variation are taken into account. DESIGN: Data from the Ontario Ministry of Health (MOH) and the CMA were analysed by means of multivariate regression techniques for panel data. SETTING: Ontario. PARTICIPANTS: A total of 137 dermatologists, 974 general internists, 330 pediatricians and 941 psychiatrists and a random sample of 2771 family physicians and general practitioners who met the eligibility criteria. Physicians were eligible if they billed the MOH for at least three quarters in 1983, did not bill as a medical laboratory director, provided direct patient care, did not have an alternative funding arrangement with the MOH, remained in the same specialty throughout the study period (1983-90) and billed from an Ontario address. OUTCOME MEASURES: Three measures of total activity level (annual number of services provided, annual fee-for-service billings and annual mean number of patients seen per quarter) and one measure of service intensity (annual mean number of services per patient per quarter). RESULTS: Although several variables (e.g., full-time work status, age, type of practice and recent practice move) influenced the four measures examined, physician's sex contributed significantly to explaining variation in activity in 70% of the regression equations. The women provided 33.0% fewere services per year than the men in family and general practice (p < 0.001), 25.0% fewer services in general internal medicine (p < 0.01), 22.1% fewer services in pediatrics (p < 0.05) and 22.3% fewer services in psychiatry (p < 0.001). Total billings by the women in these fields were also significantly less than those of their male colleagues, the difference being greatest among the family physicians and general practitioners (28.0%) and the general internists (27.0%) (p < 0.001). The women in these four fields saw significantly fewer patients per quarter than their male colleagues, the difference being greatest in psychiatry (33.0%) (p < 0.001). Sex affected service intensity in three fields. The female psychiatrists (14.8%) (p < 0.001) and general intenists (5.5%) (p < 0.10) provided more services per quarter than their male colleagues, whereas the female family physicians and general practitioners delivered 2.2% fewer services per patient per quarter than their male colleagues (p < 0.01). In two specialties differences between women aged 40 years or less and those over 40 years were observed. In general internal medicine the younger women had higher activity levels than the older women (p < 0.01). Conversely, in dermatology the younger women had lower activity levels (p < 0.05) and provided fewer services per patient per quarter (p < 0.001) than the older women. CONCLUSIONS: Although physician's sex explained much of the variation in activity level and service intensity, even after other important correlates were controlled for, the type and extent of differences observed between female and male physicians depended on the particular medical field examined. To understand the effect of the large increase in the number of women on the physician workforce, more detailed analyses by medical field are needed of the volume, mix and intensity of services provided by men and women, with adjustment for any possible differences in the patients seen in their practices.

Age Factors↗

Audit on nuchal translucency thickness measurements in Flanders, Belgium: a plea for methodological standardization.

OBJECTIVES: To audit nuchal translucency thickness (NT) measurements for fetal aneuploidy screening in Flanders, and to estimate the impact of small variations in NT measurement on the screening result of two first-trimester screening algorithms: maternal age + NT (Algorithm A), and maternal age + NT + pregnancy associated plasma protein-A + free beta-human chorionic gonadotropin (Algorithm B). METHODS: We used the database of first-trimester combined screening, as collected by the General Medical Laboratory AML in Antwerp, Belgium, between 1 January 2001 and 1 April 2004. Audit was performed by establishing a delta-NT distribution curve for one trainee of The Fetal Medicine Foundation (FMF) and for a group of 263 other sonographers, in comparison with the FMF reference values. Risks for fetal aneuploidy were calculated at a cut-off value of 1 : 300 for Algorithm A and 1 : 150 for Algorithm B. These risks were recalculated in both algorithms after a modeled increase of all NT values by 0.1 or 0.2 mm. RESULTS: In a total of 592 measurements performed by the FMF trainee, the 5th, 50th and 95th percentiles of delta-NT measurements were at -0.41, +0.03 and +0.68 mm, respectively. These values were close to the FMF reference values. The screen-positive rate for this set of data was 4.4% (26/592) in both algorithms. For the 12 555 measurements of the 263 other sonographers, the 5th, 50th and 95th percentiles of delta-NT were at -0.81, -0.14 and +0.73 mm, respectively, which clearly indicates underestimation of NT in the lower range. In this set of data the screen-positive rate was 3.5% for both algorithms (439/12 555 for Algorithm A and 436/12 555 for Algorithm B). Also in this group, 5% (59/1186) of negative screening results at maternal age > or = 35 years in Algorithm A became positive after a modeled 0.1-mm increase in NT, whereas this was only in 1.2% (134/11 369) of tests at maternal age < 35 years (P < 0.0001). The overall increase of screen-positive rate in Algorithm A after an NT modification of +0.1 mm was 1.2% (152/12 555), significantly more than in Algorithm B (86/12 555; 0.7%) (P < 0.0001). CONCLUSION: In Flanders, there is a systematic underestimation of NT in comparison with the FMF reference range. Attempts to change these measurements according to the FMF criteria are crucial. This will mainly influence the screening results of women at advanced maternal age and of NT-based algorithms without the use of other parameters.

Adult↗

Financial incentives to perform medical procedures and laboratory tests: illustrative models of office practice.

Financial return is one of several factors that may affect a physician's decision to order services for a patient. The extent of financial incentives to perform in-office medical procedures and laboratory tests is illustrated by four hypothetical models of general internal medicine office practice. The model practices consist of fixed ratios of history and physical examinations to return visits, with numbers and types of medical procedures and laboratory tests increasing stepwise through the four models. The procedures and tests included are an electrocardiogram, urinalysis, complete blood count, sigmoidoscopy, tuberculin skin test, two-view chest x-ray, cardiovascular treadmill stress test, and an automated 12-channel blood chemistry test. Charges and office expenses are estimated at 1977 Northern California levels. Net incomes derived for the four models are as follows: $31,000, $55,000; $60,000; and $90,000. The demonstrated financial incentives, which apply not only to internal medicine, but to all fields of medical care, are in conflict with policies that would emphasize personal rather than technical services. National health insurance proposals should include a continuing review of medical services valuation.

California↗

Evaluating the quality of cancer care: development of cancer quality indicators for a global quality assessment tool.

BACKGROUND: The rise of managed care has increased interest in measuring, reporting, and improving quality of care. To date, quality assessment has relied on a leading indicator approach, which may miss important variations in care. The authors developed cancer specific indicators using a novel case-based approach for a quality measurement tool designed to compare different managed care organizations. METHODS: Based on a review of the literature, quality indicators were developed for 6 types of cancer and the human immunodeficiency virus (HIV) as well as 39 general adult conditions (GAC). The validity and feasibility of these candidate indicators were evaluated using three modified Delphi expert panels. The strength of evidence, type of care (preventive, acute, or chronic), function (screening, diagnosis, treatment, and follow-up), and modality (history, physical examination, laboratory, medication, or other intervention) of the cancer/HIV quality indicators were compared with indicators developed for GAC. RESULTS: The final system included 117 of the 145 proposed cancer/HIV quality indicators (81%) and 569 of the 705 proposed GAC indicators (81%). A greater percentage of the cancer/HIV indicators were based on evidence from clinical trials compared with the GAC indicators (59% vs. 31%; P = 0.001). Cancer/HIV had significantly more indicators pertaining to chronic care than did GAC (74% vs. 56%; P = 0.001) as well as more indicators for treatment (53% vs. 39%; P = 0.004). CONCLUSIONS: Using the case-based approach, it is feasible to develop quality indicators for cancer that cover the continuum of care. Future studies will evaluate the reliability and validity of measurements made using these indicators in three managed care plans.

Adult↗

Molecular genetic testing for adult-onset disorders: the evolving laboratory, physician, patient interface.

Molecular genetics is providing the power to predict and diagnose a variety of diseases. This is an evolving field, with new information being gained at a very rapid rate. Ultimately the molecular tools should be available to prevent and/or cure a number of diseases with genetic etiology. The molecular genetics laboratory is playing a pivotal role in effecting the utilization of this technology. However, molecular genetic testing is in many ways unlike other clinical laboratory testing. The process of molecular genetic testing and counseling is complex. The laboratory offering molecular genetic testing must be able to assess pedigrees, decide the proper test to perform and provide interpretation of the tests results obtained. Although standards governing the use of high-complexity genetic tests are evolving it is clear that the laboratory offering these tests will have to have on staff personnel trained specifically in molecular genetics. The challenge will be to stay abreast of evolving technology as well as standards and recommendations governing the use of these tests. We will review the process of molecular genetic testing and the issues that must be considered by laboratories who offer these tests.

Accreditation↗

Russia's imperial blood: was Rasputin not the healer of legend?

The only son of Russia's last Tsar, a great-grandson of Queen Victoria, continues to be used as the favorite example of the X-linked inheritance of hemophilia, in spite of the fact that this popular historical diathesis has never been confirmed by any form of modern medical laboratory testing. Certain to be controversial, a new study of the symptoms that were witnessed by those who were closest to the teenaged Russian heir now raises the possibility that his blood disorder might well have been something other than hemophilia. The key to discovering Tsarevich Alexei's true diagnosis is found in those now legendary allegations that the infamous "Mad Monk", Grigory Rasputin, had possessed a power of healing that was somehow responsible for the young boy's mysterious history of spontaneous recoveries. If we are to accept the popular diagnosis of history and call it a clotting factor deficiency, then the boy's now famous sudden recoveries will remain a complete mystery. The so-called "Mad Monk" Rasputin, as a direct result of the revolutionary propaganda of the time, is then overblown into a larger-than-life legend. If, however, we are to change the diagnosis and call it a platelet disorder, then the air is let out of the legend, and Rasputin is revealed to have been nothing more than a very ordinary middle-aged Siberian hippie who did not possess any healing powers at all.

Anemia, Hemolytic↗

New developments in clinical laboratory molecular assays.

The new technological advances influencing the clinical laboratory are discussed with immediate and future areas of new clinical laboratory tests. The new technological advances include 1) monoclonal and designer antibodies, 2) solid phase and homogeneous automated immunochemical assays, 3) DNA/RNA nucleotide tests, 4) synthetic peptides, and 5) biosensors. The major factors which influence the need for future laboratory tests are 1) technology, 2) advances in therapeutic agents, 3) governmental regulations, and 4) health care economics.

Antibodies↗

Modified salting-out method: high-yield, high-quality genomic DNA extraction from whole blood using laundry detergent.

Different approaches have been used to extract DNA from whole blood. In most of these methods enzymes (such as proteinase K and RNAse A) or toxic organic solvents (such as phenol or guanidine isothiocyanate) are used. Since these enzymes are expensive, and most of the materials that are used routinely are toxic, it is desirable to apply an efficient DNA extraction procedure that does not require the use of such materials. In this study, genomic DNA was extracted by the salting-out method, but instead of using an analytical-grade enzyme and chemical detergents, as normally used for DNA isolation, a common laundry powder was used. Different concentrations of the powder were tested, and proteins were precipitated by NaCl-saturated distilled water. Finally, DNA precipitation was performed with the use of 96% ethanol. From the results, we conclude that the optimum concentration of laundry powder for the highest yield and purity of isolated DNA is 30 mg/mL. The procedure was optimized, and a final protocol is suggested. Following the same protocol, DNA was extracted from 100 blood samples, and their amounts were found to be >50 microg/mL of whole blood. The integrity of the DNA fragments was confirmed by agarose gel electrophoresis. Furthermore, the extracted DNA was used as a template for PCR reaction. The results obtained from PCR showed that the final solutions of extracted DNA did not contain any inhibitory material for the enzyme used in the PCR reaction, and indicated that the isolated DNA was of good quality. These results show that this method is simple, fast, safe, and cost-effective, and can be used in medical laboratories and research centers.

DNA↗

High incidence of Coxiella burnetii markers in a rural population in France.

Since Coxiella burnetii, the causative agent of Q fever, is often transmitted from goats and sheep to humans through aerosols, we examined the sera from 168 persons involved in goat breeding in the Centre region of France and 40 members of veterinary and medical staff from the same region for the presence of antibodies against C. burnetii. An immunofluorescence assay was used to detect the presence of antibodies of the IgG isotope against epitopes from phase II of C. burnetii, which are the first antibodies to appear in infected people, and from phase I, which reflect more chronic stages of the infection. Our serological survey showed that most of the tested sera were positive for C. burnetii markers, indicating at least an encounter with the bacterium. In the overall population of 208 subjects, 71% of the sera had antibodies against phase II epitopes (titres > or = 1:40). Among the goat farmers and their immediate families, 78% had antibodies against phase II and 33% against phase I (titres > or = 1:40). Considering only high titres (> or = 1:320), though, only 37% of the farmers had antibodies against phase II and 15% against phase I. Only 3 out of 12 veterinarians working in the field had high titres of antibodies against phase II and phase I, while none of 28 members of veterinary and medical laboratories had significant levels of antibodies. These results emphasize the need for closer surveillance of populations at risk for Q fever, to prevent the infection by C. burnetii from reaching chronic stages of the disease.

Agricultural Workers' Diseases↗

Central nervous system tuberculosis: MRI.

The MRI findings of 18 proven cases of central nervous system (CNS) tuberculosis were reviewed; 10 patients were seropositive for HIV. All had medical, laboratory, or surgical proof of CNS tuberculosis. Eleven patients had meningitis, of whom two also had arachnoiditis. Five patients had focal intra-axial tuberculomas: four brain masses and one an intramedullary spinal lesion. Two patients had focal extra-axial tuberculomas: one in the pontine cistern, and one in the spine. In all 11 patients with meningitis MRI showed diffuse, thick, meningeal enhancement. All intraparenchymal tuberculomas showed low signal intensity on T2-weighted images and ring or nodular enhancement. The extra-axial tuberculomas had areas isointense or hypointense relative to normal brain and spinal cord on T2-weighted images. Although tuberculous meningitis cannot be differentiated from other meningitides on the basis of MR findings, intraparenchymal tuberculomas show characteristic T2 shortening, not found in most other space-occupying lesions. In the appropriate clinical setting, tuberculoma should be considered.

Adult↗

High-dose interferon-alpha2b treatment prevents chronicity in acute hepatitis C: a pilot study.

Acute hepatitis C takes a chronic course in 50-80% of cases. Results with interferon treatment are conflicting. To evaluate the efficacy of high-dose interferon treatment, we initiated a pilot study in 1992 using 10 MU interferon-alpha2b administered subcutaneously daily until normalization of serum transaminase concentrations. Treatment was begun when a diagnosis of acute hepatitis C was established. HCV-RNA was tested using PCR prior to treatment, three times weekly during the first two weeks of treatment, and then once weekly until the end of therapy. During the 15-month follow-up, HCV-RNA tests were performed monthly up to month 6 and every two to three months thereafter. Twenty-four patients were enrolled at the time of writing; age ranged from 18 to 76 years (mean = 32), and nine patients were men. All patients presented with cholestatic hepatitis; 19 were actively abusing intravenous drugs, four had no known parenteral exposure, and one was a medical laboratory technician. All patients were anti-HCV positive, HCV-RNA positive, and HIV negative. Five patients were infected with genotype 3, five with genotype 1a, five with genotype 1b, three with genotypes 3 and 2, and one with genotypes 1 and 2. All patients exhibited normalized serum transaminase concentrations within 18-43 days; HCV-RNA became negative in all patients within 4-12 days. Toxicity did not exceed grade 1 and disappeared within three days of treatment. In the follow-up period, which ranged from six to 29 months (mean = 19.5 +/- 10.4), serum ALT concentrations remained normal and HCV-RNA remained negative in all patients except two dropouts and two patients who developed relapsing disease after having been HCV-RNA negative for three and eight months, respectively. In both patients, the same HCV genotype 3 reemerged. Serum ALT concentrations ranged from 531 to 1940 IU/liter (mean = 1055; normal < 22). Concentrations of HCV-RNA (Quantiplex; Chiron, Emeryville, California) were < 3.5 x 10(5) eq/ml in nine of 14 PCR-positive patients. In the other five patients, concentrations ranged from 10.4 x 10(5) eq/ml to 131.6 x 10(5) eq/ml (mean = 69.6 x 10(5)). No correlation was observed between HCV-RNA concentrations and serum ALT concentrations at presentation (r = 0.331; P = 0.67) and total dose of interferon-alpha2b administered until normalization of ALT (r = -0.088; P = 0.74). Twenty-two of 24 patients completed treatment (two were noncompliant). Of these, 20 achieved a complete response (HCV-RNA negative for at least six months). Two of these patients relapsed, and 18 (90%) remained HCV-RNA negative for 18.65 (+/-9.7) months. These findings suggest that high-dose interferon-alpha2b is well tolerated and effective in preventing a chronic course of hepatitis C infection.

Acute Disease↗