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Biomedical subjects

D A Enarson

Publications and source records attributed to D A Enarson.

At least 145 records · Page 8Linked to original sources
PubMed1985

Predictors of bronchial hyperexcitability in grainhandlers.

We have studied bronchial hyperexcitability to methacholine (defined as a fall of at least 20 percent in FEV1 at 8 mg/ml or lower) in 504 white male grainhandlers working in terminal elevators in the Port of Vancouver. There was a significant association between bronchial hyperexcitability and level of FEV1; for a 10 percent decrease in percent of predicted FEV1, bronchial hyperexcitability was twice as common. Among those with bronchial hyperexcitability, the PC20 was significantly related to the FEV1. Grainhandlers with immediate skin reactivity to common allergens were twice as likely to have bronchial hyperexcitability. There was a significant increase in the prevalence of bronchial hyperexcitability with increasing duration of employment. Grainhandlers with chest tightness and breathlessness were over twice as likely to have bronchial hyperexcitability. We did not observe an increased prevalence of bronchial hyperexcitability in smokers, and there was no difference between age groups. We conclude that the determinants of bronchial hyperexcitability in this population include baseline FEV1, immediate skin reactivity to common allergens, some respiratory symptoms, and cumulative exposure to grain dust.

Adult↗
PubMed1984

Active tuberculosis in Indochinese refugees in British Columbia.

The incidence of active tuberculosis in 8692 Indochinese refugees admitted to British Columbia between 1979 and 1981 was reviewed. In the first 3 months after entry into the province the rate was extremely high--estimated at 1890/100 000 (126 times the provincial average). A large proportion of these cases were of primary or minimal pulmonary tuberculosis. However, although the proportion of cases of minimal pulmonary tuberculosis was twice the provincial average, the proportion of these cases that were confirmed by culture was only one third the provincial average; this suggests some overdiagnosis in this period. In the subsequent 21 months of residence the incidence of active tuberculosis was also high, at 353/100 000, which was more than 20 times the provincial average. The distribution of cases by severity was closer to the provincial distribution in this period, but advanced disease accounted for a far smaller proportion of cases in both periods than it did in 1980 in the entire province.

Adolescent↗
PubMed1984

Ten year evaluation of a trial of chemoprophylaxis against tuberculosis in Frobisher Bay, Canada.

A trial of chemoprophylaxis to prevent tuberculosis in Canadian Inuit (Eskimos) was carried out in Frobisher Bay, Canada during 1971-1974. A completely supervised regimen of isoniazid and ethambutol thrice weekly for 18 months was administered. A 10-year evaluation of 370 treated persons and 217 control subjects demonstrates the sustained value of adequate chemoprophylaxis in reducing the risk of developing active tuberculosis in the 3 groups under study--1, those with a previous episode of active tuberculosis, 2, positive tuberculin reactors with normal chest X-ray and 3, BCG vaccinated individuals with large tuberculin reactions. There were 3 cases of active disease in the treated group, a risk of 0.1% per annum, and 13 cases among the controls, a risk of 1.0% per annum.

Adolescent↗
PubMed1984

Occupational exposure to chlorophenates: toxicology and respiratory effects.

We have identified 71 chlorophenate-exposed sawmill workers as part of a group undergoing an extensive health and environmental evaluation in a pulp mill. We have compared this group with a group (351) with no physical proximity to the area in which chlorophenates were used. We demonstrated a gradient of exposure from 230 ppb in urine and 919 ppb in serum for those directly handling the contaminated wood, to 139 ppb in urine and 354 ppb in serum for those working in the area but not in manual contact as compared with serum levels of 84 ppb in the unexposed group. We noted that the bulk chemical was primarily in the tetrachloro-form but the serum levels contained more pentachlorophenate. The urine proportions were intermediate, approximating the bulk chemical proportions at the lower levels of exposure. We did not find an excess prevalence of respiratory symptoms or spirometric abnormalities which could be explained by the chlorophenate exposure.

Adult↗
PubMed1984

Routine urinalysis in a male working population: effects of some personal and lifestyle factors.

The most frequently positive urinalysis findings in a population of white working men were leukocytes (78.7%), erythrocytes (37.3%) and protein (25.4%). There was a significant correlation among the variables: cells were associated with protein, protein was associated with casts, erythrocytes were associated with granular casts and oxalate crystals. Protein and granular casts were significantly associated with serum creatinine. The prevalence of blood cells varied with age, showing a bimodal distribution. Oxalate crystals were significantly more common in subjects with a history of urinary tract infection; triple phosphate crystals were associated with a history of urinary calculi. Protein and erythrocytes were significantly more frequent in smokers. Leukocytes were significantly more frequent in drinkers. We conclude that there are important factors that must be taken into account in the interpretation of urinalysis findings.

Adult↗
PubMed1984

Microfilaremia and peak expiratory flow rate, Philippines.

We studied the peak expiratory flow rate in residents of two villages in the Philippines; one with a high prevalence, one with an intermediate prevalence of microfilaremia. We also determined the presence and level of microfilaremia in the individuals by examining thick films of 40 cmm of peripheral blood taken at night. We have found that the slope of the peak expiratory flow with age is steeper in the village with a high prevalence of microfilaremia and that it is also steeper in individuals from the high prevalence village with microfilaremia as compared with those without parasitemia. We conclude that there is a relationship between the presence of microfilariae and airflow obstruction.

Adolescent↗
PubMed1982

Tuberculous pleurisy.

A review of the records for all cases of tuberculous pleurisy notified in Canada from 1970 through 1974 and in British Columbia from 1967 through 1976 showed that in the periods studied the annual incidence of this condition was low, just under nine cases per million population, and was declining. The disease commonly occurred a few months after a primary infection with tubercle bacilli. Bacteriologic confirmation of the diagnosis was possible in only 40% of the cases since biopsy specimens were not consistently cultured.

Adolescent↗
PubMed1982

Filariasis in an upland population in the Philippines.

An epidemiological survey of filariasis was undertaken among the Mangyan villages of Mindoro, Philippines. The prevalence of microfilaremia was 10.2%. There were two foci of the disease; one in the northeast and the other in the southeast. The prevalence of lymphedema was very low. The prevalence of chronic productive cough was high and was associated with the presence of microfilaria.

Adolescent↗
PubMed1980

Non-respiratory tuberculosis in Canada. Epidemiologic and bacteriologic features.

Of the total cases of tuberculosis reported in Canada between 1970-1974, approximately one-sixth (3671 cases) involved primarily non-respiratory organs. Common diagnostic entities were genitourinary tuberculosis (1516 cases), lymphadenitis (1083 cases), bone and joint tuberculosis (555 cases), gastrointestinal tuberculosis (155 cases) and meningitis (138 cases). The remainder (224 cases) involved a wide variety of organs. Between 1967 and 1977 the morbidity rates of most non-respiratory manifestations steadily declined, the decline in meningitis being particularly marked. In contrast, lymphadenitis did not decline to the same extent, reflecting changing immigration patterns. The major diagnostic entities differed in their age and sex patterns and in their contribution to total cases by birthplace and ethnic group. In particular, the preponderance of lymphadenitis in females, and in the Asian-born was striking. Mycobacterium bovis was isolated infrequently and bacillary resistance to antituberculosis drugs was also uncommon. In a substantial proportion of cases, active tuberculosis was present concurrently at another site, or there was historical or radiologic evidence of previous active tuberculosis. Despite this additional evidence, delay and failure of diagnosis were common. An increased clinical awareness of tuberculosis is required, particularly in view of the often enigmatic presentation of non-respiratory disease.

Age Factors↗
PubMed1980

Incidence of tuberculosis among Scandinavian immigrants in Canada.

Tuberculosis incidence in Finland is at least five times higher than in the other Scandinavian countries. A study of the incidence of tuberculosis in immigrants to Canada from Finland and the other Scandinavian countries shows a remarkable similarity between the rates of the immigrants and those who remained in their country of origin, even after 40 years of residence in the new country. The early experience of tuberculosis thus predetermines future susceptibility throughout the life span of the group.

Adult↗
PubMed1979

Bone and joint tuberculosis: a continuing problem.

Although tuberculous disease of bones and joints is becoming uncommon, it still occurs and may cause devastating sequelae. It is frequently not diagnosed prior to the onset of permanent damage to the joints or spine; the most important reason for this delay may be the fact that it is not considered in the differential diagnosis of monoarthritis or back pain. Most persons with the disease have other evidence of tuberculosis. Not infrequently an aggressive approach (including synovial biopsy or surgical exploration of the back) is needed to confirm the diagnosis when there are no other clues.

Adolescent↗
PubMed1978

Failure of diagnosis as a factor in tuberculosis mortality.

In British Columbia between January 1970 and December 1974 active tuberculosis was diagnosed only after death in 69 cases; this was more frequent for miliary tuberculosis (31% of reported cases) than for advanced pulmonary tuberculosis (3% of cases). Although 28% of the patients were more than 75 years old, some were much younger, and 38% of the latter were alcoholics. More than 50% of the patients had been hospitalized before death, for a mean of 14.5 days; they were most frequently thought to have pneumonia or cancer at the time of death. Clearly, increased awareness of the continuing presence of tuberculosis in our society is needed.

Aged↗
PubMed1978

Central nervous system histoplasmosis with obstructive hydrocephalus.

A case of central nervous system histoplasmosis complicated by obstruction of the fourth ventricle is described. The patient rarely exhibited systemic symtoms of infection despite positive cultures for Histoplasma capsulatum from bone marrow, blood and urine. Infection recurred despite the administration of a total of 5 g of systemic amphotericin B. An additional course combined with intrathecal amphotericin B was terminated because of transverse myelitis.

Adolescent↗
PubMedDate not supplied

The yield of acid-fast bacilli from serial smears in routine microscopy laboratories in rural Tanzania.

Routine results of direct examination of sputum smears for acid-fast bacilli from 34 laboratories in Tanzania were analysed. These represented 8 regions providing 94 laboratory-years of work; 61,580 tuberculosis suspects were evaluated with the aid of 141,371 smears. The average proportion of cases found among suspects was 18.9% (range 14.3-23.8% in the 8 regions). The number of cases missed among suspects with incomplete examinations was calculated based on the number observed among suspects with a complete set of 3 smears examined, and an incremental yield of 83.4% with the first, 12.2% with the second, and 4.4% with the third smear was estimated for the total number of expected cases. These data suggest that (i) the method frequently employed for calculating requirements for laboratory supplies in low income countries, based on the estimate that 10 suspects need examination to identify one case of sputum smear-positive tuberculosis, is generous in the context of Tanzania and (ii) under routine conditions the incremental yield from a third smear examination after 2 negative examinations is relatively small.

Humans↗
PubMedDate not supplied

Two 8-month regimens of chemotherapy for treatment of newly diagnosed pulmonary tuberculosis: international multicentre randomised trial.

BACKGROUND: A WHO-recommended 8-month regimen based on ethambutol and isoniazid was evaluated in a randomised clinical trial against a 6-month standard regimen. METHODS: 1355 patients with newly diagnosed smear-positive pulmonary tuberculosis were randomly assigned one of three regimens: daily ethambutol, isoniazid, rifampicin, and pyrazinamide for 2 months, followed by ethambutol and isoniazid for 6 months (2EHRZ/6HE); the same drugs but given three times weekly in the initial intensive phase (2[EHRZ]3/6HE); or the same initial intensive phase as the first regimen, followed by 4 months of daily rifampicin and isoniazid (2EHRZ/4HR). Follow-up was to 30 months after the start of chemotherapy. Sputum was regularly examined by microscopy and culture. Unfavourable outcome was defined as failure during treatment or relapse afterwards. Analyses were by intention to treat. FINDINGS: At 2 months, a significantly higher proportion of patients assigned the daily intensive phase than of those assigned the three-times-weekly regimen were culture negative (700/828 [85%] vs 333/433 [77%], p=0.001). 12 months after the end of chemotherapy, the proportions of unfavourable outcomes were 36 of 346 (10%) with 2EHRZ/6HE, 48 of 351 (14%) with 2(EHRZ)3/6HE, and 17 of 347 (5%) with 2EHRZ/4HR. Both 8-month regimens were significantly inferior to the control 6-month standard regimen (difference between control and 2EHRZ/6HE 5.5% [95% CI 1.6 to 9.4]; between control and 2(EHRZ)3/6HE 8.8% [4.5 to 13.0]). Adverse effects leading to interruption of treatment for 7 days or longer occurred in 28 patients (12 2EHRZ/6HE, five 2[EHRZ]3/6HE, 11 2EHRZ/4HR). INTERPRETATION: The results of this study must be taken into account in recommendations on management of new cases of smear-positive tuberculosis.

Adolescent↗