Allergy to laboratory animals in laboratory technicians and animal keepers.

The prevalence of allergy to laboratory animals (LAA) was investigated in laboratory technicians and animal keepers. In a questionnaire 41 of 101 technicians reported symptoms provoked by work with laboratory animals. On clinical investigation 30 were found to have symptoms and signs related to contact with animals, and allergy was confirmed by radioallergosorbent tests (RAST) and skin tests in 19. All had rhinitis and 10 also had bronchial asthma. Forty seven other technicians who had stopped working with laboratory animals showed the same relative numbers of respiratory tract symptoms and of confirmed allergy to laboratory animals as did those currently handling animals. Seven of 23 animal keepers had work related symptoms. LAA symptoms were found in four and confirmed animal allergy in two. All four animal keepers with animal related symptoms had rhinitis, none had bronchial asthma. Positive animal RAST and skin tests were found only among people with animal related symptoms. A history of atopic disease was commoner among those with positive animal test results than among those with negative test results. No relation between smoking and the development of allergy to laboratory animals emerged. Simple prophylactic measures often sufficed to help technicians with animal related symptoms to remain at work.     

Allergy to laboratory animals in laboratory technicians and animal keepers

The prevalence of allergy to laboratory animals (LAA) was investigated in laboratory technicians and animal keepers. In a questionnaire 41 of 101 technicians reported symptoms provoked by work with laboratory animals. On clinical investigation 30 were found to have symptoms and signs related to contact with animals, and allergy was confirmed by radioallergosorbent tests (RAST) and skin tests in 19. All had rhinitis and 10 also had bronchial asthma. Forty seven other technicians who had stopped working with laboratory animals showed the same relative numbers of respiratory tract symptoms and of confirmed allergy to laboratory animals as did those currently handling animals. Seven of 23 animal keepers had work related symptoms. LAA symptoms were found in four and confirmed animal allergy in two. All four animal keepers with animal related symptoms had rhinitis, none had bronchial asthma. Positive animal RAST and skin tests were found only among people with animal related symptoms. A history of atopic disease was commoner among those with positive animal test results than among those with negative test results. No relation between smoking and the development of allergy to laboratory animals emerged. Simple prophylactic measures often sufficed to help technicians with animal related symptoms to remain at work.     

Laboratory exposures to staphylococcal enterotoxin B

Staphylococcal enterotoxins are 23- to 29-kDa polypeptides in the bacterial superantigen protein family. Clinical symptoms from intoxication with staphylococcal enterotoxins vary by exposure route. Ingestion results in gastrointestinal symptoms, and inhalation results in fever as well as pulmonary and gastrointestinal symptoms. Review of occupational exposures at the U.S. Army Medical Research Institute of Infectious Diseases from 1989 to 2002 showed that three laboratory workers had symptoms after ocular exposure to staphylococcal enterotoxin B (SEB). Conjunctivitis with localized cutaneous swelling occurred in three persons within 1 to 6 hours after exposure to SEB; two of these persons also had gastrointestinal symptoms, which suggests that such symptoms occurred as a result of exposure by an indirect cutaneous or ocular route. Ocular exposures from SEB resulting in conjunctivitis and localized swelling have not previously been reported. Symptoms from these patients and review of clinical symptoms of 16 laboratory-acquired inhalational SEB intoxications may help healthcare workers evaluate and identify SEB exposures in laboratory personnel at risk.     

Laboratory animal allergy in a pharmaceutical company

A cross sectional survey was carried out on 138 workers exposed to laboratory animals. Sixty (44%) had symptoms in a self completed questionnaire that were consistent with laboratory animal allergy (LAA) of whom 15 (11%) had chest symptoms. There was a positive skin prick test to one or more animal urine extracts (rat, mouse, guinea pig, rabbit) in 13% and 38% had a positive radioallergosorbent test to urine extract. LAA chest symptoms were almost five times more common in atopic than non-atopic subjects (who were distinguished by skin test response to common, non-animal aeroallergens). A positive skin test to animal urine was associated with LAA chest symptoms and with atopy. Nose, eye, or skin symptoms without chest symptoms were not associated with atopy. There was an inverse relation between duration of employment at the firm and LAA chest symptoms, suggesting selection of affected people out of employment with animals.     

Laboratory animal allergy in a pharmaceutical company.

A cross sectional survey was carried out on 138 workers exposed to laboratory animals. Sixty (44%) had symptoms in a self completed questionnaire that were consistent with laboratory animal allergy (LAA) of whom 15 (11%) had chest symptoms. There was a positive skin prick test to one or more animal urine extracts (rat, mouse, guinea pig, rabbit) in 13% and 38% had a positive radioallergosorbent test to urine extract. LAA chest symptoms were almost five times more common in atopic than non-atopic subjects (who were distinguished by skin test response to common, non-animal aeroallergens). A positive skin test to animal urine was associated with LAA chest symptoms and with atopy. Nose, eye, or skin symptoms without chest symptoms were not associated with atopy. There was an inverse relation between duration of employment at the firm and LAA chest symptoms, suggesting selection of affected people out of employment with animals.     

Allergy to laboratory animals: an epidemiological study.

A large cross sectional survey was carried out using a self administered questionnaire to examine the prevalence of laboratory animal allergy (LAA) and the factors associated with its development. Out of 5641 workers who were exposed to animals at 137 laboratory animal facilities in Japan, 23.1% had one or more allergic symptoms related to laboratory animals. The commonest symptom as rhinitis. About 70% of LAA subjects developed symptoms during their first three years of exposure. Atopy (past and family history), the number of animal species handled, and the time spent in handling correlated significantly with the development of LAA as did some types of job. A close relation between nasal symptoms and exposure to rabbits and between skin symptoms and exposure to rats were found. LAA subjects developed symptoms most quickly to rabbits.     

Allergy to laboratory animals: an epidemiological study.

A large cross sectional survey was carried out using a self administered questionnaire to examine the prevalence of laboratory animal allergy (LAA) and the factors associated with its development. Out of 5641 workers who were exposed to animals at 137 laboratory animal facilities in Japan, 23.1% had one or more allergic symptoms related to laboratory animals. The commonest symptom as rhinitis. About 70% of LAA subjects developed symptoms during their first three years of exposure. Atopy (past and family history), the number of animal species handled, and the time spent in handling correlated significantly with the development of LAA as did some types of job. A close relation between nasal symptoms and exposure to rabbits and between skin symptoms and exposure to rats were found. LAA subjects developed symptoms most quickly to rabbits.     

Occupational asthma in a mineral analysis laboratory.

An epidemic of symptoms suggestive of occupational asthma in workers in a mineral analysis laboratory necessitating exposure to vapours of hydrochloric, hydrofluoric, nitric, perchloric, and sulphuric acid solutions was investigated. Variable airflow obstruction was confirmed by serial measurement of FEV1 in two subjects who showed 18% and 22% fall in FEV1 during a workshift. Of a workforce of 21 laboratory staff, 20 took part in a study of ventilatory capacity and bronchial reactivity. All but one subject had normal ventilatory capacity but five had bronchial hyperreactivity (PC20 less than or equal to 8 mg/ml histamine). Four of the five with hyperreactivity had a history of chest tightness at work whereas only two subjects with chest tightness had PC20 greater than 8 mg/ml (p less than 0.01). Other work related symptoms were cough (two subjects) and breathlessness (three subjects). Four of the subjects with bronchial hyperreactivity were atopic, suggesting that hyperreactivity may have predated exposure to irritant material at work and resulted in their being susceptible to the development of symptoms and raises the possibility of identifying susceptible subjects by preplacement examination. In two of these subjects, however, bronchial reactivity has returned to normal after 205 and 376 days away from work, suggesting that bronchial inflammation resulted from occupational exposure to acid vapours.     

Occupational asthma in a mineral analysis laboratory

An epidemic of symptoms suggestive of occupational asthma in workers in a mineral analysis laboratory necessitating exposure to vapours of hydrochloric, hydrofluoric, nitric, perchloric, and sulphuric acid solutions was investigated. Variable airflow obstruction was confirmed by serial measurement of FEV1 in two subjects who showed 18% and 22% fall in FEV1 during a workshift. Of a workforce of 21 laboratory staff, 20 took part in a study of ventilatory capacity and bronchial reactivity. All but one subject had normal ventilatory capacity but five had bronchial hyperreactivity (PC20 less than or equal to 8 mg/ml histamine). Four of the five with hyperreactivity had a history of chest tightness at work whereas only two subjects with chest tightness had PC20 greater than 8 mg/ml (p less than 0.01). Other work related symptoms were cough (two subjects) and breathlessness (three subjects). Four of the subjects with bronchial hyperreactivity were atopic, suggesting that hyperreactivity may have predated exposure to irritant material at work and resulted in their being susceptible to the development of symptoms and raises the possibility of identifying susceptible subjects by preplacement examination. In two of these subjects, however, bronchial reactivity has returned to normal after 205 and 376 days away from work, suggesting that bronchial inflammation resulted from occupational exposure to acid vapours.     

A prospective study of genital infections in a family-planning clinic. 1. Microbiological findings and their association with vaginal symptoms

A prospective study of genital infection was conducted in four inner-city family-planning clinics. Fifteen per cent of routine attenders had symptoms and signs of vaginal infection and many more women attended primarily because of symptoms. Among the women with both signs and symptoms, 70% had positive laboratory findings, Trichomonas vaginalis, Candida albicans and bacterial vaginosis being equally prevalent. Measurement of vaginal pH in the clinic was the single most useful clinical finding for directing empirical therapy. Among patients with a discharge confirmed on examination and an abnormally high pH, 72% had either T. vaginalis or bacterial vaginosis. Neisseria gonorrhoeae was isolated from 4% of women with, and 1% of those without, symptoms. We believe that it is worthwhile to investigate patients presenting to family-planning clinics with vaginal symptoms. No single specimen was found ideal for all pathogens, a cervical swab is better for gonococci and also for T. vaginalis but a vaginal swab is needed for candida and bacterial vaginosis.     

High levels of isocyanic acid in smoke generated during hot iron cauterization

Abstract

Pyrolysis of nitrogen containing biofuels generates isocyanic acid (ICA) and we here studied if ICA also is present in cauterization smoke. Air sampling was performed when animal technicians that had developed airway symptoms worked with dehorning. Tissue heated in a laboratory model was used to mimic cauterization. ICA in air at the workplace exceeded 10 times the national exposure limit. In the laboratory, the ICA generated per mg tissue from heated hair, horn and nail was 13.9?±?7.8, 24.0?±?4.1 and 32.0?±?2.9?µg, respectively. Three workers were medically examined and two were diagnosed with asthma and a third had severe airway problem that resembled asthma. The study shows that high levels of ICA are generated during cauterization of nitrogen-containing tissue. If this could trigger airway symptoms deserves to be investigated further.     

Clinical reasoning and decision-marking in practice. A general practitioner with long-standing anaemia

In order to calibrate his haemoglobin meter, a general practitioner had his own haemoglobin level checked regularly at a nearby laboratory. At 37 years of age, one of these assays revealed 7,0 mmol/l. Because he had no symptoms, he prescribed himself iron-substitution therapy but the haemoglobin concentration did not normalise. At 52 years of age, the patient increasingly suffered from fatigue and exertional dyspnoea and had intermittent abdominal pain, distension and rumbling. Biopsies of the small intestine revealed crypt hypertrophy and intraepithelial lymphocytosis: signs ofcoeliac disease. The symptoms disappeared when the patient started to use a gluten-free diet. The haemoglobin level also normalised. Coeliac disease must be considered in the differential diagnosis of iron-deficiency anaemia.     

An outbreak of Brucella melitensis infection by airborne transmission among laboratory workers.

An outbreak of acute brucellosis infection was detected among the employees of a biologicals manufacturing laboratory located in Girona, Spain. The first cases appeared six weeks after a vaccine with attenuated Brucella melitensis, Rev-1 had been produced for one week. A clinical and epidemiologic investigation conducted among the 164 employees found 22 patients with clinical symptoms and positive serology, and six patients detected by serology only (attack rate: 17.1 per cent). Blood cultures were obtained from two patients and Brucella melitensis was isolated. Employees working in areas with open windows above the laboratory air extracting system had an attack rate of 39.5 per cent, substantially higher than those working in other locations. When vaccine was manufactured again, an electric oven reaching 300 degrees C had been installed in the air extracting system just before its exit to the exterior. Appropriate culture medium plates were exposed to the laboratory air before and after passing through the oven. Brucellae were isolated from the plates exposed to the air before passing through the oven but not after doing so.     

Allergy to laboratory animals: a retrospective and a prospective study.

Twenty four volunteers who had been allergic to laboratory animals for some years were examined by means of a questionnaire paying particular attention to symptoms associated with rats and by serological and skin tests with extracts of rat urine (retrospective study). Nasal and eye symptoms were reported by 21 and 16 individuals respectively: 13 had asthma. Positive skin tests and high levels of specific IgE antibody to rat urine extract were found in 17 of the more severely affected individuals and this group included 12 of those with asthma. Latent periods of work with animals before symptoms appeared varied from 0.5 to 12 years. Also 148 individuals were studied during their first year of work with animals (prospective study). Symptoms developing during the year were reported by 15%, asthma by 2%. IgE antibody levels to rat urine were raised in 40% of affected and 6% of the unaffected individuals but there was no significant correlation between symptoms and either antibody levels or positive skin tests. Allergic symptoms developing during the first year of postemployment were, on the whole, much milder than those seen in the retrospective study. A tentative conclusion is that most individuals who become allergic to laboratory animals develop the condition in a mild form during their first year of employment but it appears probable that atopic individuals, although having an equal chance of developing allergy as compared with non-atopic individuals, may eventually progress to a more severe form of the disease.     

Allergy to laboratory animals: a retrospective and a prospective study

Twenty four volunteers who had been allergic to laboratory animals for some years were examined by means of a questionnaire paying particular attention to symptoms associated with rats and by serological and skin tests with extracts of rat urine (retrospective study). Nasal and eye symptoms were reported by 21 and 16 individuals respectively: 13 had asthma. Positive skin tests and high levels of specific IgE antibody to rat urine extract were found in 17 of the more severely affected individuals and this group included 12 of those with asthma. Latent periods of work with animals before symptoms appeared varied from 0.5 to 12 years. Also 148 individuals were studied during their first year of work with animals (prospective study). Symptoms developing during the year were reported by 15%, asthma by 2%. IgE antibody levels to rat urine were raised in 40% of affected and 6% of the unaffected individuals but there was no significant correlation between symptoms and either antibody levels or positive skin tests. Allergic symptoms developing during the first year of postemployment were, on the whole, much milder than those seen in the retrospective study. A tentative conclusion is that most individuals who become allergic to laboratory animals develop the condition in a mild form during their first year of employment but it appears probable that atopic individuals, although having an equal chance of developing allergy as compared with non-atopic individuals, may eventually progress to a more severe form of the disease.     

Prevalence of Occupational Allergy in Medical Researchers Exposed to Laboratory Animals

Allergy to laboratory animals is a well known occupational hazard and remains a health concern for individuals in contact with lab animals. This study evaluates the prevalence of allergy symptoms among medical researchers exposed to laboratory animals. We analyzed data from a cross-sectional survey, involving subjects (n=169, 21–59 yr), working in Kochi Medical School, Japan. They were asked to fill out a questionnaire to evaluate symptoms related to contact with laboratory animals. The overall response rate was 86.2%. The prevalence of laboratory animal allergy was 17.6%. The symptoms most reported were allergic rhino-conjunctivitis and asthma. A small number of the subjects received education on the allergy issue and 62.5% of subjects with an allergy to laboratory animals claimed to have atopy. Protection from animal allergens should be a high priority for institutions using lab animals; providing continuous education to animal handlers would be meaningful to reduce and control exposure.     

Pregnant women as a reservoir of undetected sexually transmitted diseases in rural South Africa: implications for disease control.

OBJECTIVES: This study was undertaken to determine the prevalence of sexually transmitted diseases (STDs) in pregnant women in rural South Africa and to determine the value of using abnormal urogenital symptoms to identify infected women. METHODS: This was a cross-sectional study of 327 patients attending prenatal clinics. RESULTS: Of the 271 women with complete data, 141 (52%) had at least 1 STD and 49 (18%) had more than 1. Abnormal symptoms were common (n = 225; 83%), but associations were weak, and the positive predictive value of different symptoms for infection ranged from 2% to 54%. CONCLUSIONS: Most STDs in rural South African women remain undetected and untreated. As the scope for laboratory diagnosis in resource-poor settings is limited, presumptive treatment of pregnant women and their partners may be a cost-effective option to reduce transmission of STDs and HIV infection.     

Formaldehyde exposure levels and serum antibodies to formaldehyde-human serum albumin of Korean medical students

In our study, we estimated formaldehyde exposure levels of Korean medical students during their cadaver dissection practice hours. In addition, we examined the prevalence rates of formaldehyde-specific immunoglobulin E or immunoglobulin G antibodies and compared the results with the symptoms the students experienced as a result of formaldehyde exposure. There were 167 Korean medical students (i.e., subjects) aged 23.8+/-2.5 y (mean+/-standard deviation) and a control group of 67 premedical students aged 20.1+/-2.8 y (mean+/-standard deviation). Concentrations of formaldehyde in the cadaver dissection practice laboratory ranged from 0.194 to 11.245 mg/m3 (3.736+/-3.478 mg/m3 [mean+/-standard deviation]). Students reported by self-administered questionnaires that eye soreness (92.8%) and lacrimation (74.9%) were the most common symptoms they experienced during the laboratory sessions. One (0.6%) of the 167 medical students had a history of wheezing during dissection. Fourteen (8.4%) had specific immunoglobulin G antibody, but none had specific immunoglobulin E antibody. These results suggest that (a) Korean medical students are exposed to formaldehyde at a relatively high levels in their dissection practice hours, (b) specific immunoglobulin G is not related to adverse eye or respiratory symptoms, and (c) specific immunoglobulin E is rarely induced as a result of exposure to formaldehyde.     

Cross-contamination of clinical specimens with Bacillus anthracis during a laboratory proficiency test--Idaho, 2006

On July 18, 2006, the Utah Department of Health notified epidemiologists at the Idaho Department of Health and Welfare that Bacillus anthracis, the causative agent for anthrax, had been isolated from a patient. On the same day, the Idaho epidemiologists were notified by the Idaho Bureau of Laboratories of a specimen from a second patient received for anthrax testing. The two reports resulted briefly in alerts to the Federal Bureau of Investigation (FBI) and precautionary treatment of one of the patients for anthrax. Subsequent investigation revealed that, during July 2006, the Idaho Bureau of Laboratories had been conducting a sentinel laboratory proficiency testing exercise among Idaho's hospital laboratories. The exercise included specimens with the Sterne strain of B. anthracis, a nonvirulent strain. Subsequent laboratory testing of the two patient isolates detected the Sterne strain of B. anthracis; neither patient had signs or symptoms consistent with B. anthracis infection. Further investigation revealed that the Idaho hospital laboratories that tested the two specimens had been conducting the laboratory proficiency testing exercise simultaneously, but the Idaho epidemiologists were not aware of the exercise. The two specimens had become cross-contaminated with B. anthracis in the laboratories. The findings in this report underscore the need to follow proper laboratory practices to minimize cross-contamination. In addition, to guard against false reports of anthrax, public health epidemiologists who monitor reportable diseases should be notified of upcoming proficiency testing of high-priority bioterrorism agents.     

Epilepsy, disturbances of behavior and consciousness in presence of normal thyroxine levels: still, consider the thyroid gland

Three patients, one man aged 51 years, and two women aged 49 and 52 years, had severe fluctuating and progressive neurological and psychiatric symptoms. All three had normal thyroxine levels but elevated thyroid stimulating hormone levels and positive thyroid antibodies. Based on clinical, laboratory, MRI and EEG findings they were eventually diagnosed with Hashimoto's encephalopathy, associated with Hashimoto thyroiditis. Treatment with prednisone in addition to thyroxine suppletion resulted in a remarkable remission of their neuropsychiatric symptoms. The disease is probably under-recognized.