Allergy to orthopedic metal implants — A prospective study

Objectives

Evaluation of the allergenic properties of the metal knee or hip joint implants 24 months post surgery and assessment of the relation between allergy to metals and metal implants failure.

Materials and Methods

The study was conducted in two stages. Stage I (pre-implantation) — 60 patients scheduled for arthroplasty surgery. Personal interview, dermatological examination and patch testing with 0.5% potassium dichromate, 1.0% cobalt chloride, 5.0% nickel sulfate, 2.0% copper sulfate, 2.0% palladium chloride, 100% aluminum, 1% vanadium chloride, 5% vanadium, 10% titanium oxide, 5% molybdenum and 1% ammonium molybdate tetrahydrate were performed. Stage II (post-surgery) — 48 subjects participated in the same procedures as those conducted in Stage I.

Results

Stage I — symptoms of “metal dermatitis” were found in 21.7% of the subjects: 27.9% of the females, 5.9% of the males. Positive patch test results were found in 21.7% of the participants, namely to: nickel (20.0%); palladium (13.3%); cobalt (10.0%); and chromium (5.9%). The allergy to metals was confirmed by patch testing in 84.6% of the subjects with a history of metal dermatitis. Stage II — 10.4% of the participants complained about implant intolerance, 4.2% of the examined persons reported skin lesions. Contact allergy to metals was found in 25.0% of the patients: nickel 20.8%, palladium 10.4%, cobalt 16.7%, chromium 8.3%, vanadium 2.1% Positive post-surgery patch tests results were observed in 10.4% of the patients. The statistical analysis of the pre- and post-surgery patch tests results showed that chromium and cobalt can be allergenic in implants.

Conclusions

Metal orthopedic implants may be the primary cause of allergies. that may lead to implant failure. Patch tests screening should be obligatory prior to providing implants to patients reporting symptoms of metal dermatitis. People with confirmed allergies to metals should be provided with implants free from allergenic metals.     

Evaluation of Mycobacterium tuberculosis Early Secreted Antigenic Target 6 Recombinant Protein as a Diagnostic Marker in Skin Test

Objectives

Tuberculosis (TB) is the leading infectious disease in the developing world. Delayed-type hypersensitivity skin test diagnoses TB using tuberculin purified protein derivative (PPD), but this test is incapable of distinguishing Mycobacterium tuberculosis (MTB) infection from bacillus Calmette–Guérin (BCG) vaccination or an infection caused by nontuberculous mycobacteria (NTM). This study was performed to evaluate the use of recombinant early secretory antigenic target 6 (rESAT-6), a secretory protein found only in MTB, Mycobacterium bovis, and few other mycobacterial species, as a skin marker for MTB in guinea pigs.

Methods

We prepared recombinant MTB ESAT-6 and evaluated its use as a specific antigen for MTB in guinea pigs.

Results

Our results show that the purified MTB rESAT-6 antigen is capable of inducing a positive reaction only in guinea pigs sensitized to MTB. No such reaction was observed in the animals sensitized to M. bovis, BCG vaccination, or NTM (Mycobacterium avium).

Conclusion

Our study results confirm that the ESAT-6 antigen is more specific to MTB infection than PPD and could be used in more specific skin tests for detection of MTB in large animals and in humans.     

Occupational allergic and irritant contact dermatitis in workers exposed to polyurethane foam

Objectives

To evaluate sensitization to chemicals present in work environment after an outbreak of contact dermatitis in workers of vehicle equipment factory, exposed to polyurethane foam, based on 4,4′-diphenylmethane diisocyanate (MDI).

Material and Methods

From among 300 employees, 21 individuals reporting work-related skin and/or respiratory tract symptoms underwent clinical examination, patch testing, skin prick tests, spirometry and MDI sIgE measurement in serum. Patch tests included isocyanates series, selected rubber additives, metals, fragrances, preservatives, and an antiadhesive agent.

Results

Clinical examination revealed current eczema in the area of hands and/or forearms in 10 workers. Positive patch test reactions were found in 10 individuals, the most frequent to diaminodiphenylmethane and 4-phenylenediamine (7 persons). Reactions to an antiadhesive agent were assessed as irritant (5 workers). Except for sensitization to common aeroallergens, no significant abnormalities were found in the remaining tests. Occupational allergic contact dermatitis was diagnosed in 7 workers, irritant contact dermatitis in 10 and coexisiting allergic and irritant contact dermatitis in 3 workers.

Conclusions

In workers manufacturing products from polyurethane foam, attention should be paid to the risk of developing contact dermatitis. Skin problems in our study group were attributable probably to insufficient protection of the skin.     

Ten years incidence of natural rubber latex sensitization and symptoms in a prospective cohort of health care workers using non-powdered latex gloves 2000–2009

Objectives

To assess the incidence of sensitization and gloves-related symptoms in 10-year follow-up in a group of health care workers (9,660 person-years) using non-powdered latex gloves from 2000 to 2009 and to examine related factors.

Materials and methods

We studied 2,053 health care workers in Trieste Hospitals by means of skin prick test for latex extract, patch tests and medical examinations. We report the incidence of latex sensitization among workers using non-powdered latex gloves.

Results

The incidence of latex sensitization, rhinitis, asthma, urticaria, irritant and allergic contact dermatitis were 1.0; 0.12; 0.21; 0.72; 2.39 and 2.50 cases per 1,000 person-years, respectively. Respiratory symptoms and urticaria were positively related with latex sensitization (OR = 8.0; 95 % CL 1.27–48.6), with common allergic respiratory symptoms (OR = 4.19; 95 % CL 1.04–16.8) and with familial atopy (OR = 4.47; 95 % CL 1.1–17.9).

Conclusion

The incidence of latex sensitization and latex-related symptoms were very low but subjects with allergic symptoms related to common allergens are at higher risk. The use of non-latex gloves is suggested for them.     

Immunological determinants in a murine model of toluene diisocyanate-induced asthma

Objectives

Diisocyanates (DIC) are highly reactive, low-molecular-weight chemicals which are the leading cause of occupational asthma (OA). The aim of the study was to analyze certain aspects of the pathogenesis of allergic inflammation in the airways induced by toluene diisocyanate (TDI) in an experimental model in mice.

Materials and Methods

The experiment was carried out on 50 female BALB/cJ/Han/IMP mice, which were exposed by inhalation (intranasal and in the inhalation chamber) to toluene diisocyanate (2,4-TDI). After the experiment, the bronchoalveolar lavage fluid (BALF) was collected from the animals, and the composition of the induced inflammatory cells, and the concentrations of certain cytokines (IL-4, IL-5, TNF-α) were evaluated.

Results

The total number of cells in BALF of the examined group of mice was significantly higher compared to the control mice. There was also a significant increase in neutrophils and eosinophils in the study group compared to the controls. The number of lymphocytes and macrophages did not differ significantly between the two groups. A statistically significant increase in the level of TNF-α was shown to occur in the group exposed to toluene diisocyanate in comparison to the control group. The concentration of IL-4 increased in the study group, compared to the control one, but the differences did not reach the level of significance, p > 0.05. Such difference was not observed for IL-5.

Conclusions

We developed a murine model of TDI-induced asthma which caused the influx of inflammatory cells like eosinophils and neutrophils in the bronchoalveolar lavage fluid (BALF) in the TDI-treated mice. The increase of the concentration of some proinflammatory cytokines (TNF-α, IL-4) in BALF from the exposed mice was also observed.     

Prävalenz von Erkrankungen und Beschwerden bei Studierenden in NRW

Background

The health status of university students has rarely been investigated in Germany.

Method

The aim of the student health survey was to collect self-reported information on health status as a database for health promotion for this target group.

Results

One third of the respondents reported allergic coryza. Complaints such as concentration difficulties and restlessness appeared even more often (around 40% of the students).

Discussion

The high prevalence of allergic diseases as well as health complaints call for target group-specific health promotion programmes.     

Outcome of oral provocation test in egg-sensitive children receiving semi-fat hard cheese Grana Padano PDO (protected designation of origin) containing, or not, lysozyme

Purpose

Lysozyme, obtained from egg white, is a potential food allergen used in the dairy industry to prevent late blowing of the loaf caused by the outgrowth of clostridial spores (Cl. butyricum and Cl. tyrobutyricum) during cheese aging. The aim of this study was to evaluate the possible correlation between egg protein allergy in pediatric age and sensitization to egg lysozyme, used for the preparation of Grana Padano cheese.

Methods

The tolerability of Grana Padano cheese has been evaluated in pediatric patients allergic to egg proteins through an oral provocation test with increasing amounts of cheese containing, or not, lysozyme at 12 and 24 months of aging.

Results

When lysozyme-sensitized children received 12-months aged and lysozyme-containing cheese, several immediate and late adverse reactions such as itching, abdominal pain, vomiting, nausea, dermatitis, rhinitis, bronchial asthma, urticaria, and angioedema were seen in 5 out of 21 subjects; only 1 out of 21 children showed an adverse reaction after challenge with 24-months-ripened lysozyme-containing cheese.

Conclusions

There is a possible relationship between the severity of allergic reactions and the lysozyme-specific IgE level in blood. In particular vomiting, hypotension, and abdominal pain were present when IgE level was higher than 7 kU/L. A ripening time of 24 months may reduce allergy problems when lysozyme-containing cheese is given to sensitized subjects, probably due to the hydrolysis of antigenic epitopes during aging.     

Work-related airway symptoms, nasal reactivity and health-related quality of life in female hairdressers: a follow-up study during exposure

Objectives

Hairdressers often complain of work-related rhinitis (WR). They are infrequently sensitized to persulphates. The cause and mechanism of the symptoms and the effects on their health-related quality of life (HRQoL) remains unclear. The objectives were to follow female hairdressers with WR mainly from bleaching powder regarding nasal reactivity to persulphate and to evaluate symptoms, HRQoL and inflammatory markers in nasal lavage during a working period after vacation and compared with hairdressers without symptoms and pollen allergic women.

Methods

Skin prick tests to persulphate were performed in the hairdressers. Participants kept a diary of symptoms and of work tasks (hairdressers only). They completed HRQoL questionnaires. Eosinophil cationic protein (ECP) in nasal lavage fluid was examined. The symptomatic hairdressers performed nasal challenges with persulphate before and after the exposure.

Results

Skin prick tests were negative. Although the nasal reactivity to persulphate did not change a steady increase in nasal symptoms, especially blockage, and in ECP was noticed in the symptomatic hairdressers. The HRQoL deteriorated in the symptomatic hairdressers indicating an effect on their working situation and daily life. The atopics had more, but varying symptoms (itching, sneezing and secretion).

Conclusions

The difference in the clinical picture between the symptomatic hairdressers and the pollen allergic women, the increase in symptoms and ECP in the nasal lavage support the view that a sensitization to hairdresser chemicals by a mechanism not yet understood is operating. The deterioration of the HRQoL in the symptomatic hairdressers indicates a considerable effect on their life.     

Allergens causing occupational asthma: an evidence-based evaluation of the literature

Purpose

The aim of this work is to provide an evidence-based evaluation and overview of causative substances in order to improve disease management.

Methods

We conducted a database search with MEDLINE via PubMed, screened reference lists of relevant reviews and matched our findings with a list of agents denoted as “may cause sensitisation by inhalation” by the phrase H334 (till 2011 R42). After exclusion of inappropriate publications, quality of the selected studies was rated with the Scottish Intercollegiate Guideline Network (SIGN) grading system. The evidence level for each causative agent was graded using the modified Royal College of General Practitioners (RCGP) three-star system.

Results

A total of 865 relevant papers were identified, which covered 372 different causes of allergic work-related asthma. The highest level achieved using the SIGN grading system was 2++ indicating a high-quality study with a very low risk of confounding or bias and a high probability of a causal relationship. According to the modified RCGP three-star grading system, the strongest evidence of association with an individual agent, profession or worksite (“***”) was found to be the co-exposure to various laboratory animals. An association with moderate evidence level (“**”) was obtained for α-amylase from Aspergillus oryzae, various enzymes from Bacillus subtilis, papain, bakery (flour, amylase, storage mites), western red cedar, latex, psyllium, farming (animals, cereal, hay, straw and storage mites), storage mites, rat, carmine, egg proteins, atlantic salmon, fishmeal, norway lobster, prawn, snow crab, seafood, trout and turbot, reactive dyes, toluene diisocyanates and platinum salts.

Conclusion

This work comprises the largest list of occupational agents and worksites causing allergic asthma. For the first time, these agents are assessed in an evidence-based manner. The identified respiratory allergic agents or worksites with at least moderate evidence for causing work-related asthma may help primary care physicians and occupational physicians in diagnostics and management of cases suffering from work-related asthma. Furthermore, this work may possibly provide a major contribution to prevention and may also initiate more detailed investigations for broadening and updating these evidence-based evaluations.     

Gesundheitliche Situation und Gesundheitsverhalten von Studierenden

Background

The subject of health of university students gains importance, but their health status has rarely been investigated in Germany.

Method

To get a representative sample, the study was conducted by inviting all students of Esslingen University of Applied Science to participate in this study.

Results

The most frequently reported symptoms were concentration difficulties (53.1?%) and agitation (51.0?%). The most frequent disease is allergic coryza. Nearly one fifth of the students have musculoskeletal disorders.

Discussion

The results of previous studies can be confirmed. Based on the identified risks and potentials, Esslingen University could initiate further steps in health promotion.     

Provocation of respiratory allergy in guinea pigs following inhalation of free toluene diisocyanate

An animal exposure experiment which simulated a workplace exposure situation was made to compare toluene diisocyanate (TDI) concentrations which resulted in antibody production with those which elicited pulmonary responses. Groups of guinea pigs were exposed to inhaled TDI from 0.02 to 1.0 ppm (g/g) for 3 h/day on 5 consecutive days. Three weeks later the animals were challenged with 0.02 ppm of free TDI for 15 min. TDI specific antibodies and pulmonary responses were evaluated. Specific antibody production showed a linear correlation to TDI concentration at induction. Most of the animals exposed to TDI levels above 0.2 ppm displayed significant pulmonary responses, but no correlation was found between TDI concentration at induction and the intensity of pulmonary response upon challenge to free TDI. These results indicated that there was a threshold concentration of 0.02 ppm TDI for antibody production and for the development of pulmonary response. It was also found that exposure to TDI at a level lower than its threshold concentration for sensitization may elicit a response in previously sensitized individuals.     

Experimental exposure of healthy subjects with emissions from a gas metal arc welding process—part II: biomonitoring of chromium and nickel

Objectives

The objective of this study was to investigate whether there is a relationship between the external exposure dose of chromium and nickel caused by a metal active gas welding process with a solid high-alloyed steel welding wire and inner exposure of subjects. In order to perform welding fume exposure under controlled and standardized conditions, the investigations were conducted in the “Aachen Workplace Simulation Laboratory”.

Methods

To perform biological monitoring of chromium and nickel, blood and urine samples of 12 healthy male non-smokers who never worked as welders were collected before and after a 6-h exposure to ambient air (0 mg/m³) and to welding fumes of a metal active gas welding process once with a concentration of the welding fume of 1 mg/m³ and once with a concentration of 2.5 mg/m³.

Results

Although the internal exposure to chromium and nickel in this study was comparatively low, the subjects showed significantly increased concentrations of these metals in urine after exposure to welding fume compared to the values at baseline. Moreover, the observed increase was significantly dose dependent for both of the substances.

Conclusion

For the biological monitoring of chromium and nickel in urine of subjects exposed to welding fumes, a dependency on exposure dose was seen under standardized conditions after a single exposure over a period of 6 h. Thus, this study contributes to a better understanding of the relationship between ambient and biological exposures from welding fumes and provides a good basis for evaluating future biological threshold values for these metals in welding occupation.     

Occupational skin hazards and prevalence of occupational skin diseases in shoe manufacturing workers in Indonesia

Purpose

Shoe manufacturing workers are exposed daily to an extensive range of potential physical and chemical occupational hazards. Shoe manufacturing in Indonesia is one of the industrial sectors that has shown sustained growth amongst the newly industrialized countries (NICs). In this study, we investigated the possible potential exposure of the workers to physical and occupational hazards and determined the prevalence of occupational skin diseases at a shoe manufacturing factory in Indonesia.

Methods

A cross-sectional study on the observation of the working process and an inventory and risk assessment of exposure to the chemicals used. Classification of chemicals as potential sensitizers/irritants and qualitative assessments of these chemicals were done. Workers were examined and interviewed using the Nordic Occupational Skin Questionnaire-2002/LONG.

Results

The risk of Occupational skin diseases (OSD) at the shoe factory was mainly related to the exposure of the workers’ skin to potential physical and chemical hazards in hot and humid environmental conditions. From a total of 514 workers, 8.5 % reported current OSD and 4.8 % reported a history of OSD. Occupational skin diseases were diagnosed in 29 % of the workers by dermatologists and 7.6 % had an occupational contact dermatitis (OCD). Of the 39 workers with contact dermatitis, 33 consented to being patch tested, 14 (3 %) workers showed a positive results and considered as having an occupational allergic contact dermatitis (OACD) and 25 (4.9 %) had an occupational irritant contact dermatitis (OICD).

Conclusion

We observed a repeated and prolonged exposure of the workers to numerous physical and chemical skin hazards at this factory.     

Maternal Bisphenol A Exposure Promotes the Development of Experimental Asthma in Mouse Pups

Background

We recently reported that various environmental estrogens induce mast cell degranulation and enhance IgE-mediated release of allergic mediators in vitro.

Objectives

We hypothesized that environmental estrogens would enhance allergic sensitization as well as bronchial inflammation and responsiveness. To test this hypothesis, we exposed fetal and neonatal mice to the common environmental estrogen bisphenol A (BPA) via maternal loading and assessed the pups’ response to allergic sensitization and bronchial challenge.

Methods

Female BALB/c mice received 10 μg/mL BPA in their drinking water from 1 week before impregnation to the end of the study. Neonatal mice were given a single 5 μg intraperitoneal dose of ovalbumin (OVA) with aluminum hydroxide on postnatal day 4 and 3% OVA by nebulization for 10 min on days 13, 14, and 15. Forty-eight hours after the last nebulization, we assessed serum IgE antibodies to OVA by enzyme-linked immunosorbent assay (ELISA) and airway inflammation and hyperresponsiveness by enumerating eosinophils in bronchoalveolar lavage fluid, whole-body barometric plethysmography, and a forced oscillation technique.

Results

Neonates from BPA-exposed mothers responded to this “suboptimal” sensitization with higher serum IgE anti-OVA concentrations compared with those from unexposed mothers (p < 0.05), and eosinophilic inflammation in their airways was significantly greater. Airway responsiveness of the OVA-sensitized neonates from BPA-treated mothers was enhanced compared with those from unexposed mothers (p < 0.05).

Conclusions

Perinatal exposure to BPA enhances allergic sensitization and bronchial inflammation and responsiveness in a susceptible animal model of asthma.     

Occupational asthma caused by samba (Triplochiton scleroxylon) wood dust in a professional maker of wooden models of airplanes: A case study

Objectives

Wood dust is a known occupational allergen that may induce, in exposed workers, respiratory diseases including asthma and allergic rhinitis. Samba (obeche, Triplochiton scleroxylon) is a tropical tree, which grows in West Africa, therefore, Polish workers are rarely exposed to it. This paper describes a case of occupational asthma caused by samba wood dust.

Material and Methods

The patient with suspicion of occupational asthma due to wood dust was examined at the Department of Occupational Diseases and Clinical Toxicology in the Nofer Institute of Occupational Medicine. Clinical evaluation included: analysis of occupational history, skin prick tests (SPT) to common and occupational allergens, determination of serum specific IgE to occupational allergens, serial spirometry measurements, metacholine challenge test and specific inhalation challenge test with samba dust

Results

SPT and specific serum IgE assessment revealed sensitization to common and occupational allergens including samba. Spirometry measurements showed mild obstruction. Metacholine challenge test revealed a high level of bronchial hyperactivity. Specific inhalation challenge test was positive and cellular changes in nasal lavage and induced sputum confirmed allergic reaction to samba.

Conclusions

IgE mediated allergy to samba wood dust was confirmed. This case report presents the first documented occupational asthma and rhinitis due to samba wood dust in wooden airplanes model maker in Poland.     

Pulmonary function impairment and airway allergy among workers in traditional bakeries

Objectives

To assess the effect of exposure to flour dust on pulmonary function tests, prevalence of symptoms (respiratory, allergic/irritating) and parameters of allergic sensitization in terms of skin prick test, and bronchial hyper-responsiveness.

Material and Methods

43 bakers (with at least 2 years of occupational exposure) working at different bakeries in Ismailia city, Egypt; and 64 control subjects of comparable socio demographic characteristics were compared. All participants were subjected to an interview questionnaire, clinical chest examination, skin prick test, bronchial hyper-responsiveness test and measurements of pulmonary function parameters.

Results

All respiratory and allergic symptoms were more prevalent among bakers compared to the control group, with the highest odds ratio for allergic symptoms (OR = 6.9; p < 0.0001) and dyspnea (OR = 6.3; p = 0.0004). Bakers had a higher percentage of SPT positive results with statistically significant difference between the two groups (p < 0.0001). Bakers had lower observed values compared to the control group with statistically significant difference for FVC, FEV₁/FVC ratio, FEF_75%, and FEF_25–75% parameters.

Conclusion

The present study suggested that occupational exposure to flour dust may affect respiratory irritation and sensitization, and reduce the pulmonary function tests such as FVC, FEV₁, and FEV₁/FVC ratio and FEF_25–75%.     

Work-related respiratory symptoms among health centres cleaners: A cross-sectional study

Objectives

Several studies, mostly based on questionnaire-derived data, have shown an increased risk of allergic diseases, especially asthma, among cleaners. The risk factors and etiological mechanisms are still being investigated. Occupational exposure to various chemical and biological agents may induce specific sensitization and/or irritant effects. The aim of our study was to estimate the prevalence of work-related symptoms suggesting the presence of allergic disease reported by cleaners, and to relate them to the results of commercially available and standardized objective tests used for screening detection of occupational sensitization and chronic respiratory disorders.

Material and Methods

A cross-sectional study was performed among 142 Polish workers of cleaning service in their workplaces. A detailed questionnaire, skin prick tests to common allergens and chemicals used by these workers for cleaning purposes (chloramine T, chlorhexidine, formaldehyde, glutaraldehyde, benzalconium chloride), total and specific serum IgE antibodies to disinfectants and rest spirometry were performed in all the subjects.

Results

Fifty nine percent of all the subjects declared occurrence of at least 1 symptom suggesting allergic ailment during cleaning activities at work. Skin prick tests and specific serum IgE antibodies to disinfectants were negative in all the subjects. In 8 cases wheezing was detected during auscultation, but only in 5 of them obstructive pattern in rest spirometry was found.

Conclusions

Occupational allergic causation of symptoms among cleaners could be less likely than work-related symptoms associated with exacerbations of new-onset or pre-existing respiratory diseases. Therefore, in this group of workers, mainly the non-specific irritant impact of chemicals on airways should be taken into consideration.     

Occupational skin diseases in Czech healthcare workers from 1997 to 2009

Background

The healthcare sector ranked in second place among economic sectors in the Czech Republic, with about 11.4 % of all occupational diseases in 2009. Skin diseases constituted about 20 % of all occupational diseases.

Objectives

The aim of this study was to analyze the causes and trends in allergic and irritant-induced skin diseases in the healthcare sector.

Methods

The data concerning occupational skin diseases (Chapter IV of the Czech List of Occupational Diseases, non-infectious skin illnesses) in the healthcare sector were analyzed from the Czech National Registry of Occupational Diseases from 1997 until 2009. The trends in the total counts and most frequent causes were evaluated.

Results

During the past 13 years, a total of 545 skin diseases were acknowledged in healthcare workers. Allergic contact dermatitis was diagnosed in 464 (85 %), irritant contact dermatitis in 71 (13 %) and contact urticaria in 10 subjects (2 %). Ninety-five percent of the patients were females. The overall incidence in individual years varied between 1.0 and 2.9 cases per 10,000 full-time employees per year. Disinfectants were the most frequent chemical agents causing more than one third of all allergic skin diseases (38 %), followed by rubber components (32 %) and cleaning agents (10 %).

Conclusion

A general downward trend of diagnosed cases of occupational skin diseases in heath care workers in the Czech Republic over the past 13 years was demonstrated.     

Folate-deficiency induced cell-specific changes in the distribution of lymphocytes and granulocytes in rats

Objective

Folate (vitamin B₉) plays key roles in cell growth and proliferation through regulating the synthesis and stabilization of DNA and RNA, and its deficiency leads to lymphocytopenia and granulocytopenia. However, precisely how folate deficiency affects the distribution of a variety of white blood cell subsets, including the minor population of basophils, and the cell specificity of the effects remain unclear. Therefore, we examined the effects of a folate-deficient diet on the circulating number of lymphocyte subsets [T-lymphocytes, B-lymphocytes, and natural killer (NK) cells] and granulocyte subsets (neutrophils, eosinophils, and basophils) in rats.

Methods

Rats were divided into two groups, with one receiving the folate-deficient diet (FAD group) and the other a control diet (CON group). All rats were pair-fed for 8 weeks.

Results

Plasma folate level was dramatically lower in the FAD group than in the CON group, and the level of homocysteine in the plasma, a predictor of folate deficiency was significantly higher in the FAD group than in the CON group. The number of T-lymphocytes, B-lymphocytes, and NK cells was significantly lower in the FAD group than in the CON group by 0.73-, 0.49-, and 0.70-fold, respectively, indicating that B-lymphocytes are more sensitive to folate deficiency than the other lymphocyte subsets. As expected, the number of neutrophils and eosinophils was significantly lower in the FAD group than in the CON group. However, the number of basophils, the least common type of granulocyte, showed transiently an increasing tendency in the FAD group as compared with the CON group.

Conclusion

These results suggest that folate deficiency induces lymphocytopenia and granulocytopenia in a cell-specific manner.     

Lifetime allergic rhinitis prevalence among US primary farm operators: findings from the 2011 Farm and Ranch Safety survey

Purpose

Allergic rhinitis is associated with decreased quality of life, and reduced workplace performance and productivity. This study investigated the prevalence of lifetime allergic rhinitis and factors associated with allergic rhinitis among US primary farm operators.

Methods

The 2011 Farm and Ranch Safety Survey data collected from 11,210 active farm operators were analyzed. Survey respondents were determined to have lifetime allergic rhinitis based on a “yes” response to the question: “Have you ever been told by a doctor, nurse, or other health professional that you had hay fever, seasonal allergies, or allergic rhinitis?” Data were weighted to produce nationally representative estimates.

Results

An estimated 30.8% of the 2.1 million active farm operators had lifetime allergic rhinitis in 2011. The allergic rhinitis prevalence varied by demographic and farm characteristics. Farm operators with allergic rhinitis were 1.38 (95% CI 1.22–1.56) times more likely to be exposed to pesticides compared with operators with no allergic rhinitis. The association with pesticide exposure for allergic rhinitis and current asthma, and allergic rhinitis alone was statistically significant and greater than that for current asthma alone.

Conclusion

Certain groups of farm operators may be at increased risk of allergic rhinitis. Studies should further investigate the association of allergic rhinitis with specific pesticide exposure.