Work-related allergies to storage mites in Parma (Italy) ham workers

OBJECTIVES: To investigate the role of storage mites in the development of allergic diseases among ham production workers, and to search for early alterations in lung function tests and early inflammation markers in exhaled air. Respiratory allergies due to storage mites have been reported in people with various occupations but, although such mites are unavoidable when curing ham, there are no published data concerning ham production workers. SETTING: Secondary care. DESIGN: Experimental cross-sectional study. PARTICIPANTS: 220 participants (110 ham production workers and 110 controls) were recruited. PRIMARY AND SECONDARY OUTCOME MEASURES: Workers answered a medical questionnaire, and underwent spirometry and fraction of exhaled nitric oxide at 50 mL/s (FeNO50) measurements. Those with allergic symptoms also underwent skin prick tests to determine their sensitisation to airborne allergens. A methacholine test was performed in symptomatic participants when spirometry was normal to assess airways hyper-responsiveness. RESULTS: Symptomatic storage mite sensitisation was observed in 16 workers (14.5%) (rhinoconjunctivitis in 15 (63%) and asthma in (4%)) and 2 controls (1.8%; p=0.001). Higher FeNO50 values in exposed symptomatic workers compared with healthy control participants (34.65±7.49 vs 13.29±4.29 ppb; p<0.001) suggested bronchial and nasal involvement, although their lung function parameters were normal. Regardless of exposure, a FeNO50 value of 22.5 ppb seems to be 100% sensitive and 99.4% specific in distinguishing allergic and non-allergic participants. Multivariate analysis of FeNO50 values in the symptomatic participants showed that they were positively influenced by IgE-mediated allergy (p=0.001) and reported symptom severity (p=0.041), and negatively by smoking status (p=0.049). CONCLUSIONS: Ham processing workers, as well as workers involved in any meat processing work that includes curing, should be informed about the occupational risk of sensitisation to mites

Immune Response to Mycobacterium tuberculosis Infection in the Parietal Pleura of Patients with Tuberculous Pleurisy

The T lymphocyte-mediated immune response to Mycobacterium tuberculosis infection in the parietal pleura of patients with tuberculous pleurisy is unknown. The aim of this study was to investigate the immune response in the parietal pleura of tuberculous pleurisy compared with nonspecific pleuritis. We have measured the numbers of inflammatory cells particularly T-cell subsets (Th1/Th2/Th17/Treg cells) in biopsies of parietal pleura obtained from 14 subjects with proven tuberculous pleurisy compared with a control group of 12 subjects with nonspecific pleuritis. The number of CD3+, CD4+ and CCR4+ cells and the expression of RORC2 mRNA were significantly increased in the tuberculous pleurisy patients compared with the nonspecific pleuritis subjects. The number of toluidine blue+ cells, tryptase+ cells and GATA-3+ cells was significantly decreased in the parietal pleura of patients with tuberculous pleurisy compared with the control group of nonspecific pleuritis subjects. Logistic regression with receiver operator characteristic (ROC) analysis for the three single markers was performed and showed a better performance for GATA-3 with a sensitivity of 75%, a specificity of 100% and an AUC of 0.88. There was no significant difference between the two groups of subjects in the number of CD8, CD68, neutrophil elastase, interferon (IFN)-γ, STAT4, T-bet, CCR5, CXCR3, CRTH2, STAT6 and FOXP3 positive cells. Elevated CD3, CD4, CCR4 and Th17 cells and decreased mast cells and GATA-3+ cells in the parietal pleura distinguish patients with untreated tuberculous pleurisy from those with nonspecific pleuritis

[Interpretative strategies of lung function tests: obstructive pattern]

INTRODUCTION: Periodic spirometric assessment is critical in the health surveillance of workers who are exposed to respiratory pollutants and plays a key role in the prevention of occupational lung diseases. OBJECTIVES: The aim of this review is to provide updates on the proper spirometry examination procedure and the criteria for data interpretation, in order to correctly diagnose obstructive impairment and longitudinal decline of pulmonary function. METHODS: A review of the most recent scientific literature was carried out focusing on those papers dealing with spirometric techniques, choice of reference values, and criteria for data interpretation. RESULTS: Over the years, the use of different diagnostic algorithms and reference values have led to poor clarity among users as well as diagnostic misclassifications. CONCLUSIONS: For spirometric data reliability it is mandatory to perform appropriate pulmonary function tests, make a correct selection of reference values and use updated interpretive criteria

Photomicrographs showing the parietal pleura (A, B) and positive control tonsil (C) immunostained for identification of STAT4+ cells (A–C).

<p>STAT4, positive cells are stained brown. Photomicrograph D shows the negative control slide of tonsil immunostained using normal nonspecific immunoglobulins. Results are representative of those from 14 patients with PLTB (A) and 12 patients with NSP (B). Original magnification: 400×. The scale bar represents 50 µm.</p

Photomicrographs showing the parietal pleura (A, B) and positive control tonsil (C and D) immunostained for identification of STAT6+ cells (A–C).

<p>STAT6+ cells are stained brown. Photomicrograph D shows negative control slide of tonsil immunostained using normal nonspecific immunoglobulins. Results are representative of those from 14 patients with PLTB (A) and 12 patients with NSP (B). Original magnification: 400×. The scale bar represents 50 µm.</p