Pulmonary illness as a consequence of occupational exposure to shrimp shell powder

Clinical Management of Seafood Allergy

Seafood plays an important role in human nutrition and health. A good patient workup and sensitive diagnostic analysis of IgE antibody reactivity can distinguish between a true seafood allergy and other adverse reactions generated by toxins or parasites contaminating ingested seafood. The 2 most important seafood groupings include the fish and shellfish. Shellfish, in the context of seafood consumption, constitutes a diverse group of species subdivided into crustaceans and mollusks. The prevalence of shellfish allergy seems to be higher than that of fish allergy, with an estimate of up to 3% in the adult population and fin fish allergy prevalence of approximately 1%. Clinical evaluation of the seafood-allergic patient involves obtaining a detailed history and obtaining in vivo and/or in vitro testing with careful interpretation of results with consideration of cross-reactivity features of the major allergens. Oral food challenge is useful not only for the diagnosis but also for avoiding unnecessary dietary restrictions. In this review, we highlight some of the recent reports to provide solid clinical and laboratory tools for the differentiation of fish allergy from shellfish allergy, enabling best treatment and management of these patients.

Work-related Symptoms and Asthma among Fish Processing Workers

After observing several clinical patients with respiratory symptoms, we initiated a questionnaire survey to assess prevalence of and predictors for asthma and work-related symptoms among workers in fish processing plants. A questionnaire with items on work conditions, work-related symptoms, and respiratory symptoms/diseases was sent to 916 fish processing workers, the 1836 licenced fishermen in Sweden, and 1965 controls; of those, 43%, 57%, and 53%, respectively, responded. Risks, hazard ratios (HRs), and prevalence ratios (PRs) were calculated with Cox regression, and 95% confidence intervals (CIs) were computed. The risk of asthma among fish filleting workers was increased during the years working in the fish processing industry when compared to the other fish processing workers and controls (HR 3.6, 95% CI 1.6-8.1, adjusted for atopy, gender, and ever smoking). The filleters had an increased PR for most of the work-related respiratory symptoms investigated. All fish processing workers had a higher PR for flu-like symptoms. Use of a pressure sprayer was identified as a risk for asthma and respiratory symptoms among both fish processing workers and controls. Filleters had changed work tasks because of respiratory symptoms more often (Fisher's exact test, p = 0.02) than other fish processing workers. In conclusion the fish filleters and pressure sprayer users reported more adult asthma and cough with phlegm compared to the other fish processing workers and controls. The use of pressure sprayers must be reduced and machinery should be completely encased to reduce workers' exposure to bioaerosols and its effects on the respiratory tract.

Exposure assessment in hypersensitivity pneumonitis: a comprehensive review and proposed screening questionnaire

Hypersensitivity pneumonitis is an immune-mediated inflammatory lung disease characterised by the inhalation of environmental antigens leading to acute and chronic lung injury. Along with suggestive clinical and radiological findings, history and timing of suspected antigen exposure are important elements for diagnostic confidence. Unfortunately, many diagnoses remain tentative and based on vague and imprecise environmental or material exposure histories. To date, there has not been a comprehensive report highlighting the frequency and type of environmental exposure that might lead to or support a more systematic approach to antigen identification. We performed a comprehensive literature review to identify and classify causative antigens and their associated environmental contexts or source materials, with emphasis on the extent of the supportive literature for each exposure type. Eligible publications were those that reported unique inciting antigens and their respective environments or contexts. A clinical questionnaire was then proposed based on this review to better support diagnosis of hypersensitivity pneumonitis when antigen testing or other clinical and radiological variables are inconclusive or incomplete.

Hypersensitivity pneumonitis: A fibrosing alveolitis produced by inhalation of diverse antigens

Hypersensitivity pneumonitis (HP) is a T_H1 lymphocyte-biased fibrosing alveolitis caused by antigens ranging from avian excreta, fungi, thermophilic bacteria, and protozoa to reactive chemicals found in the workplace. Mimicking a viral syndrome, acute exposures to inciting antigens cause abrupt onset of nonproductive cough, dyspnea, and chills with arthralgias or malaise usually from 4 to 8 hours later so that the temporal relationship between antigen exposure and symptoms might be unsuspected. The histology of HP reveals prominent lymphocyte infiltrates that thicken the alveolar septa with poorly formed granulomas or giant cells. Bronchoalveolar lavage fluid demonstrates greater than 20% lymphocytes in nearly all patients. Abnormalities on high-resolution computed tomographic examinations range from nodular centrilobular opacities in acute/subacute disease to increased reticular markings and honeycombing fibrosis, which typically are predominant in the upper lobes, in patients with advanced disease. Descriptors include "mosaic" attenuation and ground-glass opacities. Repeated episodes can result in nodular pulmonary infiltrates and suspected nonspecific interstitial pneumonia or idiopathic pulmonary fibrosis. Clinicians require a high level of suspicion to make an early diagnosis of HP before extensive pulmonary fibrosis or restrictive lung disease has occurred.