xRead - September 2022

Wise et al.

Page 10

III.C.3. Occupational rhinitis— Occupational rhinitis is an inflammatory condition of the nasal mucosa, characterized by intermittent or persistent nasal congestion, sneezing, rhinorrhea, itching, and/or hypersecretion due to causes and conditions attributable to a particular work environment, and not to stimuli encountered outside the workplace. 84 Occupational rhinitis is considered a form of “work-related rhinitis,” which also encompasses work-exacerbated rhinitis, which is preexisting or concurrent rhinitis that is worsened by workplace exposures 84,85 (Fig. III.C.3). Occupational rhinitis may be allergic, consequent to exposure to a sensitizing high molecular (HMW) or low-molecular weight (LMW) compound acting through an immunological mechanism, and characterized by the presence of a latency period between beginning of exposure and symptom onset. Alternatively, occupational rhinitis may be non allergic, mediated by and irritant or non-immunological mechanism. Symptoms occur after single or multiple exposures to irritant compounds, and usually present without a latency period. Non-allergic occupational rhinitis resulting from a single exposure to a very high concentration of irritants is also referred as reactive upper airways dysfunction syndrome (RUDS). The most severe form of irritant-induced occupational rhinitis is corrosive rhinitis, which is characterized by permanent inflammation of the nasal mucosa sometimes associated with ulcerations and perforation of the nasal septum. 84,85 The results of cross-sectional studies in working groups show a wide range of prevalence of occupational rhinitis (3-87%), 86 lower prevalence for LMW-agent exposure, and higher prevalence for HMW-agent exposure. Examples of occupations at increased risk are reported in Table III.C.3. 87-98 Occupational rhinitis due to HMW-agents tend to be 3 times more prevalent than occupational asthma, 86 with which it is often associated (up to 92% of cases). 99 Occupational rhinitis and occupational asthma share etiologic agents and pathogenic mechanisms, 100 and can be considered in the broader context of the Unified Airway Disease model. 85,93,101,102 The severity of occupational rhinitis may also affect the severity of occupational asthma. 103 In a high proportion (20-78%) of workers exposed to sensitizers, work-related nasal symptoms tend to develop 5 to 6 months before the onset of bronchial symptoms. 84,86 Consequently, occupational rhinitis may be considered a marker of the likelihood of developing occupational asthma. The clinical presentation of occupational rhinitis is nonspecific. Nasal symptoms do not differ from those of non-occupational rhinitis. An occupational origin should be sought for all rhinitis of new onset in adults, especially in subjects employed in high-risk occupations (Table III.C.3). The diagnostic assessment first includes a thorough clinical and occupational history, aimed to investigate type of symptoms and work-relatedness, and to collect information on occupational exposure. Typical nasal symptoms are often accompanied by crust formation, sporadic epistaxis, olfaction impairment, or conjunctivitis, or are associated with pharyngeal, laryngeal, or bronchial symptoms (which should always be evaluated). The presence of a latency period between an occupational exposure and symptom onset suggests an allergic mechanism. Documentation of noxious compounds (sensitizers and irritants) in

Author Manuscript Author Manuscript Author Manuscript Author Manuscript

Int Forum Allergy Rhinol . Author manuscript; available in PMC 2020 June 10.