Occupational Rhinitis

Occupational rhinitis is nasal inflammation with congestion, sneezing, itching and rhinorrhea caused by agents in the working environment, not by stimuli outside the workplace. It is probably as frequent as occupational asthma, which it commonly precedes. Workers with sensitizer-induced rhinitis have about a 3-fold higher risk of developing occupational asthma, so detection offers a chance to prevent lung disease.

Types

• Allergic: IgE-mediated to high molecular weight agents (flour, enzymes, latex, laboratory animal allergens, grain dust, storage mites) or non-IgE mediated to low molecular weight agents (isocyanates, anhydrides, platinum salts, persulfates, wood dust, glutaraldehyde)
• Irritant (non-allergic): acids, chlorine, solvents and dusts, either from a single massive exposure or repeated lower exposures

Risk is highest in bakers, laboratory workers, healthcare workers, woodworkers, farmers and hairdressers. Atopy raises the risk for high molecular weight agents. Symptoms usually appear within the first year of exposure for high molecular weight agents. Complications: occupational asthma, chronic sinusitis, reduced sleep and productivity, and job loss.

• Nasal blockage, rhinorrhea, sneezing and itching that begin or worsen at work and improve away from work
• Ocular itching and tearing, and loss of smell in some
• Nocturnal symptoms after the shift in delayed reactions
• Red flags: wheeze or cough (assess for asthma), unilateral symptoms or bleeding (exclude structural disease), and persistent loss of smell

1. History linking symptoms to the workplace, with details of tasks and agents.
2. Nasal examination (anterior rhinoscopy and endoscopy): pale or hyperemic mucosa, turbinate swelling, polyps and secretions.
3. Skin prick testing or specific IgE for suspected high molecular weight agents.
4. Objective measurement at work versus away from work: peak nasal inspiratory flow, acoustic rhinometry, nasal lavage cell counts (eosinophils) and nasal symptom scores.
5. Specific nasal provocation challenge in a specialist center, with measurement of symptoms, nasal volume or resistance, and inflammatory markers.
6. Spirometry and methacholine challenge or serial peak flow in every patient, since asthma frequently coexists.
7. Exclusion of other causes: non-occupational allergic rhinitis, vasomotor rhinitis, infection and drug-induced rhinitis.

Differentials: seasonal or perennial allergic rhinitis, non-allergic rhinitis, rhinosinusitis, nasal polyposis, drug-induced rhinitis and structural abnormality.

1. Exposure control: remove the worker from the agent when allergic sensitization is proved. When complete removal is not possible, use local exhaust ventilation, enclosure, substitution of the agent and respiratory protection.
2. Intranasal corticosteroid: fluticasone furoate 27.5 micrograms, 2 sprays in each nostril once daily, or mometasone furoate 50 micrograms, 2 sprays in each nostril once daily, for at least 2 to 4 weeks.
3. Intranasal antihistamine: azelastine 137 micrograms, 1 spray in each nostril twice daily.
4. Oral antihistamine: bilastine 20 mg orally once daily, or loratadine 10 mg once daily, for sneezing and itching.
5. Nasal saline irrigation: 150 to 240 mL of isotonic saline in each nostril once or twice daily to remove allergens and secretions.
6. Additional treatment: montelukast 10 mg orally once daily at night for refractory symptoms, and ipratropium bromide 0.03% nasal spray, 2 sprays in each nostril 2 to 3 times daily for persistent watery discharge.
7. Allergen immunotherapy can be considered for a limited number of agents when avoidance is not feasible (for example certain animal allergens).
8. Surveillance: workers with occupational rhinitis should be monitored for asthma with spirometry every 6 to 12 months.
9. Notification and compensation, and redeployment support.

Follow-up at 4 to 6 weeks, then yearly. Counsel on early reporting of cough or wheeze.