Respiratory allergy to nickel. Description of an atipical clinical case

BACKGROUND: Exposure to nickel sulphate, other than contact dermatitis, can potentially cause respiratory symptoms. Although few cases of occupational rhinitis and asthma are reported in literature, a prolonged exposure can determine sensitization and evolution to respiratory symptoms. OBJECTIVES: Clinical evaluation of a case of occupational rhinitis and asthma due to nickel sulphate. METHODS: A female worker, aged 43 years, has been occupationally exposed to nickel for 22 years. After 1 year she experienced asthma, apparently not work related. She treated the respiratory symptoms for many years, but a slow and progressive increase of the disease was observed. During the last five years a straight relationship between work and symptoms was observed. On-off test was positive. The diagnosis of occupational respiratory disease was based on the work-related symptoms and the specific nasal challenge test result. RESULTS: An early response was observed with nasal symptoms (score 4), increase of anterior nasal airflow resistance (33%), severe dyspnea, haematic eosinophilia, and fall in FEV-1 of 18%. CONCLUSIONS: The prolonged exposure to nickel determined impairment of respiratory function. Nasal challenge, more safe and useful than bronchial challenge, can be considered gold standard for the diagnosis of occupational rhinitis and asthma due to occupational allergens.