Hypersensitivity pneumonitis to phthalic anhydride: Case description and review of the literature.

Hypersensitivity pneumonitis (HP) is a rare, mostly occupational allergic disease of the lungs. There are many inhalable antigens that can cause HP. Most are organic dusts, rarely chemicals. A clinical case of HP is presented in a cable production worker with exposure to plasticizers who was initially diagnosed with idiopathic pulmonary fibrosis. The presence of specific IgG antibodies (sIgG) to phthalic anhydride in the patient's serum, together with reduced carbon monoxide diffusion capacity, hypoxemia at rest and on exertion, and the findings on computed tomography and histology, seemed to confirm the diagnosis of chronic HP due to phthalates, particularly as exposure to phthalate compounds at work was reported by the Technical Inspection Service. A review of the literature revealed that there is evidence of plasticizer alveolitis. While in four previous case reports phthalic anhydride was suspected as the cause of occupational HP because of work-related symptoms, we were able to detect sIgG to phthalic anhydride for the first time. This case illustrates that phthalates, which have rarely been described as triggers of HP, should be considered in cases of suspected occupational HP.