4-methyl-cis-hexahydrophthalic-anhydride and Rhinitis

Epoxy resin compounds (ERC) include a large number of chemicals, such as epoxy resins (ER), reactive diluents and hardeners. Many hardeners, e.g., aliphatic polyamines, are well-known sensitizers. Another type of ER hardeners are the phthalic anhydrides, such as methylhexahydrophthalic anhydride (MHHPA) and methyltetrahydrophthalic anhydride (MTHPA), which have been reported as causing immunologically-mediated respiratory diseases and contact urticaria, but not allergic contact dermatitis. Here, we present a horizontal boring-machine worker who developed allergic contact dermatitis, as well as allergic rhinitis and an immediate contact skin reaction from MHHPA. Patch testing with a dilution series of MHHPA in pet. elicited the following results: 2%, 1% and 0.5%, +2; 0.25% and 0.125%, + (3- to 6-day readings). An immunohistochemical and electron microscopic study also indicated that the patch test reactions were conventional-delayed allergic reactions. Interleukin 8 was observed in the epidermal cells, whereas interleukin 4 immunoreactivity was detected in the dermal cells. Immunoreactivity to-interleukin 5, granulocyte/macrophage-colophony stimulating factor (GM-CSF) or eosinophil cationic protein was not seen. In conclusion, the patient developed both Type I and Type IV allergy to MHHPA. The clinical data, patch test results, immunohistochemical and electron microscopic observations indicated that the MHHPA allergy detected by the patch test reaction was a conventional delayed-type hypersensitivity reaction. The patient also had an allergic patch test reaction to para-phenylenediamine and diaminodiphenylmethane, possibly representing occupational sensitization.

Topics: Allergens; Aniline Compounds; Blood Proteins; Dermatitis, Allergic Contact; Dermatitis, Occupational; Eosinophil Granule Proteins; Eosinophils; Epidermis; Epoxy Resins; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Hypersensitivity, Delayed; Hypersensitivity, Immediate; Immunohistochemistry; Inflammation Mediators; Interleukin-4; Interleukin-5; Interleukin-8; Male; Microscopy, Electron; Middle Aged; Patch Tests; Phenylenediamines; Phthalic Anhydrides; Respiratory Hypersensitivity; Rhinitis; Ribonucleases; Skin; Urticaria

Acid anhydrides are low-molecular-weight chemicals known to cause respiratory irritancy and allergy. Skin allergy has on rare occasions been reported. 2 workers contracted hives and itching on uncovered skin after 2 months exposure to methyltetrahydrophthalic anhydride (MTHPA) and methylhexahydrophthalic anhydride (MHHPA), to which they had airborne exposure. Later, the patients also developed conjunctivitis, rhinitis, sore throat, cough or asthma. In addition to MTHPA, 1 worker was also exposed to unsaturated polyester resin (UP). Both patients' immediate allergy to MTHPA and MHHPA was verified by positive prick tests to MTHPA and MHHPA, conjugated with human serum albumin (HSA), and positive radioallergosorbent tests (RASTs) to these anhydrides. On prick testing, both patients also reacted to a phthalic anhydride (PA)-HSA-conjugate and 1 of the patients to UP-HSA-conjugate. Specific immediate allergy to UP was shown by RAST. RAST inhibition with MTHPA, MHHPA and UP-resin conjugates confirmed IgE-mediated allergy and cross-reactivity between anhydrides. Our patients had developed airborne contact urticaria caused by phthalic anhydrides, in addition to respiratory allergy. Phthalic anhydride contained in the UP resin was possibly responsible for the immediate reaction of the skin.

Topics: Adult; Air Pollutants; Asthma; Dermatitis, Occupational; Female; Humans; Immunoglobulin E; Male; Occupational Exposure; Patch Tests; Phthalic Anhydrides; Rhinitis; Urticaria