Delayed and immediate allergy caused by methylhexahydrophthalic anhydride

Association of p-phenylenediamine exposure with alterations of pulmonary function, pruritus and health-related quality of life in hair dye factory workers: a cross-sectional study

P-Phenylenediamine (PPD) is a common component of hair dye, which can cause skin contact allergy and asthma with impaired pulmonary function. However, the adverse effects of occupational exposure to different dose PPD was rarely mentioned. We recruited 124 workers from a hair dye factory to explore the association of occupational PPD exposure on pulmonary function, pruritus and health related quality of life (HRQL). We categorized exposure to PPD into 3 levels: lower exposure group (< 0.00001 mg/m³); middle exposure group (0.00001-0.00033 mg/m³); higher exposure group (0.00033-0.047 mg/m³). The HRQL and subjective pruritus of the workers were assessed by the short form 36 health survey (SF-36) and Visual analogue scale (VAS) of pruritus, respectively. In the high PPD-exposed group, the percentage of FEV1 (FEV1%) was lower in higher exposure group compared with lower exposure group. The FEV1/FVC was also lower in comparison to the higher exposure and middle exposure groups (p < 0.05). PPD levels were negatively correlated with vitality and mental health (p < 0.01). The structural equation model showed the positive effects of PPD on VAS level (β = 0.213, p < 0.001), and indicated partly negtive effects of PPD on total score of SF-36 (β = - 0.465, p = 0.002), respectively. Our results indicate that occupational exposure to PPD might be associated with pulmonary function impairment, poor HRQL, and subjective pruritus of the workers.

Contact allergy to epoxy hardeners

BACKGROUND

Diglycidylether of bisphenol A resin is the most important sensitizer in epoxy systems, but a minority of patients develop concomitant or solitary contact allergy to epoxy hardeners. At the Finnish Institute of Occupational Health, several in-house test substances of epoxy hardeners have been tested in a special epoxy compound patch test series.

OBJECTIVES

To analyse the frequency and clinical relevance of allergic reactions to different epoxy hardeners.

METHODS

Test files (January 1991 to March 2013) were screened for contact allergy to different epoxy hardeners, and the clinical records of patients with allergic reactions were analysed for occupation, concomitant allergic reactions, and exposure.

RESULTS

The most commonly positive epoxy hardeners were m-xylylenediamine (n = 24), 2,4,6-tris-(dimethylaminomethyl)phenol (tris-DMP; n = 14), isophorone-diamine (n = 12), and diethylenetriamine (n = 9). Trimethylhexamethylenediamine (n = 7), tetraethylenepentamine (n = 4), and triethylenetetramine (n = 2) elicited some reactions, although most patients were found to have no specific exposure. Allergic reactions to hexamethylenetetramine, dimethylaminopropylamine and ethylenediamine dihydrochloride were not related to epoxy products.

CONCLUSIONS

Tris-DMP is an important sensitizer in epoxy hardeners, and should be included in the patch test series of epoxy chemicals.

Occupational dermatitis and allergic respiratory diseases in Finnish metalworking machinists

AIM

To investigate the incidences and trends of occupational skin diseases (OSDs) and allergic respiratory diseases (ARDs) in machinists working in the fabrication of metal products.

METHODS

Data from the Finnish Register of Occupational Diseases during 1992-2001 were analysed. Incidence rates for skin and respiratory diseases of machinists were calculated and compared to the total working population. The patients investigated at the Finnish Institute of Occupational Health in the same period were described in detail.

RESULTS

A total of 279 dermatoses and 34 ARDs were reported. Skin diseases accounted for 27% of all occupational diseases. The incidences of the skin and respiratory diseases were 1.6 and 0.2 cases per 1000 person-years, respectively. This represents a 3-fold risk for getting an OSD compared to the total working population. The number of allergic contact dermatitis (ACD) increased 3-fold during the study period. The most common causes of ACD were metalworking fluids (MWFs) and their ingredients such as formaldehyde, ethanolamines and colophony. Eighty-five per cent of ARDs were asthmas. The commonest causes of asthma were metal dusts and fumes, epoxy resins and hardeners and MWFs and their components.

CONCLUSIONS

Contact dermatitis is a common occupational health problem in metalworking machinists, whereas occupational respiratory disease is rare. Only a few specific chemicals in the metalworking have thus far been identified as respiratory allergens. Specific skin tests and inhalation challenge tests with MWFs and their ingredients are recommended if an OSD or a respiratory disease is suspected.

Anaphylaxis and allergic contact urticaria from occupational airborne exposure to HBTU

We describe a case of anaphylaxis and allergic contact urticaria from occupational airborne exposure to HBTU (o-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate), which is a chemical used widely for solid and solution-phase peptide synthesis. Previously, the use of this chemical has been associated with occupational asthma, allergic contact urticaria and allergic contact dermatitis in individual cases, but not with anaphylaxis. Our diagnoses were based on the clinical symptoms, positive skin prick test (SPT) and positive skin provocation test to HBTU. The positive SPT indicates that the anaphylaxis reaction was IgE-mediated. We recommend that in the handling of HBTU, appropriate safety measures should be compulsory, and if work-related symptoms develop, the possibility of anaphylaxis should be considered in advising on appropriate work tasks.

Adducts between nucleophilic amino acids and hexahydrophthalic anhydride, a structure inducing both types I and IV allergy

Haptens causing type I allergy have been shown to predominantly form lysine adducts in the carrier protein, while many haptens giving rise to type IV allergy preferentially form adducts with cysteine residues. Hexahydrophthalic anhydride derivatives are strong sensitizers capable of inducing allergic rhinitis, asthma and urticaria (type I allergy) and allergic contact dermatitis (type IV allergy). The ability of hexahydrophthalic anhydride (HHPA) to form adducts with nucleophilic amino acids and a model peptide in vitro is presented. Adduct formation was monitored by high-performance liquid chromatography with ultraviolet light/vis detection (LC-UV/vis) and high-performance liquid chromatography with mass spectrometric detection (LC/MS). The characterization was obtained by nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS and MS/MS). It was found that HHPA formed adducts with N(alpha)-acetylated lysine and cysteine and the non-acetylated alpha-amino group of proline and, to some extent, also with other nucleophilic amino acids. The adducts with lysine and proline were chemically stable. Addition of one HHPA to a model carrier peptide with all important nucleophilic amino acid residues showed N-terminal proline to be the major site of reaction. The addition of a second hapten gave a lysine adduct, but a minor cysteine adduct was also found. The cysteine-HHPA adducts were shown to be chemically unstable and participated in further reactions with lysine forming lysine-HHPA adducts. The results will be useful for understanding the formation of HHPA-protein adducts with the capability of being markers of exposure, and also to a deeper understanding of the chemical structures causing types I and IV allergy.

Anaphylaxis due to formaldehyde released from root-canal disinfectant

A 50-year-old woman developed anaphylaxis 8 h after application of a paraformaldehyde-containing root canal disinfectant. Radioallergosorbent test showed that she had a high level of formaldehyde-specific IgE in her serum. Prick tests to formaldehyde and paraformaldehyde showed immediate-type responses to both. We reviewed the literature describing cases with anaphylaxis/angioedma caused by formaldehyde in root canal disinfectants and found that about 1/2 of the reported cases developed symptoms over 2 h after dental treatment. We speculated that the delay in the manifestation of her symptoms was possibly due to gradual formaldehyde release from paraformaldehyde and time lag of penetrating and diffusing of formaldehyde outside the dentin. Patch testing showed that she also had delayed-type allergy to formaldehyde, paraformaldehyde and eugenol. Physicians should pay attention to root canal disinfectants, even if anaphylaxis occurs several hours after dental treatment.

Dose-response and time course of specific IgE and IgG after single and repeated topical skin exposure to dry trimellitic anhydride powder in a Brown Norway rat model

BACKGROUND

Trimellitic anhydride (TMA)-induced occupational asthma is thought to be associated with its ability to acylate proteins and to induce production of TMA-specific immunoglobulin (Ig)E. Though the respiratory tract is considered to be a major exposure route leading to airway sensitization, the potential role of dermal exposure producing asthmatic sensitization is not known. The present study examines the ability of dry TMA powder to sensitize Brown Norway rats when applied, topically, to the skin.

METHODS

A patch of hair was carefully clipped with scissors on the rat's back. Dry TMA powder (0.3, 1.25, 5 and 20 mg) was administered on days 0, 7, 14 and 21, and the area occluded with surgical tape overnight after each application. Residual powder recovered from the occluded skin was analyzed by proton nuclear magnetic resonance and was still predominantly TMA. Circulating anti-TMA IgE and IgG were measured by ELISA.

RESULTS

TMA elicited dose-dependent production of specific IgE and IgG. Specific antibodies were detectable 2 weeks after the first TMA exposure and peaked between 3 and 4 weeks.

CONCLUSION

The data suggest that topical skin exposure to dry TMA powder can induce allergic/immunological sensitization as demonstrated by the production of specific antibodies.

Contact urticaria

Contact urticaria has been reported following skin contact with a multitude of substances ranging from simple chemicals to macromolecules. Its prevalence amongst the general population is unknown, but it may be a relatively common and under-recognized phenomenon. Non-immunological (irritant) causes typically elicit mild localized reactions, which clear within hours. Such agents can be found widely in food, cosmetics and medicaments. The lower diagnostic end-point for nonimmunological contact urticaria has been the subject of debate, which makes interpretation of the literature difficult. Immunological (allergic) contact urticaria is due to immediate-type hypersensitivity, and occurs most commonly in atopic individuals. It is mediated primarily by histamine, and may be associated with systemic, and potentially life-threatening symptoms. Natural rubber latex is one of the most important causes today, and the recent 'epidemic' of latex protein allergy has helped draw attention to this subject. Immunological contact urticaria to animal or vegetable matter may occasionally affect those who handle food, and other occupations such as agricultural and veterinary workers. This may be associated with development of a protein contact dermatitis. The diagnosis of immunological contact urticaria can often be confirmed by simple investigations such as skin prick testing or measurement of specific IgE.

Occupational allergic contact dermatitis from unsaturated polyester resin in a car repair putty

BACKGROUND

Unsaturated polyester (UP) resins are widely used as cements in car repair painting to produce a smooth surface before the final painting. We report two car painters with hand and face dermatitis who were sensitized to a UP resin used for car repair cements.

METHODS

Patch testing with commercial substances and ingredients and extracts from UP resins was used to verify the sensitivity.

RESULTS

Both patients showed an allergic patch test reaction to a UP resin. They also had an allergic patch test reaction to diethyleneglycol maleate (DEGM), an extract of a UP resin.

CONCLUSIONS

Both patients had been patch tested elsewhere with negative results because UP resins had not been used for patch testing. Accordingly, patients with dermatitis who have been exposed to UP resins need to be patch tested with UP resins. The specific chemical causing allergic contact dermatitis in our patients was DEGM.