Thimerosal allergy and clinical relevance in Thailand.

BACKGROUND: Thimerosal or merthiolate is used as an antiseptic and a preservative in topical medicaments, cosmetics, and vaccines. Thimerosal is known to cause delayed type hypersensitivity. However, there is argument about the clinical relevance and risk of using thimerosal-preserved products in thimerosal allergic individuals. OBJECTIVE: Retrospective review of patch test results from the Ramathibodi Hospital patch test clinic to determine the prevalence and relevance of allergic reactions to thimerosal in Thailand. MATERIAL AND METHOD: During a 5-year period, thimerosal was patch tested in all patients tested for possible allergic contact dermatitis. Thimerosal was the second most common allergen causing a positive patch test reaction. RESULTS: Of the 433 patients tested, 46 (10.62%) were positive to thimerosal. However, despite the high prevalence of positive reactions none was clinically relevant to their present dermatitis, none of the patients reported reactions to vaccination or cross-reaction to piroxicam. CONCLUSION: There was a high rate of sensitization to thimerosal in Thai patients, but were of little clinical relevance. The author does not advise thimerosal allergic individuals to avoid vaccination, although the small risk of local dermatitis should be pointed out. The topical use of thimerosal containing antiseptics should be avoided.

The study of human skin irritation of a novel herbal skin care product and ingredients by human single closed patch testing.

BACKGROUND: The Government Pharmaceutical Organization of Thailand (GPO) has developed many products using liposome nanotechnology and Thai herbal extracts. OBJECTIVE: Evaluate the irritation potential of GPO products on human skin using the single application closed patch test under occlusion. The authors also studied the moisturizing efficacy of a commercial curmin extract cream (GPO curmin cream). MATERIAL AND METHOD: Thirty-six female volunteers were tested with 12 test materials developed by GPO including liposome, curmin extract: tetrahydrocurcuminoids (THC), and commercial curmin cream. Two and a half percent sodium dodecyl sulfate (SDS) was used as positive control. Standard Finn chambers on Scanpor tape with webril cotton were used as occlusive patch test devices. Cutaneous irritation responses were graded after patch removal and the incidence of irritation compared to the positive control was used for evaluation. Corneometer was used to measure skin hydration before and after application of curmin cream. RESULTS: All volunteers completed the present study. The skin irritation effects from the test materials were significantly lower (p-value < 0.001, McNemar statistic test) than the positive control. Measurement of skin hydration after twice daily application of GPO curmin cream was significantly higher (p-value < 0.001, paired t-test) than the control skin. CONCLUSION: The test materials and finished products developed by the GPO are not likely to induce skin irritation under normal conditions of use. Furthermore, twice-daily application of the commercial GPO curmin cream can significantly increase skin hydration.

Drug eruptions at five institutes in Bangkok.

The study was performed in five hospitals in Bangkok for a period of one year. All in- and outpatients who developed drug eruption from January to December 2001 were enrolled into the study. Physical examinations and complete history-taking were performed by one of the authors. A skin biopsy was done to confirm the diagnosis in every suspected case. Oral challenge test was performed to obtain a definite diagnosis only in some patients with informed consent. Among 212 patients, the most common causative drugs were antimicrobial agents with cephalosporin group in the highest rank. Maculopapular rash was the most common type of drug eruption followed by urticaria and photosensitivity reaction. It was concluded that antimicrobial agents were the predominant causative agents and maculopapular eruption was the most frequent clinical manifestation. New kinds of antimicrobial agents, anti-inflammatory drugs and lipid lowering agents could cause various patterns of drug eruption.

Sweet's syndrome: a reaction to non-tuberculous mycobacterial infections.

Sweet's syndrome has been reported to be associated with many underlying conditions, such as non-tuberculous mycobacterial infections (NTMI). In the literature, only twelve patents with Sweet's syndrome in association with NTMI have been reported (most of the patients were from Thailand). Here, the authors report six more patients who developed Sweet's syndrome as a reaction to NTMI. Four patients had Mycobacterium chelonae/abscessus group infection; one patient had been infected with Mycobacterium avium complex first and became infected with M. chelonae/abscessus group 17 months later; and, the other one had Mycobacterium fortuitum infection. In each patient, the skin lesions of Sweet's syndrome relapsed many times while they still had NTMI, and these lesions usually responded well to short courses of systemic steroids without any deterioration of NTMI.