ABSTRACT
BACKGROUND: Late patch-test reactions, developing at day (D) 7 or later have been described for several allergens. Late reactions may reflect patch-test sensitization. Para-phenylenediamine (PPD) and epoxy resins (ER) are potent allergens and therefore may potentially induce patch-test sensitization. Up to now, there has been no prospective study on the frequency of late reactions in routine patch testing with these allergens. OBJECTIVES: To assess the frequency of late reactions to PPD and ER. PATIENTS/METHODS: In 1748 patients PPD (PPD-base, 1% pet.) and ER [based on diglycidylether of bisphenol A (DGEBA, 1% pet.)], and in 812 patients, nickel sulphate (5% pet.) were removed from the test panel of the standard series and applied on the medial side of the upper arm. Patch-test occlusion time was 24 h in 588 (PPD and ER) and 241 patients (nickel sulphate), respectively, and 48 h in 1160 (PPD and ER) and 571 (nickel sulphate) patients, respectively. Patch tests were read on D1-3 and D2-3, respectively; additional late readings were performed on D7, D14 and D21 after patch-test application. Patients who were not able to return for all scheduled late readings were telephoned on D7, D14 or D21, and questioned about a reaction at the test sites. Patients were instructed to perform daily self-examination from D4 onwards and to return immediately to the clinic if a reaction at the upper arm became visible. RESULTS: Data of 1428 patients (ER and PPD) and 638 patients (nickel) were evaluable. In 25 patients (1.8%), patch tests became positive not before D7, among them 21 reactions to PPD (1.5%) and four reactions to ER (0.3%). In five of seven patients, repeated patch tests with PPD disclosed patch-test sensitization as the cause of the late reaction. All late reactions, except for one, occurred in patients in whom patch tests were applied for 48 h. No late reactions were seen with nickel sulphate. CONCLUSIONS: PPD (1% pet.) elicited late reactions in 1.5% of routine patch tests, the majority of them probably being caused by patch-test sensitization. Therefore, the German Contact Dermatitis Research Group decided to remove PPD 1% pet. from the German standard series and to take efforts to optimize the patch-test conditions of PPD. One way to optimize PPD testing could be to reduce the exposure of PPD 1% to 24 h. Alternatively the patch-test concentration of PPD might be reduced.
Subject(s)
Allergens/adverse effects , Dermatitis, Allergic Contact/etiology , Epoxy Resins/adverse effects , Patch Tests/adverse effects , Phenylenediamines/adverse effects , Adolescent , Adult , Allergens/administration & dosage , Dermatitis, Allergic Contact/diagnosis , Dermatitis, Occupational/diagnosis , Drug Administration Schedule , Drug Eruptions/etiology , Female , Humans , Male , Middle Aged , Patch Tests/methods , Phenylenediamines/administration & dosage , Prospective Studies , Time FactorsABSTRACT
48 patients suffering from severe acute zoster pain were treated with methylprednisolone 1 mg/kg body weight daily, if bed rest and analgetics had not been effective. The pain completely vanished in 33.3% of the patients; only 20.9% still suffered from unaltered pain. This therapy proved only to be effective if it was applied during the first 5 to 10 days after the appearance of the first lesions. There was no exacerbation observed in any patient. 66.6% of the patients developed postherpetic neuralgia accompanied by rather low pains, as 61.8% of the patients did not need analgetics.
