Patch testing vehicle

Lalor, P.A., Revell, P.A., Gray, A.B. et al. (1991) Sensitivity to titanium. J. Bone and Joint Surg., 73B(1), 25-28 Description of possible titanium sensitivity. Patch test vehicle of unknown composition, larger cobalt-chromium component than titanium component in device. Of interest and important, but not conclusive. 

Sensitization results are based on a human maximization test (103) usiag a petrolatum vehicle. The effect is expressed as the number of paneHsts responding over the total number of paneHsts tested and was 0/25 except for spearmint (0/32). That is, at the dose iadicated, the oils werenot irritating when tested ia a 48-h closed patch test ia humans. 

De Groot, A.C., Patch Testing Test Concentrations and Vehicles for 3700 Chemicals, 2nd ed. New York Elsevier Science Ltd May 1994. 

TEST GROUP (15) A. 0.1 ML Substance ID Closed Patch-48H B. 0.1 ml FCA ID Application of C. 0.1 ml Substance Substance + FCA ID Closed Patch-24H Substance Vehicle Closed Patch-24H Vehicle 0... 

Several children and one adult who had previous injections of vaccines or allergens in an aluminum-based vehicle showed hypersensitivity to aluminum chloride in a patch test (Bohler-Sommeregger and Lindemayr 1986 Veien et al. 1986). Dermal hypersensitivity to aluminum appears to be rare in humans. 

Petrolatum continues to be used quite extensively in dermatological applications, primarily for three purposes (1) as an inert patch testing base, (2) as a vehicle in the dermal application of pharmaceuticals, and (3) as a treatment product itself. 

Gammelgaard, B., Fullerton, A., Avnstorp, C., and Menne, T., In vitro evaluation of water and petrolatum as vehicles in chromate patch testing, Contact Dermatitis, 27, 317, 1992. 

Tosti, A., Vincenzi, C., Trevisi, P, and Guerra, L., Euxyl K400 incidence of sensitization, patch test concentration and vehicle, Contact Dermatitis, 33, 193, 1995. 

Dooms-Goossens A, Degreef H. Sensitization to yellow petrolatum used as a vehicle for patch testing. Contact Dermatitis 1980 6(2) 146-7. 

In allergic contact dermatitis due to topical medicaments (6), any constituent of the formulation can be responsible for the adverse event—the vehicle, preservative, emulsifier, perfume, or the active drug. Hence, patch tests should be carried out with all active and supposedly inactive ingredients of the incriminated topical drug. 

Table 1 lists alphabetically a large number of ingredients of cosmetics and topical drugs that can act as sensitizers some drugs are accidental contactants, for example in the pharmaceutical industry or in health personnel. For each compound, the concentration and vehicle for patch-testing, known or generally held to be adequate, are mentioned. 

Table 1 Patch test concentrations and vehicles for skin testing of ingredienfs of topical drugs and cosmetics ...

Chemical Patch test concentration and vehicle Frequency of sensitization References Comments... 

For glucocorticoid allergy, see (13,81,82) and (SEDA-21, 158). For patch-testing glucocorticoids, a 1% concentration in 70% alcohol can be adequate. However, as alcoholic solutions can only be kept in storage for 1-2 months and can cause irritation, petrolatum is the usual choice of vehicle (SEDA-21, 159). 

De Groot AC. Patch Testing. Test Concentrations and Vehicles for 3700 Allergens. Amsterdam Elsevier, 1994. 

In all reported cases, only the whole formulation of vitamin Ki (in its vehicle) or vitamin Ki alone elicited positive patch tests. When individual additives were tested the results were negative. No previous exposure to vitamin Ki was required for the development of type IV hypersensitivity, and primary sensitization occurred within 1-2 weeks or after a longer time period, as in the patient described here. 

Fisher AA, Pascher F, Kanof NB. Allergic contact dermatitis due to ingredients of vehicles. A vehicle tray for patch testing. Arch Dermatol 1971 104(3) 286-290. 

Darsow U, Vieluf D, Ring J Atopy patch test with different vehicles and allergen concentrations An approach to standardisation. J Allergy Clin Irrrmrmol 1995 95 677-684. 

To find a suitable concentration and vehicle for patch testing with different substances, the reader is referred to the standard dermatology textbooks, e.g., (Fregert and Hjorth 1979 Bandmann and Dohn 1967 Fregert and Band-MANN 1975 Malten et al. 1976 Fisher 1973 Cronin 1980). The technical problems and pitfalls in patch testing are dealt with in these texts. 

The patient s skin condition, vehicles, concentration of test substance, volume of test material, test site, time and the number of readings influence the result. Mistakes are easily made. Textbooks on dermatology and contact dermatitis detail the technique and pitfalls. Hjorth (1977) published a comprehensive review of diagnostic patch testing. 

Fisher et al. (1971) introduced the vehicle tray in patch testing and thereby increased the physician s awareness of the possibility of contact allergy to vehicle ingredients. The vast majority of vehicles has not been studied in a systematic fashion they have not been subjected to predictive testing in animals and only limited epidemiologic data exist from screening of eczema patients (Hjorth and Trolle Lassen 1963 Hannuksela et al. 1976 a Iden and Schroeter 1977). 

A different picture arose when the Mayo Clinic examined over 700 eczema patients over a 2-year period for sensitivity to vehicle ingredients (Iden and Schroeter 1977). Here, sensitivity to ethylenediamine reached 7.9%, paraben mixtures in 3.3%, dichlorophene in 2.4%, propylene glycol in 1.5%, lanolin in 1.1%, polysorbate (Tween 20) in 1 %, and sorbic acid in 1 %. In the Danish survey (Hjorth and Trolle Lassen 1963) comprising routine patch testing in 1,664 ecze-... 

Sensitivity to this vehicle is extremely rare, but has been reported in one patient who had positive reactions to all patches in the standard series, where petrolatum was used as vehicle. Patch tests with pure white and yellow soft paraffin were positive (Grimalt and Romaguera 1978). A chronic dermatitis and hyperpigmentation from petrolatum has also been reported (Maibach 1978). 

If manufacturers made available patch test guidelines (i.e., appropriate concentration and vehicle) for individual chemicals and final formulations, the physician could patch test with greater facility and frequency. Unfortunately, it seems probable that the impetus for making this information routinely available will have to be government regulation. 

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