Topical provocation of fixed drug eruption

Abstract

To determine whether topical provocation could be used for the diagnosis of fixed drug eruption (FDE) instead of systemic provocation, we applied the suspected drug at various concentrations (1-10%) in either petrolatum, 94% ethanol or dimethyl sulphoxide (DMSO) as an open test on both clinically normal skin and on previous FDE lesions in 24 patients with established FDE due to phenazone salicylate, a sulphonamide, doxycycline, trimethoprim, chlormezanone, a barbiturate, or carbamazepine. In 18 of the 24 patients, local provocation of FDE was seen at sites or previous eruption but never on clinically normal skin. With some drugs, e.g. phenazone salicylate, positive provocation of FDE was seen with all the vehicles used; with sulphamethoxazole and trimethoprim, a positive result was seen only in DMSO. To study cross-reactions to other phenazone derivatives in patients with an FDE caused by phenazone salicylate, we applied topical phenazone, aminophenazone and propyphenazone to sites of previous FDE lesions in three patients. In all three, a positive reaction was seen with phenazone, but only one patient showed positive results with aminophenazone and propyphenazone. The present study suggests that topical provocation is useful with several drugs causing FDE. Testing should always be performed on sites of previous FDE, and the sensitivity of the open topical testing can be increased in certain cases by using a vehicle which increases penetration of the drug.

Guidelines for performing skin tests withdrugs in the investigation of cutaneous adverse drug reactions

“…From our results (1, 2, 5, 6) and those obtained from the literature, we consider that patch tests are of value in determining the responsible drug in generalized eczema, systemic contact dermatitis, baboon syndrome, maculopapular rash (1,2,5,6,24), AGEP (25), lichenoid rash and fixed drug eruption (11), and that photopatch tests may be useful in studying drug photosensitivity (10,26). On the other hand, they are of less value in investigating urticaria (1), Stevens-Johnson or Lyell's syndrome (25), pruritus or vasculitis (2).…”

“…In patients with a high imputability of one drug in the onset of their CADR, drug patch tests had positive results in 43% of 72 patients (1), 50% of 108 patients (2), 43.9% of 66 patients (5), and 31.7% of 197 patients (3). Positive relevant results depend on the clinico-evolutive type of CADR, on the respon-sible drug, on the drug concentration and vehicle used (1,2,5), and even on the skin sites where tests are performed (8,11,12,(15)(16)(17).…”

Topical Provocation in Fixed Drug Eruption from Nonsteroidal Anti-Inflammatory Drugs

“…Phenazone salicylate, barbiturates and tetracyclines, the main drugs responsible for FDE a few decades ago [1,4,5], have largely been outnumbered by cotrimoxazole [2,3] and nonsteroidal anti-inflammatory drugs (NSAID), as in our experience [6,7].…”

“…Patch testing, which is well standardized for studying allergic contact dermatitis (ACD), is often useful in the diagnosis of the offending drug in FDE [3][4][5][6][7]. Nevertheless, as there are differences in the clinical and physiopathological aspects of these two entities, this technique has to be adapted to the study of FDE so that we can retrieve the most specific and sensitive results.…”

“…I3 PRX2 F 70 3 oedema 3 yes + I4 PRX3 M 56 4 oedema + vesicles 3 no + I4 PRX4 F 61 5 eventually with extensive lesional skin detachment [1][2][3]. Epicutaneous testing performed on residual lesions of FDE is often positive [3][4][5][6][7], but there are still many aspects of standardization in this procedure that have not been fulfilled, namely in the study of NSAID.…”