Ketoconazole


Ketoconazole is a synthetic imidazole-derivative antifungal agent used in the treatment of systemic and subcutaneous mycosis; also effective in the treatment of dermatophytosis and superficial mycosis.
 
Incidence
Very low (4 cases published).
 
Clinical manifestations
Anaphylactic shock.
 
Pruritus, rash, urticaria, facial angioedema.
 
Diagnostic methods
Cutaneous testing
 
Skin-prick tests with 1, 10, 20, 40 mg/ ml positive with a concentration of 10 mg/ ml in a patient with allergic reaction to ketoconazole.
 
No specific IgE found.
 
Histamine release test was positive in the same patient.
 
Oral challenge: 25 mg, 50 mg, 100 mg, 200 mg positive in the same patient following a cumulative dose of 75 mg.
 
Mechanisms
IgE-mediated hypersensitivity is likely.
 
Cross-reactivity with other azole derivatives is possible, but not demonstrated.
 
Management
Avoidance.

References

  1. Beal M, Bernard C, Zenut M, Simmonnet F, Lavarenne J, Boch C, "Reaction anaphylactique au ketoconazole", Therapie., 1996 ; 51 (5): 604-5
  2. Gonzalez-Delgado P, Florido-Lopez F, Saenz de San Pedro B, Cuevas-Agusti M, Marin-Pozo J.F,"Hypersensitivity to ketoconazole", Ann. Allergy., 1994 ; 73 (4): 326-8

As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.