Severe immediate hypersensitivity reaction (IHR) to contrast media (CM) is one of the legal problems in the hospital. The overall prevalence of IHR was 0.16%-7.7% with nonionic CM. In order to reduce immediate drug adverse reaction and legal problem, prescreening skin testing has been before administration of antibiotics such as penicillin and cephalosporin. It may be important to avoid cross-reactive agent and to select the alternative safe drug. Clinical value of CM prescreening skin testing is controversy. CM prescreening skin testing might be useful for reducing the IHR. We aimed to evaluate the incidence of IHR to nonionic CM in two-step prescreening skin testing group.
This is a retrospective study. We reviewed CT cases performed between Jan. 2008 and Dec. 2014. All patients were performed skin testing just before their pending nonionic CM-enhanced computed tomogram (CT). Skin testing and CT scan were performed through two-step process. One step; 1st Skin test was performed with a common nonionic CM. If 1st skin test negative, nonionic CM-enhanced computed tomogram (CT) was performed. Second step; If 1st skin test positive, 2nd skin tests were performed with two other nonionic CM and saline (negative control). If 2nd skin test negative, 2nd skin test negative nonionic CM-enhanced CT was performed. If 2ndskin test positive, clinician gave patients premedication before enhanced CT or exchanged alternative radiologic test without CM.
IHR were noted in 21 of total 26638 patients (0.08%). 5 of 26638 patients (0.01%) had severe IHR. Symptoms of IHR were nause/vomiting, erythema/urticaria/pruritis,dyspnea, chest tightness, angioedema, hypotension and syncope.
Nonionic CM prescreening skin testing through two-step process may be useful for reducing IHR and for selecting safe CM.