Intradermal skin test results correlate with atopy

Concordance of Skin Prick Test, Intradermal Testing, Serum IgE Levels and Symptoms in Patients with Allergic Rhinitis

Background: Diagnosis of allergic rhinitis is achieved by a combination of patient history and different screening tools, followed by specific provocation testing. Screening tools usually involve a skin prick test (SPT), specific serum IgE or a combination of both. Objective: The purpose of this study was to evaluate the correlation of SPT, intradermal testing and specific serum IgE testing in certain allergens and to evaluate sensitization rates, symptom patterns and time of symptoms in a cohort of patients with suspected allergic rhinitis. Methods: Data on 4653 patients with suspected allergic rhinitis were included and divided into five groups: spring bloomers (birch, hazel, etc.), summer bloomers (grasses and rye), autumn bloomers (ribwort and mugwort), mites and mold. Correlation of SPT, intradermal testing and specific IgE test results using Cohen’s kappa and logistic regression were carried out to evaluate the probability of symptoms. Results: Comparison of SPT and specific serum IgE led to kappa coefficients between 0.33 and 0.47, corresponding to a minor to moderate concordance. Comparing the symptoms reported by patients with sensitization diagnosed by SPT, a correlation was only found for spring and summer bloomers with an odds ratio of 1.5 and 2.1, respectively. The most prevalent symptom in the study cohort was rhinitis, followed by others such as asthma, sense of smell and atopic dermatitis. Conclusions: SPT seems to be more sensitive than specific IgE for detection of sensitization. Patients’ symptoms as well as the timing of symptoms, especially for perennial allergies, are not always very pronounced.

Tacrolimus Immunosuppression Causes Drug-Induced Hypersensitivity Reactions in Liver-Transplant Patients: A 3-Case Report

BACKGROUND

Drug-induced hypersensitivity reactions attributed to the immunosuppressive agent tacrolimus after an organ transplant are rare in the literature. We present 3 cases of male adult patients grafted with a cadaveric liver who developed delayed hypersensitivity reactions to tacrolimus in the form of the prolonged-release capsules (Advagraf). Furthermore, the appropriate drug concentration solutions used for allergy testing are proposed.

METHODS

All patients received a liver transplant (LT) because of cirrhosis of various etiologies. They were immunosuppressed with tacrolimus once daily. Several months after they had been placed on an immunosuppressive regimen with tacrolimus in the form of prolonged-release capsules (Advagraf), the patients presented with delayed hypersensitivity reactions and torturous pruritic rash that affected the whole body and was unresponsive to treatment with oral ursodeoxycholic acid, cholestyramine, or levocetirizine. Allergy testing that was performed by skin prick testing was negative. Nevertheless, intradermal testing yielded positive results in all 3 patients. Management was by interruption of the culprit agent, which was followed by symptom resolution. The immunosuppressive treatment was continued with alternative drugs.

RESULTS

Appropriate nonirritating drug concentration solutions of the drug used for intradermal testing were highly sensitive and confirmed the clinical diagnosis of tacrolimus allergy in all the affected patients.

CONCLUSION

Immunosuppressive treatment with tacrolimus in the form of prolonged-release capsules may cause a drug hypersensitivity reaction. A suspicion of allergy warrants a referral for allergy testing. Pruritic rash refractory to treatment in liver transplanted patients should be evaluated by an allergist for possible drug allergy when bile stasis and graft disease have been excluded. Intradermal testing has proven a highly sensitive method for confirming a drug allergy diagnosis, whereas skin prick testing did not.