Excellente tolérance du prick-test dans l’exploration des allergies médicamenteuses en milieu de type hospitalier

Introduction

The diagnosis of drug allergy is based on clinical history and skin tests. Although medical literature reports a risk of allergic reactions during skin tests, our experience, based upon several thousands of patients since 1998, strongly suggests that skin tests with drugs are well tolerated.

Patients and methods

In this prospective study, we analysed the adverse effects observed during skin testing of 183 patients explored for suspected drug-induced immediate hypersensitivity, such as urticaria, angioedema, bronchospasm, and anaphylactic shock, between November 2004 and March 2005. Patients were first tested with prick-tests, and with intradermal tests (IDT) at 1/1000 and 1/100 dilutions of the prick solution only when the prick-tests were negative.

Results

One hundred and seventy-nine prick-tests and 169 IDT were realised with drugs diluted by the hospital's chemist. Nine of the 183 patients (5.0%) were diagnosed as having drug-induced immediate-type hypersensitivity, based on a severe suggestive initial reaction and immediate responses in prick or IDT. No reaction was observed during prick testing. IDT induced a non-severe reaction, with less severe symptoms than the initial accident, in one patient only.

Conclusion

Our results confirm the excellent tolerance of prick-tests. Also, they strongly suggest that it is important to investigate drug hypersensitivity with a well-defined protocol, in a hospital setting, starting with pricks and using low concentrations of drugs in IDT.     

Résultats à court et long terme du remplacement valvulaire mitral par prothèse mécanique à bille et à ailettes (à propos d’une série de 236 patients consécutifs avec un suivi moyen de 11 ans)

Objectives

To study the early and late results of mitral valve replacement (MVR) by Starr-Edwards caged-ball and bileaflet mechanical prosthesis.

Material and methods

We retrospectively analyzed 236 MVR performed in 236 patients: 127 by Starr-Edwards prosthesis (group 1) and 109 by bileaflet prosthesis (group 2).

Results

During the early period (30 days), the mortality rate was higher in group 1 (6.3 % vs 1.8 %; p = 0.0001), while hemorrhagic, thromboembolic and infectious complications were comparable in the two groups. In the late period (> 30 days) and with an average follow-up of 11.5 ± 5.7 years, mortality was higher in group 1 (9.4 % vs 4.6 %; p < 0.0001). The same was true for thromboembolic complications (20.8 % vs 6.4 %; p < 0.0001), hemorrhagic complications (13.4 % vs 7.3 %; p = 0.02), infectious complications (3.1 % vs 0.9 %; p = 0.02) and cardiac complications that were not due to the prosthesis (32.3 % vs 14.7 %; p = 0.02). The hemodynamic profile of the bileaflet prostheses was better than that of the Starr-Edwards prostheses (average functional prosthetic surface area was 2.37 ± 0.44 cm² and average pressure gradient was 5.6 ± 1.1 mmHg vs 2.04 ± 0.52 cm² and 7.6 ± 4.9 mmHg).

Conclusion

Our work confirms the superiority of bileaflet mechanical prostheses, with rates of early and late mortality, thromboembolic and hemorrhagic complications lower than those of the Starr-Edwards prostheses in more than 11 years of follow-up. However, one should not forget that the prevention of infective endocarditis, good observance of oral anticoagulant treatment and early surgery before left ventricular dysfunction occurs remain the best guarantee a good result of the MVR.