Investigação de hipersensibilidade alérgica e não alérgica a medicamentos: proposta de modelo de implantação de serviço

Abstract

Hypersensitivity reactions represent 15% of the universe of adverse drug reactions, among which the most implicated are antibiotics and non-steroidal antiinflammatory drugs (NSAIDs). The objective of the present study was to establish a model an allergic drug testing service (STA) for implantation in public hospitals. It is a descriptive and prospective study. The service was initially implemented at the Dermatology Outpatient Clinic of the Walter Cantídio University Hospital (HUWC) / Federal University of Ceará (UFC). One of the main features of STAM is of a multidisciplinary nature. At the outpatient clinic of the HUWC, active search was performed for patients with pharmacodermia or spontaneous notification by the dermatologist. Upon suspicion, they were referred for evaluation by a volunteer project allergist. By the end of the work, 77 tests were performed, being 41 puncture tests, 12 intradermal tests and 24 epicutaneous tests. An epicutaneous test resulted in oxacillin positivity. Provocation testing could not be performed on patients who tested negative due to the lack of an allergist in the hospital staff and the lack of an emergency room available to the STA. The STA was also implemented in the Immunoallergology service of Albert Sabin Children's Hospital (HIAS), where a very productive partnership began. So far, 3 beta-lactam skin test) by conducting in groups of 10 patients during a halfday period three times a year have been performed. Twenty-four patients underwent penicillin (10,000 IU/Ml), ceftriaxone (2 mg/mL) and ampicillin (20 mg/mL) test, and one child had a positive ceftriaxone intradermal test and a negative test for penicillin and ampicillin. Six oral challenge tests were performed, none of which resulted in positivity. A nucleus of study was also started to evaluate genetic polymorphism in non-allergic hypersensitivity to NSAIDs. Fifty-five patients with multiple hypersensitivity to NSAIDs (previously diagnosed in STA) and 95 controls without hypersensitivity were selected and a genetic library was created with DNA samples extracted from peripheral blood samples collected from patients and controls. In the present work, fragment length polymorphism techniques were established for analysis of IL-10 (592 C> A) and leukotriene synthase (-444A> C). The IL-10 results (592 C> A) are partial and show that the C allele, corresponding to a larger amount of interleukin 10, was quite frequent in the cases. As for leukotriene synthase (-444A> C), it is believed that there was some technical problem because all samples, both case and controls, presented 100% heterozygous genotype. The STA has provided an important integra- tion between the health professionals involved and effectively represents a service of great benefit to the patient, since there is a goal of diagnosing drug allergy. In addition, the creation of the genetic polymorphism nucleus of study in non-allergic hypersensitivity to NSAIDs represents a great advance for the knowledge of the mechanisms present in this type of hypersensitivity.