Adriana Teixeira Rodrigues

Outcomes and safety of drug provocation tests.

Drug provocation tests (DPTs) are considered the gold standard for identifying adverse drug reactions (ADRs). The aim of this study was to analyze DPT results and discuss severe systemic reactions associated with them. This was a retrospective analysis of 500 patients with ADRs who sought treatment and were submitted to DPTs when indicated between 2006 and 2010. We performed DPTs according to the European Network for Drug Allergy recommendations. Single-blind, placebo-controlled DPTs were performed with antibiotics, local anesthetics, and nonsteroidal anti-inflammatory drugs, as well as with other drugs. Patient characteristics, DPT results, and reactions were analyzed. The sample comprised 198 patients (80.8% of whom were female patients) submitted to 243 DPTs. Ages ranged from 9 to 84 years (mean, 39.9 years). The 243 DPTs were performed with local anesthetics (n = 93), antibiotics (n = 19), acetaminophen (n = 44), benzydamine (n = 33), COX-2 inhibitors (n = 26), dipyrone (n = 7), aspirin (n = 4), or other drugs (n = 17). The results of 4 tests (1.6%) were inconclusive, whereas those of 10 (4.1%) revealed positive reactions to antibiotics (2/19), COX-2 inhibitors (2/26), acetaminophen (3/44), and local anesthetics (3/93). Two severe reactions were observed: cephalexin-induced anaphylactic shock and bupivacaine-induced anaphylaxis without shock. Four patients (2.0%) reacted to the placebo before administration of the drug. Drug provocation tests are safe for use in clinical practice but they should be placebo-controlled and should be performed under the supervision of an allergist. To confirm a presumptive diagnosis and to manage allergies appropriately, it is crucial to perform DPTs.

Local IgE in patients with allergic rhinitis

Methods We selected 48 patients with moderate to severe rhinitis (12 of them had intermittent asthma) sensitized to Der p without prior treatment with allergen specific immunotherapy. The protocol was approved by the ethics committee. All participants signed informed consent. Determination of total IgE and specific IgE for Der p1 (D1) and Der p2 (D2) were performed in serum and nasal lavage, using ImmunoCAP method. Non parametric tests were used in the statistical analysis.

37 Features of 51 Patients With Perioperative Anaphylaxis History.

Background To evaluate the prevalence and the etiology of perioperative anaphylaxis (APEO) referred to an outpatient clinic specialized in adverse drug reactions. Methods We evaluated 806 patients throw the questionnaire “European Network for Drug Allergy” (ENDA) in the period from October 2006 to June 2011. Patients with a history of APEO were selected. The diagnostic criteria for anaphylaxis were based on the World Allergy Organization. Etiological investigation was made with skin tests for latex, neuromuscular blockers (NMBs), antibiotics, hypnotics, opioids and local anesthetics. Provocation tests for antibiotics, NSAIDs, local anesthetics and latex were also done. Specific IgE was tested for antibiotics (Penicillin G and V, Ampicillin and amoxicillin) and latex. Results We identified 51 (6%) patients with a history of APEO. Among them, 16 patients (31%) had hypersensitivity reactions with positive cutaneous test, 14 patients (27%) abandoned the investigation and 8 patients (16%) completed the investigation with all tests negative. Currently 12 patients (23%) are being investigated and one of them (2%) performed tests to drugs to use in the next sirgury. The main cause of APEO was latex allergy (22%), followed by NMB hypersensitivity (6%). Three patients had positive tests for 2 different agents. Conclusions Latex allergy is the main cause of APEO in this study. The importance of testing all the possible agents involved was demonstrated by the occurrence of 3 cases with positive test for 2 agents.

38 Drug Induced Anaphylaxis in a University Hospital in Sao Paulo, Brazil.

Background Adverse drug reactions (ADRs) are common in clinical practice, most of them presented only with mucocutaneous symptoms. Drug induced anaphylaxis is rare, but it is responsible for most deaths due to ADRs. The aim of this study was to evaluate drug induced anaphylaxis treated in an Allergy Outpatient Clinic of a University Hospital. Methods Retrospective analysis of medical records from patients who seek assistance because of ADR. We looked for clinical criteria for diagnosing anaphylaxis, as recommended in WAO Guidelines. Criteria were classified in numbers 1 to 3:1) Acute onset of an illness (minutes to several hours) with involvement of the skin-mucosal tissue and respiratory and/or cardiovascular compromise; 2) Two or more of the following that occur rapidly after exposure to a likely allergen: involvement of skin-mucosal tissue, respiratory, cardiovascular and/or gastrointestinal compromise; 3) Reduced blood pressure after exposure to known allergen for that patient. We analyzed patients gender and age, drugs involved in reactions and administration of epinephrin. Results We studied 806 patients with history of ADR, of whom 123 (15.3%) presented clinical criteria of anaphylaxis (mean age 39.0 year old, female 101). The first clinical criteria was found in 60.2% and the second one in 38.2%. Epinephrin was injected in only 42 patients (34.1%). Non-steroidal anti-inflammatory drugs (NSAIDs) were most commonly suspected culprit drugs involved in anaphylactic reactions, with 59 patients (47.9%), followed by 40 patients with perioperative anaphylaxis (32.5%), 6 cases due to local anesthetics (4.9%) and 4 to antibiotics (3.2%). Between perioperative anaphylaxis, latex was involved in 10 reactions and neuromuscular blocking agents in 3. Conclusions We found a high prevalence of anaphylaxis, probably because patients with severe ADRs tend to be followed in university hospitals. Nevertheless, anaphylaxis is underdiagnosed in emergency departments, as we observed less than 35% of patients with drug induced anaphylaxis were treated with epinephrin. NSAIDs are still the most common drugs involved in ADRs in Brazil, including severe reactions, as anaphylaxis. In our country, latex still is an important agent incriminated in perioperative anaphylaxis, but anaphylaxis due to antibiotics are less common than in other countries.