Are drug provocation tests still necessary to test the safety of COX-2 inhibitors in patients with cross-reactive NSAID hypersensitivity?

Hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAIDs) - a retrospective study

BACKGROUND

The aim of this study was to verify the validity of clinical history and oral provocation challenges of patients with NSAID hypersensitivity and to identify safe alternatives. The COX-2 inhibitor etoricoxib, in particular, was studied.

PATIENTS AND METHODS

In all, 104 patients with confirmed diagnoses of NSAID hypersensitivity treated at the Department of Dermatology, Frankfurt University Hospital, Germany between 2004 and 2012 were retrospectively studied.

RESULTS

The medical history and hypersensitivity symptoms during oral provocation testing (OPT) largely coincided and were mostly mild to moderate. Acetylsalicylic acid (ASA) was the most frequent trigger both anamnestically (27.9 %) and during OPT (47.8 %). Etoricoxib caused the fewest reactions during OPT (4.2 %). Acetaminophen led to reactions in only 6.7 % of the cases studied although it was named more often in clinical histories (14 %).

CONCLUSIONS

OPT should be the aim whenever possible as most symptoms are mild to moderate. To distinguish between selective and cross-hypersensitivity reactions, ASA should be part of the test protocol. Furthermore, the findings of this study indicate that etoricoxib and acetaminophen are safe treatment alternatives in case of NSAID hypersensitivity. However, these drugs should not be administered without prior OPT in an inpatient setting, as severe symptoms can occur.

Pro and Contra: Provocation Tests in Drug Hypersensitivity

Drug provocation test (DPT) is the controlled administration of a drug to diagnose immune- or non-immune-mediated drug hypersensitivity and the last step for accurate recognition of drug hypersensitivity reactions when the previous diagnostic evaluations are negative or unavailable. A DPT is performed only if other conventional tests fail to yield conclusive results. In each clinical presentation, "to provoke or not to provoke" a patient should be decided after careful assessment of the risk-benefit ratio. Well-defined benefits of DPT include confirmative exclusion of diagnoses of drug hypersensitivity and provision of safe alternatives. However, disadvantages such as safety, difficulty in interpretations of results, lack of objective biomarkers, risks of resensitization, efficiency in daily practice, and lack of standardized protocols, are poorly debated. This review summarizes the current published research concerning DPT, with particular emphasis on the advantages and disadvantages of DPT in an evidence-based manner.

Drug allergy in tertiary care in Turkey: results of a national survey. The ADAPT study: adult drug allergy perception in Turkey

BACKGROUND

No data are available on the incidence of drug hypersensitivity (DH) reactions in outpatient settings of tertiary allergy/immunology clinics. Our aims were to document the frequency of outpatient hospital admissions due to DH reactions to allergy/immunology clinics in adults and the management of these reactions in real life. We also investigated whether drug allergy affected social and medical behaviours of the patients.

METHODS

This multi-centre study was performed for one year with the participation of 11 out of 16 tertiary allergy/clinical immunology clinics in Turkey. The study group consisted of the patients with DH reactions. Results of a questionnaire including drug reactions and management were recorded.

RESULTS

Among 54,863 patients, 1000 patients with DH were enrolled with a median of 2.1% of all admissions. In real life conditions, the majority of approaches were performed for finding safe alternatives (65.5%; 1102 out of 1683) with 11.7% positivity. Diagnostic procedures were positive in 27% (154/581) of the patients. The majority of the patients had higher VAS scores for anxiety. A total of 250 subjects (25%) reported that they delayed some medical procedures because of DH.

CONCLUSION

Our results documented the frequency of admissions due to DH reactions to allergy/clinical immunology clinics for the first time. Although physicians mostly preferred to perform drug tests in order to find safe alternatives, considering the fact that DH was confirmed in 27% of the patients, use of diagnostic tests should be encouraged, if no contraindication exists in order to avoid mislabelling patients as DH.

Challenge-proven nonsteroidal anti-inflammatory drug hypersensitivity in children

BACKGROUND

Few studies investigated hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) in children. The objective was to determine the frequency of true NSAID hypersensitivity (NSAID-H) and whether there were any parameters in the history of children that would predict NSAID-H. Secondly, an investigation was conducted into whether NSAID-hypersensitive children could tolerate safe alternatives. Differing from previous studies, the researchers followed the recent diagnostic algorithm proposed for acute reactions in NSAID-H.

METHODS

Children with a history suggesting NSAID-H were evaluated by an allergist. The patients with a single NSAID in history were tested first with a skin prick test and if negative challenged with the culprit NSAID. The patients who had reactions with multiple NSAIDs were directly challenged with their culprit drugs. Safe alternatives in children with a confirmed NSAID-H were found by oral provocation tests (OPTs).

RESULTS

Fifty-eight of 61 patients participated in the study. Thirty-eight patients (65.5%) described a reaction to a single NSAID and 20 mentioned reactions with ≥2 different NSAIDs. Single-drug-induced and cross-reactive NSAID-Hs were proven in 5 of 36 (14%) and 8 of 18 (44%) of patients, respectively. Acetaminophen and nimesulide were tolerated in 60% and 88.8% of the study patients as safe alternatives, respectively. Family history of NSAID-H was found as the only significant predictor of OPT (OR: 5.4; 95% CI: 1.02-28.6).

CONCLUSION

Histories of both single and multiple NSAID-Hs are poor predictors of actual drug hypersensitivity. Therefore, diagnostic tests should be performed in all children if no contraindication exits. Family history of NSAID-H is the only significant parameter predicting OPT results.