Clinical management of adult patients with a history of nonsteroidal anti-inflammatory drug-induced urticaria/angioedema: update

Patient characterization and predictors of aspirin desensitization response

Background

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) may limit the use of aspirin in patients with cardiovascular diseases. Aspirin desensitization, which is a resource-intensive process, can offer such patients access to aspirin through the induction of temporary tolerance to aspirin. However, there is limited information on aspirin desensitization response in patients undergoing aspirin desensitization for cardiac indications in Asia.

Objective

To characterize patients who have undergone aspirin desensitization, evaluate their responses to the procedure, and identify risk factor(s) associated with failure of aspirin desensitization.

Methods

We conducted a retrospective review of medical records of patients who underwent aspirin desensitization in Singapore General Hospital between 1 June 2014 and 31 October 2017. Chi-square or Fisher exact test were used to analyze categorical data while independent samples t test or Wilcoxon rank-sum test were used for continuous data where appropriate. Multivariate logistic regression was used to identify predictors of aspirin desensitization failure.

Results

All 214 patients in our study had cardiovascular indications for aspirin, with angioedema being the most common type of index reaction experienced with NSAIDs (n = 104, 48.6%). One hundred sixty-five patients (77.1%) achieved successful aspirin desensitization. In the selected sample analysis of patients with true NSAID hypersensitivity (n = 163), an index reaction of angioedema to NSAIDs was found to be significantly associated with a higher risk of failing aspirin desensitization (odds ratio, 7.21; 95% confidence interval, 1.94–26.71).

Conclusion

Majority of the patients who underwent aspirin desensitization in our institution were able to achieve tolerance to aspirin. An index reaction of angioedema to NSAIDs was identified as a risk factor for aspirin desensitization failure. This information can aid in the risk stratification of patients undergoing aspirin desensitization and ensure efficient resource allocation for this procedure.

Ibuprofen-induced Anaphylactic Shock in Adult Saudi Patient

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most prescribed medications globally. They act through inhibiting cyclooxygenase (COX)-1 and COX-2 enzymes. In contrast to other NSAIDs, anaphylaxis due to ibuprofen is quite rare, especially in adults. The management of anaphylaxis depends on early recognition of the symptoms, administering epinephrine, and avoidance of the causing allergen. Here, we report a case of a 23-year-old female who presented with anaphylactic shock after ingesting ibuprofen.

Characterization of Patients with Ibuprofen Hypersensitivity

BACKGROUND

Ibuprofen is the most frequently used over-the-counter nonsteroidal anti-inflammatory drug (NSAID) in North America. While it has been commonly implicated in drug-induced hypersensitivity reactions, there is limited literature specifically on ibuprofen hypersensitivity.

OBJECTIVES

To characterize the demographics and clinical course of hypersensitivity reactions in a cohort of patients with ibuprofen allergy.

METHODS

A retrospective chart review of patients diagnosed with ibuprofen allergy was conducted between 2008 and 2016 in an allergy clinic at a tertiary care academic institution. Demographics and clinical information were obtained, and severity of reactions was assessed by a standardized grading system.

RESULTS

A total of 41 patients were included of whom 27 were female. The mean age at first reaction to ibuprofen was 33 ± 13.9 years. The medi an time from the first reaction to the time of diagnosis was 1 year (0-3). The median time from ibuprofen exposure to the onset of symptoms was 30 min (16-101). The median duration of symptoms was 180 min (60-1,440). Urticaria and angioedema were seen in 90% of patients. The reactions were either mild (46%) or moderate (51%) in severity, but 1 patient had severe anaphylaxis. Cross-reactivity to other NSAIDs or acetaminophen was seen and presented with mostly mild reactions.

CONCLUSION

In our cohort of patients, ibuprofen hypersensitivity affected females more commonly than males, and presented with mainly cutaneous manifestations. Onset of symptoms was rapid (< 60 min). Reactions typically ranged in severity from mild to moderate although there was a risk of severe anaphylaxis. There was potential cross-reactivity with other NSAIDs or acetaminophen. The results of our study contribute to the understanding of the demographics and clinical course of ibuprofen hypersensitivity reactions.

Multiple Drug Intolerance Syndrome: An Underreported Distinct Clinical Entity

Aim:

Multiple drug intolerance syndrome (MDIS) is a unique clinical entity distinct from other drug hypersensitivity syndromes. The aim of this review was to critically appraise the various aspects of MDIS.

Methods

A review was conducted to search for the causes, mechanism, clinical features, and management of MDIS.

Results

The most common cause of MDIS is antibiotics followed by non-steroidal anti-inflammatory drugs (NSAIDs). Although some non-specific immunological mechanisms are involved, the immunological tests for MDIS are negative. Rashes, gastrointestinal reflux, headache, cough, muscle ache, fever, dermatitis, hypertension, and psychiatric symptoms are the usual manifestations. Treatment is mostly symptomatic with the withdrawal of the offending drug. Drug re-challenges and desensitization may be required for the management of this syndrome.

Conclusion

MDIS occurs by a nonimmune mechanism which requires a prompt withdrawal of the offending drug(s), and in some cases may require drug re-challenge and desensitization.

Quantification of human C1 esterase inhibitor protein using an automated turbidimetric immunoassay

Background

Impaired levels or function of C1 inhibitor (C1‐INH) results in angioedema due to increased bradykinin. It is important to distinguish between angioedema related to C1‐INH deficiency and that caused by other mechanisms, as treatment options are different. In hereditary (HAE) and acquired (AAE) angioedema, C1‐INH concentration is measured to aid patient diagnosis. Here, we describe an automated turbidimetric assay to measure C1‐INH concentration on the Optilite^® analyzer.

Methods

Linearity, precision, and interference were established over a range of C1‐INH concentrations. The 95th percentile reference interval was generated from 120 healthy adult donors. To compare the Optilite C1‐INH assay with a predicate assay used in a clinical laboratory, samples sent for C1‐INH investigation were used. The predicate results were provided to allow comparison.

Results

The Optilite C1‐INH assay was linear across the measuring range at the standard sample dilution. Intra and interassay variability was <6%. The 95th percentile adult reference interval for the assay was 0.21‐0.38 g/L. There was a strong correlation between the Optilite concentrations and those generated with the predicate assay (R² = 0.94, P < 0.0001, slope y = 0.83x). All patients with Type I HAE (n = 24) and AAE (n = 3) tested had concentrations below the measuring range in both assays, while all patients with unspecified angioedema (UAE), not diagnosed with HAE or AAE had values within the reference range.

Conclusion

The Optilite assay allows the automated and precise quantification of C1‐INH concentrations in patient samples. It could therefore be used as a tool to aid the investigation of patients with angioedema.

Angioedema in the emergency department: a practical guide to differential diagnosis and management

Background

Angioedema is a common presentation in the emergency department (ED). Airway angioedema can be fatal; therefore, prompt diagnosis and correct treatment are vital.

Objective of the review

Based on the findings of two expert panels attended by international experts in angioedema and emergency medicine, this review aims to provide practical guidance on the diagnosis, differentiation, and management of histamine- and bradykinin-mediated angioedema in the ED.

Review

The most common pathophysiology underlying angioedema is mediated by histamine; however, ED staff must be alert for the less common bradykinin-mediated forms of angioedema. Crucially, bradykinin-mediated angioedema does not respond to the same treatment as histamine-mediated angioedema. Bradykinin-mediated angioedema can result from many causes, including hereditary defects in C1 esterase inhibitor (C1-INH), side effects of angiotensin-converting enzyme inhibitors (ACEis), or acquired deficiency in C1-INH. The increased use of ACEis in recent decades has resulted in more frequent encounters with ACEi-induced angioedema in the ED; however, surveys have shown that many ED staff may not know how to recognize or manage bradykinin-mediated angioedema, and hospitals may not have specific medications or protocols in place.

Conclusion

ED physicians must be aware of the different pathophysiologic pathways that lead to angioedema in order to efficiently and effectively manage these potentially fatal conditions.