DIAGNOSTIC TESTING FOR DRUG HYPERSENSITIVITY

Healthcare Providers' knowledge, attitudes and practice in relation to drug hypersensitivity reactions at King Abdulaziz Medical City in Riyadh

Background

Drug hypersensitivity reactions (DHRs) are immune-mediated responses triggered by exposure to a drug. DHRs are responsible for serious adverse drug reactions (ADRs) and are considered the fifth leading cause of death. This study aims to assess and evaluate the knowledge, practice, and attitudes of healthcare providers (HCPs) towards DHRs.

Methods

A cross-sectional survey was conducted at King Abdulaziz Medical City (KAMC) in Riyadh, Saudi Arabia. Healthcare providers, including pharmacists, physicians, and nurses, were recruited using a convenience sampling method to complete the survey. The survey comprised three domains: knowledge (14 items), attitudes (5 items), and practices (6 items), utilizing a standardized self-administered questionnaire.

Results

The survey was completed by 373 healthcare providers. The respondents were predominantly female (72.1 %) with a mean age of 33.8 ± 7.8 years. Of the respondents, 64 % were nurses, 25 % pharmacists, and 11.3 % physicians. Educational levels varied, with 53 % holding a bachelor's degree, 22 % an associate degree, and 25 % a master's degree or higher. The median knowledge score was 48. Female healthcare providers, those with advanced levels of education, and physicians had higher knowledge scores compared to male and nurse participants (p < 0.05). One-third of the respondents (33 %) were satisfied with their knowledge of DHRs, and 42 % believed HCPs should receive more advanced training in DHR management. Less than a quarter of HCPs reported inquiring about patients' histories of hypersensitivity reactions.

Conclusions

The study revealed that healthcare workers had a relatively low level of knowledge about drug hypersensitivity reactions and lacked a consensus on DHR management. While displaying a positive attitude towards DHRs, they often did not translate this attitude into consistent clinical practice.

Allergic reactions due to concomitant administration of multiple drugs in intravenous fluid in emergency departments in Turkey

The present study aimed to evaluate patients who were referred to adult allergy clinic due to allergic reactions after concomitant multiple intravenous-drug administrations in Emergency Department (ED). Between January 2017 and January 2019, patients admitted to our allergy clinic with hypersensitivity reactions to intravenous drugs administered in ED were included retrospectively. Fifty-seven patients who developed allergic reactions after intravenous drug administration in EDs were evaluated. Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) were the most common cause of allergic reactions (n = 40, 70.2%). Skin Prick Tests (SPT) were positive in 6 (10.5%) patients. Drug Provocation Tests (DPT) were positive in 10 (17.5%) patients. No significant correlation was found between the total number of drugs in the intravenous fluid and the degree of allergic reaction (r = -0.145, p = 0.282). There was no statistically significant difference between the degree of allergic reaction and history of atopic disease (p = 0.579). In conclusion, concomitant administration of multiple drugs in intravenous fluids may increase the risk of allergic reactions.

Adverse Drug Reactions

Adverse events and adverse drug reactions are common in clinical practice. Side effects range from the common to the rare and may be confused with other mucocutaneous manifestations resulting from several medications to treat infections, other medical conditions, and in the clinical setting of oncologic treatment. The objective of this chapter to review current data on adverse drug reactions, here classified as (i) severe adverse drug reactions, (ii) uncomplicated cutaneous adverse drug reactions, and (iii) adverse drug reactions caused by chemotherapy drugs, particularly those cases whereby the dermatologist is requested to issue a report and asked to comment on the safety and viability of readministration of a specific drug. We describe aspects associated with these events, presenting a detailed analysis of each of them.

Provocation tests in drug hypersensitivity

Provocation tests are regarded as the "gold standard" to establish or exclude the presence of hypersensitivity to a certain drugs because they reproduce not only allergy symptoms but other adverse manifestations, irrespective of their pathomechanism. Provocation testing is potentially harmful and should be considered only after balancing the risk-benefit ratio in the individual patient. The reasons for false-positive and false-negative results are numerous, including loss of sensitization, cofactors not being included in the diagnostic procedure, and the potential induction of tolerance during provocation. When conducted by experienced clinicians in a carefully monitored setting, however, drug provocation testing is a safe method to confirm or exclude drug hypersensitivity.

Reações cutâneas desencadeadas por drogas

FUNDAMENTOS: Drogas podem desencadear reações adversas. As manifestações cutâneas são as mais comuns. OBJETIVO: Analisar as farmacodermias e relacionar as drogas envolvidas e os tipos de reações cutâneas mais freqüentes. MÉTODOS: Estudo retrospectivo e descritivo. Avaliados pacientes com diagnóstico inicial de farmacodermia internados na Enfermaria de Dermatologia, no período de janeiro de 1999 a junho de 2004. Incluídos no estudo os pacientes que confirmaram o diagnóstico de farmacodermia, com base em critérios clínicos e histopatológicos, após a análise dos prontuários. RESULTADOS: Tiveram diagnóstico inicial de farmacodermia 121 pacientes. Incluídos 43 pacientes, dos quais 51,2% eram do sexo feminino, e 86% da raça branca. Destes, 48,8% faziam uso de apenas uma medicação, sendo o grupo dos antibióticos o mais utilizado (20,9%) e o principal responsável pela farmacodermia(33,3%). O segundo grupo de drogas mais envolvido foi o dos antiinflamatórios (16,7%), seguido pelo dos anticonvulsivantes (13%), e analgésicos/antipiréticos (13%). A forma clínica da erupção cutânea foi exantema maculopapular em 41,9% dos pacientes, eritrodermia em 25,6% e urticária em 23,3%. CONCLUSÃO: O exantema maculopapular foi a principal forma de reação cutânea desencadeada por drogas, e os antibióticos, os medicamentos que mais freqüentemente desencadearam essas reações.

Approach to patients with suspected hypersensitivity to local anesthetics

Adverse reactions to local anesthetics are relatively common, but true IgE-mediated hypersensitivity is extremely rare. Fortunately, the vast majority of adverse reactions occur via nonimmunologic means, but considerable confusion still exists among providers. We conducted a review of the literature to determine if earlier estimates of IgE-mediated allergy are consistent with current reports and whether current management strategies are consistent with these findings. We identified several confounding variables involved in the evaluation, including the roles of preservatives/additives, epinephrine, latex, and inadequate testing procedures. These problems may cause significant diagnostic challenges for clinicians. It is in fact much more likely that there is an alternate diagnosis, and in many cases clinicians can begin the evaluation in the office. When local anesthetic allergy is still suspected, the patient should be referred to an allergist for testing to determine if the suspected culprit drug can be safely used, or, if necessary, identify a suitable alternative.

Allergy to drugs: is there an association with mental ill-health?

Objectives. Hypersensitivity reactions to drugs are not infrequent. A certain of anxiety, aggression or depression should be expected in patients with drug allergies, as they could experience symptoms ranging from mild to life-threatening reactions following consumption of drug. However, a literature search resulted in very limited data. This study was designed to evaluate the psychological status of patients with drug allergy and to assess the relationships between psychological evaluations of the patients and, duration of drug allergy, type of allergic reaction, hypersensitivity reaction of the type of drug involved. Methods. The study group comprised 61 patients (43 F, 18 M), age ranging from 16 to 75 years, with reliable history of drug allergy. A total of 55 healthy subjects (39F, 16M) age ranging from 17 to 70 years served as control group. Assessment tools consisted of Beck Depression Inventory (BDI), and Speilberger's State-Trait Anxiety Inventory (STAI Tx-2). Results. The prevalence of depression and anxiety among patients with drug allergies was not greater than that of the controls. There were no associations between the scores of these psychological assessments and duration of drug allergy, type of allergic reaction, type of drug. Conclusions. Our data suggest that follow-up studies including high numbers of patients and patients with specific and potentially life-threatening clinical pictures of drug allergies are needed to detect clinically relevant associations.

Reações cutâneas graves adversas a drogas - aspectos relevantes ao diagnóstico e ao tratamento - Parte I - Anafilaxia e reações anafilactóides, eritrodermias e o espectro clínico da síndrome de Stevens-Johnson & necrólise epidérmica tóxica (Doença de Lyell)

As reações cutâneas graves adversas a droga (RCGAD) são as que geralmente necessitam de internação hospitalar, por vezes em unidade de terapia intensiva ou de queimados, com observação minuciosa dos sinais vitais e da função de órgãos internos. O objetivo é descrever essas reações, facilitando seu reconhecimento e tratamento. Fazem parte desse grupo a anafilaxia, a síndrome de Stevens-Johnson (SSJ), a necrólise epidérmica tóxica (NET) e, dependendo do envolvimento sistêmico, as eritrodermias. Neste artigo, são abordados as características clínicas e o tratamento de algumas reações adversas a droga: anafilaxia, as eritrodermias, a síndrome de Stevens-Johnson (SSJ) e a necrólise epidérmica tóxica (NET).

Evaluation of adverse reactions to local anesthetics: experience with 236 patients

BACKGROUND

Adverse reactions to local anesthetics (LAs) are frequently reported. Although most of these reactions are not immune mediated, many patients are referred to allergy clinics and undergo extensive evaluation.

OBJECTIVE

To determine the prevalence of true LA allergy among the patients referred for suspected hypersensitivity and to evaluate the usefulness of the currently used evaluation protocol.

METHODS

A total of 236 patients referred to our allergy clinic for investigation of LA hypersensitivity were included in this study. The evaluation protocol was composed of skin prick and intradermal tests, followed by subcutaneous challenge with unrelated LA preparations that contained preservatives.

RESULTS

Skin prick and intradermal test results were negative for all subjects. No objective adverse reactions were observed during the challenge in all but 1 patient, who developed local erythema at the site of injection and later underwent an uneventful challenge with a different LA.

CONCLUSIONS

Allergic reactions were not reproduced during testing and challenge with LA preparations that contained preservatives or preservatives with adrenaline in our large group of patients with suspected LA allergy. Since both prick and intradermal skin test results were negative in all the patients and did not provide us with useful information, we propose to modify the standard protocol by omitting intradermal tests and shortening the challenge. We also suggest that the whole procedure be performed with LAs that contain preservatives, which are usually the preferred preparations widely used in daily practice.

10. Drug allergy

Adverse drug reactions are common, but only 6% to 10% are immunologically mediated. Unlike most adverse drug reactions, allergic drug reactions are unpredictable. Whereas some drug-induced allergic reactions may be easily classified into one of the four Gell and Coombs hypersensitivity categories, many others that appear to have an immunologic component cannot be classified because of our lack of mechanistic information. Theoretically, any drug can induce an immune response. However, some drugs are more likely to elicit clinically relevant immune responses than are others. Drugs in this category include antimicrobial drugs, anticonvulsants, chemotherapeutic agents, heparin, insulin, protamine, and biologic response modifiers. After a drug-disease connection is established, it must be determined whether the reaction was immunologically mediated. Subsequently, confirmatory tests, if available, should be used to determine the allergic status of the patient. If these tests are not available, a graded challenge or desensitization may be considered, depending on the type of clinical reaction previously demonstrated and the need for drug readministration. Education of the patient and primary care physician is an important component of patient management.

Drug allergy diagnosis in humans: possibilities and pitfalls

Due to the potential hazards of drug allergies, an early and reliable diagnosis is crucial. The use of in vivo tests is not recent but, because of the hazards of skin testing in patients with a history of anaphylaxis, they had been abandoned for a while. Recent reevaluations have shown that for some drugs, e.g. antibiotics-reliable skin tests can ensure the diagnosis of drug allergy in up to 70% of cases. Many in vitro tests based on well-defined mechanisms, e.g. the basophil degranulation test have been used for the diagnosis of totally unrelated allergic mechanisms. It is almost impossible to interpret their validity as diagnosis tools. Nevertheless, other tests, e.g. the lymphocyte transformation test which have been evaluated in well-conducted recent studies, seem to have a good predictive value. Their use is still restricted to clinical trials or research studies. A reliable clinical approach as well as a detailed examination of the drug intake remains obligatory to diagnose drug allergy. Available in vivo and in vitro tests are sometimes used to confirm the diagnosis. The sensitivity and specificity of these tests is evaluated in clinical studies. Research to improve the existing tests and to develop new diagnostic tools is still of paramount importance.

Understanding drug allergies

At this time, the incidence of adverse drug reactions can only be estimated because the intensive monitoring and documenting that is required to make this determination does not exist at most hospitals and clinics. Despite these limitations, a meta-analysis of prospective studies has estimated the incidence of serious adverse drug reactions in hospitalized patients to be 6.7% and the incidence of fatal adverse drug reactions to be 0.32%. When evaluating and managing the condition of a patient who has experienced an adverse drug reaction, the physician first obtains an accurate history and performs a careful physical examination to determine whether the reaction was immunologic in nature. Drug reactions that are immunologically mediated (1) require a period of sensitization, (2) occur in a small proportion of the population, (3) are elicited at drug doses far below the therapeutic range, and (4) subside after drug discontinuation in most instances. All possible culprit drugs should be identified, with dosages and dates of administration and discontinuation, and the patient should be asked about any previous drug exposure history. Although immunodiagnostic tests for allergic drug reactions are limited, several tests do exist and may be useful in the identification of drug-specific antibodies, drug-specific T lymphocytes, or mediators from activated cells. If the reaction was not consistent with an IgE-mediated event and if it did not involve serious organ damage, cautious rechallenge may be considered. For those reactions that appear to be IgE-mediated and for which there is no reliable skin test reagent, drug desensitization may be performed by allergists who are trained in this procedure.