What can we learn in drug allergy management from World Health Organization's international classifications?

Abstract

Drug hypersensitivity reactions (DHRs) represent growing health problem worldwide, affecting more than 7% of the general population, and represent an important public health problem. However, knowledge in DHRs morbidity and mortality epidemiological data is still not optimal and international comparable standards remain poorly accessed.Institutional databases worldwide increasingly use the WHO International Classification of Diseases (ICD) system to classify diagnoses, health services utilization, and death data. The misclassification of disorders in the ICD system contributes to a lack of ascertainment and recognition of their importance for healthcare planning and resource allocation. It also hampers clinical practice and prevention actions. To further inform the allergy community and to ensure that the revision process is transparent as advised in the WHO ICD-11 revision agenda, we report the advances and use of the pioneering "Drug hypersensitivity" subsection of ICD-11 and implementation in the WHO International Classification of Health Interventions (ICHI). The new classification addressed to DHRs will enable the collection of more accurate epidemiological data to support quality management of patients with drug allergies and better facilitate healthcare planning and decision-making and public health measures to prevent and reduce the morbidity and mortality attributable to DHRs.

Recent developments and highlights in drug hypersensitivity

“…164 Collaborative efforts from policymakers, hospital authorities, healthcare practitioners and patients are crucial to prevent further errors. 165,166 The first step in the management of DHRs must be trying to find safe and effective alternative medications, discarding cross-reactive drugs. 167 Regarding anticonvulsants, cross-reactivity is higher among aromatic drugs 13 than between nonaromatic and aromatic anticonvulsants.…”

Future research trends in understanding the mechanisms underlying allergic diseases for improved patient care

“…DHRs constitute an important health problem, affecting more than 7% of the population, for whom drugs, such as beta‐lactam antibiotics and nonsteroidal anti‐inflammatory drugs, are essential for treatment of common diseases . Based on the clinical characteristics of DHRs, different phenotypes have been identified, although the lack in understanding the underlying mechanisms of many DHRs has hampered the definition of endotypes and identification of biomarkers …”

“…138,139 Based on the clinical characteristics of DHRs, different phenotypes have been identified, 137 although the lack in understanding the underlying mechanisms of many DHRs has hampered the definition of endotypes and identification of biomarkers. 140,141 The classification of DHRs based on the time elapsed between drug administration and development of symptoms is still a matter of debate, because it is difficult to establish a cutoff point to distinguish between immediate and nonimmediate DHRs. 13,136,141 These data are relevant for defining phenotypes and establishing an accurate diagnosis and specific treatment.…”

“…An important recent advance has been the inclusion of "Drug hypersensitivity" as a subsection in the International Classification of Diseases (ICD)-11. 140 The diagnosis of DHR is mainly based on skin tests and drug provocation tests, methods that are not free of risk, still lack standardization, and differ depending on the drug, mechanisms, and even the health system. [142][143][144] There is an urgent need for developing new in vitro diagnostic tests or improving those already existing, 138 such as basophil activation test, 145,146 to improve the diagnostic workup.…”

Food and drug allergy, and anaphylaxis in EAACI journals (2018)

“…The ICD-10 has been revised, and the amendments (ICD-11) in the new "Drug hypersensitivity" subsection have been recently highlighted. 68 An EAACI/ENDA Position Paper was developed for the diagnosis and management of hypersensitivity reactions to non-steroidal antiinflammatory drugs in children and adolescents. 69 Allergies to penicillin, a β-lactam antibiotic, are common, and patients experience symptoms including hives, rash, and itching.…”