The diagnosis of hypersensitivity to antibiotics is rarely confirmed by allergy work‐up in cystic fibrosis patients

Abstract

Cystic fibrosis (CF) patients receive many antibiotic treatments for recurrent respiratory infections and frequently report antibiotic hypersensitivity reactions (HSRs).In this retrospective study, medical records of CF patients were reviewed to clarify the clinical features, the culprit antibiotics, and the prevalence of antibiotic HSRs in the CF population. From 601 CF patients, 95 suspected antibiotic HSRs occurred in 60 patients (prevalence of 10.0%). β-Lactams were the most common inducers, but cotrimoxazole was also frequently involved. Seventy-six of 95 suspected HSRs were assessed by allergy workup including skin tests (43/76 reactions) and/or drug reintroduction as a full course of the culprit antibiotic (73 of 76 reactions). From the 43 suspected HSRs that were skin-tested, only three had positive skin tests and were not subjected to drug readministration. All the other 73 suspected HSRs received a full course of the culprit antibiotic: HSR symptoms recurred in 10 of 73 cases and therefore were considered as confirmed antibiotic HSRs; for the remaining 63 suspected HSRs that did not relapse after drug readministration, the diagnosis of antibiotic HSRs was excluded. In summary, 13 of 76 suspected HSRs were confirmed as antibiotic HSRs. The prevalence of suspected and confirmed antibiotic HSRs in CF patients appears similar to that reported in the general population. Of note, most of the antibiotic suspected HSRs are not confirmed after allergology workup. A complete allergy workup appears therefore crucial to make a correct diagnosis and to avoid unnecessary contraindication of major antibiotics. K E Y W O R D Sallergy workup, antibiotic, cystic fibrosis, hypersensitivity

Characterising the allergic profile of children with cystic fibrosis

“…21 Furthermore, chronic infection and prolonged antibiotic exposure have been linked with allergy through T h 2 skewing, and both were prolific in the cohort. 22 Antibiotic use has also been identified as a factor for drug allergy, [33][34][35] and it is probable that the widespread use in this cohort contributed to the frequency of drug reactions seen here.…”

Advances and novel developments in drug hypersensitivity diagnosis

“…20 The time interval between the reaction and the study 21 and the latency for reading the STs 22 can also affect the likelihood for obtaining positive results in ST. 21 This leads to a high heterogeneity in current practice. 5,18 Moreover, differences in the sensitivity of the tests and the diagnostic approach exist due to different regional consumption patterns and to the introduction of new drugs. 3,18 This is the reason why testing subjects with DHRs to beta-lactam antibiotics F I G U R E 1 General diagnostic approach for drug hypersensitivity reactions (BL) may include not only penicillin and its minor determinants, but also amoxicillin, and any suspected BL, to detect side chain-specific sensitizations.…”

“…The time interval between the reaction and the study 21 and the latency for reading the STs 22 can also affect the likelihood for obtaining positive results in ST 21 . This leads to a high heterogeneity in current practice 5,18 . Moreover, differences in the sensitivity of the tests and the diagnostic approach exist due to different regional consumption patterns and to the introduction of new drugs 3,18 .…”

“…It is mainly based on skin testing (ST) and drug provocation tests (DPTs), not risk‐free procedures with still a long way until having a standardized in vitro test available for all laboratories. However, a complete allergy assessment is crucial for allergy delabeling, especially in cystic fibrosis patients with antibiotic hypersensitivity reactions 5 . All this highlights the need for improving the different approaches for diagnosing patients with suspected DHRs 1,6 .…”

“…However, a complete allergy assessment is crucial for allergy delabeling, especially in cystic fibrosis patients with antibiotic hypersensitivity reactions. 5 All this highlights the need for improving the different approaches for diagnosing patients with suspected DHRs. 1,6 In this review, we have analyzed the advances performed in DHRs diagnosis during the last 2 years.…”