Update in drug allergy: novel drugs with novel reaction patterns

A case of late-onset larynx angioedema after ranibizumab intravitreal injection: Ranibizumab-related angioedema

This case report describes an unusual case of late-onset larynx angioedema after ranibizumab intravitreal injection. A 72-year-old female patient presented to our clinic for decreased vision; right eye (RE) fundoscopy and optical coherence tomography (OCT) revealed mild chorioretinal atrophy and choroidal neovascularization with subretinal fluid. A ranibizumab injection was planned in the RE, with standard pretreatment with daily oral administration of betamethasone, cetirizine, and ranitidine because her medical history revealed two adverse drug reactions (ADRs) to contrast media (CM). Despite the premedication, 2 h after injection, the patient referred throat closing sensation and dyspnea that resolved within few hours by betamethasone 4 mg intramuscular injection, without further reoccurrence. In occasion of the second intravitreal injection, video rhinofibrolaryngoscopy revealed subglottic edema that resolved within few hours by betamethasone 4 mg intramuscular injection. This report suggests that, even in cases of intravitreal injection, patients with history of allergy, despite the anti-allergic treatment, should be hospitalized to detect late onset of such a life-threatening complication.

Contrast agents in diagnostic imaging: Present and future

Specific contrast agents have been developed for x ray examinations (mainly CT), sonography and Magnetic Resonance Imaging. Most of them are extracellular agents which create different enhancement on basis of different vascularization or on basis of different interstitial network in tissues, but some can be targeted to a particular cell line (e.g. hepatocyte). Microbubbles can be used as carrier for therapeutic drugs which can be released in specific targets under sonographic guidance, decreasing systemic toxicity and increasing therapeutic effect. Radiologists have to choose a particular contrast agent knowing its physical and chemical properties and the possibility of adverse reactions and balancing them with the clinical benefits of a more accurate diagnosis. As for any drug, contrast agents can cause adverse events, which are more frequent with Iodine based CA, but also with Gd based CA and even with sonographic contrast agents hypersensitivity reaction can occur.

The in vitro diagnosis of drug allergy: status and perspectives

Adverse drug reactions (ADR) can result from immune-mediated (drug allergy) and nonimmune-mediated mechanisms. In both types of reaction, conclusive diagnosis and appropriate management remain major problems in daily clinical practice. This review summarizes the potentials and shortcomings of the currently available in vitro tests in the diagnosis of immediate (mostly IgE mediated) and nonimmediate (mostly T-cell mediated) drug allergy, particularly quantification of specific IgE, flow-assisted analysis of in vitro activated lymphocytes and basophils and the enzyme-linked immunosorbent spot.