PPIs hypersensitivity

The clinical presentation of AIN is somewhat varied. Classically, the presentation of drug-induced AIN is divided into a "methicillin-like" presentation or "non-methicillin-like" presentation. AIN associated with me-thicillin presents as a classic hypersensitivity reaction consisting of the triad of fever, rash and eosinophilia. This presentation is much less common in patients who develop AIN from PPI s, with symptoms resembling the "non-methicillin-like" pattern. Although data are not available in all reported cases, it appears that less then 10% of patients with PPl-induced AIN have the... 

C It is recommended that all patients receiving paclitaxel receive pretreatment to reduce the risk and severity of hypersensitivity reactions. The preferred regimen includes a combination of a corticosteroid (such as dexamethasone), an antihistamine (diphenhydramine or equivalent), and an Hj antagonist (such as cimetidine or ranitidine). Omeprazole and other PPIs will not block Hj-receptor sites and do not provide protection against hypersensitivity reactions. 

Hypersensitivity reactions to PPIs may be mild but the spectrum of possible reactions is wide and some may be severe and life-threatening. 

A recently published multicenter study compared the diagnostic accuracy of skin and oral provocation tests in patients with immediate hypersensitivity to PPIs. For the skin tests, specificity and the positive predictive value were both 100 %. The negative predictive value was 91.9 %. 

---