Clinical case of clavulanate allergy in a patient with suppurative hidradenitis

Beta-lactam antibiotics include several major groups of drugs that share structural similarities and mechanisms of action and often are first-line therapies for various bacterial infections. In clinical practice all groups of beta-lactam antibiotics are frequently excluded from treatment in case of adverse reactions associated with their use. However, allergic reactions typically develop via sensitization to specific antigenic determinants, rather than to the beta-lactam ring. Therefore, stepwise and thorough allergological evaluation is necessary to accurately define the spectrum of drug hypersensitivity. This article describes the structural characteristics of beta-lactam antibacterial agents and their cross-reactivity, along with key information on types of reactions associated with clavulanate. A clinical case of clavulanate allergy is presented. The diagnostic approach included a stepwise drug testing performed with ceftriaxone, cefixime, amoxicillin/clavulanate, ampicillin and amoxicillin. Immediate-type allergy to clavulanate was confirmed and no cross-reactivity to other beta-lactam antibiotics was discovered. According to personalized recommendations given to the patient, only beta-lactam antibiotics containing clavulanate were contraindicated, rather than the entire class of beta-lactams.