Chlorhexidine-related anaphylaxis in urological practice

Introduction: There have been numerous case reports highlighting the risk of anaphylactic reactions when using chlorhexidine-containing urethral gels. However, there is no evidence that the inclusion of chlorhexidine in urethral gels reduces the risk of catheter associated urinary tract infection. Methods: Pubmed and Medline were searched for the keywords anaphylaxis (and) chlorhexidine. Case reports were reviewed and information regarding year, patient demographics, country, chlorhexidine administration route, signs, symptoms encountered and the presence of subsequent allergy testing were analysed. Results: In terms of clinical features, 89% (32/36) of patients were noted to have skin changes recorded as either urticaria, flushing, rash, erythema or wheals. Respiratory changes were recorded in 67% (24/36), which included those described as bronchospasm, chest tightness, wheeze or cough. Hypotension was documented in 92% of reports (33/36) while hypoxia was recorded in half of the reports (18/36) and a quarter (8/36) had periorbital angioedema or documented oral or tongue swelling. Only four out of 36 patients required formal cardiopulmonary resuscitation and no patients died. Conclusion: Chlorhexidine-related anaphylaxis is a relatively frequently reported entity. Despite this, there appears to be no compelling evidence that chlorhexidine mitigates the risk of catheter-associated urinary tract infection. Level of evidence: Level 4 evidence.