Severe allergic reaction to an intraurethral preparation containing chlorhexidine

Allergic and other adverse reactions to drugs used in anesthesia and surgery

The list of drugs patients may be exposed to during the perioperative and postoperative periods is potentially extensive. It includes induction agents, neuromuscular blocking drugs (NMBDs), opioids, antibiotics, sugammadex, colloids, local anesthetics, polypeptides, antifibrinolytic agents, heparin and related anticoagulants, blue dyes, chlorhexidine, and a range of other agents depending on several factors related to individual patients’ clinical condition and progress in the postoperative recovery period. To avoid poor or ultrarapid metabolizers to a particular drug (for example tramadol and codeine) or possible adverse drug reactions (ADRs), some drugs may need to be avoided during or after surgery. This will be the case for patients with a history of anaphylaxis or other adverse events/intolerances to a known drug. Other drugs may be ceased for a period before surgery, e.g., anticoagulants that increase the chance of bleeding; diuretics for patients with acute renal failure; antihypertensives relative to kidney injury after major vascular surgery; and serotonergic drugs that together with some opioids may rarely induce serotonin toxicity. Studies of germline variations shown by genotyping and phenotyping to identify a predisposition of genetic factors to ADRs offer an increasingly important approach to individualize drug therapy. Studies of associations of human leukocyte antigen (HLA) genes with some serious delayed immune-mediated reactions are ongoing and variations of drug-metabolizing cytochrome CYP450 enzymes, P-glycoprotein, and catechol-O -methyltransferase show promise for the assessment of ADRs and non-responses to drugs, particularly opioids and other analgesics. Surveys of ADRs from an increasing number of institutions often cover small numbers of patients, are retrospective in nature, fail to clearly identify culprit drugs, and do not adequately distinguish immune-mediated from non-immune-mediated anaphylactoid reactions. From the many surveys undertaken, the large list of agents identified during and after anesthesia and surgery are examined for their ADR involvement. Drugs are classified into those most often involved, (NMBD and antibiotics); drugs that are becoming more frequently implicated, namely antibiotics (particularly teicoplanin), and blue dyes; those becoming less frequently involved; and drugs more rarely involved in perioperative, and postoperative adverse reactions but still important and necessary to keep in mind for the occasional potential sensitive patient. Clinicians should be aware of the similarities between drug-induced true allergic type I IgE/FcεRI- and pseudoallergic MRGPRX2-mediated ADRs, the clinical features of each, and their distinguishing characteristics. Procedures for identifying MRGPRX2 agonists and diagnosing and distinguishing pseudoallergic from allergic reaction mechanisms are discussed.

Review of allergic reactions from use of chlorhexidine on medical products in clinical settings over 40 years: Risks and mitigations

Chlorhexidine is an antimicrobial agent widely used for infection prevention in medical settings. Nevertheless, allergic reactions ranging from mild to severe have been reported following its use. In this review, we analyzed all case reports published between the introduction of chlorhexidine and the end of 2019 for allergic responses associated with the use of medical devices and or other medical products containing chlorhexidine (CHX) to ascertain the prevalence of severe CHX allergic reactions and what practices might best mitigate those risks.In total, 77 publications containing 124 reported cases of allergic reactions were grouped into 3 product categories, catheters, semisolids, and fluid products. The country, type of reaction, route of sensitization, allergy confirmation, and intervention or mitigation was extracted for each case. Overall, 30 cases were associated with catheters, 46 cases were associated with semisolid products, and 48 cases were associated with the use of other medical products. Severe cases were managed with intravenous fluids, steroids, and epinephrine (adrenaline). None of the reported cases were fatal. The allergy risks can be mitigated by better warning and training clinicians and by recording and screening patient histories for CHX presensitization from prior exposure. For patients undergoing pre-use blood tests, IgE antibody screens can also be performed. Finally, as a precaution in the event a rare severe allergic reaction occurs, procedure carts and rooms can be prestocked with injectable epinephrine and other rapidly acting anti-inflammatory medications.

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.

Allergy to Chlorhexidine

Chlorhexidine is an effective antiseptic which is widely used in dentistry. Over recent years, it has also been used in other healthcare products as well as in cosmetics. Anaphylaxis to chlorhexidine has been increasingly reported throughout the world, including two incidents in the UK where chlorhexidine-containing mouthwash had been used to wash tooth sockets following recent tooth extraction. Chlorhexidine is under-recognized as a cause of anaphylaxis and dentists should be aware of its potential for serious adverse effects. Dentists need to consider whether the washing out of a tooth socket with chlorhexidine solution should be avoided in the treatment of established dry socket. On current evidence the potential risks of using chlorhexidine as irrigation solution for treating an established dry socket appears to outweigh any known benefit. CPD/Clinical Relevance: Chlorhexidine has the potential to cause anaphylaxis in the dental surgery.

Chlorhexidine-induced anaphylaxis in surgical patients: a review of the literature

BACKGROUND

Chlorhexidine (CHL) has antiseptic and disinfectant properties used to prevent hospital-acquired infections. CHL-induced anaphylaxis is poorly reported in surgical literature despite government warnings and growing recognition. The aim of this review is to increase awareness of CHL-induced anaphylaxis in the surgical population.

METHODS

Literature review of Embase, Medline, PubMed and the Cochrane library using 'anaphylaxis (and) chlorhexidine' search terms.

RESULTS

Thirty-six articles were published on surgical patients suffering anaphylaxis to CHL. Within these, seven patients had two proven separate anaphylactic reactions and one had three separate proven anaphylactic reactions. The most commonly affected speciality was urology. The majority occurred during elective procedures. A history of atopy was surprisingly uncommon as was bronchospasm. Six patients required active chest compressions and 39.71% of patients had their surgical procedure abandoned. Unplanned intensive care admissions occurred in 27.94%.

DISCUSSION

In order to reduce abandoned procedures, unplanned intensive care unit admissions, morbidity and mortality associated with CHL-induced anaphylaxis we recommend the following: rationalization of CHL-containing products, greater vigilance regarding subtle symptoms of CHL allergy, appropriate investigation of these symptoms and a greater awareness of CHL-containing products. Lastly, we outline the appropriate investigations and highlight the need for meticulous documentation in those who are CHL allergic.

Standardized testing with chlorhexidine in perioperative allergy--a large single-centre evaluation

BACKGROUND

Perioperative allergic reactions to chlorhexidine are often severe and easily overlooked. Although rare, the prevalence remains unknown. Correct diagnosis is crucial, but no validated provocation model exists, and other diagnostic tests have never been evaluated. The aims were to estimate (i) the prevalence of chlorhexidine allergy in perioperative allergy and (ii) the specificity and sensitivity for diagnostic tests for chlorhexidine allergy.

METHODS

We included all patients investigated for suspected perioperative allergic reactions in the Danish Anaesthesia Allergy Centre during 2004-2012. The following tests were performed: specific IgE (Immunocap® ; Phadia AB, Sweden), histamine release test (HR) (RefLab ApS, Denmark), skin prick test (SPT) and intradermal test (IDT). Positivity criteria were as follows: specific IgE >0.35 kUA/l; HR class 1-12; SPT mean wheal diameter ≥3 mm; IDT mean wheal diameter ≥ twice the diameter of negative control. Chlorhexidine allergy was post hoc defined as a relevant clinical reaction to chlorhexidine combined with two or more positive tests. Based on this definition, sensitivity and specificity were estimated for each test.

RESULTS

In total, 22 of 228 patients (9.6%) met the definition of allergy to chlorhexidine. Estimated sensitivity and specificity were as follows: specific IgE (sensitivity 100% and specificity 97%), HR (sensitivity 55% and specificity 99%), SPT (sensitivity 95% and specificity 97%) and IDT (sensitivity 68% and specificity 100%).

CONCLUSIONS

In patients investigated for suspected perioperative allergic reactions, 9.6% were diagnosed with allergy to chlorhexidine. Using our definition of chlorhexidine allergy, the highest combined estimated sensitivity and specificity was found for specific IgE and SPT.

Chlorhexidine and hypersensitivity reactions in dentistry

Immunological reactions to chlorhexidine, including allergy (Type I hypersensitivity) and allergic contact dermatitis/stomatitis (Type IV hypersensitivity), have been recognised for many years. This potential safety issue, however, is not well known within dentistry. The purpose of this paper is to alert dentists and dental care professionals to the potential of chlorhexidine in causing hypersensitivity reactions and to consider this possibility if unexplained hypersensitivity reactions occur.

Severe anaphylactic reaction to chlorhexidine during total hip arthroplasty surgery. A case report

Two consecutive hip surgery procedures in the same patient were aborted following a severe anaphylactic reaction of the patient. After the second procedure, the patient was diagnosed to be allergic to chlorhexidine, a component of the gel used to insert a urinary catheter. Chlorhexidine allergy is rare, and the delayed presentation may make it easy to overlook. In hip arthroplasty surgery, this may result in an abandoned procedure and the need for re-operation.

Chlorhexidine - Pharmacology and Clinical Applications

chlorhexidine is a widely used skin antisepsis preparation and is an ingredient in toothpaste and mouthwash. It is an especially effective antiseptic when combined with alcohol. Its antimicrobial effects persist because it is binds strongly to proteins in the skin and mucosa, making it an effective antiseptic ingredient for handwashing, skin preparation for surgery and the placement of intravascular access. Catheters impregnated with chlorhexidine and antimicrobial agents can reduce the incidence of catheter-related bloodstream infections. Contact dermatitis related to chlorhexidine is not common in health care workers. The incidence of contact dermatitis to chlorhexidine in atopic patients is approximately 2.5 to 5.4%. Acute hypersensitivity reactions to chlorhexidine are often not recognised and therefore may be underreported. This review discusses the pharmacology, microbiology, clinical applications and adverse effects of chlorhexidine.

Chlorhexidine in urethral gel: Does it cause pain at flexible cystoscopy?

OBJECTIVES

To investigate the effect of chlorhexidine gluconate in urethral local anesthetic gel on patients undergoing outpatient flexible cystoscopy. We postulated that chlorhexidine was contributing to the pain and urgency that occurs during and after cystoscopy.

METHODS

A prospective randomized single-blinded study was conducted. A total of 141 patients undergoing outpatient flexible cystoscopy participated in the study. They were randomized to receive 10 mL of 2% lignocaine gel with 0.05% chlorhexidine gluconate (group 1, n = 72) or 10 mL of 2% lignocaine and aqueous gel mixture (group 2, n = 69). Pain scores were recorded on a numerical visual analog scale from 0 to 10.

RESULTS

The groups were well matched for the purposes of comparison. The mean pain scores were not significantly different between groups 1 and 2 at the insertion of the scope (2.1 versus 2.2, P = 0.7), during cystoscopy (1.8 versus 1.9, P = 0.759), and immediately after cystoscopy (1.4 versus 0.8, P = 0.06). However, a significant difference was found in the mean pain scores between groups 1 and 2 during the first void (1.8 versus 1.0, P = 0.031) and after the first void (2.4 versus 1.2, P = 0.007). A significant increase occurred in the reported levels of urgency after cystoscopy in group 1 (P = 0.018). No difference was found in the level of culture-proven symptomatic infection.

CONCLUSIONS

Chlorhexidine appears to contribute to significant levels of pain and urgency after outpatient flexible cystoscopy.

Anaphylaxis to an urethral lubricant: chlorhexidine as the "hidden" allergen

We report on a severe allergic reaction during urethral catheterisation, initially erroneously attributed to natural rubber latex (NRL). However, the negative investigations for latex, the uneventful further applications of NRL, the positive skin test and basophil activation test for chlorhexidine strongly support diagnosis of chlorhexidine anaphylaxis. This case illustrates that it is not widely appreciated that "innocent" products such as urethral lubricants may elicit serious life-threatening reactions. Careful inspection of the medical records is once again re-emphasised to be mandatory in order to avert subsequent anaphylaxis.

Allergy to chlorhexidine gluconate in urethral gel: report of four cases and review of the literature

Chlorhexidine is a bis-biguanide molecule widely used in many preparations as a disinfectant and an antiseptic. We describe four confirmed cases of allergy to chlorhexidine gluconate in urethral gel and review the existing published reports. Pertinent issues in the treatment and investigation of these patients are discussed.

Anaphylaxis to chlorhexidine. Case report. Implication of immunoglobulin E antibodies and identification of an allergenic determinant

BACKGROUND

There are many reports of allergic reactions, including anaphylaxis, following exposure to chlorhexidine. Reactions may occur via contact with the skin and mucous membranes or from catheters treated with the antibacterial agent. Apart from implicating chlorguanide in immunoglobulin (Ig) E antibody-binding studies on serum from an anaphylactic patient, little work has been done on the molecular basis of recognition of the agent in sensitive subjects.

OBJECTIVES

The molecular basis of IgE-binding to chlorhexidine was closely examined with the view of defining its fine structural recognition features by antibodies from a subject who experienced anaphylaxis following contact with the antiseptic.

METHODS

Tryptase determinations, different drug-solid phases, immunoassays and quantitative hapten inhibition studies with chlorhexidine and selected structural analogues were employed together with serum from the anaphylactic patient. Results were analysed to define the complete drug allergenic determinant and to identify the important structural features complementary to the IgE antibody combining sites.

RESULTS

The subject's serum tryptase levels sampled after the reaction were elevated and employment of a chlorhexidine-EA Sepharose solid phase showed the presence of serum IgE antibodies to the drug. Lack of inhibition by 4-chlorophenol and other selected substituted phenyl compounds showed that the terminal groups at each end of the chlorhexidine molecule, alone, did not account for antibody recognition of the antibacterial agent. Although chlorguanide and alexidine, the structures of which each comprise part of the chlorhexidine molecule, showed significant inhibition of the binding of IgE antibodies to chlorhexidine, neither compound was as potent an inhibitor as chlorhexidine itself. Two molecules of chlorguanide make up the symmetrical molecule of chlorhexidine while the interior structure of alexidine (that is excluding the terminal 2-ethylhexyl groups) is identical to part of the chlorhexidine molecule.

CONCLUSIONS

Taken together, for this patient, these results lead to the conclusion that the whole chlorhexidine molecule is complementary to the IgE antibody combining sites and that the 4-chlorophenol, biguanide and hexamethylene structures together comprise the allergenic determinant. Hence, like one of the trimethoprim determinants identified, but unlike most drug allergenic determinants identified so far, the chlorhexidine allergenic determinant identified here encompasses the entire molecule.

Oral microflora as a cause of endocarditis and other distant site infections

Bacteremia originating from the oral cavity is common, but the role of bacteremia in the genesis of infective endocarditis and other distant site infections is unclear. Only a small percentage of oral flora have been associated with distant site infection. Important issues remain unresolved concerning the identification of patients at risk, the relative risk from invasive dental procedures versus naturally occurring bacteremia, and the impact of prophylactic antibiotics on the incidence, nature, magnitude, and duration of bacteremia from the oral cavity. This article addresses the controversies in infection management in patients at risk for distant site infection.