D3.320 - Anaphylaxis by Chlorhexidine: A case series
Background
Chlorhexidine is a widely used antiseptic agent in hospital settings and in everyday life. It is present in a variety of personal care and oral hygiene products allowing frequent re-exposure, which is usually well tolerated. We describe the clinical profile of four cases of anaphylaxis caused by topical exposure to chlorhexidine.
Method
This case series included all patients diagnosed with Chlorhexidine-induced Anaphylaxis in two Navarre hospitals between 2018-2025, identified through medical records search. The diagnostic workup comprised a detailed clinical history, skin prick tests, serum tryptase measurements and chlorhexidine-specific IgE immunoassay.
Results
A total of 74534 of new patients were assessed in our departments between 2018-2025, 12 (0,01%) were diagnosed of chlorhexidine allergy, 4 of them (33%) with chlorhexidine anaphylaxis.
Four male patients were included with a median age: 13.5 (IQR 12-38.5), 3 patients (75%) developed anaphylaxis after a topical chlorhexidine application for minor skin wounds in a domiciliary setting. One patient (25%, 63 y.o), experienced a reaction in a medical setting following a bladder catheterization. All the patients developed symptoms within 30 minutes after exposure. Anaphylaxis severity range from mild-moderate reactions in three patients (75%) to anaphylactic shock requiring orotracheal intubation in the older patient.
Skin prick testing for chlorhexidine showed a sensitivity of 100%, while chlorhexidine-specific IgE had a sensitivity of 75% (IC 95%: 19,4-99.4). None of the patients reported previous reactions with chlorhexidine and baseline tryptase levels were normal in all cases.Table 1.
|
Age |
Sex |
Exposure |
Use |
Setting |
Onset |
Anaphylaxis |
Urticaria |
Respiratory compromise |
Cardiovascular collapse |
History of atopy |
History of previous reactions |
Prick/ intradermal test |
IgE Chlorhexidine |
Acute tryptase |
Basal tryptase |
|
11 |
M |
Topical |
Superficial wound |
domiciliary |
<30 m |
Y |
Y |
N |
Y |
N |
NR |
Positive |
0,10 kU/L |
|
4,7ug/L |
|
13 |
M |
Topical |
Superficial wound |
domiciliary |
<30 m |
Y |
Y |
N |
N |
N |
NR |
Positive |
2,76 kU/L |
12,8ug/L |
3,7ug/L |
|
14 |
M |
Topical |
Superficial wound |
domiciliary |
<30 m |
Y |
Y |
Y |
N |
Y |
NR |
Positive |
1,33 kU/L |
|
3,9ug/L |
|
63 |
M |
Topical mucosa |
Bladder catheter |
medical |
<30 m |
Y |
Y |
Y |
Y |
N |
NR |
Positive |
22,1 kU/L |
18,1ug/L |
5,5ug/L |
Conclusion
In this small case series, epidermal exposure to chlorhexidine was associated with mild to moderate anaphylaxis, whereas mucosal exposure during a urological procedure resulted in anaphylactic shock.
Skin prick testing and chlorhexidine specific-IgE proved useful diagnostic tools.
Despite the low frequency, given the ubiquitous use of Chlorhexidine, it is essential to recognize it as a potential etiological agent of anaphylaxis.
