'Deep impact' contact allergy after subcutaneous injection of local anesthetics

Differential diagnosis of late-type reactions to injected local anaesthetics: Inflammation at the injection site is the only indicator of allergic hypersensitivity

BACKGROUND

Anaphylaxis-like reactions developing within a few minutes are the most frequent complications of subcutaneous or submucosal injections of local anaesthetics (LAs), and topically applied LAs are potential contact allergens. In addition, injected LAs have been reported to induce delayed reactions, including local inflammation at the injection site, and various general symptoms.

OBJECTIVES

To assess the frequency and symptoms of late-type hypersensitivity occurring several hours after LA injections.

METHODS

We retrospectively evaluated clinical data and test results from all patients referred to our allergy clinic in a period of 20 years for diagnostic work-up of LA-associated late-type reactions.

RESULTS

Of 202 patients reporting symptoms with onset at least 1 hour after LA injection, 40 had cutaneous inflammation confined to the injection site, and 162 reported various systemic symptoms. LA hypersensitivity could be excluded in all patients with systemic complaints by means of skin testing and subsequent subcutaneous provocation. In 8 of the 40 patients (20%) with local inflammatory reactions, late-type allergic LA hypersensitivity was confirmed.

CONCLUSIONS

Late-type LA allergy commonly causes inflammatory skin reactions confined to the injection site. Conversely, LAs are highly unlikely to trigger delayed systemic symptoms such as urticarial or exanthematous skin eruptions.

Sources of sensitization, cross-reactions, and occupational sensitization to topical anaesthetics among general dermatology patients

BACKGROUND

Contact sensitization to local anaesthetics is often from topical medicaments. Occupational sensitization to topical anaesthetics may occur in certain occupations.

OBJECTIVES

The aim of the study was to analyse the occurrence of contact sensitization to topical anaesthetics in general dermatology patients.

PATIENTS AND METHODS

Patch testing with topical anaesthetics was carried out in 620 patients. Possible sources of sensitization and the clinical histories of the patients are analysed.

RESULTS

Positive patch test reactions to one or more topical anaesthetics were seen in 25/620 patients. Dibucaine reactions were most common (20/25), and lidocaine sensitization was seen in two patients. Six patients had reactions to ester-type and/or amide-type anaesthetics concurrently. Local preparations for perianal conditions were the most common sensitizers. One patient had developed occupational sensitization to procaine with multiple cross-reactions and with concurrent penicillin sensitization from procaine penicillin.

CONCLUSIONS

Dibucaine-containing perianal medicaments are the major source of contact sensitization to topical anaesthetics. Although sensitization to multiple anaesthetics can be seen, cross-reactions are possible. Contact sensitization to lidocaine is not common, and possible cross-reactions should be determined when reactions to lidocaine are seen. Occupational procaine sensitization from veterinary medicaments is a risk among animal workers.

Hypersensitivity to local anaesthetics--update and proposal of evaluation algorithm

Local anaesthetics (LA) are widely used drugs. Adverse reactions are rare but may be caused by delayed-type hypersensitivity reactions and probably also immediate-type reactions. As it is not always easy to clinically differ between these subtypes, allergy skin testing should be considered. Although numerous test protocols have been published, how patients with hypersensitivity reactions to LA are ideally evaluated remains a topic of discussion. This review attempts to generate a comprehensive update on allergic reactions to LA and to present an algorithm that can be used for the evaluation of patients suspected with immediate- and delayed-type immune reactions. Literature was examined using PubMed-Medline, EMBASE, Biosis and Science Citation Index. Based on the literature, the proposed algorithm may safely and rapidly distinguish between immediate-type and delayed-type allergic immune reactions.

Labial edema following treatment of condyloma acuminata with CO(2) laser in an adolescent: a case report and literature review

PURPOSE

To describe a case of bilateral labial edema in an adolescent patient and review the literature on this rare occurrence.

MATERIAL

A 16-year-old girl was treated for widespread genital condyloma acuminata with CO(2) laser under general anesthesia and local lidocaine injections. Severe bilateral labial edema occurred after 48 hours.

RESULTS

Lidocaine and Latex dermal patch tests for delayed hypersensitivity were negative. The edema resolved following treatment with local ice packs and magnesium sulfate compresses for 2 weeks.

CONCLUSION

This is the first description of severe bilateral labial edema after CO(2) laser treatment for condyloma acuminata. We suggest that transient local lymphatic obstruction was the reason for this complication. The literature on this rare occurrence is reviewed.

Lidocaine hypersensitivity after subconjunctival injection

CASE REPORT

We report a rare case of hypersensitivity in a 63-year-old man who received subconjunctival lidocaine, cefazolin, and gentamicin for corneal abscess. Significant palpebral swelling and erythema were observed several hours after the injection. Nine months later, he received subconjunctival lidocaine, vanco-mycin, and ceftazidime for a new corneal abscess. After several hours, the eyelids were red and swollen, with mild blistering and scaling of the cheek. Two patch tests for lidocaine were negative. During follow-up, lateral tarsorrhaphy was performed under local anesthesia with lidocaine; erythema and swelling of eyelids and cheek appeared, resolving after several days.

COMMENTS

Sensitivity to lidocaine can appear after subconjunctival injection. Patch tests may be negative, but the allergy suspected by the recurrence of clinical signs after rechallenge with lidocaine. Ester anesthetics can be used for local anesthesia.

Contact urticaria from Emla cream

We report the first case of immediate-type hypersensitivity caused by Emla cream. A 55-year-old woman, after using Emla cream, went on to develop urticaria. An open test was positive to Emla cream. Patch tests and prick tests were performed with Emla cream, the components of Emla cream (lidocaine, prilocaine and castor oil) and other local anaesthetics. The patch test with lidocaine and the prick test with Emla cream were both positive. An intradermal test and subcutaneous administration of 3 anaesthetics that had negative patch tests and prick tests were performed and well tolerated, allowing their use. In the literature, anaphylactic reactions to lidocaine injections, delayed-type hypersensitivity after lidocaine subcutaneous injections and contact dermatitis from Emla cream have all been described. This first case of contact urticaria from Emla cream was due to lidocaine and did not show any cross-reaction with other local anaesthetics.