Purpura after application of EMLA cream in two children

Dermatoscope for the diagnosis of erythema with purpura induced by lidocaine/prilocaine cream: A case report

BACKGROUND

Lidocaine/prilocaine (EMLA) cream is a local anesthetic that is applied to the skin or mucosa during painful therapeutic procedures with few reported side effects.

CASE SUMMARY

Here, we report the use of dermatoscopy to identify a case of erythema with purpura, a rare side effect, after the application of 5% EMLA cream.

CONCLUSION

We conclude that erythema with purpura is caused by irritation and toxicity associated with EMLA, but the specific mechanism by which the toxic substance affects skin blood vessels is unclear. In response to this situation and for cosmetic needs, we recommend tranexamic acid, in addition to routine therapy, to prevent changes in pigmentation in patients with dermatitis.

Allergy to Local Anesthetics is a Rarity: Review of Diagnostics and Strategies for Clinical Management

Local anesthetics (LA) are commonly used in procedures and in topical agents for pain management. With the increasing use of LA drugs, the management of LA reactions is more frequently encountered in the office and in operating rooms. True allergic reactions involving IgE-mediated reactions and anaphylaxis are rare; they have only been identified in case reports and account for less than 1% of adverse LA reactions. Most reactions are non-allergic or are a result of hypersensitivity to other culprits such as preservatives, excipients, or other exposures. LA reactions that are misclassified as true allergies can lead to unnecessary avoidance of LA drugs or delays in surgical procedures that require their use. A detailed history of prior LA reactions is the first and most crucial step for understanding the nature of the reaction. Reactions that are suspicious for an immediate hypersensitivity reaction can be evaluated with skin prick and intradermal testing with subsequent graded challenge. Reactions that are suspicious for a delayed hypersensitivity reaction can be evaluated with patch testing.

Randomized, double-blind, phase III clinical study of a novel nanotechnological topical anesthetic formulation containing lidocaine 25 mg/g and prilocaine 25 mg/g (nanorap) in skin phototypes I-III patients with ablative fractional CO2 laser treatment indication in the forehead

BACKGROUND AND OBJECTIVES

Nanotechnology may increase the speed of penetration into the skin. This study evaluated the efficacy, safety, and pharmacokinetics of a novel topical anesthetic nanocapsule formulation (2 g) containing 2.5% lidocaine and 2.5% prilocaine (nanorap-test formulation) compared to placebo (control formulation) in skin types I-III patients of both sexes submitted to the ablative fractional CO₂ laser treatment.

METHODS

The patients (n = 120) included in this double-blind, single-center, randomized trial, received topical application of 2 g of the test formulation (50 mg lidocaine + 50 mg prilocaine) and placebo on the forehead region. Efficacy was assessed as pain sensation in four quadrants of each side of the forehead using a visual analogue scale immediately (0 min) and at 30, 60, and 90 minutes after laser application compared to placebo. The safety and tolerability of the test product were evaluated based on the occurrence of systemic adverse events as well as the occurrence of immediate and late skin reactions. Pharmacokinetic evaluation was performed in plasma of eight patients using a validated LC-MS/MS method for drugs quantification.

RESULTS

Nanorap induced a clinically significant reduction in the pain assessment at all evaluated times (57.2%, 41.6%, 38.6%, and 37.3% at 0, 30, 60, and 90 minutes after drug application, respectively. Mean values of C_max were 14.20 and 5.36 ng/ml and t_max were 3.5 and 1.8 hour for lidocaine and prilocaine, respectively. No systemic adverse events were observed.

CONCLUSION

The nanorap formulation demonstrated a clinically and statistically significant efficacy providing analgesia after the ablative fractional CO₂ laser therapy in the investigated patients, when compared to placebo. The product also presented good safety and tolerability. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Comparative evaluation of Myolaxin and EM LA cream for attenuation of venous cannulation pain: A prospective, randomised, double blind study

We evaluated the efficacy of topical Myolaxin (capsaican ointment, Geno, Mumbai) ointment over EMLA (eutectic mixture of lignocaine, prilocaine; Neon, Goa) cream for attenuating venous cannulation pain in this prospective, randomised, double blind study. Sixty adult patients undergoing elective laparoscopic cholecystectomy were randomly assigned into two equal groups. Group I (EMLA) received EMLA cream, whereas Group II (Myolaxin) received Myolaxin ointment. For both groups the cream was applied at the venous cannulation site (dorsum of the non-dominant hand) one hour prior to venous cannulation and was covered with an occlusive dressing. Following venous cannulation patients were asked if they felt pain during venous cannulation. If the answer was yes, they were asked to rate the severity of venous cannulation pain using a Visual Analogue Scale (VAS) of O-10. The incidence of venous cannulation pain was similar between groups: in the EMLA group 65% (18/28) compared to 67% (20/30) in the Myolaxin group (P=0.19). The severity of pain (median VAS with inter quartile range) was also similar between the groups: in the EMLA group 1.5 (3) compared to 1.5 (2) in the Myolaxin group (P=0.46). As the topical application of Myolaxin ointment is cheaper than EMLA and has similar efficacy, it may be a suitable alternative for reducing the incidence and severity of venous cannulation pain.

Proposed ICDRG Classification of the Clinical Presentation of Contact Allergy

The International Contact Dermatitis Research Group proposes a classification for the clinical presentation of contact allergy. The classification is based primarily on the mode of clinical presentation. The categories are direct exposure/contact dermatitis, mimicking or exacerbation of preexisting eczema, multifactorial dermatitis including allergic contact dermatitis, by proxy, mimicking angioedema, airborne contact dermatitis, photo-induced contact dermatitis, systemic contact dermatitis, noneczematous contact dermatitis, contact urticaria, protein contact dermatitis, respiratory/mucosal symptoms, oral contact dermatitis, erythroderma/exfoliative dermatitis, minor forms of presentation, and extracutaneous manifestations.

Pseudo-Bullous Dermatosis Induced by Topical Anesthetic Agent-Clues to This Localized Toxic Reaction

Eutectic mixture of 2.5% lidocaine and 2.5% prilocaine (EMLA AstraZeneca, DE) is a widely used topical anesthetic cream for preprocedural cutaneous analgesia. In addition to potential clinical cutaneous and systemic adverse effects, EMLA may also induce microscopic changes detectable by light and electron microscopy leading to difficulty in accurate diagnosis. We report the case of a biopsy demonstrating EMLA-induced histopathologic changes. The biopsy was taken from the back of a 5-month-old infant and submitted to rule out psoriasis. Hematoxylin and eosin (H&E) staining of the biopsy demonstrated spongiosis and a noninflammatory subepidermal bulla, raising the histopathologic possibility of epidermolysis bullosa. Further investigation confirmed that EMLA was applied under occlusion before biopsy. A second biopsy without topical anesthetic did not demonstrate a bulla and supported the clinical diagnosis of psoriasiform dermatitis. Our case highlights the importance of awareness of EMLA-induced histopathologic changes to avoid potential misdiagnosis. The histopathologic findings of this case in conjunction with other previously reported cases of EMLA-induced bullae were analyzed. Vacuolization of the basal and suprabasilar layer, pallor and swelling of upper layer epidermal keratinocytes, a pauci-inflammatory cleavage beneath or within the basal layer, basophilic granular karyorrhectic debris in the subepidermal cleft, and congestion of papillary dermal vessels characterized the biopsy findings of this localized adverse reaction.

Lidocaine inhibits staphylococcal enterotoxin-stimulated activation of peripheral blood mononuclear cells from patients with atopic dermatitis

Atopic dermatitis (AD) is an inflammatory, chronically relapsing, pruritic skin disease and lesions associated with AD are frequently colonized with Staphylococcus aureus (S. aureus). Activation of T cells by staphylococcal enterotoxins (SE) plays a crucial role in the pathogenesis of AD. Previous studies have demonstrated that lidocaine could attenuate allergen-induced T cell proliferation and cytokine production in peripheral blood mononuclear cells (PBMCs) from asthma patients. The purpose of this study was to investigate the effects of lidocaine on SE-stimulated activation of PBMCs from AD patients. PBMCs were isolated from ten AD patients and stimulated by staphylococcal enterotoxin A (SEA) or staphylococcal enterotoxin B (SEB) in the presence or absence of lidocaine in various concentrations. Cellular proliferation and the release of representative TH1- and TH2-type cytokines were measured. The effect of lidocaine on filaggrin (FLG) expression in HaCaT cells co-cultured with SE-activated PBMCs was also examined. Our results demonstrated that lidocaine dose-dependently inhibited the proliferative response and the release of IL-4, IL-5, IL-13, TNF-α, and IFN-γ from SEA- and SEB-stimulated PBMCs and also blocked the down-regulation of FLG expression in HaCaT cells co-cultured with SEA- and SEB-activated PBMCs. These results indicate that lidocaine inhibited SEA- and SEB-stimulated activation of PBMCs from patients with AD. Our findings encourage the use of lidocaine in the treatment of AD.