Cross With Caution: Antibiotic Cross-Reactivity and Co-Reactivity Patterns in Severe Cutaneous Adverse Reactions

Infliximab-induced symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) in a patient with ulcerative colitis

Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) is a rare, symmetrical skin eruption triggered by various medications, predominantly beta-lactam antibiotics. We report the case of a 69-year-old male with moderate-to-severe ulcerative colitis who developed SDRIFE following the seventh intravenous administration of infliximab. The patient presented with symmetrical, pruritic erythema in the cubital and popliteal fossae, groins, gluteal and retroauricular regions without systemic involvement. Skin biopsy showed mild exocytosis of T lymphocytes in the epidermis and dense superficial perivascular CD3+ and CD4+ infiltration, consistent with a type IVa hypersensitivity reaction. The patient responded well to a regimen of systemic antihistamines, topical corticosteroids and tacrolimus ointment, with complete regression of lesions within one week. Despite mild recurrences of SDRIFE after each infliximab administration, the therapy was not discontinued due to the mild nature of the reaction and favourable prognosis. The authors are not aware of previously published cases of type IVa SDRIFE induced by infliximab. Unlike previous reports of severe type IVc SDRIFE reactions requiring discontinuation of infliximab, our case highlights the predominance of CD4+ cells, which may explain the mild clinical course. Understanding the underlying immunologic mechanisms of infliximab-induced SDRIFE could affect treatment decisions and prevent unnecessary discontinuation of effective therapies.

Distinguishing DRESS syndrome from drug rash and eosinophilia: Beyond RegiSCAR criteria

Background

Diagnosing drug reaction with eosinophilia and systemic symptoms (DRESS) can be challenging.

Objectives

We sought to identify clinical and laboratory features outside of the Registry of Severe Cutaneous Adverse Reaction (RegiSCAR) criteria that distinguish patients with probable DRESS (RegiSCAR ≥ 4) from those with drug rash and eosinophilia (DRE).

Methods

Using international coding classifications of drug-induced fever, generalized skin eruption due to medications, and eosinophilia, a retrospective audit from 2008 to 2023 of hospitalized patients was performed.

Results

Forty-four cases of DRESS were compared to 80 cases of DRE. In addition to the RegiSCAR distinguishing factors for DRESS were longer drug latency before symptom onset (median 21 vs 5 days, P < .001) and higher alanine transaminase levels (increase by a factor of 2.49 [95% confidence interval, 1.56, 4.00; P = .009]). Follow-up (mean 5.67 years) revealed a low rate of statewide drug alert reporting (29.6%) and drug allergy testing in DRESS (20.5%). Inadvertent reexposure to a culprit or structurally related drug resulted in recurrent DRESS in 3 patients (7.5%), and tolerance of structurally related drugs occurred in 8 patients (17.5%).

Conclusion

In this large study evaluating DRE patients whose disease does not meet the RegiSCAR criteria for DRESS, we found that additional factors outside the RegiSCAR criteria may help clinicians differentiate DRESS, which is critical for optimal and timely patient management. Our study also highlights the need for development of local protocols to ensure appropriate allergy labeling and testing are performed to prevent recurrent DRESS.

Stevens-Johnson Syndrome in a Patient on Concomitant Treatment with Levetiracetam and Trimethoprim/Sulfamethoxazole

BACKGROUND Trimethoprim/sulfamethoxazole and levetiracetam are commonly prescribed medications in the treatment of infections and seizures, respectively. Despite their known efficacy, each has a reputation for triggering severe and sometimes life-threatening cutaneous adverse drug reactions such as Stevens-Johnson syndrome and toxic epidermal necrolysis. Although the mechanism of such cutaneous adverse drug reactions cannot be fully explained, it is thought to be a type IV T cell and NK cells-mediated hypersensitivity reaction that leads to keratinocyte apoptosis and epidermal necrosis. It is also thought that cutaneous adverse drug reactions are also linked to a patient's genetic predispositions, especially the human leukocyte antigens profiles and the N-acetyl transferase 2 phenotypic variation. CASE REPORT We describe a case of Stevens-Johnson syndrome in a severely ill 51-year-old man who was treated in an outside health care facility simultaneously with Trimethoprim/sulfamethoxazole and levetiracetam. The patient presented to our Emergency Department with Stevens-Johnson syndrome believed to possibly be related to the combination of these 2 agents. CONCLUSIONS The concomitant use of Trimethoprim/sulfamethoxazole and levetiracetam might have been responsible for heightening the potential of these 2 medications to trigger an unfortunate adverse drug reaction, but no formal culprit was able to be identified and no in vivo study was performed, due to ethical considerations. Thus, through this case report we strive to increase awareness of the potential risk of simultaneously prescribing these 2 medications.

Patch testing in Drug reaction with eosinophilia and systemic symptoms (DRESS): a literature review

The literature on positive patch test results in drug reaction with eosinophilia and systemic symptoms (DRESS) is reviewed. 105 drugs were identified that have together caused 536 positive patch tests in 437 patients suffering from DRESS. By far most reactions (n=145) were caused by carbamazepine, followed by amoxicillin, isoniazid, phenytoin, ethambutol, fluindione, phenobarbital, rifampicin, and ceftriaxone; 43 drugs each caused a single case only. The drug classes causing the highest number of reactions are anticonvulsants (39%), beta-lactam antibiotics (20%), antituberculosis agents (11%), non-beta-lactam antibiotics (6%) and iodinated contrast media (5%). The sensitivity of patch testing (percentage of positive reactions) is high for anticonvulsants (notably carbamazepine), beta-lactam antibiotics (notably amoxicillin) and possibly iodinated contrast media. Allopurinol and sulfasalazine frequently cause DRESS, but never give positive patch tests. Patch testing in DRESS appears to be safe, although mild recurrence of DRESS symptoms, mostly skin reactions, may not be rare. Multiple drug hypersensitivity was found to occur in 16% of all patients, but it is argued that the true frequency is (far) higher. Clinical aspects of DRESS, including diagnosing the disease and identifying culprit drugs (patch tests, intradermal tests, in vitro tests, challenge tests) are also provided, emphasizing the role of patch testing. This article is protected by copyright. All rights reserved.