Background: Microvesicular eczema (acute/subacute dermatitis) is a frequent dermatological condition characterized by pruritus, erythema, and vesicle formation. While often treated symptomatically, the underlying role of delayed-type hypersensitivity to contact allergens remains underdiagnosed in the Fergana Valley region. This study aims to identify the prevalence of contact sensitization in patients with microvesicular eczema and determine the spectrum of causative allergens. Methods: A prospective clinical study involving 150 patients with persistent microvesicular eczema was conducted. All participants underwent epicutaneous patch testing using the European Standard Series (ESS) of allergens. Reactions were read at 48, 72, and 96 hours according to ICDRG criteria. A control group of 50 healthy individuals was included for comparison. Results: Positive patch test reactions were observed in 68.0% of patients, significantly higher than in the control group (12.0%, p < 0.001). The most frequent allergens identified were Nickel sulfate (28.7%), Potassium dichromate (14.0%), and Cobalt chloride (11.3%). A strong correlation was found between "wet work" occupations and sensitization to preservatives. Conclusion: Contact allergens play a pivotal etiological role in the pathogenesis of microvesicular eczema. Routine patch testing is essential for identifying specific triggers, enabling targeted avoidance strategies, and preventing chronicity.

Microvesicular eczema, allergic contact dermatitis, patch testing, nickel sensitization, skin barrier, occupational dermatology.

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