IU/L) levels were observed (Fig. 1d). Based on the patient's clinical course, in which no treatments other than the scabies treatment were introduced, the improvement of his skin symptoms and reductions in his serum TARC and IgE levels were considered to have been due to the scabies treatment. There are two common subtypes of scabies: classic and crusted scabies. 1,5 The skin manifestations of classic scabies include burrows and erythematous papules/nodules. Severe and persistent pruritus is a hallmark of scabies. 6 Hashimoto et al. 6 reported that Th2 immunity predominates in human ordinary scabies lesions and is accompanied by the massive infiltration of interleukin (IL)-31 (+) M2 macrophages and epidermal expression of thymic stromal lymphopoietin and periostin (TSLP). Eosinophils are one of the first cell types attracted to tissue sites affected by localized allergic inflammation, and they secrete Th2-inducing cytokines (IL-4 and IL-13), which affect resident dendritic cells (DCs), enhancing DC activation and promoting a Th2-inducing phenotype. 7,8 In our case, a histological examination revealed the massive infiltration of eosinophils and indicated that Th2 immunity was involved in upregulating the patient's serum TARC levels. Interestingly, his serum TARC levels decreased more markedly than his serum IgE levels after treatment. Serum TARC levels might reflect treatment efficacy more closely than serum IgE levels and, hence, could be considered as a potential biomarker. Further, as scabies is frequently misdiagnosed as AD or PN and treated with topical corticosteroids, which masks the condition, elevated serum TARC levels could further delay diagnosis. Thus, clinicians must consider scabies when examining patients with pruritic nodules who exhibit elevated serum TARC levels, and the serum TARC level might be a useful marker of the efficacy of treatments for scabies. Acknowledgement The patients in this manuscript have given written informed consent to publication of their case details.