Role of basal sweating in maintaining skin hydration in the finger: A long-standing paradox in dry skin resolved.

A long-standing paradox in dermatology is why skin dehydration in the fingers can be triggered by repeated water exposure despite the action of water to hydrate skin tissue. Potential clues might be provided by identifying a mechanism through which water is held in the skin of the fingers. We speculated that this mechanism would be impaired after repeated water exposure. Here, we investigated whether there might be glabrous skin-specific water-holding machinery and whether this machinery might be impaired in dry skin/hand eczema. We examined this by using an impression-mould technique, allowing for an accurate quantification of sweat gland/duct activity and optical coherence tomography. Unlike in hairy skin, sweat pores were rarely detected at the folds of the finger at baseline. Surprisingly, after water exposure, sweat pores at the folds opened and those at the ridges closed in healthy controls (HCs). Sweating in the dermal folds of the hands correlated with skin hydration, and decreased in dry skin/hand eczema, suggesting that its impairment may be one of the causes of dry skin. After repeated water exposure, basal sweating response at the folds was exhausted in patients with dry skin/hand eczema as well as HCs. This exhaustion was rescued by exposing individuals to high humidity. Basal sweating defects would be a target for dry skin/hand eczema. Maintaining basal sweating responses in the finger is the best preventive measures in achieving prevention of dry skin/hand eczema.

Prurigo nodularis as a sweat gland/duct-related disorder: resolution associated with restoration of sweating disturbance.

Little attention has been given to the involvement of sweat glands/ducts in the pathogenesis of prurigo nodularis (PN). According to recent studies, PN is likely to develop under conditions characterized by dry skin, such as atopic dermatitis (AD), suggesting a strong impact of skin dryness on PN development. No therapeutic modalities produced complete resolution of PN without exacerbations. We previously reported that increases in skin dryness by sweating disturbance could initiate the development of AD. We investigated whether sweating responses were impaired in refractory PN lesions; and, if so, we asked whether the PN lesions could resolve by restoring sweating disturbance. Using the impression mold technique, which allows an accurate quantification of individual sweat gland/duct activity, we examined basal sweating under quiescent conditions and inducible sweating responses to thermal stimulus in PN lesions and normal-appearing skin in the same patients before and after treatment with a moisturizer or topical corticosteroids. Sweating disturbance, either basal or inducible, was most profoundly detected in the "hub" structure corresponding to the center of PN papule before the treatment. This sweating disturbance was immunohistochemically associated with the leakage of sweat into the dermis. This disturbance was restored by treatment with a moisturizer. Our limitations include a relatively small patient cohort and lack of blinding. Sweating disturbance could be one of the aggravating factors of PN development. Refractory PN with low skin hydration may resolve by restoring sweating disturbance.

Japanese version of the early psoriatic arthritis screening questionnaire (EARP).

The early psoriatic arthritis screening questionnaire (EARP) is a simple and fast method for the identification of arthritis in patients with psoriasis. We established the Japanese version of the EARP (J-EARP) questionnaire, which includes 10 items with two choices for each. This study aimed to evaluate the utility of the J-EARP questionnaire. A total of 90 psoriasis patients, 19 psoriatic arthritis (PsA) patients and 71 psoriasis patients without joint involvement, were administered the J-EARP questionnaire. The diagnostic accuracy of the J-EARP questionnaire for the diagnosis of PsA and early-stage PsA was compared by receiver-operator curve (ROC) analysis. The J-EARP questionnaire showed similar ROC characteristics to those of the original version of the EARP (specificity 97.2% and 91.6% and sensitivity 97.2% and 85.2%, respectively) in PsA patients using the cut-off value of 3 for the J-EARP questionnaire, which was the same as that used for the original EARP questionnaire. The scores of the J-EARP questionnaire in early-stage PsA patients (<1 year from onset) were significantly higher than in those of psoriasis patients, but not lower than in those of later stage (≥1 year from onset) PsA patients. The J-EARP questionnaire is simple and fast to administer and has been proven to be robust for the identification of PsA. The J-EARP questionnaire is a useful diagnostic tool for early-stage PsA patients.

Adverse effects of methotrexate in three psoriatic arthritis patients.

Methotrexate, a folic acid analogue with anti-proliferative and anti-inflammatory effects, is commonly used to treat patients with severe destructive psoriatic arthritis and has considerable efficacy. Combined anti-tumor necrosis factor and MTX therapy result in less treatment discontinuation due to adverse events. Despite its efficacy, MTX may result in adverse effects including hepatic, pulmonary, and renal toxicity as well as lymphoproliferative disorders and predisposition to infection. We herein report rare adverse effects of MTX treatment, specifically asymptomatic pulmonary tuberculosis, renal cell carcinoma, and lateral uveitis, in three psoriatic arthritis patients treated with MTX. MTX is an important drug for the treatment for psoriatic arthritis patient, but an awareness of the possible adverse effects is needed.

A case of psoriasis verrucosa successfully treated with adalimumab.

We herein report a case of psoriasis verrucosa that was successfully treated with adalimumab. A 55-year-old Japanese male had a five-year history of psoriasis vulgaris treated with topical agents. His past history included atypical psychosis treated with lithium carbonate and obesity. Despite treatment, verrucous scales developed on erythematous plaque. After treatment with adalimumab, these improved remarkably, and the patient's Psoriasis Area and Severity Index score decreased from 16.2 to 3.7.