Kimie Takehara

Clinical significance of serum levels of soluble interleukin-2 receptor in patients with localized scleroderma

Summary Localized scleroderma has been reported to be accompanied by abnormal immune reactions, including autoantibody production and lymphocyte activation. Lymphocyte activation can be quantitatively detected by measuring soluble interleukin‐2 receptor (sIL‐2R) in serum samples. In this study, serum sIL‐2R levels were assayed by a sensitive enzyme‐linked immunosorbent assay, in 48 patients with localized scleroderma, in 20 with systemic sclerosis (SSc) and in 20 healthy controls. Serum levels of sIL‐2R were significantly higher in patients with localized scleroderma than in healthy controls. The serum levels of sIL‐2R were correlated with the number of sclerotic lesions, the number of involved areas, the levels of anti‐ssDNA, and the levels of antihistone antibody immunoglobulin M. Moreover, sIL‐2R levels in sera from patients with SSc were also significantly higher than in healthy controls. Elevated serum levels of sIL‐2R in localized scleroderma suggest that lymphocyte activation is one of the early processes in the development of this disease.

Aging enhances maceration-induced ultrastructural alteration of the epidermis and impairment of skin barrier function.

BACKGROUND Skin maceration is recognized as a risk factor for the development of certain skin lesions. In health care settings, incontinence-associated skin maceration is highly prevalent in the elderly. However, the effect of senescence on maceration has not been fully elucidated. OBJECTIVE To reveal the enhancement of the maceration-induced ultrastructural alteration and barrier function of the epidermis by aging. METHODS Skin maceration was reproduced by exposure to agarose gel in human and rat. The ultrastructural alterations in human and rat tissue were observed by transmission electron microscopy. The skin barrier function was evaluated by noninvasive methods in human, and by the transdermal penetration of small- and large-fluorescent molecules in rat. In order to reveal the effect of aging on the skin maceration, we compared these parameters between young and aged rats. RESULTS In macerated skin, we observed expansion of the interstices of the stratum corneum, spinosum, and basale of the epidermis; disruption of the intercellular lipid structure in the stratum corneum; a decreased number of cell processes in the stratum spinosum and basale. The transdermal penetration test in the rat using two types of fluorescein indicated that maceration disrupted skin barrier function. Furthermore, senescence-enhanced ultrastructural and functional alterations were revealed in the rodent studies. CONCLUSION This study demonstrates that aging enhances skin maceration. Considering that maceration is a risk factor for the skin damage, the development of technology to promote skin barrier recovery after maceration in the elderly is warranted.

Morphological pattern classification system for plantar thermography of patients with diabetes.

Background: A plantar temperature distribution can be obtained by thermography; however, the advantage has not been effectively utilized in the past. We previously proposed a classification method based on the angiosome concept, but the method was insufficient because it was too subjective and complicated for clinicians. In this study, we propose a new classification system of plantar forepart thermographic patterns using an image segmentation technique. Methods: A cross-sectional observational study was conducted including 32 healthy volunteers and 129 patients with diabetes mellitus (DM). Individual thermographic variations and trends were evaluated. A comparison was conducted between the patterns obtained by our previous angiosome-based research and the patterns found by the new classification system. Results: The system objectively found wider variations of the plantar forepart thermographic patterns in the patients with DM compared with those in the control subjects. In patients with DM, the system showed that the whole-high pattern was most frequent (46%), followed by the butterfly pattern (12%). In the control group, the butterfly pattern was most frequent (44%), followed by the whole-high pattern (19%). Both ankle and toe brachial indices were higher in feet with high temperature area in the inner side of the plantar. Conclusions: Thermographic patterns found by the new computer-based system were similar to those obtained in our previous subjective work. The classification system found forefoot-low pattern and tiptoe-low pattern objectively. The system based on infrared thermography will be a screening tool to assess circulatory status in daily foot care of patients with DM.

Screening for tinea unguium by Dermatophyte Test Strip

The direct microscopy, fungal culture and histopathology that are necessary for the definitive diagnosis of tinea unguium are disadvantageous in that detection sensitivity is affected by the level of skill of the person who performs the testing, and the procedures take a long time.

Shear Stress-Normal Stress (Pressure) Ratio Decides Forming Callus in Patients with Diabetic Neuropathy

Aim. Callus is a risk factor, leading to severe diabetic foot ulcer; thus, prevention of callus formation is important. However, normal stress (pressure) and shear stress associated with callus have not been clarified. Additionally, as new valuables, a shear stress-normal stress (pressure) ratio (SPR) was examined. The purpose was to clarify the external force associated with callus formation in patients with diabetic neuropathy. Methods. The external force of the 1st, 2nd, and 5th metatarsal head (MTH) as callus predilection regions was measured. The SPR was calculated by dividing shear stress by normal stress (pressure), concretely, peak values (SPR-p) and time integral values (SPR-i). The optimal cut-off point was determined. Results. Callus formation region of the 1st and 2nd MTH had high SPR-i rather than noncallus formation region. The cut-off value of the 1st MTH was 0.60 and the 2nd MTH was 0.50. For the 5th MTH, variables pertaining to the external forces could not be determined to be indicators of callus formation because of low accuracy. Conclusions. The callus formation cut-off values of the 1st and 2nd MTH were clarified. In the future, it will be necessary to confirm the effect of using appropriate footwear and gait training on lowering SPR-i.

Relationship between morphological characteristics and etiology of pressure ulcers in intensive care unit patients.

PURPOSE: Pressure ulcer (PU) prevention is crucial for critically ill patients in the intensive care unit, but etiologic factors leading to their development have not yet been completely elucidated. This study explores the relationships among etiologic factors, interventional nursing care, and morphological characteristics of PUs in intensive care unit patients. DESIGN: We used a qualitative exploratory method to link morphological characteristics of specific PUs to etiologic factors. METHODS: Details of individual PUs were described by sketching the PU photograph and categorized to characterize the morphology of PUs. After identification of characteristics, the development process was evaluated by in-depth review of medical records. RESULTS: The morphological characteristics of 30 PUs were organized into 4 categories. This process revealed a type of PU not previously described, which we labeled “leaf-type.” These PUs were located on the lower sacrum, rhombic-oval in shape, and characterized by purpura and PU wrinkles. Possible etiologic factors for the specific PUs were divided into 4 categories: (1) the occurrence of PU risk episodes, (2) failure of the peripheral circulation, (3) periods of critical immobility, and (4) position change techniques inducing skin deformation. CONCLUSION: PU can be categorized into 4 morphological types, including a new category of leaf-shaped PU. We found that frequently repeated position changes such as lateral tilt and repeated head elevation caused deformation of the sacral skin that may play a role in PU development.

Diagnosis of tinea pedis by the Dermatophyte Test Strip.

DEAR EDITOR, Tinea pedis is highly prevalent and is often seen in daily practice. However, it is difficult to diagnose tinea pedis visually because there are many similar diseases. Thus, a definitive diagnosis by mycological examination is necessary before the initiation of treatment for tinea pedis. Direct microscopy and fungal culture are used as test methods. However, direct microscopy has the disadvantage that the detection sensitivity is affected by the skill of the person who performs the test, while fungal culture takes 2–3 weeks for the identification of pathogenic fungi and has a low identification rate. The Dermatophyte Test Strip (JNC Corp., Tokyo, Japan) is a recently developed product that permits detection of mycotic antigens by immunochromatography in samples such as scales and nails. This test strip is likely to be useful clinically because it does not require special devices or skills, and can detect dermatophyte antigens from clinical samples in a short period of time. Compared with the standard method of direct microscopy, we have previously shown that the Dermatophyte Test Strip has sufficient sensitivity and specificity for the diagnosis of tinea unguium. There have also been some preliminary reports on the diagnosis of tinea pedis using the Dermatophyte Test Strip. In this study, we investigated, using scale samples, the capacity of the Dermatophyte Test Strip to detect tinea pedis. This test strip detects dermatophytic antigen by immunochromatography using monoclonal antibodies that react with dermatophytes. Screening was performed on scale samples collected from the interdigital or plantar area of cases including tinea pedis and other diseases, such as dyshidrotic eczema, palmoplantar pustulosis, pitted keratolysis and tylosis. The presence of dermatophytes in each scale sample was examined by direct microscopy and with the Dermatophyte Test Strip, as described previously. Briefly, a scale sample was added to the extraction solution in a test tube, mixed and left to stand for 5 min. The test strip was then added and a positive judgement was made after 5 min if a brown line was visible on the test strip (Fig. 1). The detection rate of tinea pedis was examined in samples from 162 patients (75 men, 87 women; mean SD age 61 9 16 8 years) (Table 1). Of the 58 samples that were positive in direct microscopy, 49 were also positive with the Dermatophyte Test Strip, giving a sensitivity of 84%. Of the 104 samples that were negative in direct microscopy, 80 were negative with the Dermatophyte Test Strip, giving a specificity of 77%. The positive predictive value (PPV) was 67%, the negative predictive value (NPV) was 90%, and the positive and negative concordance rate was 80%.

Factors Associated With Callus in Patients with Diabetes, Focused on Plantar Shear Stress During Gait

Background: The aim of this study is to identify whether plantar shear stress in neuropathic patients with diabetes with callus is increased compared with those without callus. Method: The differences in foot deformity, limited joint mobility, repetitive stress of walking, and ill-fitting shoes between patients with callus and those without callus were also determined. Subjects were recruited from the Diabetic Foot Outpatient Clinic. A newly developed in-shoe measurement system, which has flexible and thin insoles, enabled measurement of both plantar pressure and shear stress simultaneously when subjects walked as usual on a 10 m walkway. Results: It was found that plantar shear stress adjusted for weight during the push-off phase was increased by 1.32 times in patients with callus compared with those without callus (mean ± SD: 0.0500 ± 0.0160 vs 0.0380 ± 0.0144, P = .031). Moreover, hallux valgus deformity, reduction in dorsiflexion of the ankle joint and increase in plantar flexion were showed in feet with callus. Increased plantar shear stress may be caused by gait change that patients having callus push off with the metatarsal head instead of the toe as a result of foot deformity and limited joint mobility. Conclusions: It was found that plantar shear stress adjusted for weight during the push-off phase was increased in patients with callus compared with those without callus by using the newly developed measurement system. These results suggest that reduction of plantar shear stress during the push-off phase can prevent callus formation in neuropathic patients with diabetes.

Antifungal Effect of Non-Woven Textiles Containing Polyhexamethylene Biguanide with Sophorolipid: A Potential Method for Tinea Pedis Prevention

Tinea pedis is a preventable skin disease common in elderly or diabetic patients. Daily foot washing is effective for prevention, but can be difficult for many patients. Additionally, conventional methods cannot eliminate fungi within the stratum corneum, a common site for fungal invasion. This study investigates the antifungal effects, cytotoxicity, permeability, and efficacy of non-woven textiles containing polyhexamethylene biguanide (PHMB) mixed with sophorolipid. Permeability of PHMB with varying concentrations of sophorolipid was assessed via a cultured skin model. Stratum corneum PHMB concentration was quantified by polyvinylsulphuric acid potassium salt titration and cytotoxicity was assayed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. Antifungal effects were evaluated via a new cultured skin/Trichophyton mentagrophytes model, with varying PHMB exposure duration. Clinically-isolated Trichophyton were applied to the feet of four healthy volunteers and then immediately treated with the following methods: washing with soap, a non-woven textile with PHMB, the textile without PHMB, or without washing. Fungal colony forming units (CFUs) were evaluated after one of these treatments were performed. Sophorolipid with various concentrations significantly facilitated PHMB permeation into the stratum corneum, which was not in a dose-dependent manner. Significant PHMB antifungal effects were achieved at 30 min, with low cytotoxicity. Textiles containing PHMB significantly reduced CFU of fungi in healthy volunteers to levels comparable to soap washing. Our results indicate the utility of this product for tinea pedis prevention in clinical settings.

Screening for tinea unguium by thermography in older adults with subungual hyperkeratosis

The purpose of the present study was to assess the difference in foot temperature between tinea unguium‐positive older adults with subungual hyperkeratosis and tinea unguium‐negative older adults with subungual hyperkeratosis to develop a temperature‐based screening method for tinea unguium.