Objective assessment of vitiligo with a computerised digital imaging analysis system.

An objective tool to quantify treatment response in vitiligo is currently lacking. This study aimed to objectively evaluate the treatment response in vitiligo by using a computerised digital imaging analysis system (C-DIAS) and to compare it with the physician's global assessment (PGA). Tacrolimus ointment 0.1% (Protopic; Astellas Pharma Tech,Toyama, Japan) was applied twice daily on selected lesions which were photographed every 6 weeks for 24 weeks. The primary efficacy end-point was the mean percentage of repigmentation (MPR), as assessed by the digital method (MPR-C-DIAS) or by the PGA. The response was categorised into none (0%), mild (1-25%), moderate (26-50%), good (51-75%) and excellent (76-100%). MPR-C-DIAS: Out of 56 patients, 44 (79%) responded. Overall, the response was mild in 22 (39%), moderate in 21(40%) and good in one (2%) patient(s). A total of 39 (70%) patients responded as measured by PGA. The repigmentation was mild in 27(48%), moderate in 10 (18%) and good to excellent in two (4%) patients. The κ test of consistency was 0.17 (P = 0.053), which shows poor agreement between the two assessment methods, although this is not statistically significant. The C-DIAS can be used to perform an objective analysis of repigmentation or depigmentation in vitiligo skin lesions in response to treatment.

3D surface roughness measurement for scaliness scoring of psoriasis lesions.

Psoriasis is an incurable skin disorder affecting 2-3% of the world population. The scaliness of psoriasis is a key assessment parameter of the Psoriasis Area and Severity Index (PASI). Dermatologists typically use visual and tactile senses in PASI scaliness assessment. However, the assessment can be subjective resulting in inter- and intra-rater variability in the scores. This paper proposes an assessment method that incorporates 3D surface roughness with standard clustering techniques to objectively determine the PASI scaliness score for psoriasis lesions. A surface roughness algorithm using structured light projection has been applied to 1999 3D psoriasis lesion surfaces. The algorithm has been validated with an accuracy of 94.12%. Clustering algorithms were used to classify the surface roughness measured using the proposed assessment method for PASI scaliness scoring. The reliability of the developed PASI scaliness algorithm was high with kappa coefficients>0.84 (almost perfect agreement).

Transepidermal water loss in erythrodermic patients of various aetiologies.

BACKGROUND/PURPOSE: Despite its severity not much work has been done to explore the barrier function in patients with erythroderma. This study compares TEWL between skin of healthy subjects and erythrodermic patients of various aetiologies and at different sites. We also assess TEWL between patients with acute and chronic erythroderma. METHODS: Twenty-five erythrodermic patients and 26 age, race and sex-matched healthy controls were recruited. TEWL measurements were performed at five sites; right cheek, left volar forearm, abdomen, upper back and right calf using Tewameter TM 210. RESULTS: TEWL in erythrodermic patients were significantly higher than healthy individuals at all the sites (P < 0.001). There were significant differences in TEWL between different anatomical sites in controls (P < 0.001) but not in patients. The highest TEWL for the patient and control groups were that of the abdomen and the right cheek respectively. Acute erythrodermic patients (n = 9) seemed to have a higher TEWL than chronic erythrodermic patients (n = 16) although the differences were not statistically significant. There was no significant difference in TEWL among erythrodermic patients of various aetiologies. CONCLUSION: Erythrodermic skin regardless of aetiology has much higher TEWL compared to normal skin. Differences in TEWL among various anatomical sites observed in normal skin were not seen in erythroderma.

Body surface area measurement and soft clustering for PASI area assessment.

Psoriasis is a common skin disorder with a prevalence of 0.6 - 4.8% around the world. The most common is plaques psoriasis and it appears as red scaling plaques. Psoriasis is incurable but treatable in a long term treatment. Although PASI (Psoriasis Area and Severity Index) scoring is recognised as gold standard for psoriasis assessment, this method is still influenced by inter and intra-rater variation. An imaging and analysis system called α-PASI is developed to perform PASI scoring objectively. Percentage of lesion area to the body surface area is one of PASI parameter. In this paper, enhanced imaging methods are developed to improve the determination of body surface area (BSA) and lesion area. BSA determination method has been validated on medical mannequin. BSA accuracies obtained at four body regions are 97.80% (lower limb), 92.41% (trunk), 87.72% (upper limb), and 83.82% (head). By applying fuzzy c-means clustering algorithm, the membership functions of lesions area for PASI area scoring have been determined. Performance of scoring result has been tested with double assessment by α-PASI area algorithm on body region images from 46 patients. Kappa coefficients for α-PASI system are greater than or equal to 0.72 for all body regions (Head - 0.76, Upper limb - 0.81, Trunk - 0.85, Lower limb - 0.72). The overall kappa coefficient for the α-PASI area is 0.80 that can be categorised as substantial agreement. This shows that the α-PASI area system has a high reliability and can be used in psoriasis area assessment.

Association of HLA-B*1502 allele with carbamazepine-induced toxic epidermal necrolysis and Stevens-Johnson syndrome in the multi-ethnic Malaysian population.

BACKGROUND: Carbamazepine (CBZ), a frequently used anticonvulsant drug, is one of the most common causes of life-threatening cutaneous adverse drug reactions such as toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS). Recent studies have revealed a strong association between HLA-B*1502 and CBZ-induced TEN/SJS in the Taiwan Han Chinese population. OBJECTIVES: This study is aimed to investigate the association between human leucocyte antigens (HLA) and CBZ-induced TEN/SJS in the multi-ethnic Malaysian population. METHODS: A sample of 21 unrelated patients with CBZ-induced TEN/SJS and 300 race-matched, healthy controls were genotyped for HLA-A, -B and -DR using polymerase chain reaction (PCR). Allele frequencies were compared. RESULTS: HLA-B*1502 was present in 75.0% (12/16) of Malay patients with CBZ-induced TEN/SJS but in only 15.7% (47/300) of normal controls (odds ratio 16.15, 95% confidence interval 4.57-62.4; corrected P-value = 7.87 × 10(-6) ), which suggests a strong association between HLA and CBZ-induced TEN/SJS. Additionally, HLA-B*1502 was found in all three Chinese and two Indian patients. Existing data show that frequencies of the HLA-B*1502 allele are generally much higher in Asian populations than in White European populations, which explains the higher incidences of SJS and TEN in Asian countries. CONCLUSIONS: HLA-B*1502 is strongly associated with CBZ-induced TEN/SJS in the Malay population in Malaysia, as has been seen in Han Chinese in Taiwan. This indicates that the genetic association apparent in the incidence of CBZ-induced TEN/SJS is linked with the presence of HLA-B*1502, irrespective of racial origin. Screening of patients for this genetic marker can help to prevent the occurrence of TEN/SJS.

A study on the knowledge, attitudes and practices of Southeast Asian dermatologists in the management of atopic dermatitis.

INTRODUCTION: This study evaluated the knowledge, attitudes and practices of Southeast Asian dermatologists in the management of atopic dermatitis (AD). MATERIALS AND METHODS: A questionnaire survey of 255 dermatologists in Indonesia, Malaysia, the Philippines, Singapore, Thailand and Vietnam. RESULTS: Familiarity with diagnostic criteria varied considerably. The usage of moisturisers by the respondents from Vietnam and Indonesia was significantly less frequent than the other countries. Most respondents (91% to 100%) used topical corticosteroids in children with mild-to-moderately severe dermatitis. Some respondents in the Philippines (17% to 19%) and Vietnam (11% to 25%) only used topical corticosteroids for severe disease. For infected eczema, most respondents would prescribe systemic antibiotics for mild-to-moderate infection. A minority in the Philippines (14%) and Vietnam (11%) did so only for severe infection. The top 4 systemic antibiotics prescribed most frequently were: erythromycin, cloxacillin, cephalosporin and amoxicillin/clavulanic acid. In Indonesia, a large proportion of the respondents (47%) prescribed amoxicillin most frequently. The majority of respondents (60% to 100%) prescribed both sedating and non-sedating oral antihistamines. Most respondents used oral corticosteroids to treat severe AD. Some in Malaysia, Singapore and Vietnam used cyclosporin (7% to 58%), azathioprine (5% to 31%) and methotrexate (5% to 14%). With the exception of those in Singapore, the majority of respondents (71% to 97%) did not use phototherapy. CONCLUSION: Familiarity with diagnostic criteria, the early and judicious use of moisturisers and topical corticosteroids, as well as the treatment of Staphylococcus aureus superinfection with penicillinase-stable antibiotics should be emphasised in this region.

Drug-induced urticaria and angioedema: pathomechanisms and frequencies in a developing country and in developed countries.

A careful drug history should be obtained from all patients with acute or chronic urticaria/angioedema, especially in the elderly. Although strictly comparable data are lacking, drug-induced urticaria appears to be more common in developed countries than in Malaysia, at least in a Hospital setting. Culprit drugs include antibiotics, analgesics and contrast media. Pseudoallergic drug-induced urticaria mimicks true allergic urticaria, but without an evident immunological basis, and is at least as common as the allergic type. In Malaysia, and in many other countries compulsory, ingredient labelling of 'traditional' medicines would do much to reduce the frequency of drug-induced urticaria.