Assessment of the elicitation response in subjects weakly sensitized to p-phenylenediamine.

BACKGROUND: A 30-min application of a hair dye product containing 2% p-phenylenediamine (PPD) to subjects diagnostically graded +, showed that 12 of 18 reacted; eight of 18 with a true + and four of 18 with a doubtful (?+) response, whereas six of 18 did not react at all. In vitro skin-binding experiments showed that for diagnostic patch test conditions the measured exposure level (MEL) is more than 10-fold higher than the MEL for hair dyeing conditions. OBJECTIVE: To further analyse the limited elicitation response of the diagnostically + graded subjects to a PPD hair dye product, under standardized test conditions mimicking product usage, by varying exposure time and dose. METHODS: A hair dye model formulation containing 2% PPD, applied for 30, 45 and 60 min and a diagnostic PPD TRUE test(®) were applied to assess elicitation responses to increasing PPD exposure levels. Grading was performed according to International Contact Dermatitis Research Group guidelines. RESULTS: Six subjects were available for this follow-up study. One of six subjects responded with a + elicitation response to the hair dye model applied for 60 min. Four of the five remaining subjects elicited a + response to the PPD TRUE test(®) applied subsequently, while one of five responded doubtfully. CONCLUSIONS: Increasing the PPD exposure time twofold--resulting in a 5-6% increase of sensitivity of this hair dye model test--or further extending the exposure time 48-fold, was found sufficient to increase the MEL above the thresholds needed to elicit individuals with a + diagnostic PPD patch test who did not react to typical hair dye use conditions with a MEL of about 6·8 µg cm⁻². This analysis confirms that consideration of the MEL is a useful tool to better characterize thresholds of elicitation than consideration of the applied dose alone.

Costs and cost-effectiveness analysis of treatment in children with eczema by nurse practitioner vs. dermatologist: results of a randomized, controlled trial and a review of international costs.

BACKGROUND: In a randomized, controlled trial (RCT) on childhood eczema we reported that substituting nurse practitioners (NPs) for dermatologists resulted in similar outcomes of eczema severity and in the quality of life, and higher patient satisfaction. OBJECTIVES: To determine costs and cost-effectiveness of care provided by NPs vs. dermatologists and to compare our results with those in studies from other countries. METHODS: We estimated the healthcare costs, family costs and the costs in other sectors alongside the RCT. All the costs were linked to quality of life [Infants' Dermatitis Quality of Life Index (IDQOL), Children's Dermatology Life Quality Index (CDLQI)] and to patient satisfaction (Client Satisfaction Questionnaire-8) to determine the incremental cost-effectiveness ratio (ICER). We also examined all the reported studies on the costs of childhood eczema. RESULTS: The mean annual healthcare costs, family costs and costs in other sectors were €658, €302 and €21, respectively, in the NP group and €801, €608 and €0·93, respectively, in the dermatologist group. The ICER in the NP group compared with the dermatologist group indicated €925 and €751 savings per one point less improvement in IDQOL and CDLQI, respectively, and €251 savings per one point more satisfaction in the NP group at 12 months. The mean annual healthcare costs and family costs varied considerably in the six identified studies. CONCLUSIONS: Substituting NPs for dermatologists is both cost-saving and cost-effective. The treatment of choice is that provided by the NPs as it is similarly effective to treatment provided by a dermatologist with a higher parent satisfaction. International comparisons are difficult because the types of costs determined, the units and unit prices, and eczema severity all differ between studies.

Comparators, study duration, outcome measures and sponsorship in therapeutic trials of psoriasis: update of the EDEN Psoriasis Survey 2001-2006.

BACKGROUND: Several new therapeutic options for psoriasis have been tested in clinical trials in recent years. Choice of comparator, study duration and outcome measures are critical for interpreting application of trial results to clinical practice. OBJECTIVES: We examined whether these trial aspects have changed substantially in recent years in comparison with the past. METHODS: A systematic search and evaluation of all randomized controlled trials (RCTs) for psoriasis published from January 2001 up to December 2006 in 14 leading medical and dermatological journals, compared with those published from 1977 to 2000. RESULTS: There were 140 RCTs of psoriasis in the period 2001-2006 and 249 in the period 1977-2000. The proportion of placebo-controlled studies increased from 44.6% to 69.3%. The median study duration increased from 7 weeks to 12 weeks. The proportion of studies adopting the Psoriasis Area and Severity Index score as an outcome increased from 30.6% to 57.7%, while the number of studies incorporating a quality of life measure increased from only one (0.4%) to 12 studies (7.7%). The proportion of studies sponsored by pharmaceutical companies increased from 61.0% to 73.7%. CONCLUSIONS: Despite the increased number of new options, the number of head-to-head comparative trials has decreased and most trials focus on short-term effects, probably reflecting the increased influence of industrial sponsorship on the research agenda.

Assessment of severity of hand eczema: discrepancies between patient- and physician-rated scores.

BACKGROUND: In clinical practice or trials on hand eczema the severity of this disease can be 'measured' in different ways: by means of a physician-rated clinical severity score, a patient-rated clinical severity score or by an indicator of the burden of disease. We assume that the patient-rated severity score corresponds more with the (change in) burden of disease than with the physician-rated severity score. OBJECTIVES: To demonstrate how physicians and patients differ in their assessment of the severity of hand eczema as seen in a physician-rated severity score, patient-rated severity score and a burden of disease questionnaire. METHODS: We used data from an open-label randomized controlled trial which was set up in two university hospital dermatology departments in the Netherlands, specializing in hand eczema. One hundred and fifty-eight patients with moderate to severe chronic hand eczema were included. The main outcome measures were the physician-rated severity score, based on five visible aspects of hand eczema (desquamation, erythema, vesicles, infiltration, fissures), the patient-rated severity score (a self-rating scale), a burden of disease questionnaire (the Dermatology Life Quality Index, DLQI) and the correlations between these parameters, both at inclusion and over time. RESULTS: Only desquamation and infiltration were significantly correlated with patient-rated severity score. Patient-rated severity score correlated with seven of 10 DLQI items, but it did not correlate with the items regarding influence on clothes worn, impairment of sporting activities, and problems associated with treatment of the skin. The majority of patients showed improvement in all parameters after treatment. However, the improvement in patient-rated severity score was not clearly correlated with changes in physician-rated severity score. Except for DLQI item 1 (itch, soreness, pain, stinging), none of the changes in burden of disease was correlated with changes in patient-rated severity score. For each DLQI item, change over time correlated weakly with decreases in several, but not all, components of the physician-rated severity score. CONCLUSIONS: Disease severity can be expressed by different scores; these scores are not clearly correlated, and measure different aspects. Patient satisfaction is not guaranteed when treatment is focused solely on the visible aspects of hand eczema. Instead, burden of disease has a greater impact.

The epidemiology of occupational contact dermatitis.

Occupational contact dermatitis (OCD) ranks first of all occupational diseases in many countries. The incidence rate is believed to be around 0.5-1.9 cases per 1000 full-time workers per year. Epidemiological studies play an important role in observing disease trends, analysing risk factors, and monitoring the effect of preventive measures. In this review article the lack of truly epidemiologic data on OCD and the difficulties of those studies are illustrated. The following issues are highlighted: case ascertainment and bias, the distribution of allergic and irritant contact dermatitis in the working population, the interrelationship between exogenous (allergens, irritants) and endogenous factors, the prognosis, the social and economic impact, and the need for intervention studies.

[Skin diseases and working disability in the Netherlands. II. Catamnestic study in 3 groups of patients with occupational contact eczema]. / Hautkrankheiten und Arbeitsunfähigkeit in den Niederlanden II. Eine katamnestische Untersuchung bei drei Gruppen von Patienten mit einem Berufskontaktekzem.

A follow-up study was performed of the medical and social condition of 164 patients with an occupational allergic contact dermatitis. A change of work did not always lead to an improvement of the dermatitis. A number of patients improved without changing their job. It is suggested that a change of occupation can only be advised to these patients if the causal allergen can be avoided completely by doing so and only by doing so; at the same time one must reckon with other aetiologic factors and the social situation after change of work. Moreover it is pointed out that patients who changed their occupation did hardly use the possibilities, created by the Dutch law, to obtain expert advice or to be retrained for another job at the expense of the community.