Pathophysiology of nocturnal scratching in childhood atopic dermatitis: the role of brain-derived neurotrophic factor and substance P.

BACKGROUND: Childhood atopic dermatitis (AD) is a distressing disease associated with pruritus and sleep disturbance. The pathophysiology of pruritus is complex and various neuropeptides may be involved. OBJECTIVE: To evaluate whether or not brain-derived neurotrophic factor (BDNF) and substance P are associated with disease severity, quality of life and nocturnal scratching in AD. METHODS: Patients with AD aged under 18 years were recruited. Disease severity was assessed with the SCORing Atopic Dermatitis (SCORAD) index, and quality of life with the Children's Dermatology Life Quality Index (CDLQI). Concentrations of plasma BDNF, substance P, AD-associated chemokines [cutaneous T-cell attracting cytokine (CTACK), thymus and activation regulated chemokine (TARC)], serum total IgE and eosinophil counts were measured in these patients. All children were instructed to wear the DigiTrac monitor on their dominant wrist while sleeping. The monitor was programmed to record limb motion between 22.00 and 08.00 h the following morning. RESULTS: Twenty-eight children with AD [mean (SD) age 11.1 (3.3) years] were recruited. The mean (SD) SCORAD was 48.1 (21.5) and CDLQI was 8.7 (5.4) in the patients with AD. Their mean (SD) plasma concentrations of BDNF, substance P, CTACK and TARC were 1798 (935), 94 (42), 1424 (719) and 824 (1000) pg mL(-1), respectively. BDNF was significantly correlated with SCORAD (r = 0.478, P = 0.010) and CDLQI (r = 0.522, P = 0.004), whereas substance P showed significant correlation only with CDLQI (r = 0.441, P = 0.019). BDNF and substance P were also significantly correlated with the average (r = 0.905, P < 0.001 and r = 0.925, P < 0.001) and frequency-specific (r = 0.826, P < 0.001 and r = 0.870, P < 0.001) nocturnal wrist activities measured by DigiTrac. However, there was no correlation between BDNF or substance P and the subjective symptoms of pruritus or sleep-loss scores as reported by the parents in the SCORAD. In contrast, serum total IgE levels showed significant correlations with the subjective symptoms of pruritus (r = 0.576, P = 0.001) and sleep loss (r = 0.419, P = 0.027). CONCLUSIONS: Serum levels of BDNF and substance P correlate with the clinical score and quality of life score in patients with AD. The strong correlations with nocturnal wrist movements suggest that they may be the pathogenic factors of the annoying symptoms of scratching.

Efficacy and tolerability of a Chinese herbal medicine concoction for treatment of atopic dermatitis: a randomized, double-blind, placebo-controlled study.

BACKGROUND: There has been considerable interest in traditional Chinese herbal medicine (TCHM) as a treatment for atopic dermatitis (AD). A twice-daily concoction of an ancestral formula containing five herbs has been found to be beneficial in an open study. OBJECTIVES: To assess the efficacy and tolerability of the concoction in children with AD. METHODS: Following a 2-week run-in period, children with long-standing moderate-to-severe AD were randomized to receive a 12-week treatment with twice-daily dosing of three capsules of either TCHM or placebo. The SCORing of Atopic Dermatitis (SCORAD) score, Children's Dermatology Life Quality Index (CDLQI), allergic rhinitis score, and requirement for topical corticosteroid and oral antihistamine were assessed before and at weeks 4, 8, 12 and 16 after treatment. Adverse events, tolerability, haematological and biochemical parameters were monitored during the study. RESULTS: Eighty-five children with AD were recruited. Over 12 weeks, the mean SCORAD score fell from 58.3 to 49.7 in the TCHM group (n = 42; P = 0.003) and from 56.9 to 46.9 in the placebo group (n = 43; P = 0.001). However, there was no significant difference in the scores at the corresponding time points between the two groups. The CDLQI in TCHM-treated patients was significantly improved compared with patients receiving placebo at the end of the 3-month treatment and 4 weeks after stopping therapy (P = 0.008 and 0.059, respectively). The total amount of topical corticosteroid used was also significantly reduced by one-third in the TCHM group (P = 0.024). No serious adverse effects were observed between the groups. CONCLUSIONS: The TCHM concoction is efficacious in improving quality of life and reducing topical corticosteroid use in children with moderate-to-severe AD. The formulation was palatable and well tolerated.

Which aeroallergens are associated with eczema severity?

We investigated if a correlation exists between aeroallergen sensitization and the severity of eczema. Data on aeroallergen response to skin-prick testing (SPT) and disease severity of children with eczema (n = 119) were evaluated. Atopy, as defined by at least one positive response to aeroallergen skin prick testing, was found in > 90% of eczema patients. House dust mite was the most commonly sensitized aeroallergen, followed by cat fur. Dermatophagoides pteronyssinus and Dermatophagoides farinae sensitization were associated with eczema severity (present in 67% of the mild and 97% of the severe group; P = 0.001). However, there was no association between eczema severity and higher strengths of SPT response (defined as SPT > 1+ to dust mites or dust). Atopy to moulds, Bermuda grass, cockroach, cat and dog was less prevalent and was not associated with eczema severity. It is sensible to advise parents on specific avoidance strategies only in severely affected children who have a definitive history of eczema exacerbation by specific aeroallergens and who are not responsive to conventional treatment.

Exhaled nitric oxide levels are not correlated with eczema severity in Chinese children with atopic dermatitis.

Asthma is a common atopic disease associated with atopic dermatitis (AD) and allergic rhinitis (AR). Exhaled nitric oxide level (eNO) has been found to be an interesting noninvasive marker of disease severity in children with asthma. However, it is uncertain if eNO may be confounded by any coexisting AD or AR. In this study, eNO in Chinese children with moderate-to-severe AD and no asthma symptoms (n = 53) was measured online by a chemiluminescence analyzer. Severity of AD was assessed using the objective SCORing-Atopic-Dermatitis score and coexisting allergic rhinitis with the Allergic-Rhinitis-Score (ARS). Patients with active symptoms of asthma or inhaled/intranasal corticosteroids were excluded. There was no difference in eNO between genders and no correlation between eNO and AD severity regardless of ARS or bronchial reactivity status. ENO appears to be a noninvasive marker whose level is independent of the two atopic diseases of AD and AR in children old enough to perform exhalation maneuver.

CDLQI, SCORAD and NESS: are they correlated?

BACKGROUND: Quality of life (QOL) and clinical severity scores are important parameters in the evaluation of distress experienced by children with atopic dermatitis (AD). The SCORing Atopic Dermatitis (SCOARD) is a widely used clinical score for assessing AD symptomatology over the preceding 3 days and the Nottingham Eczema Severity Score (NESS) is another score useful for AD symptoms over the preceding 12 months. OBJECTIVE: We evaluated if these parameters are correlated with QOL in children with AD. PATIENTS/METHODS: We assessed quality of life, clinical scores, total IgE and eosinophil count in peripheral blood in AD patients at our paediatric dermatology clinic over a 14-month period. RESULTS: Eighty AD patients (42 males and 38 females; mean [SD] age 11.7 [3.7] years) were recruited. The median (interquartile range, IQR) IgE, eosinophil counts and eosinophil percentage were 2988 (1069-7847) kIU/L; 0.6 (0.4-0.9) x 10(-9)/L; and 9 (6-12)%, respectively. Quality of life as measured with CDLQI (The Children's Dermatology Life Quality Index) generally did not correlate well with both the acute and chronic AD severity scores (objective SCORAD and total CDQLI, rho = 0.17, p > 0.05; total NESS and total CDQLI, rho = 0.29, p < 0.05). Factor analysis further confirmed that the objective indicators (serum total IgE, eosinophil count and objective SCORAD), self-reported scores (NESS and subjective SCORAD) and CDLQI were separate dimensions in the assessment of AD in children. CONCLUSION: Quality of life, disease severity scores and laboratory atopic markers represent different domains in AD assessment. They do not necessarily correlate well with each other and all three aspects must be individually evaluated to assess the well-being of these patients.

Nocturnal wrist movements are correlated with objective clinical scores and plasma chemokine levels in children with atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is a distressing disease associated with pruritus and sleep disturbance. Scratching due to pruritus is an important mechanism in the exacerbation of AD but is difficult to document in the home environment. OBJECTIVES: To evaluate whether nocturnal wrist activities, defined as average acceleration in the early hours of sleep, were correlated with components of the SCORing Atopic Dermatitis (SCORAD) index and various AD-associated chemokine markers. METHODS: Patients with AD aged under 18 years were recruited and the severity of eczema was assessed with the SCORAD index. Concentrations of plasma AD-associated chemokines [cutaneous T-cell attracting cytokine (CTACK); macrophage-derived chemokine (MDC); thymus and activation regulated chemokine (TARC)], interleukin (IL)-18, serum total IgE, and eosinophil counts were measured in these patients. Healthy children with noninflammatory and nonitchy skin conditions as well as healthy children of staff volunteers were recruited as controls. All children were instructed to wear the DigiTrac monitor on their dominant wrist before sleeping. The monitor was programmed to record limb motion between 22.00 and 08.00 h the following morning. RESULTS: Twenty-four Chinese children with AD (mean +/- SD age 12.6 +/- 3.7 years) and 15 normal children (mean +/- SD age 11.9 +/- 3.4 years) were recruited. The median (interquartile range) SCORAD was 54.8 (32.8-70.2). Plasma concentrations in pg mL(-1) of CTACK, MDC, TARC and IL-18 in the patients were 105 (92-172), 1648 (973-4214), 258 (100-850) and 415 (304-539), respectively. When compared with controls, most wrist activities occurred at frequencies between 1 and 3 Hz. These activities were most consistent over the first 3 h of sleeping and correlated significantly with disease severity, extent, intensity, and AD-associated chemokine markers CTACK, MDC and TARC. However, there was no significant correlation between wrist activities and the subjective symptom of pruritus or sleep loss. CONCLUSIONS: This is the first study to demonstrate that wrist activities, nonintrusively measured by the DigiTrac monitor at home, are closely correlated with the objective clinical scores and levels of peripheral blood chemokine markers for AD but not with the reported symptoms of pruritus or sleep loss. We propose that wrist activities between 1 and 3 Hz for the first 3 h are a good indicator of AD severity in children and should substitute for the pruritus and sleep-loss components of the SCORAD.

Dietary restriction and supplementation in children with atopic eczema.

Issues on empirical dietary restriction or supplementation are important but inadequately studied in children with atopic eczema (AE). The dietary habits of children with AE followed at a paediatric dermatology clinic (n = 179) were compared with those without eczema (n = 78). The mothers of 53% of the patients with or without eczema did not breastfeed their children. Common food items avoided by parents whose children have moderate-to-severe AE included fish or seafood [64% vs. 32% of controls, odds ratio (OR) 3.84, 95% CI 2.12-6.95], beef (42% vs. 17%; OR = 3.57, 95% CI 1.79-7.11), eggs (34% vs. 14%; OR = 3.05, 95% CI 1.46-6.34) and cows' milk (18% vs. 4%; OR = 5.56, 95% CI 1.61-19.12); whereas their avoidance was less frequent in children with noneczematous diseases. The avoidance of these foods were often based on belief, but 66% of all AE patients who had avoided any of the above foods reported previous experience of eczema exacerbation by these items. Patients with moderate-to-severe AE were more likely to have consumed 'bird's nest' soup and traditional Chinese medicines. It is important to evaluate whether the AE patients are genuinely 'allergic' to some of these food items. Management is suboptimal if children with food allergy and severe disease continue to consume the culprit food. Conversely, avoidance of common foods in children without food allergy could result in food faddism or malnutrition.

Clinical features associated with nasal Staphylococcus aureus colonisation in Chinese children with moderate-to-severe atopic dermatitis.

INTRODUCTION: Staphylococcus aureus colonisation/infection is common in children with atopic dermatitis (AD). MATERIALS AND METHODS: We evaluated the nasal and body swabs of Chinese children with moderate-to-severe AD as assessed using SCORing-Atopic-Dermatitis (SCORAD) score. Swabs were taken from the right nostril, 5 flexural sites (anterior neck, antecubital fossae and popliteal fossae) and the skin area most severely affected (with oozing/crusting) for bacteriologic culture. RESULTS: Fifty-five children (30 males and 25 females) were evaluated. Moderate-to-heavy growth of S. aureus was present in 12 (22%) of the nasal swabs, and in 1 or more flexural swabs of 32 (58%) of these children. Only 7 (35%) out of the 20 patients who had swabs taken from the worst skin area had moderate-to-heavy growth of S. aureus. Significant nasal S. aureus colonisation was associated with higher total (P=0.029) and objective SCORAD scores (P=0.040), more extensive disease (P=0.025), the presence of oozing or crusting (P=0.023) and higher eosinophil counts (P=0.038). All specimens of methicillin-sensitive S. aureus were sensitive to cloxacillin and 71% to erythromycin. Methicillin-resistant S. aureus (MRSA), sensitive to vancomycin, was only isolated in 1 patient. CONCLUSIONS: In this study, S. aureus is a principal pathogen. Cloxacillin and first-generation cephalosporins have a favourable sensitivity profile even in children with moderate and severe atopic dermatitis. The anterior nares are an important harbour for S. aureus and significant nasal S. aureus colonisation was clinically associated with more extensive lesions and the presence of oozing or crusting.