Comparison of epidermal hydration and skin surface lipids in healthy individuals and in patients with atopic dermatitis

BACKGROUND: The water content of the stratum corneum and skin surface lipids are important factors in the appearance and function of the skin. A disruption of the balance between the two may lead to the clinical manifestation of dryness of skin in patients with atopic dermatitis. OBJECTIVE: The aim of our study was to examine the so-called dry skin of patients with atopic dermatitis using objective parameters. We compared the epidermal hydration and the skin surface lipids, the so-called hydro-lipid film, of the clinically unaffected skin of patients suffering from atopic dermatitis with that of healthy subjects. METHODS: A total of 48 patients of either gender were included in this retrospective case-control study. We used the Corneometer CM 820 (Courage+Khazaka Electronic GmbH, Cologne, Germany) and the Sebumeter SM 810 (Courage+Khazaka Electronic GmbH) as noninvasive measuring methods. RESULTS: The results showed marked decreases in the atopic dermatitis group for both the Corneometer and Sebumeter measuring methods. CONCLUSION: Our results show that the dry skin of patients with atopic dermatitis, as previously shown, is due not only to a decrease in skin moisture but also to a reduction of skin lipids. This finding gives rise to a new understanding of the condition, and therefore one should always speak of a hydro-lipid film.     

Comparative study of staphylococci from the skin of atopic dermatitis patients and from healthy subjects

BACKGROUND: Bacterial infections occur frequently on the skin of atopic dermatitis (AD) patients. The objectives of this study were to evaluate the microbiology of the skin of AD patients for staphylococci, the frequency and density of each species, and their susceptibility to antimicrobial drugs. METHODS: To study the staphylococci present on the skin of 21 AD outpatients and of 12 healthy subjects (HS), cutaneous organisms were obtained using the contact-plate method. RESULTS: Staphylococcus aureus was isolated in 85.7% of AD patients (mild type, 77.8%; moderate type, 87.8%; and severe type, 100%) and in 25% of HS, while Staphylococcus epidermidis was isolated in 83.3% of HS and in 38.1% of AD patients. Among the coagulase-negative staphylococci (CNS) identified, S. epidermidis was the common type and several other CNS were detected in both AD patients and HS. As the eruption grade of dermatitic skin became more severe, the average density of S. aureus increased (severe, 2.68 +/- 0.86; moderate, 2.49 +/- 0.48; mild, 2.28 +/- 0.44). A reversed tendency was seen in S. epidermidis (severe, 1.80; moderate, 1.90; mild, 2.10). Among nine antimicrobial drugs tested against S. aureus, S. epidermidis, and some other types of CNS isolates, vancomycin (VCM) and minocycline (MINO) were the most active, gentamycin (GM) was the less active, and ampicillin (ABPC) was the least active. CONCLUSIONS: The skin of AD patients was more frequently colonized with S. aureus than that of normal controls. As the severity of the AD lesions increased, the numbers of S. aureus isolated increased. The skin of HS was more colonized with S. epidermidis. Other species of CNS were isolated from several cases of AD patients and HS. In addition, S. aureus, S. epidermidis, and the other CNS showed poor susceptibility to some of the tested antimicrobial drugs.     

Premenstrual deterioration of skin symptoms in female patients with atopic dermatitis

BACKGROUND: Although it has been recognized that women with atopic dermatitis often show menstrual-cycle-associated skin deterioration, information about this subject is meager. OBJECTIVE: To clarify the clinical features of the monthly worsening of atopic dermatitis. METHODS: A total of 286 Japanese women with atopic dermatitis were interviewed to see whether the menstrual cycle had any influence upon their skin lesions, and whether they had symptoms of premenstrual syndrome. Patients suffering from monthly skin deterioration were then observed during and after the monthly worsening. RESULTS: Of the 286 patients interviewed, 134 (47%) had monthly skin deterioration, most of which occurred in the premenstrual week. There was individual difference in severity of the monthly skin worsening. All patients with the premenstrual skin aggravation had symptoms of premenstrual syndrome. CONCLUSIONS: Premenstrual worsening of skin lesions occurs in approximately half of women with atopic dermatitis. The premenstrual skin deterioration is related to the premenstrual syndrome.     

Contact allergy to Dermatophagoides in atopic dermatitis patients and healthy subjects

To compare different house-dust-mite-derived allergenic materials and to correlate the presence of IgE LO Dermatophagoides with patch test results, 313 atopic dermatitis (AD) patients and 100 healthy volunteers (HV) underwent patch tests with: Dermatophagoides Pteronyssimus (DPT) lyophilized purified alpha fraction in buffered saline/glycerol 50% and or in petrolatum (Bayropharm); 540% DPT and 50% Dermatophagoides farinae (DF) whole bodies in petrolatum and petrolatum oil (Allergopharma-Bracco); DPT and DF whole bodies in petrolatum and petrolatum oil (Lofarma). We found 39% positive reactions among AD subjects and 13% in HV The presence of serum-specific IgE did not influence the patch test results. with of AD patch-lest-positive patients and 5 of 13 HV respectively, showed a positive prick less and or RAST lo Dermatophagoides. Similar sensitization rates were observed with the allergenic material from Bayropharm (54% positivities) and Allergopharma-Bracco (51% positivities), whereas the preparations from Lofarma gave a 20% response rate.     

Stratum corneum hydration and skin surface pH in patients with atopic dermatitis

Atopic dermatitis (AD) is a chronically relapsing skin disease with genetic predisposition, which occurs most frequently in preschool children. It is considered that dryness and pruritus, which are always present in AD, are in correlation with degradation of the skin barrier function. Measurement of hydration and pH value of the stratum corneum is one of the noninvasive methods for evaluation of skin barrier function. The aim of the study was to assess skin barrier function by measuring stratum corneum hydration and skin surface pH of the skin with lesions, perilesional skin and uninvolved skin in AD patients, and skin in a healthy control group. Forty-two patients were included in the study: 21 young and adult AD patients and 21 age-matched healthy controls. Capacitance, which is correlated with hydration of stratum corneum and skin surface pH were measured on the forearm in the above areas by SM810/CM820/pH900 combined units (Courage AND Khazaka, Germany). The mean value of water capacitance measured in AD patients was 44.1 ± 11.6 AU (arbitrary units) on the lesions, 60.2 ± 12.4 AU on perilesional skin and 67.2 ± 8.8 AU on uninvolved skin. In healthy controls, the mean value was 74.1 ± 9.2 AU. The mean pH value measured in AD patients was 6.13 ± 0.52 on the lesions, 5.80 ± 0.41 on perilesional skin, and 5.54 ± 0.49 on uninvolved skin. In control group, the mean pH of the skin surface was 5.24 ± 0.40. The values of both parameters measured on lesional skin were significantly different (capacitance decreased and pH increased) from the values recorded on perilesional skin and uninvolved skin. The same held for the relation between perilesional and uninvolved skin. According to study results, the uninvolved skin of AD patients had significantly worse values of the measured parameters as compared with control group. The results of this study suggested the skin barrier function to be degraded in AD patients, which is specifically expressed in lesional skin.     

Dermatology life quality index scores in children with vitiligo: comparison with atopic dermatitis and healthy control subjects

Vitiligo and atopic dermatitis (AD) are two major cutaneous diseases that affect quality of life (QoL) by causing functional and psychosocial disorders. Our objective was to calculate Children’s Dermatology Life Quality Index (CDLQI) scores in children with vitiligo and to compare these values with those in AD patients and healthy control subjects. The CDLQI was completed for 50 vitiligo and 50 AD patients presenting at the dermatology polyclinic, as well as for 50 age‐ and sex‐matched healthy controls. All subgroups in the vitiligo patient group had significantly higher total CDLQI scores than healthy controls. Vitiligo patients were found to have increased scores on all parameters, except itch, clothes/shoes, and sleep, compared with the AD patient group. Scores on itch and sleep were significantly higher in the AD group than in the vitiligo patients. Quality of life in children with vitiligo is substantially lower than in children with AD. This decline in QoL is critical in the psychosocial development of the former group.     

Neuropeptides in the skin of patients with atopic dermatitis

There is increasing evidence that neuropeptides may be involved in the pathogenesis of atopic dermatitis (AD). This study examines whether neuropeptide distribution in the skin of patients with AD differs from normal controls. The distribution and density of several neuro-peptides were examined in lesional and non-lesional skin of AD patients (n= 5) and in normal controls (n= 4) using indirect immunofluorescence and image analysis. Cholinergic innervation was studied using cholinesterase histochemistry. Staining with the general neuronal marker protein gene product 9·5 showed a subepidermal network of nerves with fibres penetrating the epidermis, and nerves around blood vessels, sweat glands and hair follicles. Image analysis of nerves around sweat glands showed a significantly higher nerve density in non-lesional compared with both normal controls and lesional skin (P < 0·05); lesional compared with control skin showed no significant difference. In the epidermis the density of nerves was not significantly greater in non-lesional compared with lesional skin and controls. Calcitonin gene-related peptide immunoreactivity was similar in all subjects except in three of the AD patients, where more nerves appeared to penetrate the epidermis. Substance P immunoreactivity in the papillary dermis was seen in all AD patients hut no controls. Vasoactive intestinal polypeptide and neuropeptide Y staining were similar in all groups. Acetyleholinesterase-positive nerves were found around sweat glands in all subjects, the staining being greatest in non-lesional and least in lesional skin. Occasional nerves were seen in the papillary dermis in lesional skin of two out of the four patients. We have demonstrated quantitative differences in nerve growth in clinically normal skin of AD patients, and altered cutaneous neuropeptide expression in these patients which may contribute to the pathogenesis of AD.     

N-acetyltransferase 2 acetylation polymorphism: prevalence of slow acetylators does not differ between atopic dermatitis patients and healthy subjects

The genetic polymorphism of human N-acetyltransferase 2 (NAT2) divides the human population into groups with rapid, intermediate and slow acetylator status. Slow acetylator status has been considered a predisposing factor for allergic diseases, lupus erythematosus, toxic epidermal necrolysis or Stevens-Johnson syndrome. The aim of this study was to investigate whether Caucasian patients suffering from atopic dermatitis differed from healthy individuals with regard to the genotype and phenotype of NAT2. Twenty unrelated healthy Caucasian volunteers (9 females and 11 males, aged from 22 to 59 years) and twenty unrelated Caucasian patients suffering from atopic dermatitis (9 females and 11 males, aged between 20 and 54 years) participated in this study. For each one, the NAT2 genotype was determined by polymerase chain reaction with DNA extracted from peripheral blood, using specific primers for the wild-type allele (wt) and the 3 most frequent mutated alleles of NAT2 (C481-->T, G590-->A and G857-->A). The NAT2 phenotype was evaluated with dapsone as a test substrate using high-pressure liquid chromatography. Statistical analysis was performed using the chi(2) test. Phenotype and genotype were distributed as follows: (1) of the healthy subjects, 60% were rapid acetylators (RA) and 40% were slow acetylators (SA); 10% of the RA and 15% of the SA were homozygous, 50% of the RA and 25% of the SA were heterozygous; (2) of the patients, 55% were RA, 40% were SA and 5% were intermediate acetylators (IA); 10% of the RA and 10% of the SA were homozygous, 45% of the RA and 35% of the SA were heterozygous. No significant statistical difference was found between the two groups for genotypes (p = 0.75) or phenotypes (p = 0.60). The phenotyping and genotyping results of healthy subjects were comparable to those found in previous studies. The absence of a significant statistical difference between healthy subjects and atopic dermatitis patients is in contrast to the results of previous studies. Some authors considered that allergic patients are mostly SAs. This could be explained by the fact that we only considered patients suffering from atopic dermatitis whereas, in other studies, patients suffered from different (one or several associated) allergic diseases. NAT2 polymorphism does not differ between patients suffering from atopic dermatitis and healthy subjects. The importance attributed to the SA status, which was previously considered a predisposing factor for allergic diseases such as atopic dermatitis, should be reviewed.     

Prognostic factor of adult patients with atopic dermatitis

The increased prevalence of atopic dermatitis (AD) in adults in recent decades suggests that dermatologists may be expected to estimate the prognosis of adult patients with AD when they visit as new patients. We therefore evaluated the change in the extent of involvement and analyzed the factors that contribute to the prognosis of adult AD. A retrospective chart review was performed for 65 adults patients (median age at first visit, 25 years) with AD who had been followed monthly for over 10 years. The median area of involvement at first visit was 19%. The area of the eruptions and peripheral eosinophil counts decreased significantly in the fifth and 10th years with standard treatment. The values of immunoglobulin (Ig)E were also reduced after 10 years. Patients with high values of serum total IgE and peripheral eosinophil count, and long duration of AD had wide areas of eruptions 10 years after the first visit. Total IgE had the highest correlation with area of involvement after 10 years. Although the prognosis of adult AD is not poor, patients with high IgE values are expected to have ongoing eczema with wide distribution after 10 years of follow up.     

Occurrence of patchy parakeratosis in normal-appearing skin in patients with active atopic dermatitis and in patients with healed atopic dermatitis: a cause of impaired barrier function of the atopic skin

It remains unclear whether an impaired barrier function often seen in areas of normal-appearing skin in patients with active atopic dermatitis (AD) is primary event in nature or secondary to subclinical eczematous change. We then attempted to evaluate the barrier function of normal-appearing skin in both active and healed AD patients, and as well as see whether a subclinical eczematous change exists or not in the normal-appearing skin using a non-invasive method. Transepidermal water loss (TEWL) measurement and exfoliative cytology method for corneal layer were applied in 153 AD patients who have active skin lesions and 29 individuals with completely healed AD for at least 5 years and 40 normal individuals. The TEWL of normal-appearing skin in severe, moderate and mild AD cases was 10.5+/-2.9, 8.3+/-2.4 and 7.3+/-2.1 g/m2 per h, respectively. The TEWL values in severe and moderate cases were significantly higher than the normal controls (6.2+/-1.6 g/m2 per h). However, the TEWL was not deranged in patients with completely healed AD. An exfoliative cytology examination of corneal layer disclosed that patchy parakeratosis appeared in normal-appearing skin in severe, moderate and mild AD cases at a rate of 42, 29 and 19%, respectively. However, no patchy parakeratosis was recognized in patients with completely healed AD. The occurrence of patchy parakeratosis in normal-appearing skin in patients with active AD suggests that an impaired barrier function often seen in normal-appearing skin in AD patients is secondary to subclinical eczematous change in the area.     

Correlation of clinical features and skin barrier function in adolescent and adult patients with atopic dermatitis

BACKGROUND: Xerotic changes in atopic skin are considered to be related to a decrease in the water permeability barrier. Whether abnormal skin barrier function is the main cause of atopic dermatitis (AD) or a secondary change of the disease is still controversial. Noninvasive bioengineering methods, including the measurement of the transepidermal water loss (TEWL) and water capacitance, have been commonly used to evaluate skin barrier function. AIM: To evaluate the correlation between the clinical features of each evaluation site (severity of AD) and skin barrier function. METHODS: TEWL, capacitance, and pH were checked on five evaluation sites: postauricle, forearm, abdomen, thigh, and popliteal fossa. The subjects included 25 patients, both adolescents and adults, with AD and 25 age-matched normal controls. The clinical severity, from 0 (no clinical manifestation) to 3 (severe), was also scored for erythema, induration/papulation, lichenification, and xerosis on each evaluation site of the AD patients. RESULTS: Based on the data, we found that the clinical severity score was correlated with TEWL and capacitance in more than one-half of the evaluation sites. Erythema and induration/papulation showed a statistically significant correlation with TEWL in most cases (P < 0.05, four sites). Lichenification and xerosis showed a significant correlation with capacitance in most cases (P < 0.05, four sites). In most cases, severity scoring of the clinical features did not show a significant correlation with skin pH. The patients showed higher TEWL and lower capacitance than normal controls (P < 0.05, all five sites). CONCLUSIONS: The results of our study suggest that skin barrier function, measured by TEWL and capacitance, and clinical severity show a statistically significant correlation in patients with AD.     

Rarity of hypertension in adult patients with atopic dermatitis

BACKGROUND: Patients with atopic dermatitis show a tendency for vasoconstriction of the small vessels in the skin. As peripheral vasoconstriction contributes to the cause of hypertension, it is natural to suppose that blood pressures might be on the high side in adult patients with atopic dermatitis. In the literature, however, there was little information on the subject. OBJECTIVES: To study the incidence of hypertension in adult patients with atopic dermatitis. PATIENTS/METHODS: Blood pressure was measured in 521 adult patients with active atopic dermatitis (235 males; 286 females) aged 30-59 years, and 87 adults with "healed" atopic dermatitis (26 males; 61 females) aged 34-52 years. The blood pressures were classified as definite hypertension, borderline hypertension or normal blood pressure. RESULTS: In those patients aged 30-39 years with active atopic dermatitis, the incidence of definite hypertension in the male patients and the female patients was 1.1% and 1.6%, respectively. The incidence remained almost at a plateau for the 30-39-year-old age group through to the 50-59-year-old age group, in both the male and female patients. There was no difference in the incidence of definite hypertension between patients with severe dermatitis and patients with mild dermatitis. Adult patients with "healed" atopic dermatitis also showed a low incidence of definite hypertension. CONCLUSIONS: These findings indicate that hypertension is rare in adult patients with atopic dermatitis. It is most probable that the rarity of hypertension is a primary feature of the disease.