Epicutaneous aeroallergen sensitization in atopic dermatitis infants - determining the role of epidermal barrier impairment

BACKGROUND

Sensitization to atopens is an early phenomenon that overlaps with the onset of atopic dermatitis (AD) in infancy. Early epidermal barrier impairment may facilitate the epicutaneous penetration of atopens.

OBJECTIVE

To correlate transepidermal water loss (TEWL) and aeroallergen sensitization in infants with AD.

METHODS

In this cross-sectional study we enrolled 59 AD children and 30 controls aged 3-12 months. Transepidermal water loss in uninvolved skin, specific immunoglobulin E, atopy patch test (APT) and skin prick tests were performed with respect to seven aeroallergens, i.e., Dermatophagoides pteronyssinus, D. farinae, cat, dog, birch pollen, ambrosia, and cockroach. Environmental conditions were assessed by a questionnaire, and the house dust mite (HDM) concentration was determined in dust samples.

RESULTS

Eighty-nine percent of AD infants had a positive APT vs one out of eleven controls. AD infants had a significantly higher mean TEWL than controls (27.4 vs 11.1 g/m(2)/h, P < 0001). Children with two or more positive APT had higher TEWL than the others (31.1 vs 19.0 g/m(2)/h, P < 0.025). No correlation was found between indoor APT results and exposure to HDM, cats, and dogs at home.

CONCLUSIONS

This study confirms the high prevalence of delayed sensitization to indoor and outdoor aeroallergens in AD infants, and shows that the higher the TEWL, the higher the prevalence of sensitization to aeroallergens. These data are in favor of a major role of a constitutive epidermal barrier impairment in determining early atopen sensitization in infants with AD.

Oat sensitization in children with atopic dermatitis: prevalence, risks and associated factors

BACKGROUND

Topical treatments of atopic dermatitis (AD) may be responsible for cutaneous allergies. Percutaneous sensitization to oat used in emollients/moisturizers has already been reported. Our objectives were to measure the prevalence of oat sensitization in AD children, to assess its relevance, and to look at related parameters.

METHODS

We recruited prospectively children with AD referred for allergy testing between June 2001 and December 2004. Atopy patch tests (APT) and skin prick tests (SPT) to oat proteins (1%, 3% and 5%) and to the European standard series were performed followed by oral food challenge (OFC) and repeated open application test (ROAT) in the oat-sensitized group.

RESULTS

About 302 children were enrolled. Oat APT and SPT were positive in 14.6% and 19.2% of cases, respectively. Children under 2 years of age were more likely to have positive APT. In oat-sensitized children, OFC and ROAT were positive in 15.6% (five of 32) and 28% (seven of 25) of cases, respectively. Thirty-two percentage of oat cream users had oat-positive atopy patch test (APT) vs 0% in the nonusers group.

CONCLUSIONS

Oat sensitization in AD children seen for allergy testing is higher than expected. It may be the result of repeated applications of cosmetics with oats on a predisposed impaired epidermal barrier. We suggest avoiding topical-containing oat proteins in infants with AD.

The prevalence of positive reactions in the atopy patch test with aeroallergens and food allergens in subjects with atopic eczema: a European multicenter study

BACKGROUND

The atopy patch test (APT) was proposed to evaluate IgE-mediated sensitizations in patients with atopic eczema (AE).

OBJECTIVE

The prevalence and agreement with clinical history and specific IgE (sIgE) of positive APT reactions was investigated in six European countries using a standardized method.

METHODS

A total of 314 patients with AE in remission were tested in 12 study centers on clinically uninvolved, non-abraded back skin with 200 index of reactivity (IR)/g of house dust mite Dermatophagoides pteronyssinus, cat dander, grass, and birch pollen allergen extracts with defined major allergen contents in petrolatum. Extracts of egg white, celery and wheat flour with defined protein content were also patch tested. APT values were evaluated at 24, 48, and 72 h according to the European Task Force on Atopic Dermatitis (ETFAD) guidelines. In addition, skin-prick test (SPT) and sIgE and a detailed history on allergen-induced eczema flares were obtained.

RESULTS

Previous eczema flares, after contact with specific allergens, were reported in 1% (celery) to 34% (D. pteronyssinus) of patients. The frequency of clear-cut positive APT reactions ranged from 39% with D. pteronyssinus to 9% with celery. All ETFAD intensities occured after 48 and 72 h. Positive SPT (16-57%) and elevated sIgE (19-59%) results were more frequent. Clear-cut positive APT with all SPT and sIgE testing negative was seen in 7% of the patients, whereas a positive APT without SPT or sIgE for the respective allergen was seen in 17% of the patients. APT, SPT and sIgE results showed significant agreement with history for grass pollen and egg white (two-sided Pr > /Z/ < or = 0.01). In addition, SPT and sIgE showed significant agreement with history for the other aeroallergens. With regard to clinical history, the APT had a higher specificity (64-91% depending on the allergen) than SPT (50-85%) or sIgE (52-85%). Positive APT were associated with longer duration of eczema flares and showed regional differences. In 10 non-atopic controls, no positive APT reaction was seen.

CONCLUSION

Aeroallergens and food allergens are able to elicit eczematous skin reactions after epicutaneous application. As no gold standard for aeroallergen provocation in AE exists, the relevance of aeroallergens for AE flares may be evaluated by APT in addition to SPT and sIgE. The data may contribute to the international standardization of the APT.

[Squamous cell carcinoma on a leg ulcer in the West Indies]

INTRODUCTION

The epidemiology of carcinoma developing on a leg ulcer is poorly, although high incidence rates are reported in Africa.

PATIENTS AND METHODS

Retrospective study of cases reported in Guadeloupe, a tropical country with a large population from African descent and with high quality health care level.

RESULTS

Sixteen cases, mean age 71, were diagnosed over a 10-Year period in the only referral hospital. The annual incidence was an estimated 0.4/100,000. Preceding ulcers had a long course (mean of 27 Years) and had various causes. Social distress was the rule (14/16 patients). One third of the clearly differentiated (15/16) squamous cell-type tumors exhibited metastatic extension on presentation. At Year 3, the mortality rate was of 40 p. cent. The best survival rate (6 remissions/8 cases) was associated with primary limb amputation.

DISCUSSION

Malignant ulcers appeared more frequent in Guadeloupe than in the influent countries of the North, but with an instance 4-fold lower than in Africa. Like many other tropical diseases, socio-behavioral factors may play a major role.

Lupus-erythematosus-like eruption induced by Trichophyton mentagrophytes infection

BACKGROUND

Several factors are known to trigger acute manifestations of lupus erythematosus (drugs, ultraviolet radiation, bacterial or viral infections, pregnancy), but fungal infections have never been reported to induce lupus-like lesions. We describe 2 children with tinea capitis caused by Trichophyton mentagrophytes(TM), who developed transient skin and serological manifestations of systemic lupus erythematosus.

PATIENTS

Case 1, a 3-year-old girl, had a kerion due to TM transmitted by an octodon, and a facial skin eruption suggestive of systemic lupus erythematosus. Antinuclear antibodies (ANA) were positive at 1:250. After griseofulvin treatment, the lupus-like rash completely regressed, and the ANA titre decreased. Case 2, a 4-year-old girl, had occipital kerion and an annular scaly erythema on the shoulder caused by TM. She also had a non-scaly rash on the face and a recent history of photosensitivity. The ANA titre was positive at 1:8,000. Cutaneous lesions disappeared after an 8-week griseofulvin therapy, and ANA titres decreased progressively.

CONCLUSIONS

'New pets' are usually the vectors of TM, especially familiar rodents like the degu of Chile (also named octodon). In our 2 cases, lupus-like rashes began before the onset of griseofulvin treatment, suggesting a pathogenic role of the dermatophyte. A wide variety of lesions named 'mycides' was described several decades ago associated with TM infections. We hypothesize that these mycides and the TM-induced lupus-like lesions reported in our 2 cases could represent the same entity.

Atopic dermatitis: therapeutic challenge in an infant with dystrophic epidermolysis bullosa

Inherited epidermolysis bullosa (EB) manifests as blisters that usually result from minor trauma. The severity of expression ranges from mild occasional blistering to severe extensive bullae. We report an infant with dystrophic EB worsened by atopic dermatitis (AD). This concomitant skin disease exacerbated EB, because scratching induced bullae and milia. Careful management of AD provided a marked improvement in cutaneous involvement. This report shows that it is important to document and treat inflammatory skin disorders coexisting with EB, because they may influence the overall prognosis of EB.

[Blood pressure monitoring in infants with hemangiomas treated with corticosteroids]

INTRODUCTION

Alarming hemangiomas can be successfully treated with corticosteroids. The risk of hypertension is poorly documented in this setting. We conducted a prospective study in infants with hemangiomas treated with orally administered prednisone.

PATIENTS AND METHODS

Thirty-seven patients with rapidly growing complicated hemangiomas were enrolled between January 1998 and November 1999. Steroid dosages varied from 1 mg/kg/d to 5 mg/kg/d. Blood pressure measurements were performed first twice a month, then monthly at rest with a Critikon Dynamap device. Hypertension was defined as blood pressure superior to 110/60 mmHg, and borderline if superior to 110/60 mmHg on only one or two measurements.

RESULTS

Increased blood pressure was found in seven infants (19 p. 100). One infant had hypertension requiring specific treatment and blood pressure was borderline on six patients at one or two occasions. Cardiac ultrasound examination was performed in five patients revealing two cases of myocardic hypertrophy, which regressed after stopping steroids and without relationship to hypertension.

CONCLUSION

Even though the definition of hypertension in still arbitrary in infants, the measurement of blood pressure is necessary when steroid therapy is given for the treatment of hemangiomas. Blood pressure measurement can be difficult in very young children and overestimation is frequent if an inadequate device is used. The exact place of cardiac ultrasound remains to be defined in the management of alarming hemangiomas.

[Sensitization to cockroach allergens evaluated by skin tests in children with atopic dermatitis]

INTRODUCTION

Cockroach and house dust mites (Dermatophagoides pteronyssinus, Dp and farinae, Df) are the most often implicated aeroallergens in severe asthma, hay fever and conjunctivitis. Cockroach allergy is still unknown in atopic dermatitis.

PATIENTS AND METHOD

146 children with atopic dermatitis-aged 6 months to 15 years- have been patch tested with the European standard series and some aeroallergens. We have studied the sensitisation to cockroach allergens and compared to Dp and Df.

RESULTS

113 children reacted positively at least to one of the 3 aeroallergens (77 p. 100), 61 children had a positive reaction to cockroach (42 p. 100) and 29 simultaneously to the 3 allergens.

DISCUSSION

Delayed hypersensitivity to house dust mites in young children with atopic dermatitis suggests early epicutaneous sensitization due to an altered epidermal barrier. For us, cockroach could also be implicated in some flare-ups of atopic dermatitis. Eviction of cockroach and house dust mite should be proposed for children with a positive patch test to cockroach.

Asymmetric periflexural exanthem of childhood: microbiologic case-control study

Our objective was to study possible etiologic factors of asymmetric periflexural exanthem of childhood (APEC) among a large panel of microbiologic agents not yet investigated. To do so, we designed a prospective case-control study using throat, stool, blood, and skin samples, and enlisted 37 children with APEC and 37 age-matched controls without eruption seen consecutively from February 1995 to April 1996 from a mixed referral center and community-based population. No interventions were done. Used as the main outcome measure was the differences in the two groups for microbiologic investigations. No significant statistical differences between cases and controls for virus and bacteria investigated were found. No microorganism was identified as a possible etiologic agent in any of the APEC patients. APEC is not a nonspecific cutaneous eruptive pattern to several common microbiologic agents. More sophisticated molecular approaches are needed to address its etiology.

Crusted (Norwegian) scabies induced by use of topical corticosteroids and treated successfully with ivermectin

Crusted scabies is mainly observed in children with immunosuppression or mental illness. Treatment is very difficult, and relapse is frequent after topical scabicidal therapy. We describe a case of crusted scabies, induced by long-term application of a topical corticosteroid, relapsing after topical treatment and dramatically improved by ivermectin. We suggest that ivermectin is a safe and effective alternative therapy for the treatment of severe Sarcoptes scabiei infestation in children unresponsive to conventional treatment.

Usefulness of the European standard series for patch testing in children. A 3-year single-centre study of 337 patients

Results of patch tests in 337 children aged 1 to 15 performed in our paediatric unit during the past 3 years have been analysed retrospectively in order to optimize the patch test series and to assess their relevance. This study represents the most important single-centre study reported so far over a short period. We found a positive patch test rate of 66%, with a peak incidence among children less than 3 years of age (88% versus 58.9%). The most common allergens were metals, especially nickel, fragrances and, less frequently, rubber chemicals. Concerning nickel, positive reactions rarely correlated with a relevant exposure and were difficult to interpret, especially in patients with atopic dermatitis, who are probably more likely to have irritant or false-positive reactions to metals. Based on the results and their relevance, we propose a shortened standard series of patch tests for paediatric patients.

[Classification and management of mastocytosis in the child]

OBJECTIVE

Mastocytosis is a frequently observed condition in children. We analyzed the initial manifestations and clinical course.

PATIENTS AND METHODS

We restrospectively studied 49 cases of mastocytosis in children (29 boys and 20 girls) managed in our unit between 1985 and 1995. All of the children had typical manifestations. Photographic documents were available in all cases.

RESULTS

There was pigmentary urticaria in 32 cases and a mastocytoma in 17. Axanthelasmoid aspect and bullae were observed in some cases in both of these clinical forms. Complementary explorations demonstrated one case of duodenal mast cell infiltration. Excepting the case with skin and duodenal manifestation, all of our patients improved and clinical cure was obtained during growth.

DISCUSSION

The association of dermal atopia and mastocytosis does not influence the clinical course of these two conditions. The development of bullae does not appear to be a factor of poor prognosis. The xanthelasmoid aspect of the lesions and the similar course in childhood mastocytosis and juvenile xanthogranulma would suggest that a common process with a histological spectrum including mastocytoma and xanthoma is involved. In our experience, counselling against the use of anti-cough medicines containing codeine is an essential part of management. Antihistamine agents may be prescribed for pruritus.

Mutations in the hair cortex keratin hHb6 cause the inherited hair disease monilethrix

Pathogenic mutations in a large number of human epithelial keratins have been well characterized. However, analogous mutations in the hard alpha-keratins of hair and nail have not yet been described. Monilethrix is a rare autosomal dominant hair defect with variable expression. Hairs from affected individuals show a beaded structure of alternating elliptical nodes and constrictions (internodes). These internodes exhibit a high prospensity to weathering and fracture. Strong evidence that trichocyte keratin defects might underlie this hair disorder was provided by genetic linkage analyses that mapped this disease to the type-II keratin gene cluster on 12q13. All affected individuals from a four-generation British family with monilethrix, previously linked to the type-II keratin gene cluster, as well as three unrelated single monilethrix patients, exhibited a heterozygous point mutation in the gene for type-II hair cortex keratin hHb6, leading to lysine substitution of a highly conserved glutamic acid residue in the helix termination motif (Glu 410 Lys). In a three-generation French family with monilethrix of a milder and variable phenotype, we detected another heterozygous point mutation in the same glutamic acid codon of hHb6, which resulted in a conservative aspartic acid substitution (Glu 410 Asp). These mutations provide the first direct evidence for involvement of hair keratins in hair disease.

Footwear contact dermatitis in children

8 children aged 1 to 13 years, clinically suspected of having contact dermatitis due to footwear, have been studied in our Paediatric Dermatology Unit from January 1980 to September 1995. Patch tests have been performed with the European standard series and with constituents of the patients' own shoes. In our study, patients appeared to be predominantly sensitive to rubber chemicals. Avoiding shoes or materials that had been identified improved the symptoms in most cases.

[Cerebrovascular accidents and AIDS]

A number of pathological and clinical data suggest that AIDS could be an underestimated cause of cerebro-vascular disease, especially in young individuals. Eight retrospective cases of stroke in AIDS patients are reported. Mean age was 39 years, mean CD4 cells count 57/mm3. Pathogenic mechanism, particularly the role of opportunistic infections remains unclear. Prognosis does not seem constantly pejorative: only one patient died from stroke, six are still alive with a 6 months follow-up, without relapse and with minor or no sequellae. Alcohol or cocaine (crack) abuse was present in half the cases. The role of specific risk factors and consequently adapted prophylaxis is questionned.

[Prurigo in tropical area. Importance of its association with HIV infection]

The term prurigo applies to a classic chronic skin disease of children (P. strophulus) which is becoming found very seldom in developed countries, but remains extraordinarily prevalent in tropical areas. This striking geographical distribution relies on its ectoparasitic origin. Some peculiar aspects of prurigo, observed in French Guyana (South America), are reported. The original point is a new aspect of adult acquired prurigo, associated with HIV infection, which appears to be one of the features characteristic of tropical AIDS. This HIV associated prurigo (HAP) is the revelating event, in as high as 20% of HIV infected people, significatively those with less than 200 CD4 cells. HAP appears as a marker of HIV infection with poor sensitivity, but much higher specificity (92%), with no correlation with acquisition's risk factors. Just like infantile prurigo, HAP can be considered an arthropod bite reaction which seems to be enhanced in HIV infected people living in tropical environment.