Immediate hypersensitivity to Malassezia furfur and Candida albicans mannans in vivo and in vitro

BACKGROUND: Elevated and correlative Malassezia furfur (M. furfur) and Candida albicans (C. albicans) mannan-specific IgE have been demonstrated in atopic eczema dermatitis syndrome (AEDS) of the head, neck and shoulder (HNS) region of the skin. The significance of these antibodies in vivo has not been demonstrated. METHODS: Sixty-five AEDS patients with HNS distribution were included. Serum total IgE (S-IgE) and yeast antigen-specific (Cetavlon-purified mannan and whole extract antigens of M. furfur and C. albicans) IgE were measured and skin prick tests (SPT) were performed with the yeast antigens. RESULTS: Mannan-specific IgE and SPT were positive in 51 and 48% of patients with M. furfur and in 42 and 22% with C. albicans, respectively. Whole extract-specific IgE and SPT were positive in 85 and 95% of patients with M. furfur and in 91 and 57% with C. albicans, respectively. The highest correlation between specific IgE and SPT was seen with M. furfur mannan (r = 0.60; P < 0.0001). Both M. furfur mannan-specific IgE (r = 0.76; P < 0.0001) and SPT (r = 0.44; P = 0.0005) correlated with S-IgE. CONCLUSIONS: Mannan-induced immediate hypersensitivity in vivo was demonstrated in SPT. The significant correlation between M. furfur mannan-specific IgE and SPT suggests that mannan is an important allergen in yeast hypersensitive AEDS in vivo.     

Fungi and atopic dermatitis]

Attention has recently been centered on fungi as aggravating factors of atopic dermatitis (AD) due to the frequent detection of IgE antibodies to fungi in patients with severe AD and to positive response of some cases of AD to antifungal therapy. Malassezia sp.: In AD patients with prominent symptoms in the head and neck, areas prone to colonization by Malassezia, the titers of specific anti-Malassezia IgE antibodies are high, which positively correlate with the total IgE value and the severity of AD. The patch test against Malassezia antigens is positive. The rate of isolation of Malassezia from the skin of AD patients is higher than that from the skin of healthy control subjects. Candida sp.: In patients with severe AD, the rate of positive skin prick tests for Candida is high, and a correlation exists between positive skin prick test results and the presence of Candida albicans in nasopharynx. However, the reactivity to Candida antigens in the patch tests is reduced, and a negative correlation is seen. There is no difference between the isolation rate of C. albicans from patients with adult-type AD and normal controls. However, AD patients give a significantly greater number of separate colonies. The range of efficacy rate of antifungal therapy of AD is reported to be 50-65 %. The efficacy rate of our own trial falls within this range. Following treatment, the rate of isolation of fungi decrease significantly, and the titers of specific antifungal IgE antibodies are not statistically significant. The clearance of fungi from the tissue following antifungal therapy probably results in the suppression of direct or indirect inflammatory reaction caused by the fungi. We therefore consider antifungal therapy as one of the second-line therapies to be administered in AD cases resistant to conventional basic therapy.     

Learning from fungus allergy in atopic dermatitis patients]

It has been recognized that there are considerable variations in their skin reactivity to environmental allergens as well as in immunoreactivities, even in AD patients with similar signs and symptoms. Some AD patients have high serum IgE antibody levels, while others show low levels. There are also differences in the kinds of triggering factors that are related to the development and maintenance of AD, e.g., allergic or non-allergic. Even among AD patients with high titers of serum IgE antibodies, the kinds and number of allergens involved in the exacerbation of AD are different and can change with time. The types of the underlying allergic reactions vary as well, i.e., some show immediate reactions, while others show delayed type hypersensitivity responses to environmental allergens. Thus, even AD patients diagnosed by the established criteria may have remarkably different backgrounds. When we looked over our published data, we noticed that there were differences in levels of IgE RAST and skin reactions between AD with atopic respiratory diseases (ARD) and pure AD without ARD. Levels of IgE RAST against airborne allergens, which come into the body mainly through the respiratory tract, were higher in AD with ARD, while those against allergens such as Candida albicans and Malassezia furfur, which can colonize on the skin, were higher in pure AD. In addition to these Th2-mediated immunological abnormalities, Th1-mediated DTH reaction and lymphocyte proliferation indices against airborne allergens were remarkably low in AD with ARD, whereas those against Candida albicans and Malassezia furfur were relatively preserved, although they were lower than those found in normal subjects. We understand from these findings that routes of allergen entry are important for the outcome of the resultant allergic reactions. This point of view is important answering questions such as how AD develops and how it can be prevented from the insults of each allergen.     

Skin prick test reactions to brewer's yeast (Saccharomyces cerevisiae) in adult atopic dermatitis patients

The sensitizing capacity of brewer's yeast ( Saccharomyces cerevisiae ) was studied with the skin prick test method in 449 subjects, including 226 atopic dermatitis (AD) patients, 50 patients with allergic rhinitis (AR) and/or asthma (A), and 173 nonatopic controls. A positive SPT reaction (≥++) was seen in 94% of patients with severe AD, in 76% with moderate AD, and in 25% with mild AD or no history of AD. Patients with AR and/or A and nonatopic controls displayed a positive reaction in only 8 and 2% of cases, respectively. There was also a parallel skin prick test reactivity with other yeasts including Pityrosporum ovale and Candida albicans , suggesting cross-reactivity. Parallel skin reactivity was observed also with molds and animal dander but not with pollen or house-dust mite. A significant correlation was also found between total serum IgE level and skin prick test (SPT) results with S. cerevisiae .     

Use of specific IgE in assessing the relevance of fungal and dust mite allergens to atopic dermatitis: a comparison with asthmatic and nonasthmatic control subjects

BACKGROUND: Although allergens have been implicated as aggravating factors in atopic dermatitis (AD), there is little epidemiologic data on the significance of specific IgE. OBJECTIVE: We sought to compare sensitization to dust mite and fungi between patients with AD and asthmatic and nonasthmatic control subjects. METHODS: Total IgE and specific IgE to Dermatophagoides pteronyssinus, Alternaria alternata, Aspergillus fumigatus, Candida albicans, Malassezia furfur, and Trichophyton rubrum were measured in 73 patients with moderate to severe AD. Total IgE and IgE specific for D pteronyssinus, A alternata, and M furfur were also measured in sera from 156 asthmatic and 212 nonasthmatic control subjects. RESULTS: Positive correlations were found between total IgE and IgE antibodies specific for each of the antigens. IgE specific for M furfur was observed more frequently in adults compared with children with AD (P <.01). AD sera had higher levels of total IgE and a higher prevalence of positive sera to D pteronyssinus (95% vs 42% and 17% for subjects with AD, asthmatic subjects, and nonasthmatic subjects, respectively), M furfur (53% vs 1% and 0.5%), and A alternata (49% vs 29% and 18%). Among the sera from subjects allergic to mites, the contribution of IgE specific for D pteronyssinus to the total IgE levels was similar regardless of the clinical status. CONCLUSIONS: Our results demonstrate that moderate-to-severe AD is strongly associated with sensitization to dust mite andM furfur (odds ratios, 45.6 and 132 vs pooled control sera). These results suggest that both environmental allergens and colonizing fungi contribute to the severity of disease, which is consistent with the view that mite avoidance and antifungal treatment can be beneficial in the treatment of these patients.     

Malassezia and atopic dermatitis]

Although many exacerbating factors for atopic dermatitis (AD) have been discussed, we are focusing on fungus antigen as a pathogenesis for this condition. About half of the patients were sensitized by Candida albicans and/or Malassezia furfur (MF) using IgE. Patients with severe eruption tended to have a higher concentration of specific IgE. IgE to purified antigens such as manganese superoxide dismutase (MnSOD), cyclophilin, and Malf2 from MF was also detected, while the pattern of positive IgE was varied among the patients so that the major allergen could not be determined. Skin testing gave a positive reaction to MF after 24 hours as well as an immediate type reaction; this delayed type reaction was AD specific since a small number of patients with bronchial asthma showed a positive response to MF. Peripheral mononuclear cells co-cultured with crude MF antigen in vitro produced IL-5 in some AD patients. This response was correlated with the severity of facial eruption, indicating that Th2 type response to MF might make these eruptions worse. MF was easily detected from various skin regions,but we were not able to explain why fewer colonies were obtained from a region with dermatitis than from a non-dermatitis region. From these results, we speculate there are patients who have IgE and Th2 cells which respond to MF. The exact mechanism, however, is still obscure as to how normal flora such as MF can react and exacerbate AD. Further investigations should be done to learn more about the relationship between AD and MF.     

Molecular and quantitative analyses of Malassezia microflora on the skin of atopic dermatitis patients and genotyping of M. globosa DNA]

To elucidate the role of Malassezia species in atopic dermatitis (AD) requires investigation of the Malassezia microflora on the skin of AD patients. Previously, M. furfur was considered the dominant species in the microflora, however, this microorganism has been reclassified into five species and reanalysis of the microflora based on the current Malassezia taxonomy is therefore needed. Malassezia is more difficult to isolate and culture than other pathogenic yeasts such as Candida and Cryptococcus, making it difficult to elucidate the microflora of AD patients accurately. We developed a PCR-based non-culture method that does not require the use of isolation or culture techniques. Of the members of the genus Malassezia, M. globosa colonized the skin of both AD patients and healthy subjects more frequently than other Malassezia species. In addition, we found polymorphisms in the intergenic spacer 1 region of the M. globosar RNA gene. The genotypes of the microorganisms obtained from AD patients were significantly different from those obtained from healthy subjects. We believe that a specific genotype of M. globosa is responsible for exacerbation of AD.     

Molecular analysis of Malassezia microflora on the skin of atopic dermatitis patients and healthy subjects

Members of the genus Malassezia, lipophilic yeasts, are considered to be one of the exacerbating factors in atopic dermatitis (AD). We examined variation in cutaneous colonization by Malassezia species in AD patients and compared it with variation in healthy subjects. Samples were collected by applying transparent dressings to the skin lesions of AD patients. DNA was extracted directly from the dressings and amplified in a specific nested PCR assay. Malassezia-specific DNA was detected in all samples obtained from 32 AD patients. In particular, Malassezia globosa and M. restricta were detected in approximately 90% of the AD patients and M. furfur and M. sympodialis were detected in approximately 40% of the cases. The detection rate was not dependent on the type of skin lesion. In healthy subjects, Malassezia DNA was detected in 78% of the samples, among which M. globosa, M. restricta, and M. sympodialis were detected at frequencies ranging from 44 to 61%, with M. furfur at 11%. The diversity of Malassezia species found in AD patients was greater (2.7 species detected in each individual) than that found in healthy subjects (1.8 species per individual). Our results suggest that M. furfur, M. globosa, M. restricta, and M. sympodialis are common inhabitants of the skin of both AD patients and healthy subjects, while the skin microflora of AD patients shows more diversity than that of healthy subjects. To our knowledge, this is the first report of the use of a nested PCR as an alternative to fungal culture for analysis of the distribution of cutaneous Malassezia spp.     

Molecular analysis of malassezia microflora on the skin of atopic dermatitis patients and healthy subjects]

We compared cutaneous colonization levels of Malassezia species in patients with AD and healthy subjects using nested PCR. Malassezia-specific DNA was detected in all 32 of the patients with AD. M. globosa and M. restricta were detected in approximately 90% of these patients, with M. furfur and M. sympodialis being detected in approximately 40% of the cases. In healthy subjects, Malassezia DNA was detected in 78% of the samples, M. globosa, M. restricta and M. sympodialis were detected at frequencies ranging from 44 to 61%, and M. furfur was found in 11% of healthy subjects. Our results suggest that M. furfur, M. globosa, M. restricta and M. sympodialis are common inhabitants of the skin of both AD patients and healthy subjects, while the skin microflora of patients with AD shows more diversity than that of healthy subjects.     

Comparison of skin prick tests with specific serum immunoglobulin E in the diagnosis of fungal sensitization in patients with severe asthma

Background It has been shown that patients with allergic bronchopulmonary aspergillosis (ABPA) and patients with severe asthma with fungal sensitization (SAFS) can benefit from antifungal therapy. It is not known whether allergy skin prick tests (SPT) or specific IgE tests are more sensitive in the identification of patients who are sensitized to fungi and who are therefore candidates for antifungal therapy.
Objectives To compare SPT and specific serum IgE tests for fungal sensitization in patients with severe asthma.
Methods We have undertaken SPT and specific serum IgE tests to six fungi ( Aspergillus fumigatus, Candida albicans, Penicillium notatum, Cladosporium herbarum, Alternaria alternata and Botrytis cineria ) and specific serum IgE test for Trichophyton in 121 patients with severe asthma (British Thoracic Society/SIGN steps 4 and 5).
Results Sixty-six percent of patients were sensitized to one or more fungi based on SPT and/or specific serum IgE results. Positivity to SPT and/or specific serum IgE was as follows: A. fumigatus 45%, C. albicans 36%, P. notatum 29%, C. herbarum 24%, A. alternata 22%, B. cineria 18%, Trichophyton 17% (specific serum IgE only). Concordance between the tests was 77% overall but only 14–56% for individual fungi. Twenty-nine (24%) patients were sensitized to a single fungus and seven (6%) were sensitized to all seven fungal species. Fifty percent of patients were sensitized to fungal and non-fungal extracts, 21% were sensitized only to non-fungal extracts, 16% were sensitized only to fungal extracts and 13% had no positive tests.
Conclusion This study is consistent with previous reports that fungal sensitization is common in patients with severe asthma. At present, it remains necessary to undertake both SPT and specific serum IgE testing to identify all cases of fungal sensitization. This may be important in the identification of patients with ABPA and SAFS who may benefit from antifungal therapy.     

Pityriasis versicolor and Malassezia folliculitis]

Pityriasis versicolor and malassezia folliculitis were studied clinically and mycologically. The main results were as follows: 1) The average age of pityriasis versicolor patients has gradually become higher. 2) Negative rates of Malassezia furfur after treatment were very high by direct examination but relatively low by culture. 3) Patients who were negative by culture on completion of treatment seldom recurred within 2 months. 4) We can evaluate the effectiveness of antifungal application by using Malassezia furfur as normal skin flora on the volunteer's back. 5) Malassezia furfur (orbiculare or ovale type) is detected in follicular contents of steroid acne and acne vulgaris, which makes it necessary to establish criteria for diagnosis of malassezia folliculitis.     

Combined skin prick and patch testing enhances identification of peanut-allergic patients with atopic dermatitis

BACKGROUND: Food atopy patch tests (APTs) are considered a useful tool for the diagnosis of food allergy. Hypersensitivity to peanuts has not been investigated by means of APTs so far. METHODS: APTs and skin prick tests (SPTs) with peanuts were performed in 136 atopic dermatitis (AD) patients. Relevance of positive and negative responses to these tests was assessed by repeated open challenges with peanuts. RESULTS: Nine percent of our AD patients reacted to the challenge. Positive responses to APTs were recorded in 19% of the patients, whereas in 12% positive SPTs were observed. APTs were more frequently positive in subjects with eczematous responses after challenge with respect to those with urticarial reactions. SPT reactivity proved to be higher in patients above 12 years of age, whereas APT positivity was more frequent in children under 6 years. APT sensitivity proved significantly higher than SPT sensitivity, in particular in children under 12 years of age. On the contrary, SPT specificity and positive predictive value were significantly higher with respect to those of APT in the age group of subjects under 6 years of age. CONCLUSIONS: Our data suggest that APTs with peanuts may represent a useful integration to standard testing modalities employed for the diagnosis of peanut allergy in AD patients.     

New and emerging yeast pathogens.

The most common yeast species that act as agents of human disease are Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Cryptococcus neoformans. The incidence of infections by other yeasts has increased during the past decade. The most evident emerging pathogens are Malassezia furfur, Trichosporon beigelii, Rhodotorula species, Hansenula anomala, Candida lusitaniae, and Candida krusei. Organisms once considered environmental contaminants or only industrially important, such as Candida utilis and Candida lipolytica, have now been implicated as agents of fungemia, onychomycosis, and systemic disease. The unusual yeasts primarily infect immunocompromised patients, newborns, and the elderly. The role of central venous catheter removal and antifungal therapy in patient management is controversial. The antibiograms of the unusual yeasts range from resistant to the most recent azoles and amphotericin B to highly susceptible to all antifungal agents. Current routine methods for yeast identification may be insufficient to identify the unusual yeasts within 2 days after isolation. The recognition of unusual yeasts as agents of sometimes life-threatening infection and their unpredictable antifungal susceptibilities increase the burden on the clinical mycology laboratory to pursue complete species identification and MIC determinations. Given the current and evolving medical practices for management of seriously ill patients, further evaluations of the clinically important data about these yeasts are needed.     

Analysis of IgE reactivities of purified allergens from Candida albicans and Malassezia furfur among patients with atopic dermatitis]

We analyzed the reactivities of a series of purified allergens from Candida albicans (C. albicans) and Malassezia furfur (M. furfur) with IgE antibodies in sera from patients with atopic dermatitis. We compared the specific IgE antibody levels to manganese superoxide dismutase (Mn SOD), cyclophilin, enolase, secretory aspartic protease (SAP 2) and type A mannan from C. albicans and Mn SOD, cyclophilin and Mal f 2 from M. furfur in 21 sera from patients with atopic dermatitis and 20 sera from patients with asthma without atopic dermatitis. The prevalence of IgE antibodies and the mean IgE antibody levels to all of the allergens tested were higher among patients with atopic dermatitis than among those with asthma without atopic dermatitis. More than 50% of patients with atopic dermatitis were IgE antibody-positive to Mn SOD, cyclophilin and type A mannan from C. albicans, and Mn SOD and cyclophilin from M. furfur. The availability of these purified allergens will facilitate studies on the contribution of fungal allergens to the development of atopic dermatitis.     

Uptake of the yeast Malassezia furfur and its allergenic components by human immature CD1a+ dendritic cells

Atopic dermatitis (AD) is a chronic inflammatory skin disease with increasing prevalence, though still little is known of the pathomechanisms and the causes of the disease. Patients with AD often have specific IgE reactivity to the yeast Malassezia furfur (M. furfur), present in the normal microflora on human skin. To investigate the possible interaction of immature and mature antigen-presenting dendritic cells with the yeast M. furfur and its allergenic components. Monocyte-derived dendritic cells (MDDCs) generated from human peripheral blood were allowed to interact with FITC-labelled whole M. furfur yeast cells, M. furfur extract, a recombinant allergen from M. furfur designated rMal f 5 and M. furfur mannan, in the absence of IgE antibodies. Interaction and uptake were detected using flow cytometry and confocal laser scanning microscopy. Internalization of M. furfur yeast cells and yeast components by immature MDDCs was found using confocal laser scanning microscopy. Results from flow cytometric studies showed that a median of 94% (range, 65-98%) of the immature CD1a+ MDDCs were M. furfur extract positive, 81% (75-97%) rMal f 5 positive and 93% (62-98%) mannan positive. Mature CD1a+ MDDCs were significantly less efficient in this respect, with the corresponding figures only 26% (6-37%, P < 0.01), 6% (2-15%, P < 0.05) and 32% (9-50%, P < 0.01), respectively. Uptake of the non-glycosylated rMal f 5 by immature CD1a+ MDDCs was decreased to 27% (15-38%) by inhibition of pinocytosis. The binding of M. furfur extract and mannan was inhibited in a dose-dependent manner by methyl-alpha-D-mannopyranoside, suggesting uptake via the mannose receptor. Human immature CD1a+ MDDCs can efficiently take up M. furfur and allergenic components from the yeast in the absence of IgE antibodies, implying that sensitization of AD patients to M. furfur can be mediated by immature dendritic cells in the skin.     

Nasal polyposis: a study of its association with airborne allergen hypersensitivity.

BACKGROUND: Despite the frequent presence of clinical symptoms such as sneezing and itching, elevated histamine and IgE in extracellular polyp fluids, tissue eosinophilia, and degranulated mast cells, allergy is not considered an important cause of nasal polyposis. OBJECTIVE: To investigate the prevalence of immediate skin reactivity to airborne allergens in patients with nasal polyposis. METHODS: Sixty-eight patients with nasal polyposis and 36 controls with chronic sinusitis were submitted to skin prick tests (SPTs) with a large series of seasonal and perennial airborne allergens including: grass, mugwort, ragweed, pellitory, plantain, birch, hazel, olive, cypress, house dust mites, cat and dog dander, and thirteen molds (Alternaria, Aspergillus, Cladosporium, Penicillium, Candida, Trichophyton, Fusarium, Curvularia, Botrytis, Pullularia, Rhizopus, Mucor, Helminthosporium). RESULTS: Forty-three of 68 (63%) patients with nasal polyposis versus 6 of 35 (17%) controls were positive on SPT with airborne allergens (P < .001). A comparison with 1,128 subjects with respiratory allergy seen from 1996 to 1999 showed a markedly higher prevalence of sensitivity to Candida albicans (19 of 43 [44%] vs 8 of 1,128 [1%]; P < .001) and to house dust mites (12 of 43 [28%] vs 154 of 1,128 [14%]; P < .05) among allergic patients with polyps. Altogether, 30 of 43 (70%) patients versus 215 of 1,128 (19%) controls were sensitive to at least one perennial airborne allergen (ie, mold, mite, or animal dander) on SPT (P < .001); in contrast, 26 of 43 (60%) patients versus 942 of 1,128 (84%) controls were sensitive to seasonal airborne allergens (P < .005). A review of the clinical histories of SPT-positive patients revealed the presence of obstructive rhinitis and chronic rhinorrhea only in most cases, whereas acute symptoms, such as sneezing and itching, were reported only by a minority of subjects. CONCLUSIONS: A clinically slight respiratory allergy, particularly to perennial airborne allergens, might play a relevant role in the pathogenesis of nasal polyposis, probably through the induction of a long-lasting inflammation of the nasal mucosa.     

The skin fungus-induced Th1- and Th2-related cytokine, chemokine and prostaglandin E2 production in peripheral blood mononuclear cells from patients with atopic dermatitis and psoriasis vulgaris

BACKGROUND: It is suggested that skin fungi may be involved in the development of atopic dermatitis (AD) and psoriasis vulgaris (PV). OBJECTIVE: We studied skin fungus-induced Th1- or Th2-related cytokine, chemokine and prostaglandin E2 (PGE2) secretion in peripheral blood mononuclear cells (PBMC) from patients with AD and PV and normal subjects. METHODS: PBMC were cultured with the extracts of Malassezia furfur (MF), Candida albicans (CA) and Trichophyton rubrum (TR). The cytokine, chemokine and PGE2 amounts in the supernatants were measured by enzyme-linked immunosorbent assays. RESULTS: MF induced IL-4 and macrophage-derived chemokine (MDC) secretion in AD patients, while induced IFN-gamma and interferon-inducible protein of 10 kDa (IP-10) secretion in PV patients, however, did not induce either secretion in normal subjects. CA induced IL-4, MDC, IFN-gamma and IP-10 secretion in AD and PV patients and normal subjects. In AD patients, the magnitude of IL-4 and MDC responses to CA was higher than that to MF. Compared with PV patients and normal subjects, the magnitude of IL-4 and MDC responses to CA was higher while that of IFN-gamma and IP-10 responses to CA was lower in AD patients. TR induced moderate IL-4 and MDC secretion only in AD patients. The three fungi induced higher levels of PGE2 secretion in AD patients than in PV patients and normal subjects. Cyclooxygenase-2 inhibitor NS-398 suppressed PGE2 responses to MF, CA and TR, and partially suppressed IL-4 and MDC responses to MF, CA and TR, while enhanced IFN-gamma and IP-10 responses to CA in AD patients, and these effects of NS-398 were reversed by cyclic AMP analogue. CONCLUSION: AD patients manifest Th2-skewed responses to MF, CA and TR, which may be partially attributable to the enhanced PGE2 responses to these fungi. PV patients manifest Th1-skewed responses to MF.     

Relationship of immediate and delayed hypersensitivity to nasopharyngeal and intestinal growth of Candida albicans in allergic subjects

The growth of C. albicans yeast in the nasopharynx and in the anus as well as allergy symptoms were followed up for 8 months in 67 patients with bronchial asthma, allergic rhinitis and/or atopic eczema. 38 of the patients were skin prick test positive and 29 negative to C. albicans allergen extract. 32 of the patients had positive and 19 negative delayed skin reactions. The nasal, bronchial and skin symptoms of the yeast-sensitive allergic patients were not associated with the nasopharyngeal nor anal occurrence of C. albicans or other yeasts. The use of nasal or inhaled steroids had no effect on the occurrence of Candida in the nasopharynx. It was observed that immediate skin sensitivity had a positive correlation and the delayed sensitivity a negative correlation with the occurrence of C. albicans growth in nasopharynx and anus. These findings are in agreement with the concept that impaired cell-mediated immunity to C. albicans may lead to increased IgE response. This may explain the increased liability towards C. albicans nasopharyngeal and gastrointestinal "saprophytic" growth.     

Concurrent cereal allergy in children with cow''s milk allergy manifested with atopic dermatitis

BACKGROUND: There is increasing consensus about the significance of food allergens in the pathogenesis of atopic dermatitis (AD) in infancy and childhood, with cow's milk and egg accounting for most of the reactions. Previous studies have indicated that multiple food sensitization, such as cereals, is very common in patients with cow's milk allergy (CMA). Evidence is lacking, however, as to its clinical relevance. OBJECTIVE: The purpose of this study was to determine the concurrent occurrence of cereal allergy among children with challenge-proven CMA who have residual symptoms, such as AD and/or gastrointestinal symptoms, during cow's milk elimination diet. Further, we sought to evaluate the utility of patch testing in prescreening foods other than cow's milk behind allergic symptoms in children. METHODS: The study population comprised 90 children, aged from 2.5 to 36 months (mean 1.1 years), with challenge-proven CMA. As a result of residual symptoms during meticulous cow's milk elimination diet (AD: n=80, and gastrointestinal: n=10), the children were put on a cereal elimination diet (oats, wheat, rye, and barley) and skin prick tests (SPT) and patch testing with cereals were performed. Open cereal challenge was performed to confirm cereal allergy. RESULTS: Cereal challenge was positive in 66 (73%) of the children with CMA. Of them, 17% reacted with immediate reactions and delayed-onset reactions were seen in 83% of the children. SPT was positive in 23%, patch test in 67%, and either SPT or patch test was positive in 73% of the children with cereal allergy. SPT gave the best positive predictive value, whereas SPT together with patch test gave the best negative predictive value. CONCLUSIONS: Residual symptoms, such as eczema or gastrointestinal symptoms in CMA children may be a sign of undetected allergy to other food antigens. SPT with cereals aids in diagnosing cereal allergy in small children, especially when used together with patch testing.     

Malassezia furfur in infantile seborrheic dermatitis

Our objective was to study both incidence and various strains of Malassezia in infantile seborrheic dermatitis (ISD). Sixty infants between 2 weeks and 2 years old with clinical diagnosis of ISD at the Department of Pediatrics, King Chulalongkorn Memorial Hospital from May 2002 to April 2003 were recruited. Malassezia spp. were isolated from cultured skin samples of the patients, genomic DNA was extracted and the ITS1 rDNA region was amplified. The PCR product was examined by agarose gel electrophoresis and DNA sequences were determined. The ITS1 sequences were also subjected to phylogenetic analysis and species identification. ISD is most commonly found in infants below the age of 2 months (64%), followed by those between 2 and 4 months (28%) old. Cultures yielded yeast-like colonies in 15 specimens. PCR yielded 200-bp products (Candida) in 3 patients and 300-bp products (Malassezia furfur) in 12 patients (18%). Sugar fermentation using API 20C aux performed on the three 200-bp PCR products yielded Candida species. M. furfur was the only Malassezia recovered from skin scrapings of children with ISD.