Prevalence of rat and mouse sensitization in Asian patients with respiratory allergy.

BACKGROUND: Skin prick test (SPT) is useful in identifying rat and mouse sensitization. OBJECTIVE: To determine the prevalence of rat and mouse sensitization by using local and commercial allergen extracts. METHODS: Patients with allergic rhinitis or asthma were recruited. SPT of local and commercial rat and mouse allergen extracts were performed. The level of rat and mouse specific IgE (sIgE) was quantified in all patients with positive SPT and randomized patients with negative SPT. RESULTS: Two hundred and thirty patients, 108 male (47%) and median age 14 years (3.2-63.5 years), were enrolled. Rat sensitization by SPT was 11.7% and mouse sensitization was 17.8%. SPT result to local rat and commercial rat allergen extracts were moderately correlated (rs = 0.51, p < 0.001), while SPT result to local mouse and commercial mouse allergen extracts showed low correlation (rs = 0.38, p < 0.001). The concordance of SPT results between local rat and commercial rat allergen extracts was 90.4%. Concordance between the local mouse and commercial mouse allergen extracts was 85.2%. When compared with rat and mouse sIgE, the concordance of local rat, commercial rat and commercial mouse allergen extract were > 80% while that of local mouse was 54.4%. No adverse effect was observed in SPT with any allergen or extract. CONCLUSIONS: The prevalence of rat and mouse sensitization was low compared to the study in USA. SPT with local rat and mouse allergen extract was safe and showed good concordance with the SPT result of commercial allergen extracts and rat and mouse sIgE levels.

Clinical practice guidelines for the diagnosis and management of atopic dermatitis.

Atopic dermatitis (AD), a chronic, relapsing dermatitis, is characterized by dry and pruritus skin in patients with a personal or family history of atopy. It affects up to 20% of children and 1-3% of adults in most countries worldwide, and leads to significant treatment costs and morbidity. These guidelines are developed in accordance with evidence-based publications and expert opinions. Following simple algorithms, the guidelines aim to assist adult and pediatric physicians in the better care of patients with AD. As with other diseases, there have been several diagnosis criteria proposed over time. Nonetheless, the classical Hanifin and Rajka criterion with no pathognomonic laboratory biomarkers is still the most widely used worldwide for the diagnosis of AD. The management of AD must be considered case by case to provide suitable care for each patient. Basic therapy is focused on avoiding specific/unspecific provoking factors and hydrating skin. Topical anti-inflammatory treatments such as glucocorticoids and calcineurin inhibitors are suggested for disease flare, and proactive therapy is best for long-term control. Other therapies, including antimicrobial agents, systemic antihistamines, systemic anti-inflammatory agents, immunotherapy, phototherapy, and psychotherapy, are reviewed in these guidelines. Crisaborole, a new topical phosphodiesterase 4 inhibitor, can be used twice daily in AD patients over three months old. Dupilumab, a biological drug for patients with moderate-to-severe AD, may be considered in patients with no improvement from other systemic treatments.

Accuracy of in-house alcohol-dissolved wheat extract for diagnosing IgE-mediated wheat allergy.

BACKGROUND: The standard method for diagnosing immediate wheat allergy is oral food challenge test (OFC). However, OFC can provoke anaphylaxis during the challenge process. Skin prick test (SPT) using commercial wheat extract yielded unsatisfactory result for diagnosis of wheat allergy. As a result, an in-house, alcohol-dissolved (Coca-10% EtOH) wheat extract was developed to improve accuracy of the SPT. OBJECTIVE: To determine the accuracy of in-house, alcohol-dissolved wheat extract in children with immediate wheat allergy. METHODS: This prospective cross-sectional study included children with history of immediate reaction after wheat ingestion. SPTs with commercial and in-house Coca-10% EtOH wheat extract were performed and wheat and omega-5 (ω-5) gliadin specific IgE (sIgE) were measured. Patients with no history of recent anaphylaxis after wheat ingestion underwent OFC with 31 grams of wheat flour. RESULTS: Thirty children were recruited. Thirteen of those had history of anaphylaxis after wheat ingestion. Eleven of the remaining 17 children (64.7%) had a positive result for wheat challenge test. Wheal size of 3 mm for both in-house and commercial wheat extract yielded the best accuracy for the test. Using these cutoff parameters, in-house Coca-10% EtOH wheat extract yielded 91.7% sensitivity, 66.7% specificity, and 86.7% accuracy. Comparatively, the commercial extract yielded 70.8% sensitivity, 100% specificity, and 76.6% accuracy. CONCLUSIONS: SPT using in-house Coca-10% EtOH wheat extract yielded better accuracy than commercial extract for diagnosing immediate type wheat allergy in children.

Beta-Expansin of Bermuda, Johnson, and Para grass pollens, is a major cross-reactive allergen for Allergic Rhinitis patients in subtropical climate.

BACKGROUND: Subtropical grass pollens of Bermuda (BGP), Johnson (JGP), and Para or buffalo grass (PGP), are common causes of pollen allergies in warm climate area. Allergic rhinitis (AR) patients had positive skin prick test (SPT) to extract of these 3 grass pollens. However, no allergenic proteins of 3 grass pollens have never been studied. OBJECTIVE: To identify major allergens of BGP, JGP, and PGP in Thai grass pollen-allergic patients and to examine their sIgE cross-reactivity. METHODS: Serum of nine AR patients with positive SPT to at least 2 of 3 studied pollens were collected. Based on availability, only ImmunoCAP of BGP and JGP were available to determine a level of sIgE. Profiles of sIgE bound proteins from BGP, JGP, and PGP, were obtained by immunoblot. Major IgE bound protein was identified by liquid chromatography-tandem mass spectrophotometry (LC-MS/MS). Cross-reactivity of purified major allergen of the 3 grass pollens was determined by inhibition of sIgE in both ELISA and immunoblot. RESULTS: AR patients who have positive SPT to extract of BGP, JGP, and PGP, were 9, 8, and 6, respectively. Positive sIgE (> 0.35 kUA/L) to BGP and JGP were found in 9 and 8 patients, respectively. Eight profiles of IgE bound proteins of the 3 grass pollens showed 29-30 kDa pollen protein as major allergen and was identified as beta-expansin (ExpB). Moreover, purified ExpB of the 3 grass pollens cross-inhibited serum sIgE. CONCLUSION: ~30 kDa ExpB of BGP, JGP, and PGP, is major cross-reactive allergen for AR Thai patients.

Comparison of the efficacy and safety of pollen allergen extracts using skin prick testing and serum specific IgE as references.

BACKGROUND: Allergen extracts may be different due to the difference in dissemination of allergen-containing species in various geographical areas. Therefore, we wish to develop our own extracts to ensure the precision and quality of diagnosis. OBJECTIVES: To compare the efficacy and safety of our locally prepared pollen allergen extracts to imported ones, using skin prick testing (SPT) and serum specific IgE (sIgE) as references. METHODS: This prospective, randomized, double-blinded, self-controlled study was performed in respiratory allergic adult volunteers who are sensitized to at least one kind of pollen. Each subject was pricked with our Bermuda grass, Johnson grass and careless weed pollen allergen extracts, and also with the imported ones. sIgE levels were measured by using ImmunoCAP?. RESULTS: In 68 volunteers, our Bermuda, Johnson and careless weed extracts showed 91.2%, 45.6% and 54.4% positive SPTs, respectively, while for the imported ones 73.5%, 45.6% and 54.4% SPTs were positive, respectively. No adverse reaction was found in all procedures. The concentration of 10,000 BAU/mL of Bermuda grass, 1 : 20 w/v or 10,000 PNU/mL of Johnson grass and 1 : 40 w/v or 10,000 PNU/mL of careless weed yielded the most positive SPT results. There was no significant difference in mean wheal diameter (MWD) yielded from using local and imported extracts. Significant correlation was found between MWDs of imported pollen extracts and serum sIgE levels (p < 0.01). CONCLUSIONS: No significant difference between SPT results of local and imported pollen allergen extracts was found. Significant correlation was found between MWDs of imported pollen extract SPT and serum sIgE levels.

Identification of wheat sensitization using an in-house wheat extract in Coca-10% alcohol solution in children with wheat anaphylaxis.

BACKGROUND: Identification of wheat sensitization by a skin prick test (SPT) is essential for children with wheat-induced anaphylaxis, since oral food challenge can cause serious adverse effects. Wheat allergens are both water/salt and alcohol soluble. The preparation of wheat extract for SPT containing both water/salt and alcohol soluble allergen is needed. OBJECTIVE: To determine if a wheat extract using Coca's solution containing 10% alcohol (Coca-10% EtOH), prepared in-house, contians both water/salt and alcohol soluble allergens. METHODS: Serum of children with a history of anaphylaxis after wheat ingestion was used. Wheat flour was extracted in Coca-10% alcohol solution. An SPT with both commercial and in-house wheat extracts was performed as well as specific IgE (sIgE) for wheat and omega-5 gliadin. Direct and IgE inhibition immunoblots were performed to determine serum sIgE levels against water/salt as well as alcohol soluble (gliadins and glutenins) allergens in the extracts. RESULTS: Six children with history of wheat anaphylaxis had positive SPT to both commercial and in-house extracts. They also had different levels of sIgE against wheat and omega-5 gliadin allergens. The results of direct immunoblotting showed all tested sera had sIgE bound to ~35 kDa wheat protein. Further IgE inhibition immunoblotting identified the ~35 kDa wheat protein as gliadin but not gluten allergen. CONCLUSION: The in-house prepared Coca-10% EtOH solution could extract both water/salt and alcohol soluble allergens. The ~35 kDa gliadin appears to be a major wheat allergen among tested individuals.

Hypovitaminosis D in healthy children in Central Thailand: prevalence and risk factors.

BACKGROUND: There are limited data regarding the prevalence and risk factors relating to hypovitaminosis D in children of Thailand, a tropical country with abundant sunlight. The objective of this study was to assess the prevalence of hypovitaminosis D and examine factors associated with hypovitaminosis D in school-aged children in Bangkok, Thailand - a centrally located capital city. METHODS: This cross-sectional study evaluated 159 healthy children (33.3% boys and 66.7% girls), aged 6 to 12 years, in Bangkok, Thailand (located at 13.45°N). Fasting plasma samples were examined for total 25-hydroxyvitamin D [25(OH)D] using electrochemiluminescence immunoassay. Demographic characteristics (age, sex, household income), past medical history (birth weight, allergic diseases, hospitalization), amount of sun exposure, anthropometric data, and selected biochemical tests were used to investigate for factors associated with hypovitaminosis D. RESULTS: Overall, the mean ± SD level of plasma 25(OH)D was 64.0 ± 15.1 nmol/L. Hypovitaminosis D (< 75 nmol/L) was presented in 79.2% of subjects. Of these, the prevalence of vitamin D insufficiency and vitamin D deficiency were 59.7% and 19.5%, respectively. In univariate analysis, children with hypovitaminosis D (< 75 nmol/L) had a higher mean body mass index (BMI) percentile than the vitamin D-sufficient group (56.7 ± 33.9 vs. 42.6 ± 36.0; P-value = 0.04). Plasma PTH levels in the children with hypovitaminosis D were significantly higher than in the children with normal levels of vitamin D (4.34 ± 1.38 vs 3.78 ± 1.25 pmol/L; P-value = 0.04). In multivariate analysis, high BMI percentile and high PTH concentration were the parameters associated with 25(OH)D level < 75 nmol/L. CONCLUSION: The prevalence of hypovitaminosis D in healthy Thai children is very high, despite their exposure to sunlight, and that prevalence increases in children with a high BMI percentile. As a result, a formal recommendation for vitamin D supplementation in Thai children should be considered.

A combination of intravenous immunoglobulin and pulse methylprednisolone extended survival in pulmonary alveolar proteinosis with chronic interstitial pneumonitis: a case report.

Pulmonary alveolar proteinosis (PAP) is characterized by intra-alveolar accumulation of lipoproteinaceous material. The severe chronic pulmonary disease and susceptibility to pulmonary infection is a prominent feature of the disease. We reported a case of postnatal-onset PAP and chronic interstitial pneumonitis in a girl with chronic respiratory distress since she was 5 months of age. A lung biopsy confirmed the diagnosis. The therapeutic bronchoalveolar lavages, a short trial of granulocyte colony-stimulation factor (G-CSF) and a combination of low dose methylprednisolone and hydroxychloroquine were used at different times without noting satisfactory improvement. Intravenous immunoglobulin (IVIG) and pulse methylprednisolone were given monthly with gradual recovery. She did not require oxygen supplement after 21 months of this combination. Our report suggested that IVIG and pulse methylprednisolone might have a potential role in the treatment of PAP with chronic interstitial pneumonitis.

Diagnostic paradigm for evaluation of male patients with chronic granulomatous disease, based on the dihydrorhodamine 123 assay.

BACKGROUND: Chronic granulomatous disease (CGD) is a phagocyte disorder caused by mutations in nicotinamide dinucleotide phosphate (NADPH) oxidase subunits. The dihydrorhodamine 123 (DHR) assay is an effective test for CGD that for most patients also might help to differentiate between the 2 most common forms, X-linked (X) gp91(phox) defect CGD and autosomal recessive (AR) p47(phox) defect CGD. However, some male patients with X-CGD have DHR patterns that overlap the AR-CGD pattern. OBJECTIVE: The purpose of this investigation was to develop a diagnostic paradigm to delineate male patients with X-CGD expressing a DHR pattern suggestive of p47(phox) deficiency. METHODS: The DHR assay measured change in fluorescence of DHR-loaded granulocytes after phorbol myristate acetate (PMA) stimulation. Western blot analysis measured the presence of NADPH oxidase subunits gp91(phox), p47(phox), p67(phox), and p22(phox). CYBB exonic sequencing was performed on PCR-amplified genomic DNA through use of intronic flanking primers. Ferricytochrome-c assay evaluated specific superoxide production by PMA-stimulated granulocytes. RESULTS: Although 83% of patients with X-CGD have virtually no neutrophil DHR activity, we found that 17% of patients, proven to have X-CGD by other criteria, have modest DHR activity that is most consistent with p47(phox) deficiency. We describe a diagnostic paradigm to deal with such patients, and we present 2 cases, along with results of additional studies, including carrier evaluation, protein assessment, and mutation analysis, that are useful in establishing the genotype under these circumstances. DHR assays from the 2 patients described showed a fluorescence shift most characteristic of p47(phox)-AR-CGD; however, each of the patients' mothers showed mosaicism with a bimodal DHR pattern. Patient 1 had some gp91(phox) protein with a Y41D mutation and modest superoxide activity. Patient 2 had a normal level of gp91(phox) protein with a C537R mutation without detectable superoxide activity, as determined by ferricytochrome-c assay, despite the modest DHR activity. CONCLUSIONS: Evaluation of male patients with CGD with modest DHR activity should initially include evaluation of potential female carriers for mosaicism with the use of the DHR assay. In circumstances in which this is uninformative, patients should be referred to centers capable of additional testing, including Western blot analysis and CYBB mutation analysis, to clarify the disease genotype.