METHODS: A cross-sectional diagnostic study was performed on patients who had undergone nasal endoscopy and allergy testing. Allergy status was determined by positive serology or epicutaneous testing. Endoscopy was reviewed by blinded assessors for middle turbinate head edema. Appearance was graded as either normal, focal, multifocal, diffuse, or polypoid edema. Receiver-operator (ROC) analysis, likelihood ratio (LR), sensitivity, specificity, and positive predictive value (PPV) were determined.
RESULTS: One hundred eighty-seven patients representing 304 nasal cavities were assessed (42% female, age 39.74 ± 14.7 years, 57% allergic). Diffuse edema (PPV 91.7%/LR = 8) and polypoid edema (PPV 88.9%/LR = 6.2) demonstrated the strongest association with inhalant allergy. Multifocal edema was used as a cut-off to represent inhalant allergy from ROC analysis, which demonstrated 94.7% specificity and 23.4% sensitivity. The PPV for multifocal was 85.1% and LR = 4.4.
CONCLUSION: Middle turbinate edema is a useful nasal endoscopic feature to predict presence of inhalant allergy and, although not sensitive, has excellent PPV.
OBJECTIVE: The present study aimed to measure the agreement between BAT and immunoassay in diagnosis of penicillin allergy.
METHOD: BAT was performed using penicillin G (Pen G), penicillin V (Pen V), penicilloyl-polylysine (PPL), minor determinant mix (MDM), amoxicillin (Amx) and ampicillin (Amp) in 25 patients. Immunoassay of total IgE (tIgE) and specific IgE (sIgE) antibodies to Pen G, Pen V, Amx and Amp were quantified. Skin prick test (SPT) using PPL-MDM, Amx, Amp and Clavulanic acid were also performed.
RESULTS: Minimal agreement was observed between BAT and immunoassay (k=0.25). Of two BAT-positive patients, one patient is positive to Amx (59.27%, SI=59) and Amp (82.32%, SI=82) but sIgE-negative to all drug tested. This patient is also SPT-positive to both drugs. Another patient is BAT-positive to Pen G (10.18%, SI=40), Pen V (25.07%, SI=100) and Amp (19.52%, SI=79). In sIgE immunoassay, four patients were sIgE-positive to at least one of the drugs tested. The sIgE level of three patients was between low and moderate and they were BAT-negative. One BAT-positive patient had a high level of sIgE antibodies (3.50-17.5kU/L) along with relatively high specific to total IgE ratio ≥0.002 (0.004-0.007).
CONCLUSIONS: The agreement between BAT and immunoassay is minimal. Performing both tests provides little increase in the sensitivity of allergy diagnosis work-up for immediate reactions to penicillin.
OBJECTIVE: We conducted a phase 1/2 clinical study to examine the safety and diagnostic accuracy (sensitivity and specificity) of nonammoniated latex, ammoniated latex, and rubber glove extracts as skin test extracts to identify the most efficacious source material for future skin test reagent development.
METHODS: Twenty-four adults not allergic to latex, 19 adults with hand dermatitis or pruritus, and 59 adults with a latex allergy were identified by clinical history. All provided blood and then received puncture skin tests and intradermal skin tests with nonammoniated latex, ammoniated latex, and rubber glove extracts from Malaysian H. brasiliensis latex by use of sequential titration. A glove provocation test and IgE anti-latex RAST were used to clarify positive history-negative skin test response and negative history-positive skin test response mismatches.
RESULTS: All three extracts were biologically safe and sterile. After normalization to 1 mg/ml of total protein, all three extracts produced equivalent diagnostic sensitivity and specificity in puncture skin tests and intradermal skin tests at various extract concentrations. Optimal diagnostic accuracy was safely achieved at 100 micrograms/ml for intradermal skin tests (e.g., nonammoniated latex: puncture skin test sensitivity 96%, specificity 100%; intradermal skin test sensitivity 93%, specificity 96%). The presence of IgE antibody in skin was highly correlated with IgE anti-latex in serum (nonammoniated latex: r = 0.98, p < 0.001; ammoniated latex: r = 0.94, p < 0.001; rubber glove extract: r = 0.96, p < 0.001). All five available subjects with a positive history, negative skin test response, and absence of IgE antibody in serum had a negative glove provocation test response, indicating no clinical evidence of latex allergy. No systemic or large local allergic reactions were observed with puncture skin tests or intradermal skin tests.
CONCLUSIONS: Equivalent diagnostic sensitivity and specificity were observed with the nonammoniated latex, ammoniated latex, and rubber glove extract skin test reagents after normalization for total protein; nonammoniated latex may be considered the reagent of choice on the basis of practical quality control and reproducibility considerations.
OBJECTIVES: We aim to determine relevant seafood sensitization among adults with AD and investigate cross-sensitization to aeroallergens.
METHODS: One hundred thirty-two adults with AD who were subjected to skin prick test (SPT) with 7 common local seafood allergens (anchovy, tuna, mackerel, squid, giant freshwater prawn, shrimp, and crab), house dust mites (HDMs), and cockroach were analyzed retrospectively.
RESULTS: The median age of the study subjects was 32 years (range 17-77 years) with a male to female ratio of 1:3. The mean duration of AD was 16 years. Eighty-two patients (62.2%) had other atopic conditions. Using SCORAD, 44.7% had mild, 42.4% moderate, and 12.9% severe disease. Eighty-six patients (65.2%) self-reported to have seafood allergy, with the main symptoms of transient pruritus and erythema within 2 h of ingestion. SPT revealed 51.5% of the patients were sensitized to at least 1 of the 7 seafood allergens. The relevant sensitization rate was 45.1%. Interestingly, 46% of those without a history of seafood allergy developed at least 1 positive reaction in the SPT. Prawn, shrimp, and crab were the 3 most frequently sensitized allergens. Nearly all patients (98.3%) who were sensitized to crustaceans were also sensitized to HDMs and/or cockroach. There was no significant correlation between a positive SPT to seafood with age, age of onset of AD, duration, and severity of AD, and the presence of other atopic diatheses.
CONCLUSION: The relevant sensitization rate of local seafood among adults with AD was 45.1%.
OBJECTIVES: The objective of this study was to evaluate the effects of allergen sensitization and family history of atopy on asthma and allergic disease in Chinese schoolchildren from three southeast Asian populations.
METHODS: Written questionnaires on respiratory and allergic symptoms were completed by parents of children of secondary-school age (age range 12 to 18 years) in Hong Kong (n = 1062), Kota Kinabalu in eastern Malaysia (n = 409), and San Bu in southern China (n = 737). A subsample of school-children underwent skin prick testing to common inhalant allergens (Hong Kong 471 children, Kota Kinabalu 321, San Bu 647).
RESULTS: The prevalence of asthma and allergic disease in schoolchildren was highest in Hong Kong, intermediate in Kota Kinabalu, and lowest in San Bu. However, the overall rate of atopic sensitization was similar in the three populations (49% to 63%). House dust mite and cockroach were the two most common allergens causing sensitization and these gave rise to more than 95% of the positive skin test results in all three populations. By regression analysis, mite allergy was associated with rhinitis and asthma in all three populations, and a family history of asthma, rhinitis, or eczema was strongly associated with respective symptoms in the subjects. After adjusting for age, sex, atopic status, and family history of allergic disease, the place of residence remained a significant independent factor for asthma (odds ratio [OR] = 1.0 for Hong Kong, 0.57 for Kota Kinabalu, 0.15 for San Bu, p < 0.001), rhinitis (OR = 1.0 for Hong Kong, 0.59 for Kota Kinabalu, 0.15 for San Bu, p < 0.001), or eczema (OR = 1.0 for Hong Kong, 0.35 for Kota Kinabalu, 1.01 for San Bu, p < 0.001).
CONCLUSION: Sensitization to indoor allergens was a significant risk factor for asthma and allergic disease, and familial clustering of disease was common in the region. However, the marked difference in disease prevalence in the three southeast Asian populations of Chinese schoolchildren cannot be explained by atopic sensitization and family history alone, and the place of residence was an independent risk factor for asthma and allergies, which suggests an important environmental role in disease pathogenesis.