Puncture Skin Test Research Articles

Angiomyomatous hamartoma of subglottic tracheal wall in a 12-year-old adolescent: a case report

BackgroundAllergic rhinitis is the most common allergic disease encountered in a primary care setting. Diagnosis is often made clinically based on response to empiric therapy. However, with long-term treatment failure and/or atypical disease presentation, a differential diagnosis should be considered. The following is a report of an unusual and rare presentation of a subglottic tracheal angiomyomatous hamartoma in an adolescent, treated for many years as allergic rhinoconjunctivitis and asthma.Case presentationA 12-year-old Caucasian was referred to the allergy clinic with a lifetime history of bronchospasms and rhinoconjunctivitis symptoms, treated for many years for asthma and environmental allergies. Cough, posterior nasal drainage, self-described “choking on phlegm,” and a sensation of “a flap in the throat,”, worsened 5 months prior to the initial evaluation. Puncture skin testing for common environmental allergens was negative. Spirometry, performed due to history of chronic cough, showed blunting of the forced expiratory phase. A chest X-ray, immediately ordered to rule out possible extrapulmonary obstruction, showed bilateral bibasilar infiltrates. A noncontrast computerized tomographic scan of the chest, ordered to further elucidate X-ray findings, revealed a subglottic tracheal mass. Following a subsequent transfer and admission to a tertiary hospital center, microlaryngoscopy, bronchoscopy, and microsuspension laryngoscopy were performed to remove the tracheal mass. Pathology confirmed squamous mucosa with polypoid angiomyomatous changes and chronic inflammatory features consistent with angiomyomatous hamartoma. Surgical intervention was successful, and follow-up 1 year postoperatively revealed a healthy, asymptomatic adolescent child with normal lung function.ConclusionsAlthough posterior nasal drainage and cough are typical presenting symptoms in the general patient population, they may be clinically impactful as they could disguise more serious medical conditions. A detailed history and careful physical examination may provide a high index of suspicion of disease, and can help work the differential diagnosis. This case presentation is the first documentation of subglottic hamartoma reported in the pediatric literature with clinical manifestation of environmental allergy and asthma symptoms.

Investigation of oral atopic diseases: Correlation between geographic tongue and fungiform papillary glossitis

IntroductionThe correlation between oral lesions and atopy is not new, but few studies have investigated the prevalence of mucosal changes in diseases within the atopic spectrum, leading to conflicting data. Some studies found a possible relationship between geographic tongue, transient lingual papillitis and atopic diseases. AimTo investigate the frequency of geographic tongue and fungiform papillary glossitis in patients with atopic diseases, and its correlation with serum IgE levels and skin test results. Material and methodsThe sample was comprised of participants with atopic diseases paired with participants who received negative puncture skin tests. All were submitted to stomatological and medical evaluations, prick test and oral cytopathological. ResultsThe female sex was more numerous in both groups. Mean age was 21 years. A total of 60 diagnoses of atopic diseases were obtained, with allergic rhinitis being the most prevalent. Fungiform papillary glossitis was the most frequent oral lesion in both groups, while geographic tongue was present in 2 cases (2%) in the test group and 2 (2%) in the control group. Atopic patients with fungiform papillary glossitis presented high serum IgE levels. In atopic patients with geographic tongue, the prick test positively identified extracts of Dermatophagoides pteronyssinus (100%) and Dermatophagoides farinae (100%). ConclusionDue to the low frequency of geographic tongue lesions found in the study, it is no possible to conclude if that could be an oral manifestation of atopy. However fungiform papillary glossitis is a common alteration in atopic and non-atopic patients and has a relationship with high IgE serum levels. However, the consolidation of this result requires a larger sample size.

Survey of Drug Allergy Testing, Challenge, and Desensitization Practice

Background: The lack of standardized skin test products to determine a patient’s (hyper-) sensitivity to medications has required physicians to empirically develop their own testing procedures. These approaches include puncture and intradermal skin tests, patch tests and medication challenges. Desensitization protocols are also frequently used when the necessity of a particular medication is urgent. Objective: This study surveyed drug hypersensitivity testing and desensitization practices reported in 3 allergy journals, over a 5-year period 2004-2008. Methods: This survey collected reports of skin tests, challenges, and desensitization to medications, vaccines, and diagnostic agents in 3 leading allergy journals. Studies were included if they reported sufficient detail that the reader could reasonably be expected to reproduce the technique reported. We did not include reports of in vitro testing because the ability of the individual practitioner to perform these tests may be limited. Results: Data for 191 drugs were sufficiently detailed to include. Testing with antimicrobial agents was reported most frequently; and several newer classes of medications such as monoclonal antibodies and interferons are also included. Skin testing to detect medication allergy was the most commonly reported technique; however there were numerous drug challenge and drug desensitization schedules used in practice. Conclusion: Beyond testing for medications such as antibiotics, corticosteroids and local anesthetics skin testing, challenge, and desensitization schedules have been described for numerous other medication classes. The variety of these schedules is likely driven both by the needs of clinical practice and the lack of standardized skin test preparations.

Cat allergen-induced blood basophil reactivity in vitro predicts acute human nasal allergen challenge responses in vivo

Basophil histamine release (BHR) to allergen has been used as a confirmatory test to support the clinical diagnosis of allergic disease. Among subjects reporting respiratory cat allergy, we hypothesized that cat-induced BHR in vitro would predict nasal allergen challenge (NAC) response in that same individual. We therefore compared the magnitude of cat allergen-induced BHR to NAC outcome and serological measures of cat-specific IgE and the ratio of cat-specific IgE to total IgE. Forty-two subjects with a history of cat allergy, positive cat puncture skin test (PST) and detectable cat-specific IgE (> 0.1 kAU/L, ImmunoCap) participated with consent. Subjects were grouped as positive or negative cat allergen-induced BHR, with a positive result defined as the release of ≥ 20% of the total cellular histamine content. The majority of subjects also underwent a NAC with a positive result defined as ≥ 5 total sneezes. Subjects with a positive compared with a negative cat allergen BHR had higher cat-specific IgE levels at 5.40 ± 1.24 kAU/L (n=25) vs. 1.55 ± 0.73 kAU/L (n=17, P=0.01) as well as a higher cat-specific IgE/total IgE ratio [6.1 ± 1.4% (n=25) vs. 1.6 ± 0.9% (n=17, P=0.01)]. Of the 31 subjects who underwent a NAC, a positive NAC was observed in 78% (18/23) with a positive cat allergen BHR compared with 37% (3/8) with a negative cat allergen BHR, giving a positive predictive value of 78% and a negative predictive value of 63%. The diagnostic sensitivity and specificity of a positive BHR to predict a positive NAC was 86% and 50%, respectively. A positive cat allergen-induced BHR is associated with higher cat-specific IgE levels, a higher cat-specific to total IgE ratio and is predictive of a positive cat-induced NAC [ClinicalTrials.gov NCT00604786].

Is puncture skin test adequate to detect autoreactivity in patients with chronic urticaria?

Is puncture skin test adequate to detect autoreactivity in patients with chronic urticaria?

Prick puncture skin tests and serum specific IgE as predictors of nasal challenge response to Dermatophagoides pteronyssinus in older adults

The ability of prick puncture skin test (PPST) results and the presence of serum specific IgE (sIgE) to Dermatophagoides pteronyssinus to predict positive or negative nasal challenge (NC) results has not been determined in older adults. To determine if allergy skin test and/or serum sIgE is diagnostic of allergic rhinitis in older adults. Forty-eight adults (20 younger and 28 older) with rhinitis underwent NC to D. pteronyssinus 1 to 4 weeks after PPST and sIgE to D. pteronyssinus. Patients were not aware of their in vivo or in vitro results at the time of their NC. Fourteen of 48 adults (10 younger and 4 older) were NC positive. The positive predictive values for older adults with positive NC results ranged from 28.57% to 42.86% for PPST and was 16.67% for sIgE. In contrast, positive predictive values in younger adults ranged from 76.92% to 100% for PPST and was 100% for sIgE. However, negative PPST results and sIgE had high predictive values for a negative NC result to D. pteronyssinus in older adults (90.48%-95.24% for PPST and 89.47% for sIgE). Although PPST and sIgE negative results were good predictors of negative NC outcomes, neither positive PPST results nor serum sIgE to D. pteronyssinus predicted positive NC results in older adults. PPST and sIgE to D. pteronyssinus were excellent predictors of both positive and negative NC outcomes in younger adults.

Long-term Immunologic Effects of Broad-Spectrum Aeroallergen Immunotherapy

Limb SL, Brown KC, Wood RA, Eggleston PA, Hamilton RG, Adkinson NF Jr. Int Arch Allergy Immunol. 2006;140:245–251 PURPOSE OF THE STUDY. To evaluate the long-term clinical effects, skin tests, and specific immunoglobulin E (IgE) levels from subjects who had previously received broad-spectrum aeroallergen immunotherapy several years earlier. STUDY POPULATION. Eighty-two polysensitized subjects who had previously been enrolled onto a randomized, double-blind, placebo-controlled trial of specific immunotherapy for treatment of childhood allergic asthma METHODS. Eighty-two subjects (78% male; mean age: 23 years) previously enrolled onto a randomized, placebo-controlled trial of immunotherapy for the treatment of childhood allergic asthma were reevaluated in adulthood (mean follow-up interval: 10.8 years) by puncture skin tests and CAP-RAST levels for major aeroallergens. All subjects originally completed at least 18 months (median: 27 months) of maintenance active immunotherapy treatment or placebo injections without subsequent immunotherapy. RESULTS. At adult follow-up, 36% of all skin tests to treatment allergens among subjects who received immunotherapy (n = 41) had significantly reduced intensity versus 26% of skin tests among placebo recipients (n = 41; P = .03). No significant differences were noted for individual treatment allergens. No significant differences were observed in the long-term changes of serum-specific IgE antibody levels for all or individual treatment allergens between immunotherapy treatment and placebo groups (P = .43). The treatment and placebo groups had a similar acquisition of new skin-test sensitivities from time of randomization in the original childhood trial to debriefing (15% vs 20%; P = .28) and to adult follow-up (30% vs 31%; P = .75). CONCLUSIONS. Immunotherapy suppresses skin-test sensitivity 8 to 16 years after discontinuation of treatment, but long-term effects on specific IgE levels in serum are not observed. Broad-spectrum immunotherapy does not seem to affect the acquisition of new inhalant sensitivities. REVIEWER COMMENTS. In this study, allergic-asthmatic children who participated in a double-blind, placebo-controlled immunotherapy trial were reevaluated as adults to determine if immunotherapy had long-lasting effects. This study revealed that asthmatic children who received immunotherapy to multiple allergens for a median of 27 months had limited long-term effects on the results of testing parameters routinely used in allergy practice. The long-term efficacy of immunotherapy and optimal duration of therapy are issues that remain open.

Autoimmune urticaria at 3 years of age diagnosed by puncture skin test using autologous serum

Autoimmune urticaria at 3 years of age diagnosed by puncture skin test using autologous serum

Comparision of Compositional Differences and Relative Potency Between Different Manufacturers of Ragweed Pollen Extracts

RATIONALE: Ragweed extract (RWE) manufacturers must meet rigorous FDA standards and any change in producers must not negatively impact relative potency (RP) of the product. We evaluated the compositional differences (CD) and RP of an investigational RWE prepared by Lonza (LZ) [Visp: 198u Amb a 1] for Curalogic (Copenhagen) to the RWE [Hollister-Stier (HST): 259u] used in their prior US studies. METHODS: Serial endpoint titration [parallel-line bioassay method] was utilized to assess RP of the two test products which were also contrasted to a licensed (reference) US RWE [Greer (197u Amb a 1)]. Linear regression modeling calculated the best-fit (least squares) straight line for each assay [4-point ID titration (ΣE=50 mm)]. RESULTS: 8 subjects completed the study [mean age: 40; range: 30-57); mn RW puncture skin test sensitivity (ΣE): 80mm (med: 82.5; range: 45-100). Six subjects had valid assays [correlation of coefficient (R): ≥0.92; slope: ≥13mm]. CD (measured by standard deviation of the mn log3 RP): 0.595 [CDER upper limit: 0.68] demonstrated the LZ RWE was not different from the comparator (HST). The LZ RWE RP was 85% of the comparator [mn log3 RP: -0.4; SD: 0.595], thus the 2 RWE can be considered equal in potency [reference %: 71-141]. The LZ and HST RWE potencies were 127 and 171% of the non-dialyzed reference RWE. CONCLUSIONS: The CD and RP of RWE manufactured by LZ was demonstrated to be compositionally similar and equal in potency to its comparator RWE and highlights the importance of dialyzing the allergen in the manufacture of the product.

Latex specific IgE: performance characteristics of the IMMULITE 2000 3gAllergy assay compared with skin testing

In the absence of a US Food and Drug Administration (FDA)-cleared latex skin testing reagent, in vitro tests remain important for the diagnosis of latex allergy. To evaluate the performance characteristics of IMMULITE 2000 3gAllergy (Immulite), a third-generation, FDA-cleared, continuous random-access immunoanalyzer, for the quantification of latex specific IgE. Stored serum samples (N = 201) from patients classified as having positive or negative latex puncture skin test results were measured for latex specific IgE levels using Immulite, and these data were compared with historical results from 3 second-generation, FDA-cleared IgE antilatex assays (AlaSTAT [Ala], AutoCAP [CAP], and HY*TEC enzyme immunoassay [HT]). The diagnostic performances of the CAP, Ala, and Immulite assays (> or = 0.35 kU/L cutoff value) were equivalent in sensitivity and specificity (P > .05). The HT assay (> or = 0.05 kU/L cutoff value) was more sensitive and less specific (P < .05). Immulite (> or = 0.10 kU/L cutoff value) had greater sensitivity than Ala and CAP and greater specificity than HT (P < .05 for both). Diagnostic efficiency was greater for Immulite than for CAP, Ala, and HT (P < .05). The Immulite system is superior in diagnostic performance, especially at the 0.10 kU/L or greater cutoff level, for the diagnosis of latex allergy compared with older, second-generation assays. Immulite still misclassifies 15.5% of puncture skin test-positive individuals as negative for latex specific IgE. Compared with second-generation assays, Immulite represents a technological advance, with enhanced speed and less operator intervention.

Long-Term Immunologic Effects of Broad-Spectrum Aeroallergen Immunotherapy

Background: Limited data exist regarding extended, long-term immunologic effects of immunotherapy in polysensitized individuals. To study possible long-term effects, skin tests and specific IgE levels were obtained from subjects who had previously received broad-spectrum aeroallergen immunotherapy years before. Methods: Eighty-two subjects (78% male, mean age 23 years) previously enrolled in a randomized, placebo-controlled trial of immunotherapy for treatment of childhood allergic asthma were reevaluated in adulthood (mean follow-up interval, 10.8 years) by puncture skin tests and CAP-RAST levels for major aeroallergens. All completed at least 18 months (median 27 months) of maintenance active treatment or placebo injections without subsequent immunotherapy. Results: At adult follow-up, 36% of all skin tests to treatment allergens among subjects who received immunotherapy (n = 41) had significantly reduced intensity versus 26% of skin tests among placebo recipients (n = 41; p = 0.03). No significant differences were noted for individual treatment allergens. No significant differences were observed in the long-term changes of serum-specific IgE antibody levels for all treatment allergens between immunotherapy treatment and placebo groups (p = 0.43). The treatment and placebo groups had a similar acquisition of new skin test sensitivities from time of randomization in the original childhood trial to debriefing (15 vs. 20%; p = 0.28) and to adult follow-up (30 vs. 31%; p = 0.75). Conclusions: Immunotherapy suppresses skin test sensitivity 8–16 years after discontinuation of treatment, but long-term effects on specific IgE levels in serum are not observed. Broad-spectrum immunotherapy does not appear to affect the acquisition of new inhalant sensitivities.

Strict Avoidance of Exposure to Natural Rubber Latex (NRL) Glove Products is Associated with Longitudinal Reduction in Percutaneous Reactivity to NAL and Hev B Proteins

RATIONALE: Longitudinal effects of avoidance of powdered NRL glove exposure on puncture skin test (PST) reactivity to non-ammoniated latex (NAL) and purified native allergens (Hev b) have not been assessed.

EFFECT OF MATTRESS AND PILLOW ENCASINGS ON CHILDREN WITH ASTHMA AND HOUSE DUST MITE ALLERGY

Halken S, Host A, Niklassen U, et al. J Allergy Clin Immunol. 2003;111:169–176 Allergy to house dust mite (HDM) is an important contributor to childhood asthma, and these investigators sought to determine whether the use of mattress and pillow encasings resulted in effective long-term control of mattress HDM levels, thus reducing the need for maintenance asthma medication. The subjects were 60 children (5–15 years of age) with asthma and HDM allergy, in the absence of any other clinically relevant allergy. Inclusion criteria included physician-diagnosed asthma, positive HDM puncture skin test results, positive …

EFFECT OF MATTRESS AND PILLOW ENCASINGS ON CHILDREN WITH ASTHMA AND HOUSE DUST MITE ALLERGY

Halken S, Host A, Niklassen U, et al. J Allergy Clin Immunol. 2003;111:169–176Allergy to house dust mite (HDM) is an important contributor to childhood asthma, and these investigators sought to determine whether the use of mattress and pillow encasings resulted in effective long-term control of mattress HDM levels, thus reducing the need for maintenance asthma medication.The subjects were 60 children (5–15 years of age) with asthma and HDM allergy, in the absence of any other clinically relevant allergy. Inclusion criteria included physician-diagnosed asthma, positive HDM puncture skin test results, positive HDM bronchoprovocation results, and total HDM concentrations of ≥2000 ng/g dust from the child’s mattress. All except 4 of the study patients were treated with inhaled corticosteroids.In this prospective, double-blind, placebo-controlled, 1-year study, children were randomized to the use of active (allergy control) or placebo mattress and pillow encasings. Baseline measures included mattress dust sampling, spirometry, and adjustment of medications. Symptom scores and peak flows were recorded throughout the study. Clinical assessments, including medication adjustments, and dust sampling were performed every 3 months. Bronchoprovocation was performed at the time of inclusion and at completion of the study.Twenty-six children in the active treatment group and 21 children in the placebo group completed the study. A significant perennial reduction in levels of HDM allergen recovered from mattresses was noted only for the active treatment group. Significant decreases in the doses of inhaled corticosteroids also were noted only for the active treatment group. There were no significant differences between the active treatment and placebo groups in any of the secondary endpoints, including peak flow and forced expiratory volume in 1 second, symptoms, and HDM bronchoprovocation results.The use of mattress and pillow encasings led to significant long-term reductions in HDM allergen levels in mattresses and in the need for inhaled corticosteroids among children with asthma and HDM allergy.Greater HDM allergen exposure in childhood is associated with more severe asthma. However, it has been difficult to demonstrate in clinical studies that HDM avoidance is both achievable and associated with subsequent clinical improvement. This is not surprising, given the ubiquitous nature of HDMs and concomitant exposure to other contributing allergens. These authors chose their patient population carefully, to allow greater focus on the allergens in question. The 1-time cost of these encasings is approximately equal to the cost of 1 month of asthma drug therapy in the United States, and encasings are labor- and risk-free. They should be made available to HDM-allergic persons of all ages unless there is compelling evidence against them, which there is not currently. The same cannot be said for measures such as duct cleaning and the use of special filters, which likely have very little effect on either the ambient load of HDM allergen or clinical status.

Diminished dendritic cell interleukin 10 production in atopic children

Diminished interleukin 10 (IL-10) and/or IL-12 production may contribute to the pathogenesis of asthma and atopy. Dendritic cells (DCs) produce these cytokines and have been implicated in the pathogenesis of these disorders. To determine whether DC IL-10 and/or IL-12 production is diminished in children aged 6 to 12 years with allergic rhinitis (AR) and with or without asthma. Monocyte-derived DCs were isolated from 20 subjects without AR or asthma (group 1), 20 subjects with AR without asthma (group 2), and 20 subjects with AR and asthma (group 3). Asthma was defined as a history of physician-diagnosed disease, and AR was defined as a positive history and positive puncture skin test responses (wheal > or = 5 mm) to relevant inhalant allergens. DCs were stimulated with either lipopolysaccharide (LPS) or diluent and cultured for 24 hours. Supernatants were assayed for IL-10 and IL-12 levels by enzyme-linked immunosorbent assay. DC IL-10 production was diminished in groups 2 and 3 compared with group 1. Median LPS-induced IL-10 levels were 11.0 pg/mL in group 1, 6.1 pg/mL in group 2, and 1.5 pg/mL in group 3. The frequencies of subjects with detectable IL-10 levels were 85%, 20%, and 20% in groups 1, 2 and 3, respectively. Median LPS-induced IL-12 levels were similar in all groups. These data support the hypothesis that atopic subjects have an intrinsic inability to up-regulate DC IL-10 production. Future studies in this area could lead to a better understanding of the pathogenesis of atopy.

Comparison of Subject-Reported Allergy versus Skin Test Results in a Common Cold Trial

Few studies have examined the relationship between subject-reported allergy and results of allergy skin testing in large unselected or unbiased cohorts. The objective of this study was to compare the results of self-reported allergy via verbal questioning with the results of allergy skin testing by the puncture method in 237 healthy adult subjects enrolled in a common cold study. On enrollment, all subjects were verbally asked if they had a history of allergy and then underwent puncture skin testing to 19 relevant aeroallergens, as well as appropriate positive and negative controls. A skin test was considered positive if its wheal diameter was at least 3 mm larger than that obtained with the negative control. Forty-eight (20%) subjects reported a history of allergy and 124 (52%) subjects had at least one positive skin test response. A history of allergy was reported in 40 (32%) of the skin test-positive subjects and 8 (7%) of the skin test-negative subjects. At least one positive skin test response was found in 40 (83%) of those subjects reporting a history of allergy and 84 (44%) of those subjects denying a history of allergy. These data indicate that there is a relatively poor correlation between self-reported history of allergy and skin test results in subjects enrolled in a common cold study. These results have implications in both clinical practice and research settings.

Allergen prick-puncture skin testing in the elderly.

Many older patients present with rhinitis, conjunctivitis, asthma or itching that the patient attributes to allergies. Yet physicians often dismiss allergy in the elderly as irrelevant. Testing elderly patients for allergies is sometimes challenging as changes in the skin may cause difficulty in applying skin tests, and the response of the skin may be difficult to measure. The prick puncture skin test is the preferred method of immediate-type allergy testing, but careful examination of the skin prior to skin testing is important. If the area of skin where allergen skin tests are routinely placed is either atrophic or severely sun damaged, a sun-protected area should be sought. If no suitable area of skin can be identified, in vitro allergen testing should be considered. Skin-test results must be interpreted with care in the elderly. Positive skin tests to an allergen must correlate with a history of exacerbation to the allergen. By identifying specific allergens to which the elderly patient is sensitive, avoidance measures or specific allergen vaccination can be recommended, improving the quality of life and decreasing the need for medications.

Diagnostic sensitivity of puncture skin testing (PST) with isolated native and recombinant proteins from Hevea brasiliensis (Hev b) for the diagnosis of latex hypersensitivity in healthcare workers (HCWs)

Diagnostic sensitivity of puncture skin testing (PST) with isolated native and recombinant proteins from Hevea brasiliensis (Hev b) for the diagnosis of latex hypersensitivity in healthcare workers (HCWs)

Receiver operating characteristics analyses of Food and Drug Administration-cleared serological assays for natural rubber latex-specific immunoglobulin E antibody.

Receiver operating characteristics (ROC) analyses to evaluate and compare the diagnostic accuracy of Food and Drug Administration (510K)-cleared natural rubber latex (NRL)-specific immunoglobulin E (IgE) antibody immunoassays have not been performed using well-characterized skin-testing reagents. Sera were collected from 311 subjects (131 latex puncture skin test [PST] positive and 180 PST negative). All masked, coded sera were analyzed for latex-specific IgE antibodies in the Diagnostic Products Corporation microplate AlaSTAT, HYCOR HY-TEC RAST, and Pharmacia-Upjohn CAP System RAST FEIA (CAP). Diagnostic accuracy was evaluated using GraphRoc for Windows software to construct and analyze ROC curves in relation to the subjects' PST status and the results of the immunoassays. The ROC areas under the curve (AUCs) +/- standard error based on PST for the three diagnostic tests were 0.858 +/- 0.024, 0.869 +/- 0.024, and 0.924 +/- 0.017, respectively, for AlaSTAT, CAP, and HY-TEC. The HY-TEC system had a significantly greater AUC based on PST than those observed for AlaSTAT (P < 0.05) and CAP (P < 0.05) analyses. When the diagnostic tests were probed as to the cutoffs giving maximal diagnostic efficiency compared to PST, CAP and AlaSTAT yielded values of <0.35 kU of allergen IgE (kU(A))/liter and <0.35 kU/liter while the HY-TEC assay yielded 0.11 kU/liter. The diagnostic efficiencies based on PST in our cohort at these cutoffs were 87.1, 88.1, and 88.7%, respectively. The HY-TEC assay had a significantly greater AUC than CAP and AlaSTAT using PST as a diagnostic discriminator in our cohort. When the HY-TEC system was probed at its maximally efficient cutoff (0.11 kU/liter) versus HYCOR's recommended cutoff of 0.05 kU/liter, a loss of sensitivity of 8.4% was observed with a gain in specificity of 19.5%.

Repeated latex aeroallergen challenges employing a hooded exposure chamber: safety and reproducibility.

Bronchial, nasal, and conjunctival challenges are useful for clarifying discordant clinical history (Hx) and skin and/or serologic tests and in assessing semiquantitative changes in biologic sensitivity over time. The objective of this study was to determine the safety and reproducibility of repeated latex-allergen challenges with a hooded exposure chamber (HEC). The HEC system comprises a powered forced-air respirator with a fitted face shield and hood that uses glove-derived latex-allergen associated cornstarch particles (LAC) to expose simultaneously the conjunctiva, nose, and lungs. Serial control and incremental LAC challenges are conducted until an endpoint based on upper and/or lower respiratory tract symptoms and peak expiratory flow rates is reached. Six latex-allergic (Hx and puncture skin test [PST]- and 5/6 radioallergosorbent test [RAST]-positive) subjects were challenged on three separate occasions at least 2 weeks apart. Serial latex PST midpoints and serum anti-latex IgE by RAST were monitored at each visit and at a fourth follow-up visit. All subjects responded to LAC, but not to air or control cornstarch administered as controls. All responses were confined to mild symptoms of allergic rhinoconjunctivitis and/or asthma that either resolved spontaneously or were reversed with inhaled albuterol. No subject experienced a systemic or delayed reaction. There were no significant changes in the endpoint LAC doses over the three challenge visits (P>0.2). The mean coefficient of variation for log2 endpoints within-subjects was 17.3+/-17.2% (SD). The serum latex-specific IgE was not significantly boosted by the three challenges (P>0.2). The concentration of latex extract necessary to produce an 8-mm wheal by PST was not significantly changed during the study (P>0.1), indicating that latex sensitivity was not affected by the repeated LAC exposures. The results of this study indicate that repeated HEC latex-allergen challenges are both reproducible and safe, and do not increase latex sensitivity.