CAP Class Research Articles

Reproducibility and seasonal dependence of specific intranasal provocation tests in birch pollen allergy patients

The intranasal allergen Provocation test (INT) is the standard procedure to verify the effect of an allergen when a nasal allergy is suspected. It may be especially useful if results from skin tests or in vitro tests conflict with those from the history. In the clinical and research setting, INT may be used to study the efficacy of different treatment modalities such as pharmacotherapy or immunotherapy. The technique of INT has not been well standardized in the past. Variations exist in planning the optimum time for testing, especially in seasonal allergies. We examined influences of different test dates with regard to the pollen season on the result of INT. A total of 19 patients (eight females, 11 males, aged 26.1 +/- 4.8 years) with a history of at least two years of allergic rhinitis to birch pollen, positive skin prick test, and RAST (> or = CAP class II) to birch pollen. INT was performed during the winter-period after approximately six months without natural pollen exposition (V1), during the birch pollen season (V2) and six weeks after the birch pollen season (V3). Allergens were applied using a pump spray (0.1 ml) in concentrations of 10, 50, 100, 500, 1000, 5000, 10,000, 50,000, and 100,000 SQ units per ml (SQ/ml). The threshold concentrations were significantly lower at V2 (100 SQ/ml) and V3 (500 SQ/ml) if compared to V1 (1000 SQ/ ml). Seasonal influences should be taken into account when performing INT in birch pollen allergy.

Comparison of modified PhadezymRAST,* ImmunoCAP,* and serial dilution titration skin testing by receiver operating curve analysis

Improved technology in in vitro tests for allergen-specific immunoglobulin E has led to increased efficiency and faster turnaround times. ImmunoCAP (Pharmacia Diagnostics, Clayton, N.C.) is an in vitro–specific immunoglobulin E test that uses a three-dimensional cellulose solid allergen phase, which allows quick results in 6 hours. In comparison, modified PhadezymRAST (Pharmacia Diagnostics) uses a two-dimensional solid phase, and results take 3 days to obtain. This study compares the sensitivity and specificity of CAP with that of modified RAST in the detection of specific immunoglobulin E, and it assesses the correlation of the individual class scores of CAP and modified RAST with end points obtained from skin-dilutional end-point titration. The reproducibility of CAP was also assessed. Patients evaluated at the University of Chicago Allergy Clinic who had a history and physical examination consistent with immunoglobulin E–mediated allergy and in whom skin testing was clinically indicated as part of their allergy management, were asked to donate some blood for simultaneous in vitro testing by PhadezymRAST and ImmunoCAP. Testing was performed in batches. Random samples from the CAP batches were chosen for duplicate runs under conditions blinded to the technician. Receiver operating curve analysis was used for comparison of the sensitivity and specificity of RAST vs. that of CAP. We used Pearson product-moment correlation coefficients to compare the correlation of RAST and CAP classes with the end points from skin testing. Our results indicate that the sensitivity and specificity of RAST and CAP are similar, that the classes of these two tests correlate well with the end points from skin testing, and that duplicate samples of CAP also correlate well. (OTOLARYNGOL HEAD NECK SURG 1995;112:665-9.)

On Uniformly Packed [n , n -k , 4] Codes over GF(q ) and a Class of Caps in PG(k -1, q )

On Uniformly Packed [<i>n</i> , <i>n</i> -<i>k</i> , 4] Codes over GF(<i>q</i> ) and a Class of Caps in PG(<i>k</i> -1, <i>q</i> )