Epidemiology and economics of allergy treatment

The economic costs of severe anaphylaxis in France: an inquiry carried out by the Allergy Vigilance Network

BACKGROUND

The prevalence of severe anaphylaxis, between 1 and 3 per 10,000, has increased sharply over recent years, with a rate of lethality of 1%. The economic burden is unknown.

OBJECTIVE

The aim of this study was to estimate the economic costs of anaphylaxis, including direct costs of treatment, hospitalization, preventive and long-care measures, and the indirect cost: absenteeism.

METHODS

Analysis of 402 patients of anaphylaxis declared by 384 allergists was reported to the Allergy Vigilance Network. The global cost was estimated from the national data of hospital admissions: ICD-10 coding available for 2003, 2004 and 2005.

RESULTS

Three work/classroom days were lost per patient. Diagnosis required oral challenge with hospitalization in 18% of cases. The estimated mean total cost was 1895 euros for food- and drug-related anaphylaxis (5610 euros for the most severe), and 4053 euros for Hymenoptera anaphylaxis. National statistics recorded 2575 patients in 2005; 22% more than in 2003. The estimated annual cost was 4,789,500 euros. The possible reasons for this being an under-estimate include: data coming only from hospitalized patients, poor identification by medical teams unfamiliar with ICD-10 codes, peri-operative anaphylaxis being insufficiently declared, rush-immunotherapy and maintenance treatments for Hymenoptera anaphylaxis. Similarly, the extra cost of cow milk substitutes, as well as insurance costs where deaths are followed by litigation were not taken into account.

CONCLUSIONS

The mean cost of anaphylaxis was 1895-5610 euros in nonfatal patients. The prevalence was under-estimated because of many biases, leading to under-estimation of the national cost. Further studies would be necessary to evaluate the value of preventive strategies.

Profiling recombinant major birch pollen allergen Bet v 1a and carbamylated variants with CZE and CIEF

A preparation of recombinant birch pollen allergen of Betula verrucosa isoform 1a (Bet v 1a) containing chemically modified (carbamylated) variants has been analyzed by CZE and CIEF. In CZE, employing a 100 mmol/L MES buffer at pH 6.50, with 0.4 mmol/L tetraethylenepentamine (TEPA) added, allowed for the resolution of 17 protein fractions. The CIEF profiling of the allergen preparation required a combination of a wide-pH-range carrier ampholyte (CA) of pH 3-10 with two narrow-range CAs of pH 5-6 and 5-7. For CIEF, 91 mmol/L of glycine at pH 2.12 and 20 mmol/L of CHES at pH 10.00 were applied as anolyte and catholyte, respectively. The generated pH gradient was nonlinear with a flat slope for pH 4-6, thus providing an improved resolution. In CIEF, up to 18 protein fractions were distinguished as well. The pI of the target allergen Bet v 1a was 4.9 as determined by means of two pI marker compounds flanking the allergen. Relative purity of the target allergen within the preparation containing carbamylated variants was in accordance for both separation systems and varied between 40.7 and 42.8%.