Évolution des épreuves fonctionnelles respiratoires (EFR) chez des enfants atteints de mucoviscidose et dépistés à la naissance. Lien avec l'infection pulmonaire. Étude sur 40 enfants et 744 EFR

Aspergillus sensitization or carriage in cystic fibrosis patients

BACKGROUND

Aspergillus fumigatus (Af) sensitization and persistent carriage are deleterious to lung function, but no consensus has been reached defining these medical entities. This work aimed to identify possible predictive factors for patients who become sensitized to Af, compared with a control group of non-sensitized Af carriers.

METHODS

Between 1995 and 2007, 117 pediatric patients were evaluated. Demographic data, CFTR gene mutations, body mass index and FEV1 were recorded. The presence of Af in sputum, the levels of Af-precipitin, total IgE (t-IgE) and specific IgE to Af (Af-IgE) were determined. Patients were divided into 2 groups: (1) "sensitization": level of Af-IgE > 0.35 IU/mL with t-IgE level < 500 IU/mL and (2) "persistent or transient carriage": Af-IgE level ≤ 0.35 IU/mL with either an Af transient or persistent positive culture. A survival analysis was performed with the appearance of Af-IgE in serum as an outcome variable.

RESULTS

Severe mutation (hazard ratio = 3.2), FEV1 baseline over 70% of theoretical value (hazard ratio = 4.9), absence of Pa colonization, catalase activity and previous azithromycin administration (hazard ratio = 9.8, 4.1 and 1.9, respectively) were predictive factors for sensitization. We propose a timeline of the biological events and a tree diagram for risk calculation.

CONCLUSIONS

Two profiles of cystic fibrosis patients can be envisaged: (1) patients with nonsevere mutation but low FEV1 baselines are becoming colonized with Af or (2) patients with high FEV1 baselines who present with severe mutation are more susceptible to the Af sensitization and then to the presentation of an allergic bronchopulmonary aspergillosis event.

Assessment of Aspergillus sensitization or persistent carriage as a factor in lung function impairment in cystic fibrosis patients

BACKGROUND

Cystic fibrosis (CF) patients presenting with persistent carriage of, or sensitization to, Aspergillus fumigatus are often treated with antifungal therapies because the presence of the fungus is commonly thought to impede lung function, even in the absence of allergic bronchopulmonary aspergillosis (ABPA). The aim of this study was to assess Aspergillus-related status modulating the forced expiratory volume in 1 s (FEV₁) of CF patients.

METHODS

From 1995 to 2007, 251 patients were evaluated. Demographic data, cystic fibrosis transmembrane conductance regulator gene (CFTR) mutations, body mass index, and FEV(1) were recorded. The presence of A. fumigatus and Pseudomonas aeruginosa in sputum and the levels of A. fumigatus precipitin, total IgE (t-IgE), and specific anti-A. fumigatus IgE (Af-IgE) were determined. Patients were divided into 3 groups: (1) ABPA: A. fumigatus precipitin ≥3 lines, Af-IgE > 0.35 IU/ml, and t-IgE ≥500 IU/ml; (2) sensitization: Af-IgE > 0.35 IU/ml but t-IgE < 500 IU/ml; and (3) persistent carriage: Af-IgE ≤ 0.35 IU/ml with either an A. fumigatus persistent positive culture or an A. fumigatus precipitin ≥3 lines, provided this serological finding had been found associated with at least 1 A. fumigatus-positive culture. The remaining patients represented the control group. A multivariate analysis was carried out with FEV(1) as the outcome variable.

RESULTS

ABPA, sensitization, and persistent carriage were significantly associated with a larger decline in FEV₁ compared with the control group, with odds ratios of 15.9, 14.9, and 10.7, respectively. This association was independent of other associated factors (P. aeruginosa transient detection, age, being underweight, and low FEV₁ at baseline).

CONCLUSIONS

In addition to ABPA, sensitization and persistent carriage appear to have an impact on pulmonary function in CF patients.