Is mold sensitization associated with impaired pulmonary function in children with asthma

Background: Recent data indicate that sensitization to mold contributes to the severity and persistence of asthma. Aim: We aimed to investigate the relationships between sensitization to mold and lung function parameters in children with asthma. Methods: We reviewed clinical data from 551 children with asthma. They underwent spirometry, methacholine challenge tests, and measurements of blood eosinophils, IgE, ECP and FeNO levels. Skin prick testing (SPT) was performed with 13 common aeroallergens in Korea. Asthmatic children were divided into 3 groups according to their SPT results: Group 1, non-sensitized; Group 2, other allergen-sensitized; and Group 3, mold-sensitized. Results: Among the 551 asthmatic children, 67(15.5%) were sensitized to mold and 366 (84.5%) were sensitized to other aeroallergens. The log mean IgE levels were higher in Groups 2 (5.96±1.14 IU/mL) and 3 (5.81±0.97 IU/mL) compared to Group 1 (3.88±1.68 IU/mL). Blood eosinophils, ECP and FeNO were significantly higher in Groups 2 and 3 but no significant difference was found between the 2 groups. The mean FEV1 was significantly lower in Group 3 (86.9±12.1%pred) than in Groups 2 (92.0±14.8%pred) and 1 (93.4±15.4%pred). The log mean methacholine PC20 was significantly lower in Group 3 (0.08±1.91 mg/mL) than in Groups 2 (1.31±1.69 mg/mL) and 1 (2.29±1.66 mg/mL). Conclusions: We observed a differential association between mold and other aeroallergen sensitization, and severity of asthma. Sensitization to mold is associated with lower lung function and increased airway hyper-responsiveness in children with asthma. Mold sensitization could be an important factor determining asthma severity particularly airflow limitation in children.