Background: There is no measure currently available to identify asthmatics with potential immune incompetence.
Objective: We propose use of a novel scoring system called the FACT score, which is formulated based on four parameters: (1) Family history of asthma, (2) Atopic conditions, (3) Bacterial colonization and (4) Th1 versus Th2 immune profile.
Methods: This was a cross-sectional study involving 16 asthmatics and 14 non-asthmatics. The first two parameters of the FACT score were obtained via a chart review and interview. For the third parameter, nasopharyngeal swab samples were cultured. The ratio of interleukin-5 to interferon-gamma for each patient was measured by peripheral blood mononuclear cells cultured with house dust mite. Antibodies to 23 pneumococcal antigens were used for humoral immunity.
Results: The FACT scores for asthmatics (mean ± SD: 5.2 ± 1.87) were higher than those for non-asthmatics (mean ± SD: 3.3 ± 1.5) (p = 0.008). Of the 16 asthmatics, 7 (44%) had 12 or more positive serotype-specific polysaccharide antibodies, whereas 12 of 14 (86%) of non-asthmatics subjects had 12 or more positive serotype-specific polysaccharide antibodies (p = 0.014). Overall, the FACT score was inversely correlated with the number of positive serotype-specific antibody levels [rho (ρ) = -0.38, p = 0.04]. The proportions of subjects with 12 or more positive serotype-specific antibodies among non-asthmatics and asthmatics below and above the median of the FACT scores were 86, 50 and 38%, respectively (p = 0.052).
Conclusions: The FACT score may help us identify a subset of asthmatics with immune incompetence. Study findings need to be replicated in a larger study.
Keywords: Asthma; FACT score; epidemiology; immunity; immunodeficiency; infection; pneumococcal.