As a comorbid condition of sickle cell disease (SCD), asthma leads to increased complications and mortality. However, poor understanding of asthma phenotypes in SCD and the complex interaction with SCD-related airway inflammation, manifested by bronchial hyperresponsiveness or obstructive airway, pose a unique clinical challenge. The objective of this chapter is to provide a comprehensive review and discussion of epidemiology, pathophysiology, interactions, and clinical implications of airway hyperresponsiveness (AHR), obstructive airway, and asthma in SCD. Discussion will cover new understanding and limitations of asthma diagnosis and management in SCD. AHR, lower obstructive airway, and asthma are highly prevalent in SCD. Despite overlapping features, these entities are nonetheless distinct as demonstrated by basic science and clinical data. Diagnosis of asthma should be based on a physician assessment. We provide new unpublished data of a prospective study on diagnosing asthma in a small preschool population. Administered validated asthma-screening questionnaire to SCD children reveals good sensitivity and specificity as an asthma detection tool. It is unclear at this time if detection of bronchial lability or asthma early in life would result in better outcome of patients, or if improved control of SCD attenuates lower airway pathology. Being able to distinguish asthma from bronchial lability in the preschool age children would allow for appropriate intervention early in life.
Part of the book: Sickle Cell Disease