An 8-year-old with FVC significantly below predicted value and no change after albuterol: which disorder?

• A. Asthma
• B. Bronchitis
• C. Cystic fibrosis
• D. Skeletal deformity

Answer: (D)

A markedly reduced FVC with no improvement after a bronchodilator points to a restrictive problem rather than obstructive airway disease. FVC is the total air forcefully exhaled after full inhalation, and in restriction the lungs or chest wall can’t expand fully, so the vital capacity falls. A bronchodilator like albuterol works by opening airways; this helps conditions with reversible airway obstruction (such as asthma) but does not fix a fixed, mechanical limitation of chest wall expansion. In an 8-year-old, skeletal deformities such as scoliosis or other chest wall abnormalities limit thoracic compliance and reduce lung volumes, producing a low FVC that does not respond to bronchodilators. The other conditions listed involve obstructive processes where some bronchodilator responsiveness would be expected, not a fixed reduction in lung volumes due to skeletal deformity.