Diagnosis and Assessment
ÎÎThe intensity of the exercise challenge for the elite athlete should be 95%
or greater than actual or estimated HRmax, and dry medical-grade air
should be used in performing the challenge. (D)
ÎÎHyperosmolar aerosols may also be used as surrogates to exercise. (C)
Differential Diagnosis
ÎÎExercise-induced laryngeal dysfunction (EILD), primarily vocal cord
dysfunction (VCD) and other glottic abnormalities, may be elicited by
exercise and mimic EIB. Inspiratory stridor is a differentiating hallmark
sign with exercise-induced laryngeal dysfunction and not with EIB alone.
Flattening of the inspiratory curve on spirometric maneuver may be seen
concomitant with symptoms. Exercise-induced laryngeal dysfunction may
occur alone or with EIB. Failure to respond to asthma management is a key
historical feature suggesting EILD. (C)
ÎÎExercise-induced dyspnea and hyperventilation can masquerade as
asthma, especially in children and adolescents. (C)
ÎÎShortness of breath with exercise may be associated with underlying
conditions due to obstructive lung disease, such as chronic obstructive
pulmonary disease (COPD), or restrictive lung physiology, such as obesity,
skeletal defects (eg, pectus excavatum), diaphragmatic paralysis, and
interstitial fibrosis. (B)
ÎÎShortness of breath accompanied by pruritus and urticaria, with varying
other systemic symptoms, suggests exercise-induced anaphylaxis (EIAna)
rather than EIB. (C)
ÎÎIn the absence of objective evidence of EIB, breathlessness with exercise,
with or without chest pain, may be caused by cardiovascular, pulmonary,
or gastroenterologic mechanisms other than asthma. Appropriate
cardiopulmonary testing and/or referral to a cardiologist, pulmonologist,
or gastroenterologist may be necessary. (B)
ÎÎExercise-induced dyspnea is seen as a physiologic limitation in otherwise
healthy active individuals without bronchospasm. (C)
ÎÎThe association between EIB and gastroesophageal reflux disease (GERD)
is controversial, and probably there is no relationship. (A)
ÎÎ Psychological factors need to be considered in the differential diagnosis
of EIB. (D)
ÎÎDyspnea on exertion, which is prevalent in otherwise healthy, obese
individuals, is not associated with EIB. (C)
ÎÎMitochondrial enzyme deficiency with myopathy is a rare cause of exercise
limitation. (D)
