Objective evaluation of wheezing in normal infants

• Published in: Pediatrics international 2019-10, Vol.61 (10), p.956-961
• Main Authors: Murayama, Yoshifumi, Shioya, Hiromi, Tadaki, Hiromi, Miyamoto, Manabu, Yoshihara, Shigemi, Tabata, Hideyuki, Furuya, Hiroyuki, Uchiyama, Atsushi, Mochizuki, Hiroyuki
• Format: Article
• Language: English
• Subjects: Asthma; Asthma - diagnosis; Asthma - epidemiology; Asthma - etiology; breath sound spectrogram; Case-Control Studies; Child, Preschool; Female; Humans; Infant; Infants; Japan - epidemiology; Male; Pediatrics; Respiratory Sounds - diagnosis; Respiratory Tract Infections - diagnosis; Respiratory Tract Infections - epidemiology; Respiratory Tract Infections - physiopathology; Risk Assessment; Sound; sound spectrum; Wheezing
• ISSN: 1328-8067; 1442-200X
• DOI: 10.1111/ped.13994

Background To evaluate the frequency of wheezing in infants, the presence of wheezing was examined in normal infants using a breath sound analyzer, Methods A total of 443 infants (age range, 3–24 months) were included in the present study. The existence of audible wheezing and faint wheezing/inaudible wheezing‐like noises (FW) was confirmed on chest auscultation and a sound spectrogram. The breath sound parameters of the sound spectrum, frequency limiting 99% of power spectrum (F99), roll‐off from 600 to 1,200 Hz (slope) and spectrum curve indices, total area under the curve of dB data (A3/AT and B4/AT), and ratio of power and frequency at 50% and 75% of the highest frequency of the power spectrum (RPF50 and RPF75) were calculated. Using an original Japanese questionnaire, we examined the characteristics of the airway condition of all infants. Results Finally, a total of 398 infants were analyzed in the present study, and 283 were in good health while 115 had acute respiratory infection (ARI) in the last 7 days. No infants had audible wheezing on auscultation. Three infants without ARI (1.1%) and 10 infants with ARI (8.7%) had FW. In the evaluation of breath sound parameters, there were no marked differences between the infants with and without FW. Conclusions Using a breath sound analyzer, wheezing and FW were recognized in only a few infants in good health. Infants recognized to have audible wheezing in daily practice may be at risk of developing recurrent wheezing/asthma.