Effects of COVID-19 pandemic-associated reduction in respiratory infections on infantile asthma development.

Background: It is speculated that the coronavirus disease 2019 (COVID-19) pandemic-associated reduction in the prevalence of respiratory tract infections has influenced the incidence of asthma in young children. Objectives: We investigated an association between the reduction in viral infections and the reduction in asthma in young children. Methods: The subjects were infants born in the early stages of the COVID-19 pandemic in Japan, which began in February 2020. A questionnaire survey related to asthma and allergy was conducted at 18 months and 3 years of age. These results were compared to those of age-matched infants during the nonpandemic period. Results: There were no epidemics of viral infectious diseases until the target child was 18 months old. At 18 months, the incidence of asthma/asthmatic bronchitis diagnosed by physicians in pandemic children was significantly lower than that in nonpandemic children. In 3-year-olds, no marked difference was observed between nonpandemic infants and pandemic children, except for an increase in respiratory syncytial virus infection in pandemic children. In a comparative study of the same children at ages 18 months and 3 years, an increased prevalence of asthma/asthmatic bronchitis was observed in pandemic children. Furthermore, the incidence of asthma after respiratory syncytial virus infection in pandemic infants was significantly lower than that in nonpandemic children. Conclusion: The COVID-19 pandemic-associated reduction in respiratory tract infections may have reduced the incidence of asthma in early childhood, and respiratory syncytial virus infection after 18 months of age had little effect on the onset of asthma. These results indicate the importance of preventing respiratory tract infections in early infancy.

Skull Base Fracture or Abuse Suspicion Based on Intraorbital Lymphangioma Secondary to Periorbital Hematoma.

Intraorbital lymphangiomas are among the orbital tumors that can cause sudden eye protrusion in children. In children with periorbital hematoma (panda eye sign), a skull fracture or abuse is likely first considered as the differential diagnosis. A 7-month-old boy presented to the ophthalmologist with complaints of swelling of the right upper eyelid, subconjunctival hemorrhage on the right ear side, and periorbital subcutaneous hemorrhage, which had appeared since the morning of the day before the visit. The eyeball did not protrude. Based on the interview and clinical findings, right eyeball contusion was suspected. The patient was then followed up for observation. Later, during the physical examination, the abovementioned symptoms were noted. Hence, the patient was admitted for a close examination based on the suspicion of skull base fracture and abuse. Contrast-enhanced magnetic resonance imaging (MRI) after admission revealed a multifocal cystic structure within the right intraorbital muscular cone. Thus, he was diagnosed with right intraorbital lymphangioma. Intraorbital lymphangioma may not show ocular protrusion, and this disease should be considered in cases where abuse is suspected, considering the periorbital subcutaneous hemorrhage.

Clinical application of a lung sound analysis in infants with respiratory syncytial virus acute bronchiolitis.

BACKGROUND: Objective investigation of the characteristics of acute bronchiolitis in infants is important for its diagnosis and treatment. METHODS: Lung sound data of 50 patients diagnosed with respiratory syncytial virus (RSV) acute bronchiolitis (m:f = 29:21, median of age 7 months), 20 patients with RSV acute respiratory tract infections without acute bronchiolitis (m:f = 10:10, 5 months) and 38 age-matched control infants (m:f = 23:15, 8 months) were analyzed using a conventional method and compared. Furthermore, the relationships between lung sound parameters and clinical symptoms (clinical score, length of hospital stay and SpO2 level) in the bronchiolitis and the non-bronchiolitis patients were examined. RESULTS: Results of lung sound analysis showed that the inspiratory sound power of patients with RSV respiratory tract infections was low and the expiratory sound power was high compared with those of the controls. When the patients with RSV respiratory tract infections were divided into the bronchiolitis and non-bronchiolitis groups, the expiratory/inspiratory ratio of the bronchiolitis patients was greater than that of the non-bronchiolitis patients. There was no difference in the clinical symptoms, clinical score and length of hospital stay between the bronchiolitis and non-bronchiolitis patients, except for the SpO2 level on admission. CONCLUSION: Lung sound analysis confirmed that patients with RSV acute bronchiolitis present with marked airway narrowing. Considering these results as a characteristic of acute bronchiolitis, it would be meaningful to reflect it in the improvement of diagnosis, treatment and subsequent management.

Effect of wheeze and lung function on lung sound parameters in children with asthma.

BACKGROUND: In children with asthma, there are many cases in which wheeze is confirmed by auscultation with a normal lung function, or in which the lung function is decreased without wheeze. Using an objective lung sound analysis, we examined the effect of wheeze and the lung function on lung sound parameters in children with asthma. METHODS: A total of 114 children with asthma (males to females = 80: 34, median age 10 years old) were analyzed for their lung sound parameters using conventional methods, and wheeze and the lung function were checked. The effects of wheeze and the lung function on lung sound parameters were examined. RESULTS: The patients with wheeze or decreased forced expiratory flow and volume in 1 s (FEV1) (% pred) showed a significantly higher sound power of respiration and expiration-to-inspiration sound power ratio (E/I) than those without wheeze and a normal FEV1 (% pred). There was no marked difference in the sound power of respiration or E/I between the patients without wheeze and a decreased FEV1 (% pred) and the patients with wheeze and a normal FEV1 (% pred). CONCLUSIONS: Our data suggest that bronchial constriction in the asthmatic children with wheeze similarly exists in the asthmatic children with a decreased lung function. A lung sound analysis is likely to enable an accurate understanding of airway conditions.

A Boy Presenting with a Fever and Pancytopenia Diagnosed with Systemic Lupus Erythematosus without a Positive Anti-ds-DNA Antibody Result or Hypocomplementemia: A Case Report.

BACKGROUND: Hematological involvement, including anemia, leukopenia, lymphopenia, and thrombocytopenia, is one of the most common manifestations of childhood-onset systemic lupus erythematosus (cSLE). Specifically, relatively severe forms of hematological involvement, such as macrophage activation syndrome (MAS) and thrombotic microangiopathy, occur in the course of the disease. Positivity for anti-double stranded-DNA (ds-DNA) antibody and hypocomplementemia are important as not only criteria of diagnosing cSLE but also in the determination of the disease activity. CASE REPORT: A 13-year-old boy without pre-existing disease was referred to our hospital chiefly complaining of a fever for > 7 days, long-lasting malaise, nausea, and non-malar face rash. His blood examination showed pancytopenia and hyperferritinemia, but positive results for anti-ds-DNA antibody and hypocomplementemia were not recognized. Bone marrow aspiration revealed no evidence of malignant diseases, hemophagocytic lymphohistiocytosis, or MAS. A renal biopsy for the differential diagnosis of proteinuria and hematuria revealed class IIIa +V lupus nephritis, leading to the diagnosis of cSLE. CONCLUSIONS: It is important for cSLE to be considered in patients with pancytopenia, even those without positive anti-ds-DNA antibody findings or hypocomplementemia, and for aggressive approaches to be adopted for the differential diagnosis, including a renal biopsy.

Allergic Sensitization Is Crucial for the Suppressive Role of Streptococcus pneumoniae in the Acute Exacerbation of Asthma.

INTRODUCTION: Allergic sensitization is an important factor in the development, severity, and exacerbation of asthma, which is attributed to type 2 (T2) inflammation. Evidence suggests that respiratory bacterial pathogens (e.g., Streptococcus pneumoniae) exert suppressive effects on airway T2 inflammation. To clarify the role of allergic inflammation in bacterial colonization in asthma based on allergic sensitization, we investigated pharyngeal bacterial colonization, biomarkers (e.g., serum eosinophil cationic protein (ECP) and cytokines/chemokines), and symptoms in the acute exacerbation of childhood asthma. METHODS: Pharyngeal samples were collected from 53 children (mean/median age 2.7/2.5 years). Serum levels of total and allergen-specific IgE against aeroallergens, ECP, and 17 cytokines/chemokines were measured. RESULTS: Allergic sensitization was recognized in 62.2% patients. S. pneumoniae, Moraxella catarrhalis, Haemophilus influenzae, and other bacteria were detected in 47.1%, 11.3%, 11.3%, and 30.1% of all patients, respectively. Patients with S. pneumoniae had a significantly shorter duration of wheezing than those without (4.7 ± 3.6 vs. 7.1 ± 3.5 days, p = 0.024). In patients with allergic sensitization, patients with S. pneumoniae had a significantly shorter duration of wheezing than those without (4.0 ± 3.6 vs. 7.7 ± 4.0 days, p = 0.003). Serum total IgE was significantly lower in patients with S. pneumoniae than in those without (81.9 [7.8-894] vs. 287 [4.4-1,840] IU/mL, p = 0.014). Serum ECP was significantly higher (33.1 [2-109] vs. 7.8 [3-35] ng/mL, p = 0.042), and IFN-γ was significantly lower (5.6 [4-10] vs. 16.4 [7-28] pg/mL, p = 0.032) in patients with allergic sensitization than those without. DISCUSSION/CONCLUSION: Our results suggested that the suppressive effects of S. pneumoniae colonization were observed only in patients with allergic sensitization, wherein serum total IgE, ECP, and IFN-γ may have an important role on acute exacerbation of asthma.

Effect of Post-nasal Drip on Overnight-cough Frequency and Cough Pattern in Children with Asthma.

OBJECTIVE: In children, post-nasal drip (PND)-induced cough is speculated. However, the relationship between PND and cough is still unclear. METHODS: During acute exacerbation of asthma, the number of overnight coughs and the cough pattern were compared in the children with atopic asthma with PND (n = 8) and the children with atopic asthma without PND (n = 27). All subjects had allergic rhinitis according to our original cough monitor. RESULTS: The total number of overnight coughs was significantly higher in the subjects with PND than in the subjects without PND (P < 0.05). In contrast, the overnight cough pattern of the subjects with PDN was found to be the same as in the subjects without PND, showing an increase in the number of coughs at the sleep onset and in the early morning. CONCLUSION: Our results suggest that PND may increase the number of nighttime coughs in children with atopic asthma and allergic rhinitis. In contrast, the overnight cough pattern was the same in the two groups, suggesting that this specific cough pattern is due to allergic inflammation of the upper and lower airways.

Breath sound analyses of infants with respiratory syncytial virus acute bronchiolitis.

INTRODUCTION: The reliability of a breath sound analysis using an objective method in infants has been reported. OBJECTIVE: Breath sounds of infants with respiratory syncytial virus (RSV) acute bronchiolitis were analyzed via a breath sound spectrogram to evaluate their characteristics and examine their relationship with the severity. SUBJECTS AND METHODS: We evaluated the inspiratory and expiratory breath sound parameters of 33 infants diagnosed with RSV acute bronchiolitis. The sound powers of inspiration and expiration were evaluated at the acute phase and recovery phase of infection. Furthermore, the relationship between the breath sound parameters and the clinical severity of acute bronchiolitis was examined. RESULTS: Analyses of the breath sound spectrogram showed that the power of expiration as well as the expiration-to-inspiration sound ratio in the mid-frequency (E/I MF) was increased in the acute phase and decreased during the recovery phase. The E/I MF was inversely correlated with the SpO2 and positively correlated with the severity score. CONCLUSION: In infants with RSV acute bronchiolitis, the sound power of respiration was large at the acute phase, significantly decreasing in the recovery phase. In 61% of participants, nonuniform, granular bands were shown in the low-pitched region of the expiratory spectrogram.

Anti-cyclic Citrullinated Peptide Antibody-positive Girl with Chronic Polyarthritis Later Diagnosed with Juvenile Systemic Lupus Erythematosus: A Case Report.

BACKGROUND: Arthritis is one of the earliest symptoms of juvenile systemic lupus erythematosus (SLE) but is unusual in cases presenting with chronic arthritis or deforming/erosive arthritis. Overlap of juvenile idiopathic arthritis (JIA) and juvenile SLE is a rare clinical condition known as "rhupus" syndrome. The clinical and serological characteristics of rhupus syndrome in children remain to be established. In addition, no studies regarding anti-cyclic citrullinated peptide (CCP) antibody in juvenile SLE or juvenile rhupus syndrome have been reported. CASE REPORT: A 12-year-old girl suffered from polyarthralgia lasting for one week. She was tentatively diagnosed with polyarticular JIA because of her symptom of chronic arthritis and a positive result for anti-CCP antibody. After six months of follow-up for JIA, she presented with a fever, malar rash, and worsening of arthralgia. Laboratory examinations revealed hypocomplementemia and a positive result for anti-double-stranded DNA antibody. She was diagnosed with juvenile SLE. CONCLUSIONS: It is important to note that patients with chronic arthritis, as well as those with anti-CCP antibody-positive polyarthritis, should be carefully followed for their clinical and serological condition, considering the possibility of them developing juvenile SLE.

A new method for objectively evaluating nocturnal cough in adults.

BACKGROUND: For the management of cough diseases in adults, an objective method of evaluating nocturnal cough is required. METHODS: In Study 1, a cough monitoring system was evaluated using 25 adult volunteers. In Study 2, the cough monitoring system was validated using 20 samples from 10 adult patients with cough diseases obtained overnight. In hospitalized patients, our original cough monitoring system with a microphone and accelerometer was used. At the same time, coughs were recorded using a video camera with digital sound recording. The number of coughs in each 8-h video-audio recording was counted manually by three trained observers. All cough data were printed out, and the basal number of cough events, using both the printed-out data and video-audio recordings, were then calculated by three observers. RESULTS: In Study 1, the cough monitoring system demonstrated good agreement with the number of coughs counted by examiners (sensitivity 99.2%, specificity 98.9%). In Study 2, there was significant agreement in the counts of natural coughs between our system and the video-audio method (p < 0.0001) and between our system and the basal cough events (p < 0.0001). CONCLUSIONS: Our method demonstrated excellent agreement with the video-audio recording method in adults and is considered extremely useful for the objective monitoring of overnight cough in adult patients with cough diseases.

Antibiotic Treatments Prolong the Wheezing Period in Acute Exacerbation of Childhood Bronchial Asthma.

INTRODUCTION: Although current guidelines recommend against routine antibiotic prescription for acute exacerbation of bronchial asthma, children with acute exacerbation of asthma receive antibiotic treatment more frequently. In addition, those antibiotics are often prescribed only for exacerbation of asthma without concurrent bacterial infection. OBJECTIVE: To clarify the association between antibiotic treatment and bacterial colonization in acute exacerbation of asthma, we investigated whether or not antibiotics affect the clinical condition, laboratory findings, and pharyngeal bacterial colonization in those patients. METHODS: Potential bacterial pathogens were investigated in pharyngeal samples of 111 children with acute exacerbation of asthma (mean/median age: 2.8/2.6 years old, respectively). We collected clinical data, such as the duration of wheezing and antibiotic use, and measured the peripheral white blood cell counts, C-reactive protein, and serum levels of total and allergen-specific IgE. RESULTS: Antibiotics were used in 50.5% patients with acute asthma exacerbation and included cephalosporin, penicillin, macrolide, and others. Episodes of wheezing were significantly longer in patients with antibiotic treatment than in those without it (6.7 ± 3.6 days vs. 6.0 ± 3.1, p = 0.044). Similarly, episodes of wheezing were significantly longer in moderate exacerbation patients with antibiotics than in those without them. Furthermore, in patients with Streptococcus pneumoniae, antibiotic treatment was associated with an extended duration of wheezing in cases of acute moderate exacerbation (7.0 ± 2.4 days vs. 4.8 ± 4.1, p = 0.043). CONCLUSIONS: These results suggest that antibiotic treatment in acute exacerbation of asthma might lead to longer asthmatic symptoms, specifically in patients with pharyngeal S. pneumoniae colonization.

Antitussive Effect of a Chest Band in Patients with Interstitial Lung Disease: The Preliminary Results from a Pre-post Intervention Study.

Objective Evidence supporting the efficiency of clinically administered therapies against interstitial lung disease (ILD)-related cough is limited. Thus, we conducted a study to evaluate the efficacy of short-term use of chest bands on cough in patients with ILD. Methods This pre-post intervention study was performed at two university hospitals between April 2017 and August 2020. Scores of the visual analog scale (VAS) for cough severity (in terms of frequency and intensity), Leicester Cough Questionnaire (LCQ)-acute, and frequency scale for symptoms of gastroesophageal reflux disease (FSSG) were assessed before and after the use of the chest band (24/48 hours). Patients The study included patients with idiopathic interstitial pneumonias (IIPs) or connective tissue disease-associated interstitial lung disease (CTD-ILD). Results Four patients with IIPs and seven with CTD-ILD were included in the analysis. The cough intensity and LCQ-acute total score improved significantly after the use of the chest band (p=0.007 and p=0.005, respectively), although the cough frequency showed no significant reduction (p=0.074). Furthermore, the FSSG total and acid-reflux symptom scores improved (p=0.018 and p=0.027, respectively), and a negative correlation between the change in LCQ-acute total score and that in FSSG score for acid-reflux symptoms was observed (Spearman rho =-0.841, p=0.001). Conclusion The results of the current study suggest that chest bands might be useful for treating chronic refractory cough in patients with ILD and gastroesophageal reflux disease. However, these results should be interpreted with caution due to methodological limitations associated with this study.

A Family Case of COVID-19 Pneumonia with Different Chest CT Features and Duration of SARS-CoV-2 Shedding: a Case Report from Japan.

Coronavirus disease 2019 (COVID-19) pneumonia in children characteristically has a milder clinical presentation, with milder inflammatory biomarkers and radiological findings. Accumulating evidence indicates a difference in chest computed tomography (CT) features and the duration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shedding between children and adults. Here, we report a family case of COVID-19 pneumonia in which 2 brothers (aged 14 years and 2 years) had different findings. On admission, the 2-year-old brother had few symptoms with no signs of pneumonia, whereas the older brother had presented with pneumonia on admission. Both were positive for SARS-CoV-2 infection on polymerase chain reaction and showed obvious characteristic signs of COVID-19 pneumonia on chest CT. However, CT findings in the younger brother were nonspecific and similar to those of other pneumonias. The older brother required longer treatment because of the longer shedding period of SARS-CoV-2 detected in nasopharyngeal samples. Both boys were discharged without complications. This family case suggests that the clinical features of COVID-19 pneumonia might differ between younger and older children.

Differences in Virus Detection and Cytokine Profiles between First Wheeze and Childhood Asthma.

OBJECTIVE: To distinguish between first wheeze and asthma in early childhood, we investigated respiratory viruses and cytokine/chemokine profiles among patients with first wheeze and established asthma. METHODS: We enrolled children with acute exacerbations of wheezing (17 first wheeze and 32 asthma) and 11 controls (no wheezing) aged between 10 months and 6 years. Nasal aspirates were obtained, and virus detection was performed with antigenic assay kits and/or RT-PCR. Serum 27 cytokines/chemokines were assayed by a multi-cytokine detection system. RESULTS: Rhinovirus and respiratory syncytial (RS) virus were dominant in acute exacerbations of asthma. However, many types of viruses were isolated in first wheeze. Serum IL-8 and IL-12 values were significantly higher in first wheeze than in acute asthma or the controls. IL-5 and IP-10 levels in acute asthma and first wheeze cases were higher than in the controls. Both of them were significantly higher in cases of acute asthma than in convalescence stage of asthma cases. Only IP-10 was significantly higher in first wheeze than in convalescence stage of first wheeze cases. CONCLUSIONS: Different profiles in virus detection and production of IL-8 and IL-12 might distinguish between first wheeze and childhood asthma.

The Suppressive Role of Streptococcus pneumoniae Colonization in Acute Exacerbations of Childhood Bronchial Asthma.

INTRODUCTION: Little is known about the association between bacterial infections and exacerbations of bronchial asthma. OBJECTIVE: To elucidate the effect of bacterial infections on bronchial asthma, we examined pharyngeal bacterial colonization, duration of wheezing, and serum levels of cytokines and chemokines during acute exacerbations of asthma in children. METHODS: Potential bacterial pathogens were investigated in pharyngeal samples and viruses obtained from nasal secretions of 111 children who were outpatients and/or in patients with acute exacerbations of asthma (mean/median age: 2.8/2.6, respectively). We also measured serum levels of 27 different cytokines/chemokines. RESULTS: Pharyngeal bacterial cultures were positive in 110 of 111 children. The 3 major bacterial pathogens were Streptococcus pneumoniae (29.7%), Moraxella catarrhalis (11.7%), and Haemophilus influenzae (10.8%). M. catarrhalis was detected more frequently in patients with pneumonia. Furthermore, patients with S. pneumoniae colonization had significantly shorter wheezing episodes than those without it. In contrast, the duration of wheezing did not differ significantly among cases with other bacteria such as M. catarrhalis and H. influenzae. Furthermore, the length of wheezing episode in patients with S. pneumoniae colonization showed significant inverse correlation with peripheral white blood cell count, neutrophil count, and C-reactive protein, while there was no significant correlation between duration of wheezing and these 3 parameters among patients with M. catarrhalis or H. influenza. Among the 27 cytokines/chemokines, only serum tumor necrosis factor (TNF)-α was significantly lower in patients with S. pneumoniae colonization than in those without it. CONCLUSIONS: These results suggested that pharyngeal S. pneumoniae colonization plays a suppressive role on the pathophysiology during acute exacerbations of asthma.

Objective measurement of nocturnal cough in infants with acute bronchiolitis.

OBJECTIVES: The objective measurement of the cough severity and the assessment of the pattern of nocturnal coughing could be useful in the treatment of respiratory diseases in children. STUDY DESIGN: In children with respiratory syncytial virus (RSV)-induced acute bronchiolitis, coughs were recorded using our original system with a microphone and accelerometer, and analyzed using our customized software program. The number of coughs in every 30-minute interval was measured in patients with acute bronchiolitis (n = 20), and their results were compared with those of infants with asthma exacerbation (n = 16). RESULTS: The cough count in children with acute bronchiolitis (median: 108.0/night) was almost as high as that in children with asthma exacerbation (median: 119/night). However, the time-dependent pattern of overnight cough was different in infants with acute bronchiolitis and those with asthma exacerbation. In the infants with asthma exacerbation, cough frequency significantly increased while falling asleep and waking up as compared to midnight (p < 0.001 and p < 0.001, respectively). However, these differences were not found in infants with acute bronchiolitis. CONCLUSIONS: Our data demonstrated that the number of coughing events due to acute bronchiolitis was similar to that of acute asthma exacerbation, although the acute bronchiolitis did not show a characteristic overnight cough pattern.

A breath sound analysis in children with cough variant asthma.

BACKGROUND: Cough variant asthma (CVA) is characterized by a chronic cough and bronchial hyperresponsiveness without confirmation of wheezing. Using a breath sound analyzer, we evaluate the characteristics of breath sound in children with CVA. METHODS: Nine children with CVA (median age, 7.0 years) participated. The existence of breath sounds was confirmed by sound spectrogram. Breath sound parameters, the frequency limiting 50% and 99% of the power spectrum (F50 and F99), the roll-off from 600 to 1200 Hz (Slope) and spectrum curve indices, the ratio of the third and fourth area to the total area of the power spectrum (P3/PT and P4/PT) and the ratio of power and frequency at 50% and 75% of the highest frequency of the power spectrum (RPF75 and RPF50) were calculated before and after ß2 agonist inhalation. A spirogram and/or forced oscillation technique were performed in all subjects. RESULTS: On a sound spectrogram, wheezing was confirmed in seven of nine patients. All wheezing on the image was polyphonic, and they almost disappeared after ß2 agonist inhalation. An analysis of the breath sound spectrum showed that PT, P3/PT, P4/PT, RPF50 and RPF75 were significantly increased after ß2 agonist inhalation. CONCLUSIONS: Children with CVA showed a high rate of inaudible wheezing that disappeared after ß2 agonist inhalation. Changes in the spectrum curve indices also indicated the bronchial reversibility. These results may suggest the characteristics of CVA in children.

Characteristics of breath sound in infants with risk factors for asthma development.

BACKGROUND: Breath sound parameters have been suggested as biomarkers of the airway narrowing in children. Using a commercially available breath sound analyzer, the characteristics of the airway condition were investigated in infants with the risk factors for asthma development. METHODS: A total of 443 infants (mean age, 9.9 months; range, 3-24 months) were included in the present study. The breath sound parameters of the frequency limiting 99% of the power spectrum (F99), the roll-off from 600 to 1200 Hz (Slope) and spectrum curve indices, the total area under the curve of the dBm data (A3/AT) and the ratio of power and frequency at 50% and 75% of the highest frequency of the power spectrum (RPF75 and RPF50), were evaluated. Using an ATS-DLD based original Japanese questionnaire, we examined the characteristics of airway condition of infants. RESULTS: Finally, 283 infants in good health were included in the present study. The RPF75, RPF50, Slope and F99 in infants with positive results of allergy and atopic dermatitis were significantly increased more than those in the infants with negative result. CONCLUSIONS: Our data highlight the characteristics of breath sounds in infants with risk factors for asthma. The breath sound analysis may be useful for assessing the airways of infants for asthma development.

Clinical Application of High-pitched Breath Sound in Children with Asthma.

OBJECTIVE: Breath sound parameters have been suggested to be a new biomarker of airway conditions in asthmatic patients. We investigated new breath sound parameters to determine their utility for evaluating asthmatic children. METHODS: Fifty-seven children (mean age, 9.0 years, 6-16 years) were included in the present study. The new breath sound parameters, the area under the curve (AUC)>1,000 Hz (A1000 [dBm·Hz]) and the ratio of the A1000 to the total AUC at 100 Hz to the highest frequency of the dBm power spectrum (AT) (A1000/AT [%]) were measured before and after ß2 agonist inhalation. Spirography and the forced oscillation technique were also used to evaluate all subjects. RESULTS: The value of A1000 was negatively correlated with the FEV1 (p=0.028). The increase in the ΔFEV1 was correlated with the decrease in the ΔA1000 (p=0.001) and the ΔA1000/AT (p=0.036). CONCLUSIONS: The A1000 indicates the airway condition, and the ΔA1000 and the ΔA1000/AT well describe the dilatation of the airways. These parameters are useful for the assessment of bronchial reversibility in asthmatic children.