Fractional Exhaled Nitric Oxide for Identification of Uncontrolled Asthma in Children.

Objectives: To determine the utility of Fractional Exhaled Nitric Oxide (FENO) in the identification of uncontrolled asthma in children on therapy, and to identify its cut-off value for determining asthma control. Methods: 207 children (age 5-15 y) with physician-diagnosed asthma on therapy with at least 12 months follow up were enrolled. Spirometry and FENO measurements were performed. Asthma control was assessed as per GINA guidelines. Sensitivity and specificity of various cut-off values of FENO (15 ppb, 20 ppb, 25 ppb, 30 ppb) for identification of status of control of asthma were calculated. Results: 156 (75%) children had uncontrolled or partly controlled asthma and 51 children were assessed to have controlled asthma. Median (IQR) FENO in children with controlled and uncontrolled asthma was 16 (11-23) ppb and 13 (11-25) ppb, respectively (P=0.26). No FENO cut-off had a reasonable combination of sensitivity and specificity to discriminate between controlled and uncontrolled asthma. Conclusion: FENO, in itself, does not have good discriminatory value in assessment of controlled and uncontrolled asthma in children on asthma therapy.

Fractional Exhaled Nitric Oxide in Children with Acute Exacerbation of Asthma.

Objective: To determine whether fractional exhaled nitric oxide (FENO) has a utility as a diagnostic or predictive maker in acute exacerbations of asthma in children. Design: Analysis of data collected in a pediatric asthma cohort. Setting: Pediatric Chest Clinic of a tertiary care hospital Methods: A cohort of children with asthma was followed up every 3 months in addition to any acute exacerbation visits. Pulmonary function tests (PFT) and FENO were obtained at all visits. We compared the FENO values during acute exacerbations with those at baseline and those during the follow up. Results: 243 asthmatic children were enrolled from August 2009 to December 2011 [mean (SD) follow up - 434 (227) days]. FENO during acute exacerbations was not different from FENO during follow up; however, FENO was significantly higher than personal best FENO during follow up (P < 0.0001). FENO during acute exacerbation did not correlate with the severity of acute exacerbation (P=0.29). The receiver operating characteristics curve for FENO as a marker for acute exacerbation had an area under the curve of 0.59. Cut-off of 20 ppb had a poor sensitivity (44%) and specificity (68.7%) for acute exacerbation. Conclusions: FENO levels during acute exacerbation increase from their personal best levels. However, no particular cut off could be identified that could help in either diagnosing acute exacerbation or predicting its severity.

Aeroallergen Sensitization in Childhood Asthmatics in Northern India.

Objective: To determine the prevalence of sensitization to common aeroallergens in asthmatic children and study the differences in characteristics of atopics and non atopics. Design: Analysis of data from a prospective cohort study. Setting: Pediatric Chest Clinic of tertiary care center in Northern India Patients: Asthmatic children from 5-18 year of age. Main outcome measures: Prevalence of sensitization to common aeroallergens. Results: Skin prick testing (SPT) was performed on 180 children above 5 years of age, with a mean (SD) age of 111.4 (34.2) months. 100 children (55.6%) were sensitized to at least one aeroallergen, suggesting atopy; 68 (37.8%) were sensitized to more than one allergen. 36.7% children were sensitized to housefly antigen; 31.1% to rice grain dust, 18.3% to cockroach, and 7.8% to house dust mite antigens. Atopic children had significantly higher median FENO during follow up than nonatopic children (17.5 ppb vs 13 ppb, P=0.002). There was a positive correlation between age and the number of allergens that an individual was sensitized to (r= 0.21; P=0.0049). Conclusions: More than half of asthmatic children in our cohort had sensitization to one or more aeroallergens suggesting atopy; sensitization was most commonly seen to housefly antigen and rice grain dust. Atopic children had significantly higher FENO measurements during follow up as compared to non-atopic children.

Assessment of Bronchodilator Response in Preschool Children by Pulmonary Function Tests.

We performed pulmonary function test to document bronchodilator response by using tidal breathing flow volume loop (TBFVL), rapid thoracic compression (RTC), and raised volume rapid thoracic compression (RVRTC) techniques. Thirty-nine children (mean age 45.2 months) were evaluated. The parameters that showed significant improvement after bronchodilator administration included TEF10/ PTEF ratio in TBFVL, and FEF25-75%, FEV1and PEF in RVRTC. None of the parameters measured in RTC showed significant improvement. We conclude FEV1, PEF and FEF25-75% in RVRTC have greater sensitivity for detection of airways changes.

HIV infection mimicking autoimmune disorder.

A 13-yr-old girl born to healthy parents presented with cough, fever, easy fatiguability, photosensitivity and alopecia. She had clubbing and diffuse crackles in the chest on examination. Her CT scan of the chest showed evidence of bronchiectasis with consolidation. Investigations for tuberculosis and collagen vascular disease were negative. In due course she developed features of raised intracranial tension. Her blood for HIV ELISA was positive with CD4 counts of 17/ microL. Her CSF, sputum, blood and urine specimen were all positive for Cryptococcus neoformans on culture. HIV was not considered initially because of her atypical presentation. There was no history of sexual abuse, her parents were healthy and she did not receive any blood transfusion in the past.