This is an exploratory study designed to optimize, standardize, and validate novel breath biomarkers; there are no objective endpoints. The goal of this study is to generate pilot data to be used to generate hypothesis-driven studies.

Exhaled breath has three fractions - gaseous breath, volatile breath, and breath condensate. Biomarkers have been identified in each of these fractions and non-invasive collection methods have been developed. Exhaled breath can be safely and easily performed in all patient populations, including neonatal children and the elderly. We have shown that relative to normal controls, condensed exhalates obtained from asthmatic subjects reproducibly contain elevated concentrations of oxides of nitrogen and are more acidic (having hydrogen ion concentrations two to three log orders higher). We wish to extend these studies across all breath fractions and other lung diseases and respiratory processes including viral upper respiratory tract infections, cystic fibrosis, pneumonia, pulmonary hypertension, bronchiolitis obliterans, chronic obstructive pulmonary disease, tracheostomized patients and cigarette smokers. Through this study extension, we will obtain pilot data/preliminary information about the potential utility of this new technique to non-invasively evaluate disease status in various respiratory diseases. We also wish to obtain data regarding specificity by evaluating the exhaled breath obtained from patients with non-respiratory illnesses, such as, but not limited to diabetes, gastroenteritis, and various inflammatory disorders. We think it is likely that the exhaled biomarkers reflect underlying airway inflammation and infection.

Following informed consent, exhaled breath will be passively collected from subjects during quiet oral breathing through a simple mouthpiece or mask. Exhaled breath will be diverted into a collection device, which may include a bag, tube, or other device with minimal resistance. The collection process, including completing forms, will not exceed 30 minutes.

Subjects may be asked to provide several specimens during the course of their inpatient stay or clinic visit to obtain longitudinal data.

At no time will the patients be breathing anything other than ambient air with or without oxygen enrichment as clinically indicated. Inhaled air will not be manipulated.

Exhaled breath collection technique is completely comfortable, causing neither discomfort nor fatigue.

Inclusion Criteria:

• Study sample will consist of individuals aged 4-110 with a diagnosis of acute or chronic respiratory disorders, or metabolic or systemic conditions involving diffuse inflammation, or normal subjects with no pulmonary disease.

Exclusion Criteria:

• Subjects that are unable or unwilling to cooperate with specimen collection.