Table 2.
Concentrations of biomarkers used in the detection of different diseases. NS, not stated; ppb, parts per billion; ppmv, parts per million by volume.
| Disease | Study | Biomarker | Concentration | References | |
|---|---|---|---|---|---|
| Asthma | Lärstad (2007) | Ethane | NS | [26] | |
| NO | 19 ± 2 ppb (healthy subject); 30 ± 6.1 ppb (asthma patient) | ||||
| Pentane | NS | ||||
| Isoprene | 113 ppb | ||||
| Olopade (1997) | Pentane | Acute asthma: 8.4 ± 2.9 nmol/L | [33] | ||
| Pentane | Stable asthma: 3.6 ± 0.4 nmol/L | ||||
| Paredi (2000) | Ethane | Ethane: asthma not treated with steroids: 2.06 ± 0.30 ppb; asthma treated with steroids: 0.79 ± 0.1 ppb); healthy volunteers: 0.88 ± 0.09 ppb | [27] | ||
| NO: asthma not treated with steroids: 14.7 ± 1.7 ppb; asthma treated with steroids: 8.6 ± 0.5 ppb | |||||
| Dweik (2011) | NO | Low asthma patients: <25 ppb in adults; >20 ppb in children Intermediate asthma patients: 25–50 ppb in adults; 20–35 ppb in children High asthma patients: >50 ppb in adults; >35 ppb in children Persistently high asthma patients: >50 ppb in adults; 35 ppb in children |
[34] | ||
| COPD | Paredi (2000) | Ethane | 2.77 ± 0.25 | [35] | |
| Cystic fibrosis | Barker (2006) |
Pentane | 0.36 (0.24–0.48) ppb | [36] | |
| Dimethyl Sulfide | 3.89 (2.24–5.54) ppb | ||||
| Antuni (2000) | NO | Healthy volunteers: 7.3 (0.24) ppb; stable cystic fibrosis patients: 5.7 (00.29) ppb; unstable cystic fibrosis patients: 6.1 (0.72) ppb | [30] | ||
| CO | Healthy volunteers: 2.0 (0.1) ppm; stable cystic fibrosis patients: 2.7 (0.22) ppm; unstable cystic fibrosis patients: 4.8 (0.3) ppb | ||||
| Lung cancer | Bajtarevic (2009) | Isoprene | Median concentration: healthy volunteers: 105.2 ppb; cancer patients: 81.5 ppb | [32] | |
| Acetone | Median concentration: healthy volunteers: 627.5 ppb; cancer patients: 458.7 ppb | ||||
| Methanol | Median concentration: healthy volunteers: 142.0 ppb; cancer patients: 118.5 ppb | ||||
| Benzene | Median concentration: healthy volunteers: 627.5 ppb; cancer patients: 458.7 ppb | ||||
| Diabetes mellitus | Das (2016) | Acetone | Type 1 | 0.044–2.744 ppm (healthy volunteers); 2.2–21 ppm (diabetes patients) | [37] |
| Type 2 | 0.044–2.744 ppm (healthy volunteers); 1.76–9.4 ppm (diabetes patients) | ||||
| Spanel (2011) | Acetone | Type 2 | <800 ppb (healthy volunteers); >1760 ppb (diabetes patients) | [38] | |
| Helicobacter pylori | Kearney (2002) | Dioxide carbon and ammonia. | NS | [39] | |
| Hypolactasia | Metz (1975) | Hydrogen | Control: 0–3 ppmv; patients: 48–168 ppmv | [40] | |
| Liver fibrosis | Alkhouri (2015) | Acetone | Lower fibrosis group: 117.8 ppb; advanced fibrosis group: 224.2 ppb | [41] | |
| Benzene | Lower fibrosis group: 1.9 ppb; advanced fibrosis group: 8 ppb | ||||
| Carbon Disulfide | Lower fibrosis group: 1.6 ppb; advanced fibrosis group: 3.2 ppb | ||||
| Isoprene | Lower fibrosis group: 13.5 ppb; advanced fibrosis group: 40.4 ppb | ||||
| Pentane | Lower fibrosis group: 12.3 ppb; advanced fibrosis group: 19.5 ppb | ||||
| Ethane | Lower fibrosis group: 63.0 ppb; advanced fibrosis group: 75.6 ppb | ||||