GC–MS analysis of breath odor compounds in liver patients

Liver diseases can cause a sweet, musty aroma of the breath, called fetor hepaticus. Even in a stage of cirrhosis, the disease can be asymptomatic for many years. Breath analysis might be helpful to detect occult liver pathology. This study examined whether specific breath odor compounds can be found in liver patients, suffering from cirrhosis, which might be useful for diagnosis. Fifty-two liver patients and 50 healthy volunteers were enrolled. Alveolar air was analyzed by gas chromatography–mass spectrometry. Using discriminant analysis a model for liver disease was built. Dimethyl sulfide, acetone, 2-butanone and 2-pentanone were increased in breath of liver patients, while indole and dimethyl selenide were decreased. Sensitivity and specificity of the model were respectively 100% and 70%. Fetor hepaticus is caused by dimethyl sulfide and to a lower extent by ketones in alveolar air. Breath analysis by GC–MS makes it possible to discriminate patients with breath malodor related to hepatic pathologies.