Volatile fatty acids in the faeces of patients in 'germ-free' isolation.

Faecal volatile fatty acids represent the end products of the metabolism of the anaerobic flora of the large bowel. The excretion of these volatile acids has been investigated in five leukaemic patients maintained in plastic ;germ-free' isolators. Under ;isolator' conditions there is a pronounced fall in volatile fatty acid excretion. The possibility that the measurement of these acids may be used to monitor anaerobic overgrowth and recolonization in these patients is discussed.