A suspicion of PCD can be made at examination, and confirmed by a laboratory test. Several blood quills will need to be removed, and a blood sample taken. Naive birds are susceptible to infection. The yeasts are also commonly found on fruit and in contaminated water. The infection often invades the oesophagus, crop, stomach and intestines.
Infections can be acute or chronic.
Acute infections show no real signs other than perhaps a little mucous. Chronic infections in the mouth look like white firm fluff which adheres to the lining of the mouth, and will often bleed if disturbed. It is also very painful for the bird and the bird will look fluffed and depressed. Bacterial and other fungal infections can look visually similar to Candida infections. The only definite way to diagnose this condition is to take a swab of the affected area and examine it under a microscope for the evidence of yeast organisms.