FLUTD is one of the intractable diseases encountered in feline practice. The July, 1993 edition of the JSAP carried an article by Sydney University, Associate Professor ADJ Watson in which he reviewed the work of Markwell (JSAP 34 pp157-162) and commented on the work of Osborne et al.

A significant point was that struvite crystalluria is a common finding in normal cats. He comments that:

‘Osborne and others (1992) hypothesize that matrix – crystalline plugs obstructing the urethra are formed because of the coincidence of urinary tract inflammation and crystalluria. As the causes of inflammation in these patients are unknown, 76.2% of cases of FLUTD in the series of Osborne and others (1989) can be said to have had unknown etiology’ .

In the limited number of cases biopsied by us the cellular infiltrates in bladder and urethra have been similar to our random foot pad samples. It would seem that cats with diet-induced periodontal disease are prone to the deposition of inflammatory cells in numerous tissues including the bladder and urethra. If this proves to be the case then 76.2% of cases in the Osborne et al series (1989) could possibly be attributed to this source.

In the other 23.8% of cases the inflammation has been attributed to a range of causes. Our belief is that in these cases periodontal disease-induced inflammation may well have played a principle role in the aetiopathogenesis . The concomitant belief being that the viruses and bacteria previously implicated as sole causative agents may now be seen either as incidental findings or another means by which the urinary tract inflammation is exacerbated.

It is acknowledged that our evidence is scanty in this area since we need to keep our clinical cases alive. One case monitored by ourselves continues with a high level of crystalluria. This caused us consternation at first but now could perhaps be seen as an aspect of the normal. At the time of first presentation with blockage this cat had its periodontal disease treated by radical dentistry. The cat is now maintained on a diet of raw chicken wings and raw rabbit legs without recurrence of periodontal disease or blockage of the urethra. Of course, we are not at liberty to biopsy the bladder and urethra in order to ascertain the presence or absence of inflammatory infiltrates. (The Cybernetic Hypothesis of Periodontal Disease in Mammalian Carnivores predicts a cascade of pathological consequences for periodontal disease-affected animals. See page 23)


Historically the function of medicine has been to diagnose extant clinical conditions. Clinicians experience enough difficulty making diagnoses and recommending treatment once pathology is in place. That the activity is retrospective has not hitherto caused much concern. (People pay doctors for disease treatment not health maintenance)

Often times in human medicine the patient can advise the clinician of symptoms. The very opposite is the case with animals both wild and domestic for they actively seek to disguise signs of chronic ill health. When one considers that the body is extremely adept at compensating whether it be for liver, kidney, bone marrow or similar failure then making a diagnosis prior to the end-stage collapse of the compensatory mechanism can be a difficult task.

That is, if one restricts oneself to the orthodox use of the clinical diagnostic pathway. If, however, one takes the view that all animals should be on a more nearly natural diet and free from periodontal disease then creation of health very often precedes identification of disease. This occurs because the basic assumption is made that diet and periodontal disease have a major impact on the wellbeing of the patient. Alteration of these two factors either solves the presenting problem or makes for a sound basis upon which to pursue further diagnosis and treatment. When presenting their animals for vaccination owners frequently believe them to be well. Change of diet at this time is frequently attended by an improvement in vitality. Owners are indignant and surprised as to how unwell their pets have been.

The following sets out in simplified fashion how the veterinarian possessing a high index of suspicion regarding the diet/periodontal disease/general health nexus takes cumulative decisions differing from his orthodox counterpart when working through the clinical diagnostic pathway.

One piece of information abstracted from the orthodox school of thought does in fact offer insight.

‘Subjective assessment can be just as important and by its nature is accepted with less stigma and finality, than is a hard figure, which is often given more authenticity and authority than is deserved’.

(Atwell R, 1992)