Tophi in Relation to Arthritis
How elated we are, and rightly, when in an obscure form of arthritis we pounce on these objective criteria of gout, how apt to deem our diagnostic quest as ended, and with what fatal glibness the time-worn “gout” slips from our lips, sure, alas, of ready and almost complaisant acceptance. Fallacious inference, all too prevalent, that the presence of tophi stamps any concomitant arthritis as “gouty.”
True, tophi are pathognomonic of gout, but their existence does not confer on their host immunity from all other forms of arthritis. In view of the increasing light shed upon joint disorders, who can doubt that (and this not only for our forefathers) the tophus has too often proved a veritable snare, allaying all diagnostic doubts, lulling us into false security? For an individual may, for example, exhibit auricular tophi and be the victim also of an arthritis, but the latter is not inevitably “gouty.” All that can be assumed at sight is merely that the joint disorder, whatever its nature, has ensued in a subject of “gouty diathesis.”
For it may be of specific infective origin, gonococcal, syphilitic, pneumococcal, etc. Quâ a concomitant arthritis, then, the diagnostic significance of tophi, at any rate when of ab-articular site, must not be overrated. It is at once a beacon and a warning. In other words, the diagnosis of a co-existent arthritis as “gouty” should not be entertained pending the exclusion of all other forms of arthritis.
Conversely, in the absence of tophi, the diagnosis of an arthritis as “gouty” is not absolute, but presumptive.
For in the lack of these objective stigmata how can the authenticity of our diagnosis be established? Is it not when achieved a nosological rather than a diagnostic feat? Put otherwise, is not our diagnosis, especially in initial attacks, largely topographical? Not that we would for one moment decry the advantage of realising the predilection of certain organisms for this or that particular joint: of the gonococcus for the sterno-clavicular, of typhoid for the hip, post-scarlatinal rheumatism for the phalangeal joints, etc. But we would drive home the fact that our diagnosis in initial attacks of “gout” is very largely topographical. Let but inflammatory trouble ensue in the big toe, and forthwith we assume it gout, as if, forsooth, this particular joint were immune from all other forms of disease, this, too, while in the same breath we comment on its extreme liability to injury. So, indeed, we maintain, is the marked predilection of gout for the toe joint explained. Is not this a little crude? Does not the same circumstance increase its liability to infection and, we may add, not less important, its proneness to static deformities? But to this we shall recur when discussing differential diagnosis.
To return, how often, apart from the above pitfalls, is the diagnosis “gout” arrived at without any search for tophi wherewith to support the assumption. Our contention is that even in primary attacks of gout our search for tophi should be exhaustive. If undiscoverable, why not be honest with ourselves and recognise that our diagnosis is presumptive pending their development?
Sir William Roberts on this point observes: “As a rule, diagnosis of acute articular gout is easy, but exceptional cases of difficulty occur. The gouty character of the inflammation is affirmed by the discovery of uratic concretions in the rim of the ear or elsewhere.”
Again, Sir William Osier, discussing the diagnosis of acute gouty polyarthritis, remarks: “We have had of late years several cases admitted for the third or fourth time with involvement of three or four of the larger joints. The presence of tophi has settled the nature of a trouble which in previous attacks has been regarded as ‘rheumatic.’”
One may, we think, gather from these two statements the inference that both these distinguished authorities hold tophi to be the only infallible criterion upon which to base a diagnosis of gouty arthritis. In my own practice I must affirm that I never feel justified in christening any arthritis as gouty unless I have discovered tophi, and then only when to the best of my ability all other known causes of arthritis have been excluded.