Anomalous Sites for Initial Outbreaks
While primary attacks are in the vast majority of instances localised to the foot, if not actually to the toe, it is well to recollect that very rarely the knee, the wrist, elbow, or ankle may be the chosen spot. In such cases there is need for exceptional caution before committing oneself to a diagnosis of gout. Certainly not until all other known causes of acute arthritis of monarticular type have been excluded.
If in the knee or wrist, any possibility of injury or strain should be thoroughly canvassed. To make assurance doubly sure, a radiograph should always be taken. Specific infective forms of arthritis then call for careful elimination—i.e., gonococcal, etc. If there be no history of such, a painstaking search should be made for any local foci of infection, e.g., mouth and accessory cavities. If any be found, they should be radically treated, as it is much more likely that the arthritis is due thereto than to gout.
If, notwithstanding a meticulously careful investigation, no cause can be assigned, we may entertain the possibility of its being gout, the more legitimately if the subject be a middle-aged man coming of gouty ancestry and exhibiting himself tokens of this diathesis, i.e., tophi. It would be confirmatory, too, if, apart from its exceptional localisation, the joint disorder in its course conformed to that typical of gout in the toe, in other words if it was of sudden nocturnal onset, showed marked daily remissions in temperature and pain, responded swiftly to the action of colchicum, and was not protracted beyond the usual week or ten days.
Sir Hale White, discussing the diagnosis of acute gout of unusual localisation, remarks: “The real difficulty in acute cases comes when it is suggested that an acute arthritis with pyrexia and swelling and redness of a joint other than that of the great toe is caused by gout. I have recently seen the difficulty in one patient in the wrist, in another in the knee. Such cases, if they are not gout, are some bacterial arthritis.”