RECURRENT stone-formation is probably the most important problem in the after-care of patients who have undergone operations for renal and ureteric calculi. Surgical treatment usually provides immediate relief from symptoms and some improvement in kidney function, but it confers little permanent benefit unless steps can be taken to prevent the formation of other stones. The thoughtful stone patient is anxious to know the frequency of this complication, and asks advice about preventive measures. In spite of the considerable volume of research that has been carried out on these subjects in the last few decades it is still difficult to answer his first question accurately or his second adequately.An attempt is made in this paper to assess the incidence of recurrence in a series of patients who have undergone operative treatment for upper urinary tract stone. The practical application of this information to the prevention of recurrence is briefly discussed.Results of Other Investigations.-At the Annual Meeting of the British Association of Urological Surgeons in 1948, Professor John Hellstrom remarked that there had been surprisingly few investigations in recent years to determine the frequency of recurrence after operations for renal lithiasis. Table I indicates that the most modern studies of all aspects of recurrence were conducted by Twinem (1937), Oppenheimer (1937), and Spence and Baird (1939), who must have been given considerable food for thought by the fact that some fifteen to twenty years had elapsed since the well-known investigations of Cabot and Crabtree (191 5), Barney (1922 a), Braasch and Foulds (1923), and Brongersma ( 1 924), without any significant reduction in recurrence rate. Swift Joly (1929) considered that Brongersma's report to the International Society of Urology in 1924 was the most complete and convincing review of the late results of the various operations for renal stone, and in many respects this is still true. His figures are worth recalling. Following thirty-eight cases of pyelolithotomy, recurrence was present in 23.6 per cent., compared with 35.5 per cent. recurrence after sixty-two cases of nephrolithotomy : but perhaps the most significant feature was Brongersma's discovery that only 16.1 to 16.4 per cent. of sterile cases recurred, compared with 50 to 54-8 per cent. of those infected. Hunner (1928), an enthusiastic advocate of urostasis and ureteral stricture as causes of stone-formation, followed seventy-eight of 302 cases and found 9.5 per cent. recurrence after kidney operations. Higgins (1 936) reported that his recurrence rate had been reduced from 16.4 to 4.7 per cent. by a strict dietary and follow-up regime. In a recent Hunterian Lecture Hamilton Stewart (1952) described the progress of 101 partial nephrectomies performed in the thirteen years prior to the early part o f 1950 : he re-examined eighty-seven of these and found recurrent calculi in only six (6.8 per cent.).
Reasons for Wide Variations in Reported RecurrenceRates.-There are several possible explanations for t...
