AN INCREASING NUMBER OF CALCIUM-OXALATE STONE EVENTS WORSENS TREATMENT OUTCOME

Current practice recommends metabolic evaluation of patients who have formed multiple renal stones, but not those with one stone or temporal ly remote stones. This presumes that recentness and recurrence imply g reater risk of new future stones. We hypothesize that number of stones reflects how long patients are permitted to form stones untreated, an d that forming more stones, itself, raises risk of future stones despi te treatment. Our report is a retrospective analysis of 371 male patie nts selected from a comprehensive clinical and laboratory data base co ntaining 2,527 patients with nephrolithiasis. Before treatment, number of stone events rises with time of observation, and rate of stone eve nt occurrence is constant or falls. During treatment, relapse is corre lated with number of pretreatment stones. Life table analysis showed i ncreasing relapse for patients grouped into those with one, two, and t hree or more stones. Even though number of stones seems controlled by the interval of observation before treatment, more stones predict high er relapse during treatment. Perhaps by leaving nuclei of crystals as residues, stones appear to promote new stones, and the practice of wai ting while patients declare themselves multiple stone formers may not always be the best.