title: Radiographic and laboratory data ("the Megaprofile") can accurately guide medical management in the absence of stone analysis.
abstract: BACKGROUND
  Stone analysis is not always available, and recent studies reveal interlaboratory reporting differences, suggesting inaccurate reports. We sought to determine whether appropriate medical therapy could be made without stone analysis when imaging, history, and laboratory data were available.
  
  
  METHODS
  One hundred stone formers (SFs) were categorized as calcium oxalate, calcium phosphate, uric acid, or struvite based on a single analysis. Age, gender, body mass index, comorbidities, serum chemistries, 24-hour urine, and imaging information were incorporated into a "Megaprofile." Radiographic details about patients' stones were recorded. Attenuation: Size ratios were calculated to predict stone composition. Stone composition data were then withheld and three urologists (S.L.B., S.S., and S.Y.N.) evaluated each Megaprofile, making nutritional and pharmacologic recommendations. Next, a repeat evaluation ensued with stone analyses. Recommendations were compared with the gold standard being those made using stone composition data.
  
  
  RESULTS
  Without stone analysis, the panel recommended targeted nutrition therapy in 91% of cases, which remained unchanged once composition was revealed. Medication was prescribed in 68% of cases. Overall, therapy based on the Megaprofile without stone composition data was appropriate 93% of the time. In 7% of cases, therapy was changed after stone composition was revealed. In 21% of patients with recurrent urinary tract infections (UTIs), knowledge of stone composition altered therapy.
  
  
  CONCLUSIONS
  Medical, laboratory, and radiographic data provide sufficient information to direct both nutritional and pharmacologic therapy in most SFs (93%), but those with recurrent UTIs may derive more benefit from stone analysis prior to directed medical therapy.
authors.affiliation: Department of Urology, University of Wisconsin School of Medicine and Public Health , Madison, Wisconsin.
authors.forename: Sara L
authors.initials: SL
authors.lastname: Best
authors.forename: Sri
authors.initials: S
authors.lastname: Sivalingam
authors.forename: Kristina L
authors.initials: KL
authors.lastname: Penniston
authors.forename: Stephen Y
authors.initials: SY
authors.lastname: Nakada
mesh_terms: D000328:Adult; D000368:Aged; D000493:Allopurinol / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D015992:Body Mass Index; D002129:Calcium Oxalate / Q000032:analysis; D002130:Calcium Phosphates / Q000032:analysis; D015331:Cohort Studies; D004035:Diet Therapy; D004232:Diuretics / Q000627:therapeutic use*; D004791:Enzyme Inhibitors / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D017616:Magnesium Compounds / Q000032:analysis; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000032:analysis; D019357:Potassium Citrate / Q000627:therapeutic use; D000069877:Struvite; D049971:Thiazides / Q000627:therapeutic use; D013997:Time Factors; D014527:Uric Acid / Q000032:analysis; D014545:Urinary Calculi / Q000737:chemistry / Q000175:diagnosis* / Q000628:therapy; D014572:Urology
chemical_list: D000900:Anti-Bacterial Agents; D002130:Calcium Phosphates; D004232:Diuretics; D004791:Enzyme Inhibitors; D017616:Magnesium Compounds; D010710:Phosphates; D049971:Thiazides; D002129:Calcium Oxalate; D014527:Uric Acid; D000493:Allopurinol; C020243:calcium phosphate; D000069877:Struvite; D019357:Potassium Citrate