Improvements in the routine investigation of urinary calculi.
Results from an external quality assessment program of urinary calculi analysis are shown. Some analytical improvements have been observed since a similar investigation two years earlier. Many erroneous results, however, were found. Best agreement was found between laboratories which produced results on an interval scale ("quantitative"). The laboratories in this group used either x-ray diffraction, infrared spectrometry, or wet chemistry. This, however, did not apply to the wet chemistry kit Merckognost 11003, which was used by 24 of the 57 participating laboratories. A study of this kit by our laboratory led to several improvements including better calibration and reduced imprecision. General recommendations of how to present the analytical results to the clinician are given.
D002129:Calcium Oxalate / Q000032:analysis; D002130:Calcium Phosphates / Q000032:analysis; D003553:Cystine / Q000032:analysis; D005188:False Negative Reactions; D005189:False Positive Reactions; D006801:Humans; D008274:Magnesium / Q000032:analysis; D017616:Magnesium Compounds; D008722:Methods; D010710:Phosphates / Q000032:analysis; D011786:Quality Control; D011933:Reagent Kits, Diagnostic; D013055:Spectrophotometry, Infrared; D000069877:Struvite; D014527:Uric Acid / Q000032:analysis; D014545:Urinary Calculi / Q000378:metabolism*; D014961:X-Ray Diffraction
D002130:Calcium Phosphates; D017616:Magnesium Compounds; D010710:Phosphates; D011933:Reagent Kits, Diagnostic; D002129:Calcium Oxalate; D014527:Uric Acid; D003553:Cystine; D000069877:Struvite; D008274:Magnesium