FT-IR Analysis of Urinary Stones: A Helpful Tool for Clinician Comparison with the Chemical Spot Test

Table 1

Chemical constituents of urinary stone (%) obtained using chemical spot test (a) and FT-IR analysis (b).

(a) Chemical spot test analysis

Components detected	Number	Frequency (%)
Oxalate	45/48	93.7
Calcium	39/48	81.2
Magnesium	16/48	33.3
Phosphate	14/48	29.1
Urate	9/48	18.7
Ammonium	7/48	14.5
Cystine	5/48	10.4
Carbonate	3/48	6.2

(b) FT-IR analysis

Components detected	Number	Frequency (%)
Calcium oxalate monohydrate	32/48	66.6
Carbonate apatite	16/48	33.3
Anhydrous uric acid	12/48	25.0
Calcium oxalate dihydrate	8/48	16.6
Dihydrate uric acid	2/48	4.1
Magnesium ammonium phosphate	2/48	4.1
Cystine	2/48	4.1
Atazanavir	1/48	1.0