尿路結石再発に関する臨床的検討 (4)尿中結晶と尿路結石再発について

Abstract

尿路結石238例と同数の非結石対照例を対象とした.早朝尿中に存在する結晶の大部分は蓚酸Ca結晶であり, その出現頻度は結石症例と非結石症例で差はみられず, 結石構成物質の尿中排泄と蓚酸Ca結晶の出現の間にも明らかな関係は認められなかった.結石症例の尿中蓚酸Ca結晶は非結石症例より有意に低い尿比重で発生し, 再発性または両側性結石症例では片側初発性結石症例よりも尿中蓚酸Ca結晶の出現頻度が有意に高かった.以上より, 尿中蓚酸Ca結晶の発生とその尿比重を観察することは結石再発の危険を予測する上で簡便かつ有用な臨床検査である

Relationship between stone formation and crystal formation in urine was studied. Crystals in the sediments of early morning urine in 238 stone formers and the same numbers of non-stone formers were examined by light microscopy. Almost all crystals found in the early morning urine were composed of calcium oxalate both in stone formers and in non-stone formers. The frequency of calcium oxalate crystal formation was slightly higher in stone formers than in non-stone formers, but, no significant difference was noted. On the other hand, the urine containing calcium oxalate crystals of the stone formers had significantly lower specific gravity than that of the non-stone formers. Calcium oxalate crystals in the urine were formed significantly more frequently in the recurrent or bilateral male stone formers than in male unilateral stone formers without previous stone history. Frequency of calcium oxalate crystal formation was not influenced by urinary excretion of calcium, oxalate, uric acid, phosphate and magnesium. These finding led us to the conclusion that it was clinically useful to measure urinary specific gravity in which calcium oxalate crystals were formed in predicting the risk of stone formation.