The free radical oxidative damage urine
color test gives comparible results to laboratory tests in patients with Parkinson's. Laboratory validation
follows.
URINE MALONDIALDEHYDE ( MDA ) MEASURED IN PARKINSON DISEASE,
BY A FLUOROMETRIC AND A VISUALLY READ COLORIMETRIC ASSAY.
R. Hubbard, R. Iacono, J. Westengard, and
Schoonenberg Depts. of Path., and Neurosurg. Sch. Med., Loma Linda Univ., Loma Linda, CA
92350.
We have measured the urine MDA levels in 17 Parkinson disease (PD patients and
caregiver controls, by a fluorometric method (Conti et al., Clin. Chem. 37:1272,1991) and a one step visually
read colorimetric method adapted from Miksch et al., Anal. Chem. 53:2118,1981, which is available through
Vitaleaf Technologies, Irvine, CA. PD subjects and controls volunteered for the study while attending the 1999
Iocono Pallidotomy Reunion. They collected random midmorning urines and signed consent forms approved by the
Investigative Review Board, Loma Linda University. To compare the two methods a Spearman rank order correlation
coefficient 0.656 (p<0.0005) was computed. A one-way ANOVA with post hoc comparisons (Bonferroni) was
performed to compare the mean fluorommetric MDA levels across the 4 semi-quantitative levels of the
colorimetric method. The results showed that only the highest (level 3) compared to the lowest (level 0) were
significantly different (p<0,02). Blind repetition of the colorimetric assay showed a perfect match in the
reading for 27 of the 34 urine specimens. The seven non-matched results were within one level of matching. The
difference in MDA levels between patients and controls was significant when measured by either the fluorometric
(independent t-test, p=0.00005) or the colorimetric (Kruskal-Wallis, p=0.004) method.
|