False positivity of gamma-glutamyl transpeptidase measurement in urine

Figures & data

Table 1. Mean values ± standard deviation for systemic blood pressure (SBP), UPC, creatinine clearance (CrC), and median values ± interquartile range for urinary GGT enzyme activity to urinary creatinine ratio (uGGT/uCr) of dogs from G1 and G2 at baseline (T0), 4 hours (T4), 24 hours (T24), and 48 hours (T48) after experimental administration of N. oleander.

		T0 (baseline)	T4	T24	T48
SBP	G1	142.33 ± 15.52	140.33 ± 13.20	126.33 ± 16.09	138.66 ± 18.21
	G2	139.33 ± 19.88	136.99 ± 16.66	131.99 ± 17.88	141.66 ± 19.12
UPC	G1	0.25 ± 0.17	–	0.20 ± 0.15	0.30 ± 0.19
	G2	0.25 ± 0.18	–	0.35 ± 0.19	0.46 ± 0.18
CrC	G1	1.43 ± 0.6	–	1.39 ± 0.56	1.08 ± 0.48
	G2	1.41 ± 1.02	–	1.04 ± 1.23	2.70 ± 0.98
Creatinine	G1	1.09 ± 0.21	1.12 ± 0.18	1.05 ± 0.14	1.09 ± 0.19
	G2	0.9 ± 0.2	0.91 ± 0.23	0.82 ± 0.2	1.0 ± 0.06
Urea	G1	39.76 ± 5.2	36.48 ± 8.17	36.78 ± 3.63	37.83 ± 5.73
	G2	40.96 ± 4.71	29.04 ± 4.62	35.3 ± 8.4	36.64 ± 7.75
uGGT/uCr**	G1	45.8 ± 26.8^a	149.3 ± 56.5^b	135.1 ± 67.3^b	33.9 ± 35.4^a
	G2	30.5 ± 17.7^a	156.7 ± 103.5^b	235.0 ± 243.1^b	77.1 ± 8.3^a

Notes: Mean values followed by different superscript letters in the same row are statistically different (p < 0.05).

**Median values ± interquartile range.

Figure 1. Graphical representation of urinary GGT enzyme activity to urinary creatinine ratio (uGGT/uCr) in healthy dogs (G1 = 5) and (G2 = 5) before and after administration of N. oleander. The uGGT/uCr ratio exhibited a significantly higher concentration at 4 and 24 hours compared to baseline (0 hours) and 48 hours (*p < 0.05).

Figure 2. Electron microscopy showed cells with well-defined brush border and basolateral membranes. ×2000.