Clinical Utility of Ammonia Concentration as a Diagnostic Test in Monitoring of the Treatment with L-Asparaginase in Children with Acute Lymphoblastic Leukemia

Table 4

The parameters assessing the ability of the mean value of the ammonia concentrations to recognize patients with low ASP activity in at least one examination (2 cut-off points, 95% CI in brackets).

	The mean value of the ammonia concentration
	24 hours after ASP administration		3 days after ASP administration
	≤46 𝜇mol/L	≤91 𝜇mol/L	≤20 𝜇mol/L	≤36 𝜇mol/L
Sensitivity	0.17 (0.04–0.41)	0.89 (0.67–0.99)	0.22 (0.06–0.48)	0.89 (0.67–0.99)
Specificity	0.99 (0.92–1.0)	0.70 (0.58–0.81)	0.99 (0.92–1.0)	0.70 (0.58–0.81)
Positive predictive value	0.75 (0.19–0.99)	0.46 (0.28–0.63)	0.80 (0.28–0.99)	0.46 (0.30–0.60)
Negative predictive value	0.82 (0.72–0.89)	0.96 (0.86–0.99)	0.83 (0.73–0.90)	0.96 (0.89–0.99)