Study of urinary interferon gamma-induced protein 10 (IP-10) and urinary soluble CD 25 (sCD25) as markers of lupus nephritis and their relation to histological class

Peer review under responsibility of Alexandria University Faculty of Medicine.

Available online 11 December 2018

Figures & data

Table 1 Demographic, clinical and laboratory characteristics of patients in different groups.

	Group A (Active nephritis) (n = 25)	Group B (Inactive SLE) (n = 20)	Group C (Control) (n = 20)	P value
Age (years)	27.96 ± 7.98	30.25 ± 10.05	24.70 ± 6.42	0.110
Female: Male	22:3	18:2	18:2	1.000
Duration of disease (years)	2 (0.08–15)	4.75 (1–15)	–	0.001^*
Creatinine (mg/dl)	2.7 (0.8–8)	0.8 (0.6–1.10)	0.85 (0.6–1.1)	<0.001^*
24 hr urine protein (gm/day)	3.2 (1–10)	0.1 (0.09–0.14)	0.10 (0.08–0.12)	<0.001^*
Anti-dsDNA (IU/ml)	323 (150–570)	21.5 (12–35)	–	<0.001^*
C3 (mg/dl)	38.68 ± 13.20	139.1 ± 23.60	140.2 ± 22.05	<0.001^*
C4 (gm/l)	0.08 (0.04–0.29)	0.26 (0.12–0.39)	0.27 (0.13–0.38)	<0.001^*
SLEDAI score	11 (5–14)	1 (0–2)	–	<0.001^*
Renal SLEDAI	12 (4–12)	–	–	–

Data were expressed in mean ± SD or in median (Min.-Max.).

* Statistically significant at p ≤ 0.05.

Fig. 1 Urinary IP-10 (pg/ml) and CD25 (ng/ml) levels in different groups. (a) Urinary IP-10 (pg/ml) levels in different groups. (b) Urinary sCD25 (ng/ml) levels in different groups.

Fig. 2 Correlation between urinary IP-10 (pg/ml) with different parameters.

Fig. 3 Correlation between urinary CD25 (ng/ml) with different parameters.

Table 2 Urinary levels of IP-10 (pg/ml) and CD25 (ng/ml) in different histological classes of renal biopsy.

	Class
	II (n = 2)	III (n = 7)	IV (n = 14)	V (n = 2)
Urinary IP-10 (pg/ml)	2414.5 (1855–2974)	3419 (2721–3684)	4259 (2098–5871)	3006 (2984–3029)
Urinary CD25 (ng/ml)	24.85 (19.40–30.30)	39.8 (21.6–46.3)	55.5 (29.8–60.2)	27.25 (22.7–31.8)

Data were expressed in median (Min.-Max.).

Fig. 4 Relation between response to treatment with urinary IP-10 and urinary CD25 (Follow up).

Fig. 5 ROC curve for urinary IP-10 and urinary CD25 to diagnose active LN vs SLE without activity (Group A vs B).

Table 3 Agreement (sensitivity, specificity) for urinary IP-10 and urinary CD25 to diagnose active LN vs SLE without activity (Group A vs B).

	AUC	p	95% C.I		Cut off	Sensitivity	Specificity	PPV	NPV
			LL	UL
Urinary IP-10 (pg/ml(	0.950	<0.001^*	0.893	1.00	>2716	88.0	80.0	84.6	84.2
Urinary CD25 (ng/ml)	0.866^*	<0.001^*	0.764	0.968	>27.9	84.0	65.0	75.0	76.5

AUC: Area under a curve p value: probability value.

CI: Confidence Intervals *: Statistically significant at p ≤ 0.05.

PPV: Positive predictive value NPV: Negative predictive value.