Relationship between serum adenosine deaminase levels and liver histology in autoimmune hepatitis

Table 1 General characteristics of patients with autoimmune hepatitis

Parameter	AIH (n = 52)
Mean age in yr	40.1 ± 12.8
Sex as female/male	37 (71.2)/15 (28.8)
Laboratory findings
ALT as × ULN	7.0 (IQR = 9.3)
AST as × ULN	6.2 (IQR = 9.1)
ALP as × ULN	1.3 (IQR = 1.7)
Total bilirubin as × ULN	0.9 (IQR = 1.6)
Albumin in gr/dL	3.8 (IQR = 0.8)
Serum IgG in gr/dL	2035 (IQR = 840)
Platelet counts as × 103/mm3	219.0 (IQR = 66.8)
INR	1.1 (IQR = 0.2)
Autoimmune serology
ANA	38 (73.1)
SMA	20 (38.5)
Anti LKM-1	1 (2)
Histological features
İnterface hepatitis
Mild	9 (17.3)
Moderate	18 (34.6)
Severe	25 (48.1)
Fibrosis score
0	6 (11.5)
1	9 (17.3)
2	11 (21.2)
3	16 (30.8)
4	10 (19.2)

Data are presented as n (%), unless otherwise specified. AIH: Autoimmune hepatitis; ALP: Alkaline phosphatase; ALT: Alanine aminotransferase; ANA: Antinuclear antibody; INR: International normalized ratio; IQR: Interquartile range; LKM-1: Liver kidney microsome type 1; SMA: Smooth muscle antibody; ULN: Upper limit of normal.

Table 2 General characteristics and adenosine deaminase levels of the study population

	AIH (n = 52)	Controls (n = 28)	P value
Age in years	40.1 ± 12.8	45.1 ± 10.7	0.080
Sex, F/M as n (%)	37 (71.2)/15 (28.8)	24 (85.7)/4 (14.3)	0.144
ADA level in U/L	25.4 ± 9.6	12.8 ± 2.2	< 0.001

ADA: Adenosine deaminase; AIH: Autoimmune hepatitis.

Table 3 General features and laboratory findings of autoimmune hepatitis patients according to inflammatory activity

	Interface hepatitis			P value
	Mild (n = 9)	Moderate (n = 18)	Severe (n = 25)
Age in years	39.3 ± 14.5	41.1 ± 11.0	39.7 ± 13.9	0.927
Sex, F/M	6-3	12-6	6-19	0.759
ALT as × ULN	3.9 (IQR = 1.6)	7.3 (IQR = 11.3)	10.9 (IQR = 12)	0.0321
Serum IgG in gr/dL	1810 (IQR = 745)	1955 (IQR = 570)	2390 (IQR = 1205)	0.0291
ADA in U/L	15.2 ± 3.5	23.1 ± 10.0	30.9 ± 7.0	< 0.0011
ADA > 20 U/L, n (%)	0	9 (50)	24 (96)	< 0.0011

¹Indicated statistically significant difference. ADA: Adenosine deaminase; AIH: Autoimmune hepatitis; ALT: Alanine aminotransferase; IQR: Interquartile range; ULN: Upper limit of normal.

Table 4 Receiver operating characteristic curve for adenosine deaminase level in diagnosis of severe interface hepatitis

Cut-off, U/L	AUC	SE	95%CI	Sensitivity	Specificity	PPD	NPD	P value
24.55	0.88	0.06	0.77-0.99	88	85.2	88.5	84.6	< 0.0011
25.25	0.88	0.06	0.77-0.99	84	88.9	85.7	87.5	< 0.0011

¹Indicated statistically significant difference. AUC: Area under the curve; NPD: Negative predictive value; PPV: Positive predictive value.