Isolated elevated aspartate aminotransferase in an asymptomatic woman due to macro-aspartate aminotransferase: A case report

Table 1 Laboratory data in the clinic

Parameter	Result (normal range)	Parameter	Result (normal range)
AST in U/L	89.5 (13.0-35.0)	WBC as × 109/L	4.49 (3.5-9.5)
ALT in U/L	16.1 (7.0-40.0)	RBC as × 109/L	4.22 (3.8-5.10)
GGT in IU/L	12.6 (7.0-45.0)	Hemoglobin in g/L	123 (115-150)
ALP in IU/L	47.6 (35.0-100.0)	Platelets as × 109/L	187 (125-350)
ACHE in IU/L	7194 (4300-12000)	Neutrophils as × 109/L	2.69 (1.80-6.30)
TP in g/L	74.9 (65.0-85.0)	Lymphocytes as × 109/L	1.41 (1.10-3.20)
ALB in g/L	44.9 (40.0-55.0)	Monocytes as × 109/L	0.32 (0.10-0.60)
GLB in g/L	30.0 (20.0-40.0)
TBIL in μmol/L	9.4 (6.8-30.0)
DBIL in μmol/L	2.8 (0.0-8.6)	CHOL in mmol/L	4.39 (2.6-6.0)
IBIL in μmol/L	6.6 (5.1-21.4)	TG in mmol/L	0.62 (0.28-1.80)
Enzyme parameter
CK in U/L	67 (40-200)	Virology test
CKMB in U/L	7.2 (0.0-25)	Anti-HAV-IgM	- (-)
LDH in U/L	161 (120-250)	Anti-HEV-IgM	- (-)
α-HBDH in U/L	116 (78.0-182.0)	HBsAg	- (-)
MAO in U/L	3.4 (0.0-12.0)	Anti-HBsAb	+ (-)
AFU in U/L	21 (3.0-40.0)	HBeAg	- (-)
AMY in U/L	90 (1-135)	Anti-HBeAb	- (-)
LPS in U/L	46 (5.6-51.3)	Anti-HBcAb	- (-)
		Anti-HCV	- (-)
Immunological test		Anti-HIV	- (-)
Anti-dsDNA	- (-)	Anti-TP	- (-)
Anti-M2	- (-)
Anti-gp210	- (-)
Anti-SP100	- (-)	Liver metabolism test
Anti-SSA-52/Ro52	- (-)	CER in g/L	0.28 (0.2-0.6)
Anti-Sm	- (-)	SI in μmol/L	15.6 (7.8-32.2)
Anti-nRNP/Sm	- (-)	SF in μmol/L	43.5 (10-120.0)
Anti-LKM	- (-)	TIBC in μg/L	62.0 (50.0-70.0)
Immunoglobulin A in g/L	2.60 (0.7-4.0)
Immunoglobulin G in g/L	15.1 (7.0-16.0)
Immunoglobulin M in g/L	0.90 (0.4-2.3)
Complement C3 in g/L	1.31 (0.9-1.8)

AST: Aspartate aminotransferase; ALT: Alanine aminotransferase; GGT: γ-glutamyltransferase; ALP: Alkaline phosphatase; ACHE: Acetylcholinesterase; TP: Total protein; ALB: Albumin; GLB: Globulin; TBIL: Total bilirubin; DBIL: Direct bilirubin; IBIL: Indirect bilirubin; CK: Creatine kinase; CKMB: Creatine kinase isoenzymes; LDH: Lactate dehydrogenase; α-HBDH: α-Hydroxybutyrate Dehydrogenase; MAO: Monoamine oxidase; AFU: α-L- Fucosidase; AMY: Amylase; LPS: Lipase; Anti-dsDNA: Anti-double strand DNA antibody; Anti-M2: Antimitochondrial antibody 2; Anti-Sm: Anti-smooth muscle antibody; WBC: White blood cells; Anti-LKM: Anti liver and kidney microsomes antibody; WBC: White blood cell; RBC: Red blood cells; CHOL: Cholesterol; TG: Triglyceride; anti-HCV: Anti-hepatitis C virus antibody; anti-HIV: Anti-human immunodeficiency virus antibody; Anti-TP: Anti-Treponema pallidum; CER: Ceruloplasmin; SI: Serum iron; SF: Serum ferritin; TIBC: Total iron binding capacity.

Table 2 Precipitation with polyethylene glycol

	AST origin	AST DIL1/2	AST PEG	PPA (%)	AST recovery (%)
Patient	71.8	38.9	1.4	96.4	3.60
Control 1	229	121.7	49.8	59.1	40.9
Control 2	68	31	17.7	42.9	57.1

Polyethylene glycol precipitation (PEG): 25% PEG centrifuged at 3000 rpm of two control serum samples and samples from the patient with macro-aspartate aminotransferase (AST). AST origin: AST value of the original serum; AST diluted 1/2 (DIL1/2): AST value of serum DIL1/2 with phosphate-buffered saline; AST PEG: AST value after PEG precipitation. PEG-precipitable activity (PPA) = 100 × [(AST DIL1/2−AST PEG)/AST DIL1/2]; AST recovery = 100 × (AST PEG/AST DIL1/2).