Usefulness of ultrasonography to assess the response to steroidal therapy for the rare case of type 2b immunoglobulin G4-related sclerosing cholangitis without pancreatitis: A case report

Table 1 Results of laboratory investigation

Hematology		Biochemistry
WBC	6260 × 106/μL	TP	7.9 g/dL	IgG	1850 mg/dL
Neutro	49.3%	Alb	3.6 g/dL	IgA	457 mg/dL
Lymp	34.0%	BUN	18 mg/dL	IgM	42 mg/dL
Eos.	9.4%	Cre	1.1 mg/dL	IgG4	255 mg/dL
Bas.	0.5%	T-Bil	0.9 mg/dL	CEA	1.9 ng/mL
Mon.	6.8%	D-Bil	0.2 mg/dL	CA19-9	59 IU/mL
RBC	453 × 104 /μL	AST	75 IU/L
Hb	13.7 g/dL	ALT	77 IU/L
Ht.	40.5%	ALP	1060 IU/L
Plt.	11.7 × 104 /μL	LDH	222 IU/L
		γ-GTP	1160 IU/L
		ChE	167 IU/L
		Na	140 mEq/L
		K	4.2 mEq/L
		Cl	106 mEq/L
Coagulation		P	3.7 mg/dL
PT%	113%	Ca	9.4 mg/dL
PT-INR	0.93	CRP	3.9 mg/dL
APTT	28.4 s	FBS	90 mg/dL
		HbA1c	5.7%
		TG	90 mg/dL
		HDL-C	66 mg/dL
		LDL-C	79 mg/dL

WBC: White blood cell; RBC: Red blood cell; Hb: Hemoglobinopathy; Plt: Platelets; PT: Prothrombin time; APTT: Activated partial thromboplastin time; TP: Total Protein; BUN: Blood Urea Nitrogen; AST: Aspartate aminotransferase; ALT: Alanine aminotransferase; ALP: Alkaline phosphatase; LDH: Lactate dehydrogenase; GTP: Guanosine triphosphate; CRP: C-reactive protein; FBS: Fasting blood sugar; HbA1c: Hemoglobin A1c; TG: Triglyceride; HDL-C: High-density lipoproteincholesterol; LDL-C: Low-density lipoprotein cholesterol; IgG: Immunoglobulin G; CA19-9: Carbohydrate antigen 19-9.

Table 2 Representative findings of the imaging modalities for immunoglobulin G4-related sclerosing cholangitis

Modality	Findings	Miscellaneous	Ref.
US	Wall thickening of the bile duct, dilatation of intrahepatic bile duct	Not specific, low sensitivity
EUS	High sensitivity	Combined with fine needle aspiration	[17-20]
IDUS	High sensitivity and specificity, high-resolution, images of the duct wall	May differentiate from cholangiocarcinoma
CT	Wall thickness, dilatation, the thickened segment shows progressive homogeneous contrast enhancement, with more enhancement seen in the delayed phase	Combined with contrast enhancement for differential diagnosis
MRI/MRCP	Bile duct wall thickening with iso-hypointense signal on T2-weighted image	Assessment of biliary system
PET	Uptake of FDG in bile duct wall
ERCP	Useful for the classification of the types	Useful for the situations in which an intervention, like stent placement, and biopsy is needed

US: Transabdominal ultrasonography; EUS: Endoscopic ultrasonography; IDUS: Intraductal ultrasonography; CT: Computed tomography; MRI: Magnetic resonance imaging; MRCP: Magnetic resonance cholangiopancreatography; PET: Positron emission tomography; ERCP: Endoscopic retrograde cholangiopancreatogr.

Table 3 Usefulness of the imaging modality for immunoglobulin G4-related sclerosing cholangitis

Ref.	Modality	Use	Usefulness
Kobori et al[20]	US	Diagnosis follow up	Diagnosis, improvement after PSL
Matsumoto et al[15]	EUS	Diagnosis	Differential diagnosis from the cholangiocarcinoma
Swensson et al[18]	CT, MRI	Diagnosis	Differential diagnosis from the cholangiocarcinoma
Zhang et al[21]	Laboratory exams	Follow up	Response to PSL
Ohno et al[22]	Laparoscopy andIDUS	Diagnosis follow up	Symmetric circumferentially thickened wall (IDUS), discoloration with red lobular markings and multiple small depressed lesions
Naitoh et al[19]	IDUS, Histology	Diagnosis	Differential diagnosis from the cholangiocarcinoma
Graham et al[10]	Histology, radiologic features	Diagnosis	Differential diagnosis from the cholangiocarcinoma
Horiguchi et al[23]	IDUS, ERCP, laparoscopy	Diagnosis	Differential diagnosis from the cholangiocarcinoma
Shimizu et al[24]	EUS, IDUS, CT, MRCP	Diagnosis follow up	Diagnosis
Our case	US, EUS, ERCP, MRCP	Diagnosis, follow up	Diagnosis of isolated, type 2 IgG4-SC and response to PSL

US: Transabdominal ultrasonography; EUS: Endoscopic ultrasonography; CT: Computed tomography; MRI: Magnetic resonance imaging; IDUS; Intraductal ultrasonography; ERCP: Endoscopic retrograde cholangiopancreatography; PSL: Prednisolone.