CASE PRESENTATION
An 83-year-old male presented to the Tribhuvan University Teaching
Hospital (TUTH) with complaints of yellowish discoloration of the eyes
and abdominal discomfort, insidious in onset and gradually progressive
for a month. He had dark-colored urine, clay-colored stool and pruritus.
He also complained of anorexia, however, there was no significant weight
loss. He did not have a fever, abdominal pain, vomiting, abdominal
distension, gastrointestinal bleeding, and steatorrhea. There was no
past history of jaundice. The patient was hypertensive and was under
medication. He smoked 30 pack-years of cigarettes, and was a chronic
alcoholic. On examination, he was icteric, and the abdomen was soft and
non-tender without any organomegaly. Biochemical investigations showed
conjugated hyperbilirubinemia and abnormal liver function as outlined in
table 1. Hematological investigations, and serum amylase and lipase were
within normal limits.
The ultrasonography (USG) of his abdomen and pelvis showed a normal
scan. Contrast-enhanced computed tomography (CECT) scan of the abdomen
and pelvis was then carried out which revealed a significantly narrowed
lumen and mild thickening of the wall of the distal common bile duct
(CBD) at the entrance of the pancreatic head with dilatation of upstream
CBD and bilateral intrahepatic bile ducts (IHBDs). (Figure 1) These
findings carried us to the possibility of distal cholangiocarcinoma.
Therefore, the patient was further evaluated with serum levels of tumor
markers, carbohydrate antigen 19-9 (CA 19-9: 8 U/ml; normal range 0-37
U/ml) the carcinoembryonic antigen (CEA: 3.91 ng/ml; range 0-5ng/ml),
alpha fetoprotein (AFP: 5.24 ng/ml; range 10-20 ng/ml) which were within
normal range. An endoscopic retrograde cholangiopancreatography (ERCP)
was tried but the cannulation of the CBD failed due to a narrow lumen.
As a way out of this diagnostic riddle, the mass was suspected to be due
to IgG4-SC and the serum level of IgG4 was tested which was found to be
increased (more than 3.65 g/l). An oral steroid was started and the
patient showed significant clinical improvement within a month, which
further pointed the diagnosis toward IgG4-SC. The steroid was tapered
and stopped at the end of the three months. The clinical improvement of
the patient was accompanied by normalization of the liver functions
(table 1), and a subsequent abdominal CT scan which showed normal CBD.
The biopsy of the mass was planned during follow-up for the definitive
diagnosis. However, the low financial status of the patient and his
improvement with the steroid therapy curtailed its necessity. The
patient was followed up for three years during which he had no symptoms
of obstructive jaundice and abdominal pain. Also, abdominal CT scan and
liver function tests (table 1) that were repeated during the follow-up
were normal. Therefore, the higher level of serum IgG4, rapid
improvement with steroid therapy, normal level of tumor markers and no
recurrence of symptoms in the follow-up period of three years ruled-out
malignancy, and the diagnosis of IgG4-SC was made.