Department of Surgical Gastroenterology, H. P. B. Surgery and Liver Transplantation, Bombay Hospital and Medical Research Centre, Mumbai - 400 020, India.
Address for correspondence: Dr. S. K. Mathur, Bombay Hospital and Medical Research Centre, 134, M.R.C. Bldg.; 1st Floor,12, Marine Lines, Mumbai-400 020, India.

Code Number: jp00010

Abstract:

A patient with a peripancreatic lymph node tuberculosis mimicking pancreatic pseudocyst is reported, which was diagnosed on exploration to be a tuberculous cold abscess. The patient responded to anti-tuberculous drugs after drainage of the cold abscess. (J Postgrad Med 2000; 46:33-34)

Key Words: Abdominal tuberculosis, pancreatitis, pancreatic pseudocyst, tuberculous lymphadenitis, cold abscess.

Isolated peripancreatic lymphnodal tuberculosis is very uncommon. It is a diagnostic challenge to the physician, because it mimics pancreatic head tumour or/abscess ¹ . Exploratory laparotomy with biopsy is often required to establish the exact nature of the lesion.

Case Report

A 26-years-old, non-alcoholic male patient presented with history of vague pain in epigastrium of one-year duration and jaundice associated with loss of appetite and loss of weight of about 15 kgs. Over last three months. There was no prior history of tuberculosis. Examination revealed mild icterus. Per abdominal and rectal examinations were normal.

Investigations: Haemogram showed haemoglobin to be 12.8 g/dl, white blood cell count 8,200/mm ³  and erythrocyte sedimentation rate of 55 mm at 1 hour S. Bilirubin was 2.9 mg/dl with direct of 2 mg/dl, Alanine aminotransferase 24 u/l, Aspartate aminotransferase 31 u/l and alkaline phosphatase 462 u/l, albumin 3.5 g/dl and globulin 3.4 g/dl, amylase 180 u/l. X-ray chest was normal. Ultrasound of abdomen showed mild hepatomegaly with mild dilatation of intra-hepatic biliary radicals, Common bile duct (CBD) was dilated measuring 9 mm in its lower part. Gall bladder was normal. Pancreas showed a cyst of 3.6 x 3-cm. diameter in the head of pancreas causing compression of terminal CBD. Pancreatic head was thick and enlarged with normal body and tail. Computerised tomography (CT) of abdomen revealed diffuse enlargement of pancreatic head with hypodense mass lesion of about 10 x 8 cm. in diameter extending from left infra-hepatic to retro pancreatic region causing obliteration of peripancreatic fat planes. The body and tail of pancreas and pancreatic duct were normal. It was reported as either infected pseudocyst of pancreas or pancreatic abscess. Endoscopic retrograde cholangio-pancreatography showed extrinsic compression of infra duodenal portion of lower CBD with proximal dilatation and normal pancreatic duct. CT guided fine needle aspiration (FNA) revealed thick purulent material, which on cytological examination showed only necrotic material without evidence of either tuberculosis or malignancy.

An exploratory laparotomy revealed multiple tubercles on omentum, gastrohepatic omentum, serosal aspect of gall bladder, pelvic parietal peritoneum, retroperitoneum overlying second part of duodenum. Liver was normal. Gall bladder was distended and tense. A 10 cm. x 10 cm. cold abscess containing caseating material and liquid pus was found extending from under surface of left lobe of liver (adherent to liver and lesser curvature of stomach) behind lesser omentum down across hepatoduodenal ligament, in retroduodenal portion of CBD and posterior aspect of head of pancreas. CBD dilated up to 2 cm. in supra duodenal portion. Infraduodenal retropancreatic portion of terminal CBD showed a 2-mm size communication between the abscess and CBD. Cold abscess was drained and cholecystectomy with choledochoduodenostomy over T-tube was done in view of terminal CBD stricture and gall bladder obstruction. Wall of abscess cavity where it was communicating with CBD was sutured after packing with a patch of cellulose mesh (Surgical). Post-operative recovery was uneventful. Histopathology confirmed the diagnosis of tuberculous lymphadenitis, with multiple granulomata of varying sizes showing caseation, Langhan's giant cells and epithelioid histiocytes. However, no acid-fast bacilli were detected.

Patient was started on four drug antitubercular regime and at follow up after six months, patient was asymptomatic.

Discussion

Tuberculosis of isolated peripancreatic lymphnodes is extremely rare. It more often occurs in association with pancreatic tuberculosis, which is also extremely rare ^2,3 . Pancreatic tuberculosis presents with wide spectrum of symptoms. These include upper abdominal pain, pyrexia of unknown origin, obstructive jaundice, mimicking pancreatic carcinoma, acute pancreatitis, pancreatic abscess refractory to antibiotics, massive gastrointestinal haemorrhage due to duodenal wall erosion, splenic vein thrombosis, chronic pancreatitis and non-specific symptoms with weight loss ^1-4 .

Contrast enhanced CT patterns correlate well with the pathologic features of tuberculous lymphadenopathy. In one major study on contrast enhanced CT images, reviewers made a correct diagnosis of tuberculosis in 94% of cases with a specificity of 95% and sensitivity of 92% ⁵ . Low density enlarged lymph nodes with immediate post contrast peripheral rim enhancement is quite classical of tuberculosis. Once imaging and FNA establish diagnosis, usually exploratory laparotomy is not required. However, often it may not be possible to establish a diagnosis just by a CT scan or FNA, as in the present case, where CT was reported as pancreatic abscess or infected pseudocyst and cytology was inconclusive. In such cases, exploratory laparotomy may be indicated to establish a diagnosis. Other indications for an exploration are secondary compression of nearby structures e.g. bile duct as in the present case or complications such as gastrointestinal bleed. Once explored, surgical procedure of choice for associated lower CBD obstruction is a choledochoduodenostomy, as was done in the present case. However, an endoscopic biliary stenting could be an alternative if the patient does not merit surgical exploration.

In conclusion, a peripancreatic cold abscess can mimic pseudocyst of pancreas. Provided diagnosis is established, anti-tuberculous chemotherapy with aspiration or pigtail drainage may be sufficient. Surgery should be reserved either to establish diagnosis or to deal with associated complications.

References

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Copyright 2000 - Journal of Postgradate Medicine