Torsion of Accessory Hepatic Lobe.

An accessory hepatic lobe is a rare congenital anomaly that can undergo torsion and present as an acute surgical emergency. A 5-year-old child admitted as acute abdomen, on laparotomy found to have torsion of accessory lobe of liver, is being reported.

INTRODUCTION

Accessory hepatic lobe (AHL) is an extremely rare anomaly. They usually present as small tongue-like projections from the surface of the liver, in the vicinity of the gall bladder fossa. They can rarely present as isolated lobes, either connected to the liver by a pedicle or having a separate mesentery containing blood vessels and bile ducts.[1] Most cases are asymptomatic. When pedunculated, AHL can undergo ischemic torsion and present as acute abdomen. In general, the diagnosis is made after laparotomy and histopathological confirmation.

CASE REPORT

A 5-year-old male child was admitted with severe abdominal pain, vomiting, and fever. Pain abdomen was mainly in the right upper quadrant. He gave no history of similar prior episodes. Vomiting was nonbilious and fever was high grade and intermittent. He had not passed stools for past 2 days. On examination, he was febrile, pulse rate was 116/min, abdomen was mildly distended, and tenderness was present over right hypochondrium, right lumbar, and epigastric regions. He had generalized guarding and rigidity. On digital per-rectal examination, formed stools were present. X-ray chest and abdomen revealed no air under diaphragm and the ultrasonography abdomen was not contributory. His blood investigations showed raised total count and leukocytosis. With diagnosis of peritonitis, he was taken up for laparotomy. Abdomen was explored with supraumbilical transverse incision. Omentum was found over the liver surface. Colon was dilated, no pus or fluid was found in the peritoneal cavity, and intestines and appendix were normal. On further exploration, a black purplish mass, about 5 cm × 3 cm × 2 cm, was found hanging from the undersurface of the right lobe of liver, with a short peduncle, which had undergone torsion [Figure 1]. Hemostatic sutures with 3–0 Vicryl were placed at the base of the peduncle, and the mass was excised. The child had an uneventful postoperative recovery. Histopathology confirmed hemorrhagic necrosis of otherwise normal hepatic tissue.

Figure 1

Operative photograph showing torsion of accessory hepatic lobe

DISCUSSION

An AHL is a rare congenital developmental anomaly. It is usually asymptomatic and is seen as an incidental finding at laparotomy. There are only a few reported cases of asymptomatic AHL.[23] Currently, there are two hypotheses of the mechanism of an AHL: (i) The embryonic liver curls outward and forms an accessory lobe during the embryonic stage of development or (ii) an accessory lobe arises from intra-abdominal hypertension caused by the development of the tunica muscularis recti and the enlargement of the liver.[4] An accessory liver is adjacent and attached to the liver by its own mesentery while an ectopic liver is one that is completely detached from the normal liver parenchyma. Older literature has described four types of accessory liver: Big AHL (>30 g), small AHL (<30 g), ectopic lobe with no liver connection, and microscopic accessory lobe in the gall bladder wall.[2] Classification can also be based on the biliary drainage and the presence or absence of a common capsule – Type I: The separate accessory lobe duct drains into an intra-hepatic bile duct of the normal liver; Type II: The separate accessory lobe duct drains into an extrahepatic bile duct of the normal liver; and Type III: The accessory lobe and the normal liver have a common capsule; the bile duct of the accessory lobe drains into an extrahepatic duct.[5]

AHL is difficult to diagnose before surgery. However, an increasing number of patients with AHL are diagnosed in the early stages or before surgery due to rapid advances in medical imaging equipment.[4] Symptomatic AHL has been reported in neonates, as well as in patients presenting late in the third decade of life, commonly from torsion.[36] The usual presentation is an acute abdomen, with right upper quadrant pain, with or without a palpable mass. Timely surgical intervention is warranted when an AHL undergoes torsion. Laparotomy can serve as the mainstay of diagnosis as well as treatment. Successful laparoscopic resection of AHL has also been reported. Till 2013, only 22 cases of AHL have been reported.[4]

FINANCIAL SUPPORT AND SPONSORSHIP

Nil.

CONFLICTS OF INTEREST

There are no conflicts of interest.