Diagnosis of accessory liver lobe torsion on diagnostic laparoscopy: an important differential in the absence of imaging findings

Accessory liver lobe (ALL) torsion is a rare differential for the acute abdomen that is usually first considered with positive imaging findings. We present a case of accessory liver torsion as a cause for an acute abdomen without findings on ultrasound. A 9-year-old female presented with 3 days of right sided abdominal pain. Her vitals were within normal limits, and the patient demonstrated voluntary guarding over the right lower quadrant and right flank on exam. Bloods showed a C-reactive protein of 25.6, however other bloods including a full blood count, kidney and liver function tests were unremarkable. An abdominal ultrasound was performed which showed reactive right iliac fossa lymph nodes and probe tenderness. The patient’s pain escalated and became generalised prompting a diagnostic laparoscopy which revealed a pedunculated dark red 5×6×1 cm mass on the posterior surface of the liver. This was resected via diathermy. Histology showed haemorrhagic necrosis with associated granulation tissue consistent with infarction. Post operatively, the patient developed a port site wound infection that was drained and treated with oral antibiotics. The patient is pain-free 2 months post operatively. It is important to consider torsion of the ALL as a differential diagnosis for the acute abdomen, even in the absence of definitive imaging findings.