We present the case of a 54-year-old woman, cholecystectomised at 23 years of age and with several episodes of residual choledocholithiasis resolved endoscopically as background of interest. The patient was admitted for epigastric pain radiating to the back, accompanied by nausea and vomiting, of hours' duration, without fever or dysthermic sensation. The patient had been discharged the previous day for residual choledocholithiasis that had resolved endoscopically, with no other pathological findings on endoscopic retrograde cholangiopancreatography (ERCP).
On examination, he presented pain in the right hypochondrium and epigastrium on palpation, with no signs of peritonism, and with a slightly distended abdomen. Laboratory tests showed leukocytosis with neutrophilia, hyperbilirubinaemia and mild elevation of transaminases, with normal amylase, as well as a marked elevation of 1 hour ESR. Parietal cell antibodies were positive and serum IgG4 was negative. Blood cultures were taken on admission and no microorganisms were isolated.
An ultrasound scan showed several space-occupying lesions suggestive of liver abscesses, so it was decided to complete the study with a magnetic resonance imaging (MRI) scan. This showed multiple lesions in both hepatic lobes, between 1 and 7 centimetres in diameter, hyperintensely ill-defined in T2-weighted sequences with fat suppression, and with homogeneous or peripheral enhancement during the dynamic study with intravenous contrast, thus being compatible with hepatic abscesses. Dilatation of the main bile duct with repletion defects at the level of the distal common bile duct and common hepatic duct, together with a stenosis at the level of the hilar confluence, with no apparent cause and which had not been seen previously, was also observed. Ultrasound-guided percutaneous drainage was attempted, but was not possible due to the absence of significant liquefaction. With intravenous antibiotic treatment, the patient became asymptomatic and remained afebrile. A new follow-up MRI scan was performed, showing a significant reduction in liver lesions, but without being able to rule out a neoplastic origin, as well as an irregularity in the origin of the left hepatic branch, which raises the doubt of an inflammatory or tumoural origin, in addition to choledocholithiasis. An ERCP was performed, from which two microcalcifications were extracted, confirming stenosis of the left hepatic branch, and samples were taken for cytological study, which were negative for malignancy. Finally, it was decided to perform an ultrasound-guided biopsy of the lesions, without incident. Histological examination of the lesion revealed a proliferation of myofibroblastic cells with elongated nuclei and cytoplasm, positive for actin and desmin by immunohistochemical techniques. There was also an increased population of IgG4-positive plasma cells, in some areas exceeding 30 per high-magnification field, with an IgG4/IgG ratio greater than 40%. All these findings were suggestive of inflammatory liver pseudotumour of the lymphoplasmacytic type, probably related to IgG4-related systemic disease. In addition, damage to the bile duct and some concentric periductal fibrosis without IgG4 cells at that level were seen in the non-injured liver.

The patient, after receiving antibiotic treatment for possible superinfection of the lesions given the history of ERCP, was discharged with steroid treatment in a descending regimen, with a good clinical-radiological evolution.