Targeted liver ultrasound performed by an expert is the pivotal imaging examination for low phospholipid-associated cholelithiasis

Low phospholipid-associated cholelithiasis syndrome (LPAC), a not uncommon cause of biliary problems and hospital admissions

BACKGROUND AND AIMS

Biliary diseases are a major source of morbidity and mortality for patients and a burden for the healthcare system. The genetic syndrome LPAC (low phospholipid-associated cholelithiasis) is a little known and rare entity whose treatment with bile salts avoids symptoms, admissions and the need for surgery. Our aim is to determine its incidence and characteristics in our center.

METHODS

Prospective study between February 2021 and September 2022. LPAC was diagnosed if (at least two): onset of biliary problems <40 years of age, recurrence of symptoms after cholecystectomy, ultrasound image of hepatolithiasis (multiple echoic foci, comet-tail images, hepatolithiasis with acoustic shadow). Demographic, clinical, genetic (analysis of MDR3 gene mutations) and ultrasound characteristics were analyzed, as well as their incidence in hospital admissions for biliary causes.

RESULTS

36 patients with LPAC were identified. Of these, 6 were among 237 admissions for biliary causes in the previous 9 months, with an incidence of 2.5% (95%CI 1.17-5.41). By age subgroup, the incidence was 16.7% in those admitted <40 years and 9.1% in those <50 years. Considering women only, the incidence was 21% in those admitted <40 years and 15.8% in those <50 years. All patients remained asymptomatic after treatment with ursodeoxycholic acid and there were no new admissions.

CONCLUSIONS

LPAC syndrome is not as uncommon as it may appear, especially in women <50 years of age admitted with biliary problems. Its correct diagnosis based on simple criteria would avoid a significant number of hospital admissions and unnecessary cholecystectomies.

Searching for low phospholipid associated cholelithiasis among patients with post-cholecystectomy biliary pain

INTRODUCTION

Low phospholipid associated cholelithiasis (LPAC) is associated with variants of the adenosine triphosphate-binding cassette subfamily B, member 4 (ABCB4) gene and is characterized by reduced phosphatidylcholine secretion into bile, impairing the formation of micelles and thus exposing bile ducts to toxic bile acids and increasing cholesterol saturation. LPAC is present in 1% of patients with gallstones and post-cholecystectomy pain is common in this group. LPAC is an under-appreciated cause of post-cholecystectomy pain. The aim of this study is to assess a cohort of patients with post-cholecystectomy pain to identify those with clinical features suggesting that further investigations for LPAC would be beneficial.

METHODS

A retrospective chart review was performed of the first 2 years of post-operative follow-up for all patients under 40 years of age undergoing cholecystectomy for symptomatic gallstones at a tertiary centre between January 2016 and December 2017.

RESULTS

258 patients under the age of 40 underwent a cholecystectomy. 50 patients (19.4%) reported abdominal pain post-cholecystectomy. Five patients (1.9%) fulfilled the criteria for suspected LPAC. Family history of gallstones was documented in 33 of 258 (12.8%) of cases. Obstetric history was obtained in 69 of 197 (35%) female patients. None of the five patients identified above who satisfied the criteria of LPAC had the diagnosis of LPAC considered by their treating clinicians.

CONCLUSION

LPAC is an under-recognized cause of post-cholecystectomy pain. Treatment can avoid long-term symptoms and complications. Clinicians should take a family history and obstetric history to alert them to the diagnosis of LPAC.