Lactobacillus plantarum liver abscess following ERCP: a case report and review

Abstract

Background

Lactobacillus plantarum is a probiotic. It has a positive effect on the intestinal flora, improving intestinal barrier function and regulating immune function. At present, it is clinically used to prevent or treat a variety of diseases. However, in recent years, serious infections caused by Lactobacillus plantarum have been reported. Endoscopic retrograde cholangiopancreatography (ERCP) is one of the main methods for managing biliary and pancreatic disorders. With the widespread application of ERCP, there are increasing reports of concurrent infections.

Case presentation

In this case, a 62-year-old female patient with pancreatic cancer developed chills and fever after undergoing ERCP and biliary stenting. She was diagnosed with a liver abscess, and the pathogenic bacterium identified was Lactobacillus plantarum, a rare instance of a probiotic causing disease.

Conclusion

This report describes the first case of a liver abscess caused by Lactobacillus plantarum following ERCP. This suggests that although Lactobacillus plantarum is a probiotic, it is risky for patients with anatomical disruptions, impaired mucosal barrier function, or immunocompromised status. Clinical applications of Lactobacillus plantarum should be treated with caution.

Introduction

Lactobacillus plantarum is a probiotic and a member of the genus Lactobacillus. It can function as an anaerobe or facultative anaerobe and is among the most widely recognized species within the genus. Lactobacillus plantarum belongs to the phylum Firmicutes, which is a major group of intestinal microorganisms [1]. It is found in a variety of foods (e.g., vegetables, fruits, legumes, dairy products, meat products, and wine, etc.), as well as in the mucous membrane environments (e.g., the oral cavity, stomach, intestines, and vagina, etc.) of humans and animals [2, 3, 4]. They are generally straight or curved rods, sometimes in the form of chains [5]. Lactobacillus plantarum is closely related to human life and is widespread not only in various foods but also in the gastrointestinal tract [6]. There has been an increasing number of trials exploring the therapeutic effects of Lactobacillus plantarum in various diseases [7]. However, there has also been a rise in reported cases of Lactobacillus plantarum infection.

ERCP is a commonly utilized surgical procedure for pancreaticobiliary diseases. Despite its high effectiveness, ERCP is frequently linked with various complications. With the global proliferation of ERCP, reports of its complications are steadily rising each year [8]. This article recounts a case involving a liver abscess caused by the intestinal probiotic Lactobacillus plantarum following ERCP.

Case presentation

A 62-year-old woman was admitted to the hospital presenting with chills, fever, and a temperature reaching 40 °C. She had been diagnosed with pancreatic cancer and biliary obstruction, indicated by yellow skin discoloration, five months ago. Endoscopic management, including ERCP with biliary sphincterotomy and stone extraction followed by placement of a biliary stent, was performed. One month ago, she was hospitalized due to abdominal pain, nausea, vomiting, and fever, and was subsequently diagnosed with a liver abscess. Blood and pus cultures revealed Candida albicans. After undergoing CT-guided percutaneous liver abscess catheter insertion and drainage, along with fluconazole treatment, she was discharged upon improvement. The patient had no history of diabetes or hepatitis, no recent travel or change in residence within the three months preceding onset of illness, and no history of smoking or alcohol consumption.

We conducted relevant examinations for the patient. Abdominal CT scan revealed (Fig. 1) a hypodense lesion in the hepatic caudate lobe. Abdominal ultrasound showed mixed echogenicity in the hepatic caudate lobe, measuring 7.4*5.7 cm. Laboratory tests exhibited leukocytosis with neutrophilia and elevated C-reactive protein levels (WBC: 13.6210^9/L, NE%: 79.40%, CRP: 174.39 mg/L), as well as increased hepatocellular enzyme levels (ALT: 58.41U/L, AST: 93.39U/L). Blood and pus cultures were positive for Lactobacillus plantarum. Given its probiotic nature, no drug susceptibility testing was performed, and empiric treatment with Piperacillin tazobactam was initiated. CT-guided percutaneous liver abscess puncture catheter drainage was performed, resulting in normalization of body temperature and reduction in abscess size. Subsequent abdominal ultrasound revealed mixed echogenicity in the hepatic caudate lobe, measuring 3.4*2.8 cm. The patient’s symptoms improved, and she was discharged from the hospital. However, three months later, the patient died due to fever and gastrointestinal bleeding.

Fig. 1

Abdominal CT showing a liver abscess (red arrow)

CT: computed tomography

Discuss

Liver abscess is a purulent lesion of the liver caused by bacteria, fungi, or microorganisms such as Entamoeba histolytica, which primarily invade the liver via the biliary route. Pyogenic liver abscess (PLA) is a prevalent clinical liver infection, constituting 80% of all liver abscesses. Pathogenic bacteria commonly associated with PLA include Escherichia coli, Klebsiella pneumoniae, enterococci, streptococcus, anaerobic bacteria, Staphylococcus aureus, among others, with Escherichia coli and Klebsiella pneumoniae being the predominant species [9]. In this case, both pus culture and blood culture of the liver abscess patient yielded Lactobacillus plantarum, a rare pathogen of liver abscesses. Lactobacillus plantarum is commonly acknowledged as a probiotic and is frequently utilized as a starter culture in various food fermentations, as well as in probiotic formulations [10]. It holds a Qualified Presumption of Safety designation from the European Food Safety Authority and is listed under the “generally recognized as safe” status by the United States Food and Drug Administration [11]. It also plays a large role in biomedicine, treating many diseases with little or no side effects, and can be used as a safe curative drug [12]. Therefore, Lactobacillus plantarum is presently utilized in the treatment of various diseases, including burn infections [13], severe acute pancreatitis [14], regulation of intestinal microbiota to enhance intestinal barrier function [15], and management of critical diseases. But is Lactobacillus plantarum really safe? We conducted a search for 19 cases of Lactobacillus plantarum over the past 50 years using Web of Science and PubMed databases(Table 1), Keywords included lactobacillus, lactobacillus Sepsis, lactobacillus plantarum, liver abscess, and endocarditis [16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33]. In our literature review, the median age of the 19 patients was 57 years (range:34–75 years), with a gender distribution of 11 males for every 7 females, except for one case with unclear gender. Lactobacillus plantarum was isolated from blood culture or tissue fluid culture in all 19 infected patients. Fever was reported in approximately 70% of patients, with most experiencing pain at the infection site. About 63% of patients showed symptom improvement after antibiotic treatment, which included penicillins, gentamicin, and imipenem. Among the cases, there were 8 instances of Lactobacillus plantarum endocarditis, 3 cases of sepsis, and single cases of pneumonia, throat infection, meningitis, arthritis, liver abscess, ostomy site abscess post-gastric cancer, acute acalculous cholecystitis complicated by peritonitis, and descending necrotizing mediastinitis. It is evident that under certain conditions, Lactobacillus plantarum can lead to multisystem infection. Some patients required surgery or abscess drainage based on their condition. Isobe et al.(1990) reported a case of Lactobacillus plantarum-associated liver abscess following percutaneous ethanol injection for liver cancer. In conclusion, Liver abscess following ERCP has not been previously reported. To our knowledge, this is the first report of Lactobacillus plantarum-associated Liver abscess following ERCP. ERCP is widely acknowledged as the primary treatment for various pancreaticobiliary diseases and is highly effective across multiple indications [34]. ERCP with Endoscopic sphincterotomy (ES) is generally considered a safe procedure, with expanding indications [8]. However, there are some complications that need to be addressed. Prior ES can lead to duodenal-biliary reflux by disrupting the barrier between the hepatobiliary system and duodenum. This disruption may facilitate bacterial colonization, cholangitis, or even liver abscess [35]. We consider that this patient developed a liver abscess and bloodstream infection due to infection with the intestinal Lactobacillus plantarum, with ERCP and stent implantation being significant contributing factors.

Table 1 Summary of 19 cases of Lactobacillus plantarum over the past 50 years

In summary, the patient in this case presented with multiple risk factors for liver abscess, including advanced age, recent ERCP, and underlying malignant tumors. Building upon previous case reports, it is evident that the Lactobacillus plantarum poses a significant risk for patients with disrupted anatomy, impaired barrier function, and compromised immune systems, potentially leading to fatal infections. Particularly in today’s context, where research on Lactobacillus plantarum is widely exploring its therapeutic potential across various diseases, this case highlights the elevated risk of severe infection associated with Lactobacillus plantarum in certain patients, including those undergoing ERCP, post-stenting, and those with advanced tumors. We share this case with the hope that it will serve as a valuable reference for our peers.

Conclusion

This report describes the first case of a liver abscess caused by Lactobacillus plantarum following ERCP. The patient in this case presented with multiple risk factors for hepatic abscess, including advanced age, recent ERCP with biliary stent placement, and underlying malignancy. In conjunction with previous case reports, probiotic treatments such as Lactobacillus plantarum are not completely safe in patients with anatomical disruption, abnormal barrier function, and immunocompromised patients, and it can lead to fatal infections. Especially in the current context, where Lactobacillus plantarum has been extensively studied for the treatment of various diseases, infections caused by this organism may become increasingly common. We report this case and hope that it will be a reference for many peers. Clinical applications of Lactobacillus plantarum should be treated with caution.