Rare Enterohepatic Fistula in Crohn’s Disease: Case Analysis and Literature Synthesis

Introduction

Crohn disease (CD) is an inflammatory bowel disease that represents a growing challenge in the healthcare landscape, particularly in developed countries. This condition is characterized by its ability to affect any segment of the gastrointestinal tract, from the oral cavity to the perianal area, presenting a wide array of clinical manifestations. One of the hallmark features of CD is its transmural inflammation, which has profound implications for patient morbidity. This type of inflammation can lead to severe complications, including obstruction, formation of strictures, and the development of fistulous tracts. These complications not only complicate the disease’s clinical course but also significantly impact the quality of life of affected individuals [1].

Fistulous complications in CD, such as perianal, entero-enteric, rectovaginal, or entero-cutaneous fistulas, are not only common but are also deeply impactful on patient well-being and quality of life. The rarer instances of fistulas involving the intestine and solid organs, including the relatively more frequent enterosplenic and the rare enterohepatic fistula, highlight the disease’s unpredictable and severe nature [2–6]. Despite the scarcity of enterohepatic fistulas in the context of CD, their clinical significance cannot be overstated, as they exemplify the potential for CD to lead to rare and complex complications. Although enterohepatic fistulas are infrequently associated with CD, their presence underscores the diverse manifestations of this disease. The literature primarily documents enterohepatic fistulas arising from other conditions, such as pyogenic liver abscesses or hydatid cysts, often presenting with nonspecific symptoms that can delay diagnosis and treatment. The exploration of these cases within the broader context of CD emphasizes the need for vigilant diagnostic and therapeutic strategies to manage these complex presentations effectively [7–9].

This case report of a 59-year-old female patient with a hepatic abscess due to a rare enterohepatic fistula in the context of a long-term history of CD underscores the importance of considering CD in the differential diagnosis of gastrointestinal symptoms, regardless of their apparent rarity.

Case Report

A 59-year-old female patient with a known history of CD presented to the Emergency Department with persistent right-sided abdominal pain for 10 days. At the time of presentation, she was in the process of weaning off prednisone, following an acute flare of CD 6 weeks prior, alongside her usual regimen of budesonide and vedolizumab. Her medical history included a previous ileocecal resection and ileocolic anastomosis performed in 2017 to address CD-related ileoileal and ileosigmoid fistulas, with no subsequent abdominal surgeries required. Additionally, she had a history of angioimmunoblastic T-cell lymphoma, from which she had been in remission for 3 years following successful chemotherapy.

Upon admission, the patient reported no symptoms other than the abdominal pain, specifically noting the absence of fever, diarrhea, or hematochezia. Despite having received a course of antibiotics (metronidazole and ciprofloxacin) prescribed by her gastroenterologist, her symptoms persisted. Physical examination revealed tenderness in the right side of the abdomen, without signs of peritoneal irritation. Initial laboratory tests showed an elevated C-reactive protein level of 66 mg/L, but no leukocytosis, cholestasis, or cytolysis was observed.

A computed tomography (CT) scan identified a hepatocolic fistula with an associated 3–4 cm hepatic abscess in liver segment V (Figures 1, 2). Drainage was attempted in interventional radiology, yielding approximately 5 mL of putrid fluid, although initial efforts to place a drainage catheter were unsuccessful. Culture of the fluid isolated Streptococcus mitis, Klebsiella pneumoniae, and Enterobacter cloacae complex, prompting the initiation of targeted antibiotic therapy.

Subsequent follow-up with ultrasound 3 days later showed a persisting liver abscess, leading to the successful placement of a drainage catheter. Imaging during the procedure revealed that the fistulous tract seemed to directly communicate with the previous ileocolic anastomosis. Elective surgery was planned a month later. The patient was discharged on the tenth day after admission, with the drainage catheter in situ. In the interim, imaging studies showed resolution of the liver abscess, with the catheter in place (Figure 3).

The surgery involved a medial, supra-umbilical laparotomy and extensive adhesiolysis to access and visualize the ileocolic anastomosis, which was then medialized. The surgical approach was chosen based on the surgeon’s preference and in anticipation of extensive adhesions, given the patient’s past medical and surgical history. The previously placed drain was removed under direct visualization, revealing that the fistula seemed to have closed. Approximately 10 cm of the intestine surrounding the anastomosis was resected (Figure 4), followed by the creation of an ileotransverse re-anastomosis. No liver abnormalities were noted during the procedure, and the surgery proceeded without significant complications. Histopathology revealed a fistulous tract extending from the intestine around the anastomosis to the liver tissue (Figure 5). The patient had a non-granulomatous form of CD, which is present in about 60% of cases [10].

Postoperative care addressed a paralytic ileus and pneumonia, culminating in the patient’s discharge in good condition on postoperative day 10. A 2-month follow-up consultation was uneventful.

Discussion

Through the detailed exploration of a rare manifestation of CD, namely an enterohepatic fistula leading to a liver abscess, presenting with nonspecific symptoms such as abdominal pain, we aim to show one possible approach regarding diagnostic work-up, differential diagnosis, and treatment.

CD currently presents an ever-growing burden of disease worldwide. The epidemiology of CD reveals significant variability based on geographic location, environmental factors, genetic predispositions, and patient sex, with a slight predominance observed in females. This variability underscores the complex interplay between genetic susceptibility and environmental exposures in the pathogenesis of CD [11,12]. While historically more prevalent in North America and Europe, recent years have seen a notable increase in CD cases in rapidly developing regions, such as Asia, Latin America, and Africa. This trend may reflect changes in lifestyle and dietary habits associated with urbanization and economic development, pointing to potential environmental triggers. A global review highlighted Europe’s significant disease burden, with Germany reporting a prevalence of 322 cases per 100 000 inhabitants, indicating the need for enhanced awareness and resources dedicated to managing this condition [13].

The Montreal classification system has been instrumental in providing a standardized framework for classifying CD, distinguishing between 4 clinical phenotypes: non-stricturing and non-penetrating; stricturing; penetrating; and perianal disease. This classification aids in tailoring treatment approaches and prognostic assessments for individual patients. Penetrating CD, characterized by the presence of abdominal inflammatory masses, free perforation, and various fistula types, represents a particularly severe disease manifestation. Fistulas, affecting approximately 50% of patients within 2 decades of disease onset, pose significant management challenges due to their propensity to recur and the complexity of their surgical treatment [14].

The literature on CD complicated by enterohepatic fistulas specifically, however, is sparse, with only a couple of case reports shedding light on the clinical management and outcomes of such a rare presentation (Table 1). Among these, Van Backer and Lee [15] detailed the case of a 32-year-old female patient with a long-standing history of CD who experienced abdominal pain and fever during her third trimester of pregnancy. A CT scan revealed terminal ileitis adhering to the right liver lobe and a hepatic abscess within the same region. Initial conservative management with percutaneous drainage and antibiotics was temporarily successful; however, the patient developed a recurrent abscess, necessitating elective laparoscopic intervention a month later. This surgical approach included a small bowel resection and marsupialization of the abscess cavity. Notably, the hepatoenteric fistula was not identified on preoperative imaging but was discovered intraoperatively.

In another instance, Rickes et al reported the case of a 25-year-old male patient with CD presenting with fever and chills. Ultrasound and endosonography revealed a large hepatic abscess and a fistulating ulcer in the duodenum. Remarkably, a significant amount of pus from the abscess was drained directly into the small intestine through the fistula during endosonography. The team opted against further interventional procedures, instead treating the patient with antibiotics and infliximab, achieving complete remission within 4 weeks. This case illustrates the potential for conservative treatment to result in full recovery in certain contexts [16].

In our case, postoperative histopathology confirmed the connection of the fistulous tract with the old anastomosis, ultimately raising the possibility of a different etiology altogether: an anastomotic leak covered by the liver, slowly evolving toward a liver abscess, which were connected to one another by a fistulous tract. Furthermore, the intraoperative discovery of a completely regressed fistula in our patient raises an intriguing consideration: the possibility that conservative treatment alone might have sufficed, similar to what Rickes et al reported [16]. This revelation underscores the complexity of CD management, in which imaging studies may not always reveal the full extent of disease-related complications. Conversely, some fistulas elude detection through standard imaging techniques and are only identified during surgical exploration.

These cases exemplify the unique pathogenesis and clinical course of the same diagnosis and underscore the critical importance of early diagnosis in managing CD-related enterohepatic fistulas, a task complicated by the often nonspecific nature of the symptoms. Ultrasound serves as the initial diagnostic tool of choice for identifying liver abscesses, with additional imaging modalities, such as CT or magnetic resonance imaging, being valuable when fistulation is suspected. Depending on the localization, endosonography can provide detailed insight into the extent of the fistula system, offering essential information for determining the most appropriate management strategy.

Given the rarity of this condition, there are no established treatment guidelines, and the choice between operative and non-operative management must be made on a case-by-case basis. Available case reports suggest that conservative treatment can be effective in some scenarios. If an abscess is present, drainage is typically considered the first line of intervention, followed by close surveillance and follow-up imaging to tailor the treatment plan as needed. This approach appears applicable across all CD-related fistulas between the intestine and solid organs, including the liver and spleen. The decision on whether to proceed with surgery and the choice between open and laparoscopic techniques depends on the patient’s profile and surgical history, with both approaches having demonstrated success in the reported cases [2–9].

These narratives not only demonstrate the variability in clinical presentations and outcomes associated with CD-related enterohepatic fistulas but also emphasize the necessity for a multidisciplinary approach to care, integrating the expertise of gastroenterologists, surgeons, radiologists, and pathologists, to navigate the challenges posed by this multifaceted disease [17].

Conclusions

Enterohepatic fistulas represent a particularly rare and challenging complication of CD, highlighting the complex nature of this condition. Our case illustrates the effective resolution of such a complication through an integrated approach that combined initial conservative management with subsequent elective surgery. In the absence of formal guidelines, the application of general surgical principles and the necessity for a highly personalized and multidisciplinary treatment strategy are imperative. This tailored approach is crucial for navigating the unique trajectory of each patient’s disease to achieve the best possible outcome.