Is there any Association of Distal Biliary Strictures with Acute Pancreatitis?
Departments of Gastroenterology and Hepatology, Dr Ziauddin University Hospital, Karachi, Sindh, Pakistan
Department of Gastroenterology, Dr Ziauddin University Hospital, Karachi, Sindh, Pakistan
Departments of Gastroenterology and Hepatology, Dr Ziauddin Hospital Clifton Campus, Karachi, Sindh, Pakistan
Department of Hepatobiliary and Transplant Surgery, Dr Ziauddin Hospital Clifton Campus, Karachi, Sindh, Pakistan
Department of Emergency Medicine, Dr Ziauddin University Hospital, Karachi, Sindh, Pakistan
Department of Medicine, Dr Ziauddin University Hospital, Karachi, Sindh, Pakistan
Manesh Kumar, Departments of Gastroenterology and Hepatology, Dr Ziauddin University Hospital, Karachi, Sindh, Pakistan, Phone: +92 03133278149, e-mail: maneshkumar136.mk@gmail.comAbstract
Background and objective
This cross-sectional study aimed to determine the frequency of distal biliary strictures in biliary pancreatitis, their relation with clinical and biochemical characteristics, and possible associations as a precipitating factor.
Materials and methods
A total of 51 patients with biliary pancreatitis were assessed for distal common bile duct (CBD) strictures and stones. Demographic data, biochemical parameters, and imaging findings were analyzed. Comparative analyses were conducted to evaluate differences between patients with and without strictures or stones.
Results
The mean age of the cohort was 54.0 ± 16.72 years, with females comprising 58.8% of the population. Distal CBD strictures were detected in 54.9% of patients, more frequently in females (64.3%) compared with males (35.7%). Patients without strictures accounted for 45.1%, with an almost equal gender distribution (52.2% females and 47.8% males). The CBD stones were identified in 70.6% of cases, with a marginally higher frequency among females (52.8%). Comparative analyses between patients with and without strictures showed no statistically significant differences in amylase (p = 0.616), lipase (p = 0.531), total bilirubin (p = 0.674), alanine aminotransferase (p = 0.589), aspartate aminotransferase (p = 0.621), gamma-glutamyl transferase (p = 0.483), or alkaline phosphatase (p = 0.398). Similarly, no significant differences were observed between patients with and without CBD stones in amylase (p = 0.420), lipase (p = 0.471), total bilirubin (p = 0.545), or inflammatory markers such as C-reactive protein (p = 0.313). Among patients with strictures, 53.6% had concurrent CBD stones, compared with 91.3% of those without strictures (p = 0.005).
Conclusion
Distal CBD strictures were present in over half of the patients with acute biliary pancreatitis (ABP). The presence of CBD stones was less common in these patients. Strictures were more common in females. There is a possibility that the presence of stricture may itself lead to complete obstruction even without stone when plugged with sludge or microlithiasis, ending up in the building of back pressure and pancreatitis.
How to cite this article
Kumar M, Abbas Z, Gazder DP, et al. Is there any Association of Distal Biliary Strictures with Acute Pancreatitis? Euroasian J Hepato-Gastroenterol 2025;15(1):34–37.
Introduction
Acute pancreatitis, characterized by pancreatic inflammation, presents a considerable morbidity with an overall mortality of 2–10%, necessitating aggressive intervention. The multifactorial and complex pathogenesis of acute pancreatitis remains incompletely understood, but its clinical implications, including local complications (necrosis, pseudocyst formation, abscesses, and hemorrhage) and systemic effects (pleural effusion, adult respiratory distress syndrome, renal insufficiency, and multiorgan failure), demand intensive management in the first 1–2 weeks.1
The yearly incidence of acute biliary pancreatitis (ABP) ranges from 4.9 to 80.0 cases per 1,00,000 individuals, exhibiting distinct variations among different ethnic backgrounds. A higher incidence in women (69 vs 31%) and an age-related increase underline the importance of understanding the demographic factors influencing ABP.2 The bile ducts, crucial conduits connecting the liver to the small intestine, play a pivotal role in acute pancreatitis.3 Biliary etiology in this context is clinically significant due to its association with complications requiring intensive care, such as necrosis, pseudocyst formation, and multiorgan failure.
Benign biliary strictures (BBS), stenosis in the extrahepatic biliary system, emerge as critical elements in acute pancreatitis. These strictures are usually sequelae of acute pancreatitis.4 The clinical presentation of BBS varies based on etiology, location within the biliary tree, and degree of ductal narrowing.5 Accurate identification of suspected BBS requires a comprehensive approach, incorporating clinical history, imaging studies [computed tomography (CT) and/or magnetic resonance imaging (MRI)], and endoscopic findings. The involvement of a common channel in over 70% of acute pancreatitis patients underscores the role of transient or persistent ampullary obstruction in the pathogenesis of ABP.6
Establishing the presence of a distal common bile duct (CBD) stricture at the time of presentation with acute pancreatitis is crucial due to the potential need for invasive treatments like endoscopic retrograde cholangiopancreatography (ERCP).2 This intervention becomes especially pertinent in the context of complications, emphasizing the importance of early and accurate diagnosis. This study aimed to determine the frequency of distal biliary strictures in biliary pancreatitis, evaluate their role in the induction of pancreatitis, and study the clinical and biochemical characteristics of these patients.
Materials and Methods
This was a cross-sectional study conducted over 6 months, from February 2024 to July 2024, following approval from the Ethical Review Committee. A total of 51 consecutive patients were recruited. Patients were included if they had biliary pancreatitis confirmed by at least two of the following criteria: symptoms consistent with pancreatitis (e.g., epigastric pain), serum amylase or lipase levels elevated to at least three times the normal limit, and radiological evidence of biliary pancreatitis identified on CT or MRI. A baseline abdominal ultrasound was performed for all patients, and if further clarification was needed, a CT scan or magnetic resonance cholangiopancreatography (MRCP) was conducted to confirm the diagnosis and assess for CBD dilation, gallbladder stones, or strictures. Exclusion criteria encompassed patients with other causes of pancreatitis, such as alcoholic or autoimmune pancreatitis, as well as those with chronic pancreatitis, malignancies, or pregnancy.
Data collection involved clinical evaluations, laboratory investigations, and imaging studies. Relevant laboratory parameters included serum amylase, lipase, liver function tests, and inflammatory markers. Imaging studies, including abdominal ultrasounds and MRCP, were used to confirm the presence of CBD strictures, stones, or dilatation. Medical histories were documented to ensure eligibility and exclude confounding factors.
The data were analyzed using Statistical Package for the Social Sciences. Descriptive statistics were used to summarize demographic and clinical variables, with categorical variables presented as frequencies and percentages and continuous variables as means and standard deviations. Correlation analyses were employed to explore relationships between variables, with results organized into tables and charts for clarity. The sample size was initially calculated as 37 using Raosoft software, with an error margin of 5% and a confidence level of 95%.
Results
In this cross-sectional study, we analyzed 51 patients diagnosed with biliary pancreatitis to investigate the frequency of distal biliary strictures and associated clinical characteristics (Table 1). The average age of the patients was 54.08 ± 16.72 years, with a slightly higher prevalence among females (58.8%) compared with males (41.2%). More than half of the patients (54.9%) had distal CBD strictures, predominantly observed in females (18 out of 28) compared with males (10 out of 28). Those without strictures accounted for 45.1% of the study population, with a nearly equal gender distribution (male: 11 and female: 12). The presence of CBD stones was noted in 70.6% of the patients, with a slightly higher distribution among females (19 out of 36) compared with males (17 out of 36). Patients without CBD stones represented 29.4% of the sample, with a higher proportion of females (11 out of 15) than males (4 out of 15).
| Variable | Value |
|---|---|
| Age (years) | 54.08 ± 16.72 |
| Male | 21 (41.2%) |
| Female | 30 (58.8%) |
| Distal CBD stricture | |
| Yes | 28 (54.9%) |
| Male | 10 (35.71%) |
| Female | 18 (64.28%) |
| No | 23 (45.1%) |
| Male | 11 (47.2%) |
| Female | 12 (52.1%) |
| CBD stones | |
| Yes | 36 (70.6%) |
| Male | 17 (47.22%) |
| Female | 19 (52.77%) |
| No | 15 (29.4%) |
| Male | 4 (26.66%) |
| Female | 11 (73.33%) |
| Amylase | 1856.9 ± 208.7 |
| Lipase | 3728.1 ± 493.4 |
| Total bilirubin | 2.98 ± 0.47 |
| ALT | 227.84 ± 42.6 |
| AST | 214.96 ± 56.1 |
| GGT | 402.16 ± 37.96 |
| ALP | 262.78 ± 21.2 |
| TLC | 10.67 ± 0.59 |
| CRP | 68.96 ± 13.12 |
Laboratory analysis is shown in Table 1.
A comparative analysis of patients with and without distal CBD strictures revealed no statistically significant differences across most biochemical markers as shown in Table 2. These findings suggest that the presence of a stricture does not significantly alter these biochemical parameters. Similarly, a comparison between patients with and without CBD stones showed no significant differences in biochemical markers, as demonstrated in Table 3. These results highlight that the presence of stones, like strictures, does not substantially impact the biochemical profile of these patients.
| Variable | With stricture | Without stricture | p-value |
|---|---|---|---|
| Amylase | 1,734.1 ± 265.2 | 2,006.3 ± 335.6 | 0.616 |
| Lipase | 3,868.4 ± 766.6 | 3,557.3 ± 588.5 | 0.842 |
| Total bilirubin | 3.09 ± 0.7 | 2.9 ± 0.52 | 0.583 |
| ALT | 209.8 ± 37.7 | 249.8 ± 83.6 | 0.484 |
| AST | 191.8 ± 48.1 | 243.2 ± 111.1 | 0.798 |
| GGT | 377.1 ± 38.0 | 432.6 ± 57.7 | 0.400 |
| ALP | 255.7 ± 50.8 | 276.3 ± 26.6 | 0.798 |
| TLC | 10.8 ± 0.9 | 10.5 ± 3.6 | 0.596 |
| CRP | 77.2 ± 21.4 | 58.9 ± 13.2 | 0.399 |
| Variable | With stones | Without stones | p-value |
|---|---|---|---|
| Amylase | 1,768.7 ± 257.7 | 2,068.5 ± 355.1 | 0.420 |
| Lipase | 3,500.3 ± 616.9 | 4,274.9 ± 801.5 | 0.342 |
| Total bilirubin | 3.2 ± 0.6 | 2.4 ± 0.71 | 0.278 |
| ALT | 204.8 ± 33.8 | 283.2 ± 122.1 | 0.828 |
| AST | 151.3 ± 23.4 | 367.9 ± 180.5 | 0.556 |
| GGT | 434.3 ± 47.4 | 325.0 ± 58.4 | 0.269 |
| ALP | 265.3 ± 22.2 | 256.8 ± 50.1 | 0.380 |
| TLC | 11.5 ± 0.68 | 8.7 ± 1.0 | 0.067 |
| CRP | 77.3 ± 16.6 | 61.0 ± 21.0 | 0.402 |
The distribution of patients with strictures and stones is depicted in Figure 1. Among patients with strictures, 15 (53.6%) also had stones, while 13 (46.4%) did not. Conversely, among those without strictures, 21 (91.3%) had stones, and only 2 (8.7%) did not (p-value = 0.005 by Fisher exact test). This distribution is the complex interplay between strictures and stones in biliary pancreatitis.
Discussion
The findings of this study provide important insights into the relationship between distal biliary strictures, CBD stones, and acute pancreatitis. Distal CBD strictures were prevalent in more than half of the studied cases, with a marked female predominance.1,6,7 Acute biliary pancreatitis is usually caused by gallstones obstructing the pancreatic duct or the ampulla of Vater. However, if a distal stricture is already present, the stricture itself may cause the obstruction, reducing the likelihood of concurrent stones. This could explain why, in patients with strictures, fewer had stones because the stricture itself is the culprit. We postulate that the presence of a stricture might impede the passage of sludge or microliths. Each time the sludge passes, it could leave inflammation leading eventually to a stricture. Further passage of sludge completes the obstruction transiently, leading to pancreatitis.8,9
It is known that choledochal cysts cause strictures and pancreatitis in a child, suggesting that structural abnormalities can lead to strictures and pancreatitis. So congenital or acquired strictures could be independent factors leading to pancreatitis without stones.10–12 The statistical significance (p = 0.005) suggests that the association between strictures and the absence of stones is not random. It is also known that microlithiasis or sludge may cause pancreatitis, which might not be detected as stones. Distal CBD strictures are the results of inflammation due to repeated passage of sludge or microliths. Eventually, sludge or microstone plugs the narrowed lumen, completing obstructive and building up the back pressure. Conversely, in patients without strictures, pancreatitis is more likely caused by stones, hence the higher percentage of stones in that group.
In terms of clinical implications, this finding could affect management. For instance, in patients with pancreatitis and distal CBD strictures but no stones, endoscopic sphincterotomy might be sufficient to relieve the obstruction. Whereas in those with stones, ERCP and stone removal would be standard. The study's results support the idea that different etiologies (stone vs stricture) exist for pancreatitis, necessitating tailored treatments.
The lack of statistically significant differences in biochemical markers, such as amylase and lipase, between patients with and without strictures challenges traditional assumptions. While strictures and stones are well-known contributors to the pathogenesis of biliary pancreatitis, these findings suggest that their impact on systemic biochemical disturbances might be limited. This aligns with newer perspectives in pancreatitis research, emphasizing the systemic inflammatory response rather than local anatomical factors as the primary driver of disease severity. Interestingly, C-reactive protein (CRP) levels, a known marker of systemic inflammation, were slightly elevated in patients with stones, although this did not reach statistical significance. This trend echoes findings from recent studies, suggesting that CRP might serve as an early indicator of biliary complications in pancreatitis, warranting further investigation.13
Imaging remains a cornerstone in the diagnosis and management of biliary pancreatitis. The role of advanced imaging techniques, such as MRCP and endoscopic ultrasound, has grown in recent years, enabling better characterization of strictures and stones.14,15 These tools, when integrated with biochemical and clinical findings, could enhance diagnostic accuracy and guide therapeutic interventions. Early intervention, particularly through ERCP, has proven pivotal in managing biliary complications, including strictures and stones. Recent advancements in ERCP techniques and adjunctive therapies, such as sphincterotomy, stent placement, and lithotripsy, have further improved outcomes for these patients.16,17
Conclusion
This study highlights the significant prevalence of distal CBD strictures and stones among patients with biliary pancreatitis, with strictures present in 54.9% of cases and stones in 70.6%. Notably, these conditions were more prevalent among female patients. Despite this high prevalence, the presence of strictures or stones did not result in statistically significant differences in biochemical markers, such as amylase, lipase, bilirubin, or liver enzymes. The absence of CBD stones in many patients with distal CBD strictures implies that the presence of such strictures is itself an etiological factor causing pancreatitis. These strictures are formed because of inflammation due to repeated passage of sludge. There is a possibility that sludge or microliths, while passing through an already critically narrowed area, eventually completely obstruct the lumen leading to pancreatitis.