Acute pancreatitis with chylous ascites mimicking acute appendicitis: A rare case report

Abstract

Introduction and importance

Chylous ascites, characterized by the accumulation of lymphatic fluid in the peritoneal cavity, presents a significant diagnostic and management challenge, particularly in resource-limited settings.

Case presentation

We report a case of a 63-year-old female with acute abdominal pain who was initially diagnosed with acute perforated appendicitis. During open surgery, Chylous ascites was found with normal appendix and bulky pancrease with surrounding fluid accumulation. Drain was placed in lesser sac area and appendectomy was performed with drain placed in right iliac fossa. Recovery was uneventful.

Clinical discussion

Chylous ascites can be challenging to diagnose, especially in resource-limited settings. Laboratory analysis and imaging studies play a critical role in establishing the diagnosis, while conservative measures and invasive interventions, if necessary, comprise the treatment strategy.

Conclusion

Our case highlights the importance of considering chylous ascites as a potential differential diagnosis in acute abdomen cases. Accurate diagnosis and management can be particularly challenging in resource-limited settings, and increased awareness among clinicians and further research is necessary to improve outcomes for patients.

Highlights

• •Patient having right iliac fossa pain preceeded by epigastric pain should be investigated for other pathologies also with acute appendicitis.
• •We Present a rare case report of female patient presented with the symptoms of acute perforated appendicitis but later on exploration chylous ascites was the cause of peritonitis.
• •Laparoscopic approach is safe and can reduces morbidity postoperatively.

1. Introduction

The work has been reported in line with SCARE criteria [1].

Chylous ascites is a pathologic state characterized by the abnormal accumulation of a milky or creamy fluid in the peritoneal cavity [2]. This fluid is rich in triglycerides, and is a result of lymphatic system dysfunction caused by various factors, such as congenital abnormalities, trauma, inflammation, cirrhosis, or malignancy within the abdomen [3,4]. The clinical manifestations of chylous ascites are closely correlated with the extent of ascitic fluid accumulation within the peritoneal cavity. Rapid and excessive accumulation of the fluid can trigger an acute abdominal response, while patients with chronic disorders may better tolerate the same volume of ascites [5]. The symptoms displayed by patients with chylous ascites is directly proportional to the degree of ascitic fluid accumulation, with the abrupt onset of ascites causing acute abdominal distress and chronic cases being better tolerated. Pain localized to the right iliac fossa is a typical manifestation of the condition, attributed to the accumulation of chylous fluid in the right paracolic gutter, which can simulate the symptoms of acute appendicitis. In order to distinguish between the two pathologies, testing for specific inflammatory biomarkers, including IL6, CRP, and LBP, may be helpful [6]. While the identification of chylomicrons through lipoprotein electrophoresis remains the diagnostic gold standard for chylous ascites, obtaining this test can be challenging and time-intensive [7]. The incidence of chylous pancreatitis masquerading as acute appendicitis in the medical literature is exceedingly low. Herein, we report an uncommon case of chylous pancreatitis that mimicked acute appendicitis and provide an account of its management.

2. Case description

A 63-year-old female patient was admitted to the emergency department complaining of abdominal pain, nausea, vomiting, and abdominal distension. The patient reported that the pain began in the epigastric region 5 days prior and was sudden in onset, radiating towards the back initially but then shifting to the right iliac fossa for the last 2 days. The pain was described as sharp in nature and worsened with movement, but improved with rest and analgesics. The patient also experienced multiple episodes of vomiting and nausea after food intake. Abdominal distension started 2 days prior, with associated pressure symptoms throughout the abdomen. The patient had a medical history of diabetes and was taking oral anti diabetic medications. In the past, she had experienced multiple episodes of right upper quadrant pain and was diagnosed with cholelithiasis through ultrasound. Additionally, the patient had a history of hepatitis B virus infection, which was treated conservatively in the past.

Upon examination, the patient had a pulse rate of 90 beats per minute, a temperature of 99oF, and a blood pressure of 120/85 mmHg. The abdomen was distended with tenderness and rebound tenderness in the right iliac fossa, which raised the suspicion of acute appendicitis. Bowel sounds were audible. Following investigations, a complete blood picture showed a white blood cell count of 15.09 × 109/μl, hemoglobin level of 16.8 g/dl, platelets count of 383 × 109/μl, neutrophils at 78.5 %, and lymphocytes at 11 %. The electrolyte levels were normal. The amylase level was elevated at 1615 U/l, and creatinine was 3.08 mg/dl. Additionally, the patient tested positive for hepatitis surface antigen on a rapid test (ICT).

Supine abdominal X-ray did not reveal any abnormalities. However, an ultrasound showed hypoechoic shadows in the pancreatic region and a fluid collection in the right iliac fossa, with positive probe tenderness. Upon admission, a senior consultant decided to perform surgery under the suspicion of acute perforated appendicitis.

A lower midline incision was made to access the abdominal cavity, where a brownish milky fluid of about 300 ml was observed in the right iliac fossa. The appendix was normal grossly, but the presence of the milky color fluid raised the suspicion of perforated viscous. To rule out other abnormalites, the incision was extended above the umbilicus. The peripancreatic area was found to be bulky with surrounding inflammation of fats upon entering the lesser sac. To drain the fluid, drain was placed, one in the sub gastric region. Appendectomy was performed and another drain was placed in subcecal region (Shown in Fig. 1).The abdomen was closed in reverse order, and the patient was transferred to the High Dependency Unit (HDU) for conservative management of acute pancreatitis. A Computerized Tomography (CT) scan performed on the 3rd post-operative day after normalization of creatinine level, revealed an acutely inflamed bulky pancreas with a peripancreatic fluid collection and fat stranding (Fig. 2). The patient was discharged without any post-operative complication and advised to visit for follow-up after two weeks but the patient didn't show on follow up date.

Fig. 1.

CT abdomen and pelvis with pancreatic protocol (right iliac fossa region with drain in situ.

Fig. 2.

CT abdomen with pancreatic protocol showing bulky pancrease and peripancreatic fluid collections with drain in situ).

3. Discussion

Chylous ascites is a rare condition characterized by the leakage of lymphatic fluid into the peritoneal cavity, with a reported incidence of 1 in 20,000 hospitalized cases. Rapid accumulation of the fluid can result in symptoms and signs of acute abdomen, which may progress to a condition known as chylous peritonitis [8].

The pathophysiology of chylous ascites (CA) can be classified into three major categories, as outlined in previous studies [9]: The first category involves obstruction of the lymphatic flow, which causes leakage from dilated sub-serosal lymphatics. The second category involves exudation of lymph through dilated retroperitoneal vessels that lack valves, often due to a fistula, such as in congenital lymphangectasia. The third category involves acquired thoracic duct obstruction, which may occur as a result of surgery or trauma.

Chylous effusion is a known but uncommon complication of pancreatitis. Typically, pancreatitis, particularly the chronic form, leads to the development of chronic chylous ascites without presenting with acute abdominal pain in most reported cases [4]. In our case pancreatitis was the main cause.

The most commonly reported symptom in patients with chylous ascites is abdominal distension. Other clinical signs may include abdominal pain, anorexia, weight loss, edema, weakness, nausea, dyspnea, weight gain, lymphadenopathy, early satiety, fever, and night sweats. While it is less common, chylous ascites can also present with acute abdominal pain. [10]. Severe pain and a physical examination can lead to misdiagnosis of appendicitis, cholecystitis, mesenteric arterial embolism, or perforated viscus in cases of chylous ascites-related peritonitis. This was seen in a young adult with spontaneous chylous ascites-related peritonitis, as well as in a case reported by Lamblim et al. [11] and fang et al. [10]. In our case patient had symptoms of right iliac fossa pain, abdominal distention, fever and vomiting.

Identifying chylomicrons using lipoprotein electrophoresis of abdominal fluid is the gold standard for diagnosing chylous ascites, but its rarity makes diagnosis difficult and this test is not typically performed routinely [7]. CT can be helpful but due to acute emergency it is often missed in preoperative investigation [3]. In our case it was not done preoperatively due high level of creatinine.

Management of Chylous ascites from conservative to surgery. In acute settings where signs of acute abdomen are present, surgery is often considered and the pathology is found intraoperatively. But in subacute chylous ascites, total parental nutrition can be considered as management of choice [3,4,7]. In our case surgery was done due to acute abdomen signs and symptoms.

The selection of surgical approach for the treatment of chylous ascites is ultimately determined by the surgical team in accordance with current guidelines. Laparoscopic intervention, which can serve both diagnostic and therapeutic purposes, is associated with reduced postoperative morbidity compared to traditional open surgery [3]. In the present case, open surgery was chosen over laparoscopic surgery due to the unavailability of instruments in emergency settings.

Limitation of this case report is we didn't capture intraoperative findings and we lost the sample of fluid and follow up of patient after 2 weeks.

4. Conclusion

In conclusion Chylous ascites although a rare pathology, may presents as mimicking acute appendicitis. Early symptoms of epigastric pain shifting to right iliac fossa should raise suspicion of such pathology and proper workup should be done before deciding such cases to operate. Laproscopic approach in doubtful cases may be helpful in term of finding the pathology and postoperative morbidity.

Ethical approval

Study was approved by Institutional Review Board of Hayatabad Medical Complex accordance with declaration of Helsinki (2013).

IRB No: 1297

Date: 5th May 2023

Funding

No funding source or sponsor.

Author contribution

1. Zaryab Ali Shah (Main Author)

2. Komal Fatima (Co Author)

3. Hasnain Hamid (Co Author)

4. Muhammad Ilyas (Co Author)

5. Muhammad Nouman (Co Author)

6. Muhammad Zeb (Corresponding Author)

Contribution:

1. Manuscript Writing, Final Drafting

2. Data Collection, Proof Reading

3. Data Collection, Proof Reading

4. Data Collection, Proof Reading

5. Data Collection, Proof Reading

6. Final Drafting, Critical Analysis, Proof Reading.

Guarantor

Dr. Muhammad Zeb

Post Graduate Trainee at General Surgery Department, Hayatabad Medical Complex Peshawar, Pakistan.

drmzeb@gmail.com

Research registration number

None.

Conflict of interest statement

No conflict of interest.