Acute pancreatitis is one of the leading causes of hospitalization with a gastrointestinal condition in the United States [1]. The incidence of acute pancreatitis ranges from 13 to 45 per 100,000 individuals per year. Over 270,000 hospital admissions annually are attributed to acute pancreatitis, which have increased by 15% over the past 10 years [1,2]. Gallstones remain the most common cause of acute pancreatitis, followed by alcohol consumption. These two causes account for 70% of cases [3]. Other causes include hypertriglyceridemia, medications, autoimmune diseases, surgical procedure (e.g., endoscopic retrograde cholangiopancreatography), trauma, infection, and genetic and idiopathic factors. Although most patients with acute pancreatitis have mild, self-limited diseases, 20% to 30% can have a severe course with life-threatening complications. Local complications include fluid collection (e.g., acute peripancreatic fluid collection, pancreatic pseudocysts, acute necrotic collection, and walled-off pancreatic necrosis) with or without infection and vascular conditions (e.g., splenic vein thrombosis and splenic pseudo-aneurysm); conversely, systemic complications include systemic inflammatory response syndrome (SIRS) and subsequent organ failures [4-6].

Spontaneous splenic hemorrhage (e.g., rupture and subcapsular hematoma) is rare yet an important complication of pancreatitis. The exact incidence and epidemiology have not been clearly defined in the literature. Given the anatomic proximity between the pancreatic tail and splenic hilum, the direct erosion of pseudocysts, extravasation of pancreatic enzymes, localized portal hypertension due to splenic vein thrombosis, and adhesions from recurrent pancreatitis are the proposed pathophysiology of splenic manifestations [7-9]. As the clinical presentations of splenic hemorrhage can be nonspecific, imaging studies, especially computed tomography (CT), are warranted for differentiation from other etiologies [10]. Hemodynamically stable patients can be managed conservatively with percutaneous drainage and splenic artery embolization [11]. In contrast, surgical intervention with splenectomy is required for hemodynamically unstable patients [12]. Early recognition and intervention are critical for optimal patient outcomes.

In this literature review, we present a rare case of spontaneous splenic rupture as a complication of acute pancreatitis and provide a review of the literature to describe the patient characteristics, associated pancreatitis etiology, clinical presentations, risk factors, diagnostic and treatment modalities, and outcomes.

A 49-year-old woman presented with a 3-day history of fever, generalized malaise, and worsening of severe, diffuse, acute-onset abdominal pain that was greatest felt in the left upper quadrant.

She had a history of three hospitalizations and one short observation stay for acute pancreatitis over a 4-month period. Her symptoms were classic for acute pancreatitis: abdominal pain with radiation to the back, elevated lipase level, and radiologic findings of acute pancreatitis involving the tail of the pancreas. She was treated conservatively following these events and recovered uneventfully, except for the persistence of intermittent left upper quadrant abdominal pain. The diagnosis was considered idiopathic, as she reported no significant alcohol consumption, trauma, new culprit medications, laboratory test result abnormalities, or imaging findings to suggest gallstone pancreatitis, hypercalcemia, or hypertriglyceridemia. On her second admission (approximately 8 weeks since the first admission), imaging revealed new peripancreatic (tail) fluid collection abutting the spleen and gastric fundus (Fig. 1A). On the third admission (approximately 6 weeks since the second admission), imaging revealed new acute splenic vein thrombosis, gastric varices, and splenomegaly in addition to the known peripancreatic fluid collection (Fig. 1B). The patient was started on anticoagulation with low-molecular-weight heparin bridged to a direct-acting oral anticoagulant (DOAC) after hematologist consultation. The international normalized ratio on DOACs ranged from 2.1 to 3.4. Diagnostic endoscopic ultrasound (3 weeks since the third admission and 3 days before the current admission) showed a 3-cm heterogeneous fluid collection in the pancreatic tail with an irregular ill-defined margin extending to the splenic hilum consistent with the known finding (Fig. 2). No mass lesion was identified. The pancreatic parenchyma in the head and body of the pancreas was within normal limits. The common bile duct and pancreatic duct were non-dilated with no filling defects. Several benign-appearing 1-cm lymph nodes were noted.

On arrival to the emergency department, the patient was hypotensive at a blood pressure of 75/45 mm Hg and tachycardic at a heart rate of 120 beats/min. The laboratory test results were remarkable for the lipase level (147 IU/L), white blood cell count (15×10³ /μL), Hb level (10 g/dL), creatinine level (1.6 mg/dL), and beta-hemolytic non-group A or B streptococcus bacteremia presence. Abdominal and pelvic CT showed acute-onset chronic pancreatitis with fluid collection along the pancreatic tail (not organized) that extended into the postero-inferior aspect of the spleen and known thrombosis of the splenic vein with portosystemic collaterals, gastric varices, and mild splenomegaly. She was initially treated with fluid resuscitation and vasopressor and antibiotic administration with initial improvement in clinical status. However, she developed acute shortness of breath, worsening abdominal pain (progressed to diffuse, severe, and constant pain), and distension the following day. Repeat CT showed splenic rupture with moderate hemoperitoneum and perisplenic hematoma (Fig. 3). Emergency laparotomy with splenectomy was performed successfully with an uncomplicated recovery. Pathology revealed multiple lacerated spleen fragments.

An extensive English-language literature search was performed until November 2018 in PubMed, Cochrane Database, MEDLINE, and Google Scholar to identify case reports and case series employing the following keywords: pancreatitis, splenic rupture, and splenic hematoma. Cases related to pseudo-aneurysm rupture, previous procedure or surgery, and abdominal trauma were excluded. The search yielded 19 case reports [13-31] and 5 case series [32-36]. However, we included one case with splenic artery pseudo-aneurysm, as it did not rupture and therefore was not considered as the cause of splenic hematoma [23].

Patient demographics, comorbidities, social history, clinical presentations, diagnostic modalities, pancreatitis etiology and complications, splenic rupture timing and management, and spleen histology were reviewed and are summarized in Table 1. For the review, a total of 28 cases, including our case, were considered appropriate to be included. We summarized the available literature in addition to our case in this article.

Atraumatic splenic rupture and hematoma are rare complications of pancreatitis but can cause detrimental consequences and even a fatal outcome. In this review of the literature, the patient characteristics, associated pancreatitis etiology, clinical presentations, related risk factors, diagnostic and treatment modalities used, and outcomes were identified.

The majority of the patients in this study were middle-aged men who presented with acute pancreatitis. The leading etiology was alcohol consumption (67.9%); however, idiopathic pancreatitis was also a common etiology (21.4%). There are multiple different scoring methods to estimate the severity of pancreatitis, including Ranson’s score, Acute Physiology and Chronic Health Evaluation II score, SIRS score, and Bedside Index of Severity in Acute Pancreatitis score. These scoring systems are complex and not routinely used. Most case reports did not assess severity as scores nor use uniform information to evaluate such. Therefore, the correlation between the severity of pancreatitis and spontaneous splenic rupture could not be investigated in this study. The common chief complaints included upper abdominal pain, left chest or hypochondrium pain, left shoulder pain, and referred back pain. Associated nausea or vomiting was also common. These presenting symptoms are not specific to acute pancreatitis nor splenic rupture. Laboratory tests and imaging studies are required to rule out other etiologies, including peptic ulcer disease, left-sided pneumonia, aortic dissection, and acute myocardial infarction.

Although the pathophysiology of splenic complications is incompletely understood, the close anatomical proximity between the spleen and the pancreas has been considered as a major contributor to splenic complications during the course of pancreatitis. The splenic artery and vein and pancreatic tail, which are all located in the lienorenal ligament, enter the splenic hilum. This close anatomical association may lead to splenic involvement (e.g., intra-splenic abscess, pseudocyst formation, infarction, hemorrhage, and rupture) with pancreatitis [9]. The direct erosion of pseudocysts or extravasation of pancreatic enzymes from a fluid collection is considered as one of the potential mechanisms of splenic rupture [7]. In fact, the majority of the patients demonstrated fluid collections around the pancreas, especially in the tail of the pancreas adjacent to the spleen. Most of the fluid collections had well-defined pseudocysts. Splenic vein thrombosis was also shown to be a common risk factor associated with splenic rupture in this study. Venous outflow obstruction caused by this thrombosis may induce localized hypertension and congestion within the splenic parenchyma [8]. More than 70% of the cases had either chronic pancreatitis or prior episodes of pancreatitis. Adhesions from recurrent pancreatitis are also one of the proposed mechanisms of splenic complications. Although there were multiple risk factors suggested in this study, risk factor calculations are not possible with our limited number of patients.

In most cases, splenic rupture or hematoma was diagnosed using contrast-enhanced CT. Results can be obtained rapidly, and the extent of splenic hemorrhage along with other complications, such as fluid collection or vascular involvement, can be assessed [10,37]. More than 90% of the ruptured cases were managed with laparotomy with splenectomy. All hematoma cases were treated with conservative management and minimally invasive procedures, including percutaneous drainage or splenic artery embolization. In this study, most patients fully recovered without complications. However, there were one mortality and three significant complications reported among the 28 cases (14.3%), which cannot be overlooked. A high degree of clinical suspicion for splenic hemorrhage is required for prompt diagnosis and appropriate management, which can lead to a better outcome.

Splenic hemorrhage is a rare but life-threatening complication of pancreatitis. The exact incidence is unknown, and our findings are based on case reports and case series, including 28 patients. The patients in this study were predominantly men with recurrent episodes of alcoholic pancreatitis. The presence of pancreatic fluid collection, splenic vein thrombosis with left-sided portal hypertension, and pancreatitis involving the tail of the pancreas are potential risk factors for splenic hemorrhage among these patients. However, risk factor calculations are not possible in our limited number of patients. A high degree of clinical suspicion for splenic hemorrhage for prompt diagnosis is required to achieve optimal outcomes. Contrast-enhanced CT remains the most comprehensive and sensitive diagnostic modality for splenic rupture. Explorative laparotomy with splenectomy remains the first-line management method for patients with splenic rupture; conversely, splenic embolization and supportive care remain the preferred strategy for patients with splenic hematoma. Prompt recognition and intervention for this adverse event have maintained the associated mortality low.