Discussion
Retroperitoneal bleeding is a rare, but potentially life-threatening cause of abdominal pain. It is caused by a complication of femoral artery catheterization or other imaging procedures, pelvic/lumber trauma, oral coagulants, and aortic dissection.5Visceral aneurysm and dissection are the rare causes of retroperitoneal bleeding. The IPDA contributes to only 2% of visceral aneurysms.2 The mortality rate for ruptured IPDA aneurysms is approximately 30%, requiring early identification and treatment.4 Bleeding from the IPDA dissection has also been reported.2 The IPDA aneurysms are associated with celiac artery stenosis, atherosclerosis, infection, trauma, and pancreatitis. They were related to celiac artery stenosis in 60%-75% of cases.6 Celiac artery stenosis can be detected by contrast-enhanced CT or Doppler ultrasonography. Since celiac artery stenosis is found in approximately 7% of asymptomatic patients, the presence of typical symptoms, such as chronic abdominal pain (especially postprandial), nausea/vomiting, and mild weight loss, is needed for the diagnosis of CACS.7,8 The mechanism by which the celiac artery stenosis leads to the development of IPDA aneurysms is associated with the formation of arterial pancreatic arcade.9,10. The superior and inferior portions of the anterior and posterior pancreaticoduodenal arteries form a pancreatic arcade between the celiac artery and SMA. Celiac artery stenosis reduces blood flow to the pancreatic arcades, which increases blood flow and pressure in the IPDA from SMA, promoting the IPDA aneurysm or dissection formation.
In this case, the patient presented with severe abdominal pain, which led to the diagnosis of retroperitoneal hemorrhage. The patient had a celiac artery stenosis detected in CT scan, which we believe, was the cause of the PIPDA dissection. In addition, the patient had chronic, non-specific abdominal pain, which may be a symptom of CACS. Typical symptoms of CACS are chronic abdominal pain (especially postprandial), nausea/vomiting, and mild weight loss. In the present case, nausea, vomiting, and weight loss, which are typical symptoms of CACS, were not observed. The other possibility is that atherosclerosis may have caused the PIPDA dissection, not related to CACS, since dyslipidemia is an underlying disease in this case.
The patient had elevated liver enzyme levels, which resolved with treatment; however, the relationship between elevated liver enzyme levels and CACS or IPDA aneurysm/dissection has not been reported in previous literature. Our hypothesis is that blood flow to the liver originating from the celiac artery was reduced due to celiac artery stenosis prior to this episode, and as a result, blood flow from the SMA region to the liver was supplemented via the pancreatic cascade. In this patient, we believe that the PIPDA dissection reduced the total blood flow to the liver from the SMA region, causing transient liver ischemia.
The first-line treatment for ruptured IPDA aneurysms and dissections is endovascular embolization.11 Metallic coils are increasingly used to occlude the ruptured aneurysm or dissection. Regarding embolization, coils are placed at both the afferent and efferent arteries close to the bleeding site because of the presence of collateral arteries around the pancreas.12 In some cases, surgery may be an option due to the complexity of the pancreatic arcade and the difficulty of catheterization due to celiac artery stenosis. Surgical treatment is also indicated when embolization is unsuccessful. Performing surgical ligament release in CACS patients with ruptured aneurysms is not yet established.3,13Abdominal artery release surgery is expected to improve the symptoms of CACS and prevent subsequent aneurysms, but its long-term effects are unknown. In this case, after discussing the benefits and risks of surgery with the patient, we chose to observe the patient without performing surgery.
In conclusion, we report the successful endovascular treatment of ruptured PIPDA dissection associated with CACS. Celiac artery stenosis can cause retroperitoneal hemorrhage secondary to visceral aneurysm and dissection. Clinicians may consider CACS as the cause of visceral aneurysm and dissection in patients with chronic abdominal symptoms.
Conflicts of Interest: The authors declare no conflicts of interest.
Acknowledgments: None.
Funding: None.
Author contributions : KN: drafted the manuscript. HA, TI, JK, and HK: critically revised the manuscript. All authors read and approved the final manuscript.
Ethical approval: Applicable.
Informed consent: Informed consent was obtained from the patient.