A case of ischemic colitis associated with pheochromocytoma

Postoperative Management in Patients with Pheochromocytoma and Paraganglioma

Pheochromocytomas and paragangliomas (PPGLs) are rare catecholamine-secreting neuroendocrine tumors of the adrenal medulla and sympathetic/parasympathetic ganglion cells, respectively. Excessive release of catecholamines leads to episodic symptoms and signs of PPGL, which include hypertension, headache, palpitations, and diaphoresis. Intraoperatively, large amounts of catecholamines are released into the bloodstream through handling and manipulation of the tumor(s). In contrast, there could also be an abrupt decline in catecholamine levels after tumor resection. Because of such binary manifestations of PPGL, patients may develop perplexing and substantially devastating cardiovascular complications during the perioperative period. These complications include hypertension, hypotension, arrhythmias, myocardial infarction, heart failure, and cerebrovascular accident. Other complications seen in the postoperative period include fever, hypoglycemia, cortisol deficiency, urinary retention, etc. In the interest of safe patient care, such emergencies require precise diagnosis and treatment. Surgeons, anesthesiologists, and intensivists must be aware of the clinical manifestations and complications associated with a sudden increase or decrease in catecholamine levels and should work closely together to be able to provide appropriate management to minimize morbidity and mortality associated with PPGLs.

Ischemic Colitis: An Uncommon Manifestation of Pheochromocytoma

Pheochromocytoma are rare neuroectodermal tumors, responsible for less than 1 per cent of cases of hypertension. The protean manifestations of pheochromocytomas arise from the effects of catecholamine hypersecretion upon α and β receptors. The lesion may infrequently present with gastrointestinal complaints ranging from constipation and nausea to megacolon and ischemic colitis. Ischemic colitis in association with pheochromocytoma occurs from intense splanchnic vasoconstriction. A case of pheochromocytoma presenting as ischemic colitis is reported.

Emergencies caused by pheochromocytoma, neuroblastoma, or ganglioneuroma

Pheochromocytoma may lead to important emergency situations, ranging from cardiovascular emergencies to acute abdomen and multiorgan failure. It is vital to think about this disease in any emergency situation when conventional therapy fails to achieve control or symptoms occur that do not fit the initial diagnosis. The importance of keeping this diagnosis in minds is underscored by the fact that, in 50% of pheochromocytoma patients, the diagnosis is initially overlooked. Two other tumors of the sympathetic nervous system, neuroblastoma and ganglioneuroma, are less commonly associated with emergency conditions. If they occur, they are often linked to catecholamine excess, paraneoplastic phenomena, or local tumor mass effect.

Bowel Perforation as a Presenting Feature of Pheochromocytoma: Case Report and Literature Review

OBJECTIVE

To report a case of colonic perforation as the initial manifestation of pheochromocytoma and discuss the underlying pathophysiologic mechanism.

METHODS

The clinical, biochemical, radiologic, and pathologic findings are described. In addition, the management of the patient is discussed and the relevant literature reviewed.

RESULTS

A 57-year-old man presented with large bowel perforation after pseudo-obstruction. Emergency laparotomy revealed two cecal perforations but no obstructing lesion; however, hypertension persisting postoperatively raised the suspicion of pheochromocytoma. This diagnosis was confirmed by measurement of 24-hour urinary hydroxymethylmandelic acid excretion and computed tomography of the abdomen. The tumor was subsequently resected without complication or recurrence of bowel symptoms. The pathophysiology of bowel perforation in patients with pheochromocytoma is not entirely clear but most likely involves bowel ischemia and necrosis as a result of mesenteric vasoconstriction. This setting coupled with increased intraluminal pressure as a consequence of pseudo-obstruction may cause perforation.

CONCLUSION

Bowel perforation in patients with pheochromocytoma is rare and thought to be a consequence of intestinal ischemia and altered motility. This is potentially a life-threatening complication, particularly if the tumor remains undiagnosed and an emergency surgical procedure is necessary. Pharmacologic treatment of pheochromocytoma during pseudo-obstruction may prevent subsequent perforation. Clinicians should be aware of the potential gastrointestinal presentation of this tumor.

CT of acute bowel ischemia

Bowel ischemia may be caused by many conditions and manifest with typical or atypical and specific or nonspecific clinical, laboratory, and radiologic findings. It may mimic various intestinal diseases and be confused with certain nonischemic conditions clinically and at computed tomography (CT). Bowel ischemia severity ranges from mild (generally transient superficial changes of intestinal mucosa) to more dangerous and potentially life-threatening transmural bowel wall necrosis. Causes of critically reduced blood flow to the bowel are diverse, ranging from occlusions of mesenteric arteries or veins to complicated bowel obstruction and overdistention. CT can demonstrate changes in ischemic bowel segments accurately, is often helpful in determining the primary cause of ischemia, and can demonstrate important coexistent findings or complications. Unfortunately, common CT findings in bowel ischemia are not specific, and specific findings are rather uncommon. Therefore, it often is a combination of nonspecific clinical, laboratory, and radiologic findings-especially detailed knowledge about the pathogenesis of acute bowel ischemia in different conditions-that helps most in correct interpretation of CT findings. To improve understanding of this complex heterogeneous entity, this article provides an overview of the anatomy and physiology of mesenteric perfusion and discussions of causes and pathogenesis of acute bowel ischemia, CT findings in various types of acute bowel ischemia, and potential pitfalls of CT.

A painful pulsatile abdominal mass in a young man with elevated blood pressures: an unusual presentation of phaeochromocytoma

We report an unusual presentation of phaeochromocytoma in a young man with a painful, pulsatile abdominal mass and elevated blood pressures. This led to a delay in diagnosis and resulted in the administration of triggers of catecholamine release, possibly causing a catecholamine surge. This caused the development of catecholamine-induced cardiomyopathy and multiple organ failure, requiring inotropic and ventilatory support, intra-aortic balloon pump and dialysis. Fortunately, his condition reversed with supportive treatment and alpha-adrenergic blockade. This illustrates the importance of having a high index of suspicion of phaeochromocytoma, especially in young patients with elevated blood pressures.