Interleukin-6 Producing Pheochromocytoma: A Rare Cause of Systemic Inflammatory Response Syndrome

IL-6-Producing Pheochromocytoma Associated With Von Hippel Lindau Disease: A Case Report With Literature Review

We present a first case report of an IL-6-producing pheochromocytoma associated with von Hippel Lindau (vHL) disease. Pheochromocytomas are rare tumors that produce catecholamines, leading to various symptoms. In this case, a 28-year-old woman with a family history of vHL disease presented with a prolonged fever. Laboratory examinations revealed elevated C-reactive protein levels, and notably, a significantly increased serum IL-6 level. Imaging studies confirmed bilateral adrenal tumors with increased uptake on fluorodeoxyglucose-positron emission tomography and 123I-metaiodobenzylguanidine scintigraphy in the right adrenal gland. Despite partial relief with nonsteroidal anti-inflammatory drugs and alpha-blockers, her fever persisted until prednisolone administration, which promoted a complete resolution. A histopathological analysis following a right laparoscopic adrenalectomy revealed a typical pheochromocytoma. We conducted further analyses, including an enzyme-linked immunosorbent assay (ELISA), a quantitative real-time polymerase chain reaction (PCR) test, and immunoblot assays from the resected tumor tissues. We compared the current case with other cases of pheochromocytoma that presented neither elevated serum IL-6 nor high fever. Using ELISA, we found that this patient exhibited more IL-6 secretion than that seen in other cases. Additionally, quantitative real-time PCR and immunoblot found that both the phosphorylated signal transducer and activator of transcription 3 (STAT3) messenger RNA (mRNA) and protein expression levels exceeded those of the other cases. Thus, we surmised that IL-6 was produced directly from the tumor tissue and IL-6 expression was potentiated through the IL-6/STAT3 signaling pathway. Our findings contribute to the understanding of IL-6-producing pheochromocytomas and their distinct clinical characteristics.

Interleukin-6-producing paraganglioma as a rare cause of systemic inflammatory response syndrome: a case report

Pheochromocytomas and paragangliomas (PPGLs) may secrete hormones or bioactive neuropeptides such as interleukin-6 (IL-6), which can mask the clinical manifestations of catecholamine hypersecretion. We report the case of a patient with delayed diagnosis of paraganglioma due to the development of IL-6-mediated systemic inflammatory response syndrome (SIRS). A 58-year-old woman presented with dyspnea and flank pain accompanied by SIRS and acute cardiac, kidney, and liver injuries. A left paravertebral mass was incidentally observed on abdominal computed tomography (CT). Biochemical tests revealed increased 24-hour urinary metanephrine (2.12 mg/day), plasma norepinephrine (1,588 pg/mL), plasma normetanephrine (2.27 nmol/L), and IL-6 (16.5 pg/mL) levels. 18F-fluorodeoxyglucose (FDG) positron emission tomography/CT showed increased uptake of FDG in the left paravertebral mass without metastases. The patient was finally diagnosed with functional paraganglioma crisis. The precipitating factor was unclear, but phendimetrazine tartrate, a norepinephrine-dopamine release drug that the patient regularly took, might have stimulated the paraganglioma. The patient's body temperature and blood pressure were well controlled after alpha-blocker administration, and the retroperitoneal mass was surgically resected successfully. After surgery, the patient's inflammatory, cardiac, renal, and hepatic biomarkers and catecholamine levels improved. In conclusion, our report emphasizes the importance of IL-6-producing PPGLs in the differential diagnosis of SIRS.

Pheochromocytoma presenting as fever of unknown origin, a case report

Introduction: Pheochromocytoma is a generally benign neoplasm derived from chromaffin cells of the adrenal medulla. It is characterized by the production of large amounts of catecholamines and also by the capacity to secrete bioactive peptides such as cytokines, mainly interleukin-1 (IL-1), interleukin-6 (IL-6) and TNF alpha.Case presentation: 24-year-old man, who consulted for fever, myalgia, and choluria. His laboratory tests were compatible with a systemic inflammatory response without infectious or autoimmune causes. However, a fluorodeoxyglucose positron emission tomography (FDGPET) revealed a left adrenal mass, without extra-adrenal lesions. On admission, increased levels of differentiated urine methanephrines, elevated baseline cortisol, non-suppressed adrenocorticotrophic hormone (ACTH), and positive low dose dexamethasone suppression test for cortisol were found. With suspicion of catecholamine and ACTH-producing pheochromocytoma, a tumor resection was performed, which conspicuously resolved all alterations of the inflammatory response. The histologic findings confirmed a pheochromocytoma, but the immunostaining for ACTH was negative. A literature review and the comparison of the findings with other reported cases allowed inferring that this was a case of interleukin-producing pheochromocytoma.Conclusion: Pheochromocytoma may be a cause of febrile syndrome, with IL-6 being the main mediator, which explains the manifestationsof systemic inflammation and ACTH-mediated hypercortisolism.