Noncardiogenic pulmonary edema as the chief manifestation of a pheochromocytoma: a case report of MEN 2A with pedigree analysis of the RET proto-oncogene

Contribution of α - and β -Adrenergic Mechanisms to the Development of Pulmonary Edema

Endogenous or exogenous catecholamines can induce pulmonary edema (PE). This may occur in human pathologic conditions such as in pheochromocytoma or in neurogenic pulmonary edema (NPE) but can also be provoked after experimental administration of adrenergic agonists. PE can result from stimulation with different types of adrenergic stimulation. With α-adrenergic treatment, it develops more rapidly, is more severe with abundant protein-rich fluid in the alveolar space, and is accompanied by strong generalized inflammation in the lung. Similar detrimental effects of α-adrenergic stimulation have repeatedly been described and are considered to play a pivotal role in NPE or in PE in patients with pheochromocytoma. Although β-adrenergic agonists have often been reported to prevent or attenuate PE by enhancing alveolar fluid clearance, PE may also be induced by β-adrenergic treatment as can be observed in tocolysis. In experimental models, infusion of β-adrenergic agonists induces less severe PE than α-adrenergic stimulation. The present paper addresses the current understanding of the possible contribution of α- and β-adrenergic pathways to the development of PE.

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.

[Intra-alveolar hemorrhage revealing pheochromocytoma]

We report a case of pheochromocytoma revealed by alveolar hemorrhage in a 51-year-old woman. Pheochromocytomas are rare tumors deriving from the chromaffin tissue, and which clinical manifestations are highly variable, mostly unspecific, and very rarely concern the lung. Therefore, the diagnosis is often missed or delayed. However, without correct diagnosis and subsequently adapted treatment, the disease may be fatal. Thus, clinicians should be aware of the possible diagnosis of pheochromocytoma in patients presenting hemoptysis of an unknown origin.

Increased neutrophils in bronchoalveolar lavage fluids from a patient with pulmonary edema associated with pheochromocytoma

Pulmonary edema, both cardiogenic and noncardiogenic, has been reported as a manifestation of pheochromocytoma. We report a patient with pheochromocytoma complicated by acute pulmonary edema that appeared clinically noncardiogenic. The patient had an uncomplicated course and rapid resolution of pulmonary edema. Bronchoalveolar lavage fluids (BALF) showed a marked accumulation of neutrophils, suggesting involvement of neutrophil-mediated lung injury in noncardiogenic pulmonary edema associated with a pheochromocytoma.