Paraneoplastic Encephalomyelitis and Subacute Dysautonomia due to an Occult Atypical Carcinoid Tumour of the Lung

Abstract

A case of paraneoplastic encephalomyelitis and subacute pandysautonomia associated with an occult atypical carcinoid tumour of the lung is described. The main clinical features were lethargy, impaired memory, constipation, and orthostatic hypotension. Neurological investigation was unremarkable except for mononuclear pleocytosis and increased protein level in the cerebrospinal fluid (CSF). Tests of autonomic function revealed a low plasma norepinephrine level, a marked drop of blood pressure (BP) to vertical tilt and Valsalva maneuver, and a marked rise of BP to dilute norepinephrine infusion. A few days prior to death, the patient became hypothermic and had repeated episodes of respiratory arrest associated with transient atrioventricular block on the electrocardiogram (ECG). A polysomnography study confirmed a sleep apnea syndrome. Autopsy revealed an atypical carcinoid tumour in one tracheobronchial lymph node, widespread lymphocytic infiltrates and loss of neurones in the cerebral, cerebellar and brainstem gray matter, the spinal cord and roots, and the paravertebral sympathetic ganglia as well as microglial and astrocytic proliferation in the central nervous system. © 1990, Canadian Neurological Sciences Federation. All rights reserved.