Pathophysiologic Findings in a Patient with Shy-Drager and Alveolar Hypoventilation SyndromesRespiratory disturbances during wakefulness and sleep are common in patients with the Shy-Drager syndrome. The available pathologic studies describe lesions in the brainstem and conclude that these morphologic changes were responsible for the premorbid disturbances in respiratory control.- In this case, despite hypercapnic respiratory failure and apnea/hypoventilation during sleep, at autopsy there were no pontomedullary abnormalities.
Case Report
This hospitalized 73-year-old black man was evaluated nine months after he was admitted in respiratory failure. Two years prior to evaluation, he developed excessive daytime sleepiness, episodic shortness of breath, and confusion. Syncope and urinary frequency developed the next year. Nine months prior to evaluation, he was admitted for respiratory failure. A tracheostomy was performed because of obstructive apnea during sleep and hypercapnic respiratory failure. A transurethral resection of the prostate revealed an unsuspected adenocarcinoma of the prostate. The patient was unable to leave the hospital because of orthostatic hypotension.

On physical examination, the blood pressure was 150/80 mm Hg, and the heart rate was 72 beats per minute in the supine position. Values when standing were 90/60 mm Hg and 84 beats per minute. The patient did not perspire. There was a grade 2/6 systolic murmur at the upper right sternal border radiating to the apex, mild pretibial edema, and no movement of the right diaphragm. For the length of his hospital stay, the patient was oriented only to person. Typical parkinsonian features and tremor were present. His posture was flexed and he walked slowly with small shuffling steps. Reflexes were diminished at the ankles and knees. There was a mild decrease in perception of pin and vibration in both lower extremities. canada health and care mall
Tests of the autonomic nervous system confirmed sympathetic dysfunction. Hematocrit value was 31 percent. Serum electrolytes, chemistries and cerebrospinal fluid analysis results were normal. Parathyroid hormone was 945 mg/dl (nl 0-500). The VDRL test results were nonreactive. Nerve conduction studies demonstrated a mild distal polyneuropathy of the axonal type with an absent sural sensory response and slowing of conduction in peroneal, posterior tibial, and ulnar nerves. Concentric needle examination disclosed chronic neurogenic motor units, decreased interference pattern, and fibrillations in distal muscles.