Parkinsonism due to Fahr's disease with previous carbon monoxide intoxication.

Abstract

We report a 72 year male patient who presented with a progressive gait disturbance, starting hesitation and difficulties with turning around himself, which appeared in the last few years. In his neurological examination, we found short step gait in anteflexion with starting hesitation, mild masked face, micrography and mild upward gaze palsy. At the age of 34, the patient was hospitalized because of a comatose state due to carbon monoxide (CO) intoxication, and the initial critical care management included cardiopulmonary resuscitation. Since then he complained of difficulties with movement synchronization. He has been treated with lacidipine, atenolol and metformin because of arterial hypertension and diabetes mellitus. Brain computed tomography (CT) and magnetic resonance (MRI) showed necrotic lesions in both caudate nuclei with calcifications in both basal ganglia (Figs. 1, 2). Wilson’s disease, hypoparathyroidism, pseudohypoparathyroidism and hyperparathyroidism were excluded. His laboratory work-up showed elevated values of glucose (9.1 mmol/L), triglycerides (2.06 mmol/L), total cholesterol (5.04 mmol/L) and LDL cholesterol (3.5 mmol/L). Symptomatic treatments with L-dopa and dopamine agonist were not successful. Our case demonstrates the markedly delayed onset of progression of parkinsonism in the patient with previous carbon monoxide poisoning that did not respond to conventional therapy. Most likely, the patient has Fahr’s disease according to radiological and clinical findings. However, diagnostic criteria of Fahr’s disease are not completely fulfilled, because there is a previous history of toxic exposure and no positive family history [1]. Progressive supranuclear palsy-like phenotype is associated with striopallidodentate calcification [2]. Carbon monoxide intoxication is one of the most common fatal accidental poisoning [3]. Parkinsonism is present in 10 % of patients with previous carbon monoxide poisoning, and it is usually associated with a delayed CO encephalopathy [4]. The neuroradiological findings are variable but lesions of globus pallidus and white matter lesions are common findings on brain MRI in these patients [5]. Calcifications of basal ganglia have been reported after CO intoxication, but in most cases these calcifications are present in globus palidus and they are not extensive [6, 7]. In our case, extensive lesions in caudate nuclei are probably caused by Fahr’s disease, but small calcifications in globus pallidus are possibly caused by previous CO intoxication. However, the substantia nigra injury has the role in pathophysiology of CO-induced parkinsonism [8]. In conclusion, because of the impressive radiographic findings, the long interval between the CO-intoxication and the progression of drug-resistant parkinsonism, Fahr’s disease was identified as a primary cause. The clinical picture was further influenced by probable substantia nigra injury as a consequence of previous carbon monoxide intoxication. & Hrvoje Budincevic hbudincevic@gmail.com