Bilateral basal ganglia lesions in end-stage kidney disease presenting as acute chorea

Background

Acute movement disorder associated with bilateral basal ganglia (AMD- BBG) lesions is a syndrome that affects patients with diabetic uremia and, for reasons yet unclear, has been reported mostly in patients from Asia [1–3]. We report the case of a diabetic female with end-stage kidney disease (ESKD) who developed chorea with bilateral basal ganglia lesions. The unique radiological findings associated with this condition are described.

Case report

A 58-year-old Hispanic female with ESKD on maintenance hemodialysis presented to the emergency room with complaints of slurred speech of a few hours duration. Her medical history included type 2 diabetes, hypertension, peripheral vascular disease, hypothyroidism, sarcoidosis and ESKD secondary to diabetes on hemodialysis for 4 years. At the time of presentation, she was on clonidine, metoprolol, amlodipine, levothyroxine, aspirin, sevelamer and multivitamins. Family and social history were non-contributory. On examination, she was afebrile with a pulse rate of 68/min and a blood pressure of 180/90 mm Hg. Neurological examination failed to reveal any focal or localized findings besides motor dysarthria. The remainder of the examination was unremarkable. She underwent a computed tomography scan of her brain that showed bilateral lucencies in the basal ganglia with no evidence of small vessel ischemic changes or hemorrhage (Figure 1). The findings were new compared with a previous CT scan of her head done 21 months prior. Her biochemical and hematological test results at presentation were as follows: sodium 137 mEq/L (137 mmol/L), blood urea nitrogen (BUN) 45 mg/dL (16 mmol/L), creatinine (Cr) 6.9 mg/dL (610 µmol/L), bicarbonate 31 mEq/L (31 mmol/L), glucose 182 mg/dL (10.1 mmol/L), calcium 9.5 mg/dL (2.37 mmol/L), ionized calcium 5.18 mg/dL (1.45 mmol/L), white blood cell 5.8 × 10³/μL (5.8 × 10⁹ /L) and hemoglobin 10.3 gm/dL (103 g/L). She was started on hydralazine for elevated blood pressures with good response. During the course of her hospital stay, she continued to have slurring in her speech, and a repeat CT scan of her brain after 48 h showed no interval changes from the scan at admission. Carotid Doppler studies identified 40% stenosis at the common carotid bifurcation bilaterally. An echocardiogram revealed normal left ventricular function, chamber dimensions and thickness of the myocardium and normal valves. On the seventh hospital day, she manifested choreiform movements involving her upper extremities. In addition, she also had gait instability. A magnetic resonance imaging of her brain was performed that noted bilateral basal ganglia lesions with increased T2 signal intensity (Figure 2). Low signal intensity was noted on T1-weighted images and diffusion-weighted axial images. The biochemical profile on the day these symptoms manifested were as follows: sodium 135 mEq/L (135 mmol/L), potassium 4.2 mEq/L (4.2 mmol/L), bicarbonate 22 mEq/L (22 mmol/L), BUN 63 mg/dL (22.5 mmol/L), Cr 9.2 mg/dL (813 µmol/L), glucose 207 mg/dL (11.5 mmol/L) and calcium 9.1 mg/dL (2.3 mmol/L). Further evaluation yielded the following results: serum phosphorus 6.1 mg/dL (2.0 mmol/L); uric acid 6.2 mg/dL (368.8 µmol/L); iron 122 mg/dL; ferritin 561 ng/mL (561 µg/L) ; parathyroid hormone (bio intact) 133.3 pg/mL (133.3 ng/L); ESR 48 mm/h; aluminum <5 mcg/mL (normal 0–10 mcg/mL); ceruloplasmin 31 mg/dL (normal 20–60 mg/dL). Her urea reduction rate measured 74.51% and K_t/V was 1.78, indicating adequate hemodialysis. No episodes of hypotension were noted upon review of her dialysis records dating to 2 weeks prior to her hospitalization. She was diagnosed to have acute movement disorder (chorea) with bilateral basal ganglia lesions in ESKD. With conservative management over the next 5 days, she was gradually able to walk. The choreiform movements and slurring of her speech improved, but did not disappear completely at discharge 12 days from the admission.

Fig. 1.

CT scan of the brain without intravenous contrast. Bilateral lucencies in the basal ganglia with no evidence of hemorrhage or small vessel disease.

Fig. 2.

MRI of the brain. Bilateral basal ganglia lesions with increased T2 signal intensity.

Discussion

AMD-BBG has been reported only in diabetics with ESKD, and its unique radiological findings include bilateral basal ganglia lesions that appear hypodense on CT scan images. These lesions have a low signal intensity on T1-weighted images on MRI and a high signal intensity on T2-weighted images. The etiology and pathogenesis of AMD-BBG in ESKD patients have been debated and remain inconclusive [1, 2]. In the largest series of patients reported to date, 11 of 12 patients manifested with acute onset Parkinsonian symptoms (bradykinesia, rigidity, postural instability and gait disturbance), along with dysarthria, disturbance of consciousness, dyskinesia or dysphagia [2]. The syndrome is usually self-limiting with spontaneous regression that is accompanied by clinical improvement [2, 4]. To date, there are only a few reports describing acute-onset chorea associated with the bilateral basal ganglia lesions [4–7].

Correction of uremia and metabolic acidosis along with supportive therapy has been the main focus of management [3]. At present, there are no recommendations for any specific treatment for this syndrome [3]. A review of published cases has reported complete or partial regression of these lesions, in 83% of cases when neuroimaging was repeated at a median of 2 months after initial scans [8].

Our case represents a 58-year-old Hispanic lady with diabetes, uncontrolled hypertension and ESKD who suffered from AMD-BBG that manifested as chorea. A comprehensive neurological workup failed to identify a specific cause of basal ganglia injury. The etiology of these lesions remains unknown and whether genetic, environmental or dietary factors contribute remains to be clarified. We would like to highlight this rare case to raise awareness of this syndrome in the nephrology community.

Conflict of interest statement

None declared.