Clinical Geriatrics

CASE PRESENTATION
A 67-year-old bedridden African-American female was brought to the emergency room (ER) by her husband with the acute onset of altered mental status changes and urinary incontinence. From her history it was revealed that 1 week prior to this episode she had been evaluated by the Neurology service as an outpatient for possibly having had syncopal episodes over the previous several months. An electroencephalogram (EEG) done during that visit showed cortical instability with intermittent slowing in both hemispheres, and transient sharp waves consistent with a cerebral infarction and/or an underlying structural abnormality. She had not yet been seen for follow-up of these results. The patient had also had an episode of dehydration 4 months prior, and during her work-up at that time a calcium level of 11.2 mg/dL had been found.

Investigation
The patient’s past medical history included hypertension and a cerebrovascular accident (CVA) 8 years previous, with residual left hemiparesis that left her unable to ambulate. Her medications included nifedipine, hydrochlorothiazide, aspirin, and isosorbide dinitrate. She was afebrile, and her vital signs were within normal limits, except for a blood pressure of 178/80 mm Hg. On physical examination, the patient was found to be somnolent but arousable to verbal and tactile stimuli. Her mucous membranes and oral mucosa were found to be dry, and skin turgor was reduced. The lung fields were clear and heart sounds regular without murmurs, gallops, or rubs. No carotid or abdominal bruits were auscultated. Both upper and lower extremities revealed 3+ hyperreflexia with a persistent right-sided facial droop and left-sided Babinski reflex.

Her laboratory tests revealed the following: sodium 130 mEq/L; potassium 3.2 mEq/L; chloride 86 mmol/L; blood urea nitrogen and creatinine, 11 and 1.3, respectively; calcium 12.7 mg/dL; magnesium 1.3 mEq/L; and phosphate 1.8 mg/100 mL. Hemoglobin was 11.4 g/100 mL and hematocrit 34%. A finger stick was 125 mg/100 mL, and O₂ saturation was 98%. A toxicology screen was negative, and urinalysis showed only trace protein.

A computed tomography (CT) scan of the head showed mild atrophy, periventricular white matter ischemic changes, and an old low-signal density around the right thalamus. A chest x-ray showed an atherosclerotic aorta and a retrocardiac opacity that could have representated atelectasis or pneumonia. An electrocardiogram (EKG) revealed normal sinus rhythm, a left anterior fasicular block, and an old septal infarct.

Subsequent laboratory tests showed a low albumin level of 2.9 g/dL, thyroid-stimulating hormone (TSH) of 1.3 μIU/mL, and a mildly elevated alkaline phosphatase of 143 units per liter (U/L).

In addition to intravenous fluids, the patient was started on IV heparin and a beta blocker until the cardiac enzymes came back with negative results. A neurology evaluation in the ER had recommended a malignancy work-up for metabolic encephalopathy, and phenytoin was initiated. The patient was admitted, and a 2-dimensional echocardiogram showed an ejection fraction of 65%, mild-to-moderate mitral and tricuspid regurgitation, and an area of distal anteroseptal and apical hypokinesis.

Diagnosis
Given her elevated serum calcium and alkaline phosphatase levels, a bone scan was done, which revealed intense uptake throughout the skull with accentuation of the skull contour. There was also milder increased uptake involving the T11 and L2 vertebrae. These findings were typical and consistent with a diagnosis of Paget’s disease of bone.

GENERAL ASPECTS OF PAGET’S DISEASE
Paget’s disease (also known as osteitis deformans) is a chronic skeletal disorder that is commonly seen in the elderly, and is the second most common bone disease in the United States after osteoporosis.