Answer to Case 55
What is the most likely diagnosis now?
The history suggests a subacute onset of back pain, difficulty mobilising, leg weakness and sphincter disturbance. The signs on examination are suggestive of an upper motor neuron lesion with increased tone, a pyramidal pattern of weakness and hyperreflexia with clonus; this is the clinical picture of a spastic paraparesis (Box 2.1 ). The absence of any findings in the arms or cranial nerves, together with the presence of a sensory level, strongly suggest spinal cord pathology. In a patient of this age group, the most likely diagnosis would be malignant cord compression (particularly in the presence of systemic features of malignancy). Spondylitic disease is also a possibility. In any case, urgent neuroimaging is required to investigate this further.
Arthur is rushed to the radiology department for urgent imaging of his spinal cord (Fig. 2.2). This confirms the neurologist’s suspicion of malignant cord compression and he is treated immediately with high-dose intravenous steroids. A chest X-ray shows a suspicious lesion and following bronchoscopy he is diagnosed with small cell carcinoma of the lung. He receives radiotherapy to the spinal cord metastasis and is commenced on chemotherapy to treat the underlying cancer. At his 3-month review he is still ambulating and is free from back pain.