Statistics from Altmetric.com
Answers on p 673.
A 61 year old woman presented with a one week history of headache, drowsiness, and shortness of breath. Initial examination revealed bilateral ptosis, which the patient stated had been present for three to four years before this admission. She also reported that her father had died suddenly, shortly after developing “drooping eyelids”. There was restriction in the range of eye movements in all directions. The remaining cranial nerves were intact.
In the limbs there was normal tone but mildly reduced power in all muscle groups, worse proximally. There was generalised areflexia. Plantar responses were flexor and there was no sensory deficit. Coordination was normal. There were no signs of meningism. On chest examination there was reduced air entry bilaterally and bronchial breathing in both lower zones. Cardiovascular and abdominal examinations were unremarkable.
There was a past medical history of pernicious anaemia, osteoporosis, partial thyroidectomy, and cholecystectomy. Drugs on admission were disodium etidronate and hormone replacement therapy.
Laboratory investigations included an arterial pH of 7.34, oxygen pressure 11.78 kPa, carbon dioxide pressure 7.1 kPa, and a base excess +5.1. Urea and electrolytes, creatinine, calcium, creatinine kinase, and lactate were all within normal limits. Full blood picture was unremarkable and cerebrospinal fluid examination was also normal. A chest radiography showed bilateral lower lobe collapse and consolidation. The electrocardiogram is shown in fig 1.
The patient's condition deteriorated with increasing respiratory distress. Her respiratory rate rose to 32 breaths/min, repeat arterial blood gases indicated pH 7.30 kPa, oxygen pressure 9.9 kPa, and carbon dioxide pressure 8.9 kPa. The patient was transferred to intensive care for ventilatory support.
- What is the differential diagnosis for this clinical presentation?
- What does the electrocardiogram (fig 1) show and what is the significance of this?
- What other clinical findings would be useful to elicit?
- What further investigations would you like to perform?