Severe hypophosphataemia mimicking Guillain-Barré syndrome.

A 42 year-old woman presented with neurological symptoms suggestive of Guillain-Barré syndrome and required ventilatory support. She was found to have severe hypophosphataemia that was corrected promptly after which her trachea was extubated. She then revealed that she had undergone a prolonged religious fast and had just started eating again when her symptoms started. Over the next 2 weeks she made a complete recovery.