Mohamed Fahmy, 39, of the Qatar-based Al Jazeera English channel, was arrested in December and is on trial with two colleagues and 17 other defendants on charges that include providing a platform to the outlawed Muslim Brotherhood group.
Fahmy was suffering from a fractured arm before his arrest. Adel Fahmy said his brother's condition has deteriorated since due to negligence and harsh prison conditions.
In a letter received by the family today, interim President Adly Mansour reassured the family their son would get a fair trial, and said he instructed authorities to ensure Fahmy gets the best treatment possible.