Bruce said: "Anyone who has known me over the years knows that I have never publicly criticised another footballer. In this case, though, I find it ridiculous that this club who have given him his chance in England - and pay him very well I might add - are not being treated properly.
"We are not being shown any respect, it is totally nonsensical. We believe he has a hamstring, but we do not know how bad because we have not been able to assess him. We have had some sort of fax or e-mail to our medical people about it, but how bad it is we will not know until he reports back. He is still in Egypt and may be back some time in the week but we do not know when.
"This is not the first time. It is the fifth time and it cannot go on. We must now find out what his mindset is and what he is up to. It is a ridiculous situation, I have never known anything like it.
"You would think he would have some respect for me and the club, but in particular his fellow players, and we could have done with him against Everton."
He added: "We have spoken to his agent a few days ago, but whether he is coming back and when I do not know. I wouldn't hold my breath.
"I want him back so I can have a conversation to see where he is at, because he made a huge contribution to the club. Where it has gone wrong I do not know, obviously he is finding it difficult to settle in the country.
"We will just have to wait until we have that conversation. I do not know the situation about whether we keep him. If it happens once you can forgive and forget, but people are looking at me in the dressing room and saying 'what am I going to do?'
"It is a very difficult situation. The reason why we are having a good season is because he got 10 goals early on and it is a huge disappointment. For the decade or so that I have been doing this job, I have never known anything like this. We will deal with it when he returns."