My father is 88 had a bad infection after a eurolift procedure over a month ago. He has struggled to regain his strength since. He is weak, somewhat wobbly on his feet, aches and pains in extremities. We took him to the ER on Friday because he wanted to know for sure the infection was not back. His white count was normal, red count to, vitamin B12 normal, hrs to grow) . So what is causing this?