My mom has been diagnosed with MRSA pneumonia and cavitory lung lesions what prognosis can we expect?

She is currently being treated with IV vancomycin (we're just beginning week 2) in hospital. The lesions in her lungs have grown four times in one week (via CT scan). She is in pain and is growing weary of being sick. They have checked a needle-guided biopsy of the lesions and the only thing growing is the MRSA. Please help us with some answers, even her DRs seem stumped.