From your past experience, a patient with normal kidney scans, with raised esr but no infections, with large amounts of protein & blood in urine-with normal blood results (apart from esr) what will her kidney biopsy reveal? likely cause that u think?

Any type of glomerular diseases (disease affects the glomerulus) will have those features (high ESR, blood and protein in the urine). There are blood tests (serology tests) which can give us a better hint for a more accurate diagnosis but kidney biopsy is the gold standard, not only for diagnosis but also for prognostic purpose. Fortunately, glomerular diseases can be treated most of the time.

what it will reveal is hard to predict. Yes it will try to find cause and help in diagnosis