What are the indications for doing FISH?
FISH analysis of colonic biopsies is a vital adjunct to the diagnosis of Boxer dog colitis, in order to assess colon biopsies for evidence of intramucosal and intracellular bacterial invasion. If bacterial invasion is present, the invading species is usually E. coli, and we use a specific probe to detect E. coli infection. Diagnosis of bacterial invasion helps to formulate a treatment plan, in conjunction with colon culture and antimicrobial susceptibility data. It is important to appreciate that colon culture alone by no means confirms E. coli invasion, and for maximal diagnostic yield, culture data must crucially be interpreted alongside FISH for spatial localization of bacteria. FISH can also be very helpful in clinical cases where where bacterial involvement is suspected based on clinical or histological evidence, for example in chronic granulomatous diseases, cholangiohepatitis, endocarditis, suppurative pancreatitis, pyelonephritis, lymphadenitis, chronic cystitis.
