Treatment ofchronic urinary tract infections

SYNOPSISGentamicin was ofvalue inthetreatment ofchronic urinary tractinfections caused by multiresistant bacterial strains forwhichno atoxic antibiotic was available. Thetreatment was carried outafter alkalinization ofthepatient's urine. Withthedosage given, gentamicin gave alow serumandarelatively highurine concentration. Excretion ofactive gentamicin intheurine was high even inpatients withimpaired renal function. Theresults oftreatment ofcomplicated chronic urinary tractinfections withinitial gentamicin andfollowing long-term therapy showednegative urinary cultures in12outof24patients within one to14monthsoffollow-up time. Toreduce the risk oftoxic sideeffects thedosage was adjusted according tothepatient's kidney function. No development ofresistance was demonstrated inthebacteria. Chronic urinary tract infections caused byvarious Gram-negative bacteria posean ever-increasing problem fromthepoint ofviewoftreatment. These bacteria areoften naturally resistant tomanyantibiotics orhavedeveloped resistance against sulphonamides, penicillins, streptomycin, tetracyclines, chloramphenicol, andnitrofurantoin. Theantibiotics whichremainfortreatment are,forexample, kanamycin, neomycin, polymyxin B,andcolistin. However, these antibiotics arepotentially neuro-, oto-, ornephrotoxic, particularly whennotgiven in reduced doses topatients withanunderlying kidney disease. Thisreport describes ourexperience inthe treatment ofchronic urinary tract infections witha newantibiotic, gentamicin. Thedrughadnotbeen usedinSwedenbefore. Gentamicin isamixture ofantibiotics whichare