Urinary tract infection (UTI) Urinary tract infection symptoms include pain during urination, an intense urge to urinate, and more. Kidney infection (pyelonephritis) Kidney infection, caused by bacteria, is marked by sudden chills and fever, pain, nausea and urinary issues Urine cultures are positive in 90 percent of patients with acute pyelonephritis, and cultures should be obtained before antibiotic therapy is initiated. ... Indications for inpatient treatment include complicated infections, sepsis, persistent vomiting, failed outpatient treatment, or extremes of age for confimation perform urine analysis Although patients with acute pyelonephritis traditionally have been hospitalized and treated with intravenous antibiotics, outpatient oral therapy is successful in 90 percent of selected patients with uncomplicated acute pyelonephritis who can tolerate oral intake, will be compliant with the treatment regimen, will return for early follow-up, and have adequate social support. Patients with complicated acute pyelonephritis who are more ill or have not responded to outpatient therapy should be hospitalized. Using specific hospitalization criteria .up to 70 percent of patients can be selected for outpatient management. Another option is initial therapy with parenteral antibiotics in an inpatient observation unit, followed by oral therapy as an outpatient.