[What is confirmed in therapy of complicated urinary tract infections].

Urinary tract infections (UTI) rank among the most common bacterial infections worldwide. Clinical challenges include acute severe manifestations and frequently relapsing disease, both favored by urinary tract abnormalities and systemic immune defects. To judge morbidity during clinical infection, the ORENUC criteria assess clinical risk, likelihood of relapsing disease, extragenital manifestations, nephropathy, urologic and catheter-related factors. Additional diagnostic measures of severe and unusual manifestations include an extended history and specific clinical examination together with nephro-urological imaging, namely ultrasound, laboratory assessment of systemic disease, and removal or exchange of catheters and other foreign materials in the urinary tract. The current primary antibiotics recommended for uncomplicated pyelonephritis in Germany are gyrase inhibitors and cephalosporins. Microbiological diagnosis and resistance testing is central to improve efficacy and reduce side effects, especially in complex clinical situations. New antibiotic developments offer new options, especially in presence of proven antimicrobial resistance. Management of relapsing infections needs to aim at improvement of local urogenital and systemic immunological factors, which is however frequently challenging to impossible to achieve. Patient contributions including behavioral modifications and longterm or intermittent antibiotic and other drug therapy. Overall, therapeutic options are limited and new pathophysiological and antimicrobial strategies are urgently needed.