Diagnosis and drug treatment of acute pyelonephritis

The term pyelonephritis, which denotes infection of the renal pelvis and of the renal tissue, covers a spectrum of entities, the gravity and hence treatment of which depend upon the organism, its sensitivity to antibiotics, the presence or absence of urinary tract obstruction, and the host's background. The common form affects young females, is due to uropathogenic but multisensitive strains of Escherichia coli, and is easily treated by a 10- to 20-day course of antibiotic(s). In males, children and immunocompromised patients, renal and urinary tract imaging is necessary to determine the cause of the infection, the severity of the lesions and thus to guide the duration of treatment, which comprises antibiotic combinations for several weeks. Pyelonephritis during pregnancy may be serious, and treatment is restricted to certain antibiotics. Aminoglycosides, amino- or carboxypenicillins (alone or associated with clavulanic acid), ureidopenicillins (e.g. mezlocillin, piperacillin), fluoroquinolones (e.g. ciprofloxacin, ofloxacin, pefloxacin), cephalosporins, monobactams (e.g. aztreonam), carbapenems (e.g. imipenem) and the combination of trimethoprim plus a sulphonamide [e.g. cotrimoxazole (trimethoprim/sulfamethoxazole)] offer a wide choice of bactericidal agents which may be used for the treatment of pyelonephritis. However, the selection among them also depends on availability, antimicrobial spectrum, tolerance and cost.