The study aims to investigate bacteriological efficacy of a nitrofurantoin formulation given twice daily for seven days in the treatment of adult patients with microbiologically confirmed uncomplicated urinary tract infection.

Additional study objectives are to evaluate clinical efficacy as well as safety and tolerability of the nitrofurantoin formulation.

Inclusion Criteria:

• non-pregnant women and men aged above 18 years old
• presence of ≥ 2 signs or symptoms suggestive of a UTI (dysuria, urinary frequency, urgency, suprapubic pain) with onset 10 days before enrollment
• asymptomatic patients with available positive urine culture
• pyuria defined as positive leucocyte esterase (LE) test with any color change after two minutes
• collection of clean-voided midstream urine sample for culture and susceptibility testing to confirm bacteriuria
• normal renal function (defined as blood creatinine < 1.4 mg/100 ml)
• able to take oral medication on an outpatient basis
• written informed consent before enrollment

Exclusion Criteria:

• suspicion of complicated UTI (presence of fever above 38°C, flank pain, known urologic structural abnormality) or prostatitis
• negative urine dipslide results (uropathogen < 100000 CFU (colony-forming units)/mL) or presence of nitrofurantoin resistant isolate uropathogens or mixed cultures of more than two isolates
• symptoms of UTI within the past 4 weeks
• evidence of predisposing factor to UTI (e.g. calculi, stricture, primary renal disease like polycystic renal diseases and neurogenic bladder)
• medical history of anaemia, complicated diabetes mellitus, peripheral neuropathy, vitamin B deficiency, renal insufficiency, other significant renal, hepatic or lung diseases
• medical history of glucose-6-phosphate dehydrogenase deficiency (G6PD)
• electrolytes disorders
• pregnant, breast-feeding women or not using medically accepted, effective method of birth control
• history of nitrofurantoin hypersensitivity
• use of systemic bacteriological agent within 48 hours before enrollment