With the aim to pilot a full-scaled trial to reduce unnecessary antibiotics in women with suspected uncomplicated urinary tract infections, twenty general practices in Bavaria, Germany, will be randomized to deliver patient management based on phase-contrast microscopy and urinary dipsticks or to usual care. Primary endpoints are recruitment and retention rates.

Introduction: Uncomplicated urinary tract infections (UTIs) in women are among the most common infections encountered in primary care after those of the respiratory tract. They are often self-limiting, even though antibiotics are prescribed for almost all women presenting with suggestive clinical features. Efforts directed to tackle antimicrobial resistance led to primary care randomized controlled trials (RCTs) that investigated alternative treatment strategies in these patients. While reducing antibiotic use substantially, none of the experimental treatments showed non-inferiority to antibiotics with respect to clinical outcomes such as symptom duration, symptom burden, and pyelonephritis. Evidence suggests that rapid point-of-care (POC) tests to detect bacteria and erythrocytes in urine at presentation may help primary care clinicians to select women with uncomplicated UTIs (unUTIs) in whom antibiotics can be withheld without affecting clinical outcomes. The aim of this study is to pilot a full-scaled primary care RCT to evaluate the effects of a POC diagnosis and treatment algorithm based on a combination of phase-contrast microscopy and urinary dipsticks on antibiotic use in women with symptoms of an unUTI.

Methods and analysis: MicUTI (Microscopy in UTI) is a pragmatic open-label two -arm parallel pilot cluster-RCT. Twenty general practices affiliated to the Bavarian Practice Based Research Network (BayFoNet) in Germany will be randomly assigned to deliver patient management based on POC-tests (POCTs) or to the usual care arm. Urine samples will be obtained at presentation for POCTs and microbiological analysis. All patients will be followed-up using a self-directed patient diary completed until day 7 from inclusion or until symptom resolution (up to day 14), and through telephone-calls at day 28. An electronic medical record review is performed in case of missing follow-up information.

Primary endpoints are patient enrollment and retention rates. Exploratory endpoints include antibiotic use for UTI at day 28, time to symptom resolution, symptom burden, the number of recurrent and upper UTIs and re-consultations, and diagnostic accuracy (POCTs vs. urine culture as reference standard).

Ethics, data protection and trial registration: The trial will be conducted in accordance to the declaration of Helsinki and the relevant data protection regulations. Institutional review board approval: 109/22-sc (December 16, 2022)

Inclusion Criteria:

• Women with at least two of dysuria, frequency, urgency, lower abdominal pain or hematuria.

Exclusion Criteria:

• Signs of a complicated UTI (anamnesis of fever, chills or flank pain)
• Clinically relevant immunosuppression (i.e., current use of any immunosup-pressive therapy, congenital or acquired disorders of immunity)
• Acute or chronic functional or anatomical variations in urinary tract except renal insufficiency grade II/IIIa
• Permanent bladder catheter or use of bladder catheter within the past two weeks
• UTI within the past two weeks
• Use of any antibiotic within the past two weeks
• Accommodation in a nursing home or hospital stay within the past two weeks
• Severe neurologic or psychiatric illness, severe dementia or severe substance use disorder
• Other severe diseases
• Being unable to understand the informed consent or to complete the patient diary
• Known pregnancy