What is the next step in managing a male patient with leukocyte esterase and ketones in his urine, a history of cannabis use, and hyperlipidemia (HLD), but no urinary symptoms and a negative sexually transmitted infection (STI) panel?

Management of Asymptomatic Leukocyte Esterase and Ketonuria in a Male Patient

Do not pursue further urinary tract infection workup or treatment in this patient, as the presence of leukocyte esterase without urinary symptoms does not indicate infection and requires no intervention. 1

Clinical Interpretation

Leukocyte esterase positivity without symptoms represents asymptomatic pyuria, which has exceedingly low positive predictive value for actual UTI and should not be treated. 1 The combination of:

• Positive leukocyte esterase
• Absence of urinary symptoms (no dysuria, frequency, urgency, fever, or gross hematuria)
• Negative STI panel

...definitively indicates this is not a urinary tract infection requiring treatment. 1

Why No Treatment is Indicated

• Pyuria alone is insufficient for UTI diagnosis - The Infectious Diseases Society of America explicitly states that leukocytes without accompanying urinary symptoms do not justify antimicrobial treatment (Grade A-II recommendation). 1

• Asymptomatic bacteriuria with pyuria is common - This occurs in 15-50% of certain populations and provides no clinical benefit when treated, only increasing antimicrobial resistance and exposing patients to unnecessary drug toxicity. 1

• The absence of symptoms excludes UTI - Treatment requires BOTH pyuria (≥10 WBCs/high-power field or positive leukocyte esterase) AND acute onset of specific urinary symptoms (dysuria, frequency, urgency, fever, or gross hematuria). 1

Addressing the Ketones

• Ketonuria in the context of cannabis use - Ketones in urine may reflect metabolic states including fasting, low carbohydrate intake, or cannabis-associated hyperemesis syndrome if present, but are unrelated to the leukocyte esterase finding. 2

• No urologic significance - Ketones do not affect the interpretation of leukocyte esterase test accuracy and do not indicate urinary tract pathology. 1

What NOT to Do

• Do not order urine culture - Culture is not indicated in asymptomatic patients regardless of urinalysis findings. 1

• Do not prescribe antibiotics - Treating asymptomatic pyuria provides no clinical benefit and causes harm through antimicrobial resistance development and adverse drug effects. 1

• Do not repeat urinalysis - Repeated testing in asymptomatic patients leads to overdiagnosis and overtreatment. 1

Appropriate Management Algorithm

If the patient remains asymptomatic:

• Provide reassurance that no infection is present. 1
• No further urologic workup is needed. 1
• No follow-up urinalysis is required. 1

Patient education - Return immediately if any of these develop:

• New-onset dysuria, urinary frequency, or urgency 1
• Fever >38.3°C 1
• Gross hematuria 1
• Suprapubic pain or costovertebral angle tenderness 1

Special Considerations for This Patient

• Cannabis use - The endocannabinoid system affects the urologic system, and cannabis use may influence lower urinary tract symptoms, but does not change the interpretation of asymptomatic leukocyte esterase. 2

• Hyperlipidemia - This comorbidity does not affect urinalysis interpretation or increase UTI risk. 1

• Male patient - In men, proper specimen collection (midstream clean-catch) minimizes contamination, but the absence of symptoms still precludes UTI diagnosis regardless of leukocyte esterase results. 1

Critical Pitfall to Avoid

The most common error is treating asymptomatic pyuria as if it were a UTI. This leads to unnecessary antibiotic exposure, increased antimicrobial resistance, potential adverse drug effects, and increased healthcare costs without any clinical benefit to the patient. 1 The Infectious Diseases Society of America provides strong evidence (Grade A-II) that screening for and treating asymptomatic bacteriuria with pyuria is not recommended. 1