Urine cloudiness (murky or turbid urine) refers to a loss of the normal clear, straw-yellow appearance of urine. It results from suspended particles such as leukocytes, erythrocytes, epithelial cells, bacteria, mucus, crystals, or fat. Cloudiness is most often associated with urinary tract infection (UTI) but may also reflect specimen contamination, crystalluria, or other systemic or renal disorders.

Pathophysiology

• Infective/inflammatory processes→ Pyuria, bacteriuria, or mucus increases urine turbidity by scattering light.

• Crystalluria or alkaline urine→ Precipitation of phosphates or urates in alkaline urine may appear as milky sediment.

• Hematuria or lipiduria→ RBCs, chylomicrons, or nephrotic-range proteinuria can produce opaque or whitish urine.

• Storage artifact→ Prolonged standing at room temperature allows precipitation of salts or bacterial growth, falsely suggesting infection.

History and Physical Examination

History

• Onset and duration of cloudiness

• Associated urinary symptoms: dysuria, frequency, urgency, hematuria, suprapubic/flank/back pain

• Systemic features: fever, chills, nausea, malaise

• Past history: recurrent UTIs, renal stones, diabetes, immunosuppression

• Catheterization or recent urologic surgery/procedures

• Fluid intake and dietary factors (e.g., high phosphate foods)

Physical Examination

• Inspect urine for color, odor, debris, or sediment

• Palpate suprapubic area for tenderness or bladder distention

• Percuss/palpate flanks for costovertebral angle tenderness

• Assess for fever or signs of sepsis in catheterized or high-risk patients

Medical causes of urine cloudiness

Other causes

• Post-instrumentation hematuria or debris

• Vaginal or prostatic secretions contaminating specimen

• Rare: chyluria, severe proteinuria, or fungal infection

Emergency interventions

• Cloudy urine with sepsis or obstruction → Obtain urgent cultures, start empiric broad-spectrum antibiotics, and ensure unobstructed urine drainage.

• Catheter-associated cloudy urine with fever → Remove or replace catheter promptly before starting therapy.

Special considerations

• Always obtain a fresh, clean-catch sample before initiating antibiotics.

• In catheterized patients, collect urine from the sampling port after disinfecting it, not from the drainage bag.

• Encourage hydration to flush debris and reduce urine concentration.

Patient counseling

• Emphasize completing the full course of prescribed antibiotics.

• Advise increased water intake unless contraindicated.

• Teach proper genital and perineal hygiene (front-to-back wiping in women, cleaning before midstream collection).

• Avoid prolonged storage of specimens before laboratory testing.

Pediatric pointers

• Cloudy urine in infants or children often signals UTI; symptoms may be nonspecific (fever, irritability, vomiting).

• Consider congenital anomalies or dysfunctional voiding if infections are recurrent.

Geriatric pointers

• In older adults, cloudy urine may be the earliest sign of UTI or asymptomatic bacteriuria.

• Evaluate for delirium, dehydration, or medication effects (e.g., phosphate-containing laxatives).

References

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