Management of Elevated Leukocyte Esterase on Urine Test

Diagnostic Significance

The presence of leukocyte esterase in urine indicates inflammation in the urinary tract, suggesting a urinary tract infection (UTI), with moderate sensitivity (83%) and limited specificity (78%) 1
The combination of leukocyte esterase and nitrite testing improves diagnostic accuracy, with a combined sensitivity of 93% and specificity of 96% 1
The absence of pyuria, indicated by negative leukocyte esterase and no microscopic white blood cells, has excellent negative predictive value for ruling out UTI 1

The American Academy of Pediatrics recommends that children with fever, irritability, or poor feeding be evaluated for UTI, and that urine culture be obtained before starting antibiotics 3
The American College of Emergency Physicians recommends that physicians determine if symptoms consistent with UTI are present, such as dysuria, frequency, urgency, fever, or gross hematuria, before initiating antimicrobial therapy 1

The Infectious Diseases Society of America recommends trimethoprim/sulfamethoxazole as a first-line treatment for uncomplicated UTI in adults, with a dosage of 4 teaspoonfuls (20 mL) every 12 hours for 10-14 days 1
The American Academy of Pediatrics recommends trimethoprim/sulfamethoxazole as a first-line treatment for UTI in children, with a dosage of 40 mg/kg sulfamethoxazole and 8 mg/kg trimethoprim per 24 hours, given in two divided doses every 12 hours for 10 days 6

The American Geriatrics Society recommends against treating asymptomatic bacteriuria in older adults, even with positive leukocyte esterase, unless specific urinary symptoms are present 1
The American Academy of Pediatrics recommends that febrile infants and young children with a positive test result for leukocyte esterase be evaluated for UTI, and that urine culture be obtained before starting antibiotics 4