Basic Guidelines to Urine Microscopy Interpretation

Microscopic Urinalysis

● Used to confirm and further define a positive dipstick urinalysis

● Will provide quantity of bacteria

● Allows for eventual speciation and sensitivity testing to be completed, in order to guide therapy

● Often used in patients with: – Recurrent infection – Prior infection unresolved with antibiotics – Signs/symptoms of an upper urinary tract infection – Complicated UTIs

● WBC             – Normal: 0 – 5 per hpf • Men usually have < 2/hpf; women usually have < 5/hpf

                        – Presence of elevated WBCs indicates the body may be fighting infection in the urinary tract

● RBC             – Normal: 0 – 1 per hpf

             – Presence indicates damage to urinary tract (e.g., infection, physical trauma, etc.)

● Bacteria       – Normal: negative

 – Presence of bacteria is not always predictive of a UTI (ex. asymptomatic bacteriuria, catheter colonization)

            – Must use in conjunction with other factors Microscopic Urinalysis

● Epithelial cells – Squamous epithelial cells • Normal: 0 – 2 per hpf • Large numbers may indicate a poor sample (contamination)

 – Renal epithelial cells • Normal: 0 – 1 per hpf • Large numbers may indicate renal tubular injury

● Crystals and casts – Typically indicative of inflammation, infection, or injury in the urinary tract