Bacteria in urine can be elongated (rods) or round (cocci), more precise differentiation through the sediment is usually not possible. These microorganisms may be completely stationary or make small short movements ("brownish movement"). The presence of bacteria is often accompanied by the presence of leukocytes (pyuria). More than >20 bacteria per field of view (400x magnification) is referred to as bacteriuria. The most common cause is urinary tract infection.