Synonym: Microscopic Urinalysis
FEME stands for Full Examination, Microscopic Examination. Urine FEME is also referred to as Microscopic Urinalysis. How is it done? A sample of well-mixed urine (usually 10-15 ml) is centrifuged in a test tube at relatively low speed (about 2000-3,000 rpm) for 5-10 minutes which produces a concentration of sediment (cellular matter) at the bottom of the tube. The fluid on top is poured off to a volume of 0.2 ml to 0.5 ml left inside the tube. The sediment is resuspended in the remaining urine by flicking the bottom of the tube several times. A drop of resuspended sediment is poured onto a glass slide and a thin slice of glass (a coverslip) is placed over it. The sediment is first examined under low power to identify crystals, casts, squamous cells, and other large objects. "Casts" are plugs of material which came from individual tubules. The number of casts seen are usually reported as number of each type found per low power field (LPF). For an example: "5-10 hyaline casts/LPF." Since the number of elements found in each field may vary considerably from one field to the next, several fields are averaged. Then, examination is carried out at high power to identify crystals, cells, and bacteria. The various types of cells are usually described as the number of each type found per average high power field (HPF). For example: "1-5 WBC/HPF."