Obtaining and Preparing the Specimen
A clean-catch midstream urine specimen should be obtained. As described earlier, uncircumcised men should retract the prepuce and cleanse the glans penis before voiding. It is more difficult to obtain a reliable clean-catch specimen in females because of contamination with introital leukocytes and bacteria. If there is any suspicion of a UTI in a female, a catheterized urine sample should be obtained for culture and sensitivity.
If possible, the first morning urine specimen is the specimen of choice and should be examined within 1 hour.
Examination under the microscope at a powerful magnification could give us vital information regarding the presence of various elements, useful in differential diagnosis of different conditions. The aim is always to rule out cancerous conditions.
We are looking for:
- Erythrocytes, Circular erythrocytes, Leukocytes
- Epithelial cells are commonly observed in the urinary sediment. Squamous cells are frequently detected in female urine specimens and are derived from the lower portion of the urethra, trigone of postpubertal females, and the vagina.
- Transitional epithelial cells may arise from the remainder of the urinary tract / when they have certain appearance they could help us to diagnose urothelial cancer. This investigation is proposed as screening for smokers and for those that undergo follow-up for urothelial tumors.
- Renal tubular cells (very rare)
A cast is a protein coagulum that is formed in the renal tubule and traps any tubular luminal contents within the matrix.
Tamm-Horsfall mucoprotein casts, hyaline casts, Red blood cell casts, White blood cell casts, Casts with other cellular elements, Granular and waxy, Fatty casts
Identification of crystals in the urine is particularly important in patients with stone disease, because it may help determine the etiology.
The finding of any bacteria in a properly collected midstream specimen from a male should be further evaluated with a urine culture.
Trichomonas vaginalis is a frequent cause of vaginitis in women and occasionally of urethritis in men.
Schistosoma hematobium is a urinary tract pathogen that is not found in Europe or N. America, but is extremely common in countries of the Middle East and North Africa. Examination of the urine shows the characteristic parasitic ova with a terminal spike.
Expressed Prostatic Secretions