After centrifugation of the urine specimen, the macroscopic appearance of the sedimentation can offer certain clues about the nature of the urinary sediment. Color is by far the most important characteristic to define different sedimentations, but other features…
In order to interpret your findings after collecting and preparing a urine specimen for microscopy you must obtain a high quality image. If you are not able to clearly see what you’re examining, it may be quite difficult…
Several types of organisms can be identified in the urine sediment. Bacteria, fungi, and parasites are 3 classes of microorganims that can be found. 1. Bacteria Rods and cocci can be identified in the urine sediment and urinary…
Most urinary casts have a fairly homogenous aspect throughout their entirety and are clearly classifiable as either hyaline, granular (with all their variants), waxy, or of some cellular nature. However, in many instances urinary casts are not homogenous…
Crystals are a frequent finding in the urinary sediment. Besides microcrystalline deposits (amorphous phosphates and urates), the most common types of crystals in my practice are: 1. CaOxalate dihydrate (COD) 2. CaOxalate monohydrate (COM) 3. Uric acid …
BK virus (BKV) is a DNA virus that infects up to 90% of the adult population. After initial exposure in childhood, the virus becomes latent in urothelial tissues. In transplant patients, BKV can reactivate in the context of…
White blood cells (WBC’s) in the urine may occur as a result of infection or inflammation anywhere in the urinary tract and the segmented polymorphonuclear neutrophil is the type most often encountered. These WBC’s are identified by the…
Perhaps that most highly sought finding in urinary sediment microscopy is the presence of granular casts. In clinical grounds, granular casts are typically associated with acute tubular injury (ATI) and guide the differentiation between prerenal and overt tubular…
The use of urine sediment analysis is important for the diagnosis of glomerular hematuria. Red blood cells (RBC) casts, beautifully illustrated by @jrseltzer in last month’s post, usually confirm glomerular hematuria – but this is a rather special…
Red Blood Cell (RBC) Casts:RBC casts (Fig. 1) are an important finding in the urinary sediment and most often signify the presence of a proliferative glomerulonephritis or vasculitic process. Although less common, RBC casts may also be seen…