What are cholesterol crystals?
A cholesterol crystal is a solid, crystalline form of cholesterol found in gallstones and atherosclerosis. Gallstones occurring in industrialized societies typically contain more than 70-90% cholesterol by weight, much of which is crystalline.
What causes cholesterol crystals in synovial fluid?
It appears that several local factors such as defective drainage, local destruction, increased permeability of synovial membrane, and intraarticular (bursal) bleeding are possible etiologies.
What are birefringent crystals in synovial fluid?
Corticosteroid crystals are birefringent crystals that can be found in some patients’ joint fluids following a corticosteroid injection and sometimes can lead to false positives in gout diagnosis. Their irregular shape provides a means to differentiate them from MSU crystals.
What is negatively birefringent crystals?
Negatively birefringent urate crystals are seen on polarizing examination in 85% of specimens. Microscopic analysis in pseudogout shows calcium pyrophosphate (CPP) crystals, which appear shorter than MSU crystals and are often rhomboidal.
Do cholesterol crystals polarized?
Cholesterol crystals are large, plate-like crystals with notched corners characterized by intense birefringence under polarized light.
What is the appearance of cholesterol crystals under the microscope?
Cholesterol crystals may be seen in renal tubular disease. These crystals look like plates of glass, sometimes with a notch out of one corner. Under polarized light, they exhibit a stained glass effect. These crystals are rarely seen unless the specimen has been refrigerated, because the lipids remain in droplet form.
Are cholesterol crystals birefringent?
Cholesterol crystals are typically large (5–100 μm) plate-like crystals which are strongly birefringent (with either positive or negative elongation). Occasionally synovial fluid examination reveals long and rod-shaped or curved, crecent-shaped cholesterol crystals.
Is monosodium urate a birefringence?
Monosodium urate crystals are described as having negative birefringence; however, under direct polarized light they appear much brighter than the CPPD crystals which are referred to as having positive birefringence.
When do you see cholesterol crystals in urine?
Cholesterol crystals can be found in both neutral and acid urine. They may be caused by renal tubular disease, which can lead to renal failure if left untreated. Treatment may involve alkali therapy to help treat chronic metabolic conditions, like renal tubular disease.
Why do cholesterol crystals have a notched corner?
Cholesterol Crystals. These crystals are characterized by broad plates with a notched corner, created by their propensity to adhere to one another’s surfaces. They are variably and mildly birefringent. The differing colors are due to the rotation of light by the crystals under compensated polarized light microscopy.
How are radiographic dye crystals similar to cholesterol?
Radiographic Dye Crystals • Similar to cholesterol in appearance • Associated with markedly elevated SG Radiographic contrast media, meglumine diatrizoate (Renografin), appearing somewhat like cholesterol, X400 Radiographic contrast media (meglumine diatrizoate) X400
What kind of crystals are found in olecranon bursa?
The aspirate of an effusion from the olecranon bursa reveals cholesterol crystals (×400). These crystals are characterized by broad plates with a notched corner, created by their propensity to adhere to one another’s surfaces. They are variably and mildly birefringent.
What kind of crystals are found in nephrotic syndrome?
• Found in lipid disorders, nephrotic syndrome • Rectangular plates with notched corners • Birefringent • Seen in conjunction with fatty casts, oval fat bodies and protein Cholesterol crystals. Notice the notched corners (X 400) Radiographic Dye Crystals • Similar to cholesterol in appearance • Associated with markedly elevated SG