Waxy casts have a smooth consistency but are more refractile and therefore easier to see in a regular wet sediment preparation of urine compared to hyaline casts. They commonly have squared off ends, as if brittle and easily broken, and also have smooth parallel-sided borders.

Waxy casts indicate tubular injury of a more chronic nature than granular or cellular casts and are always of pathologic significance.

Cellular casts most commonly result when disease processes such as ischemia, infarction, or nephrotoxicity cause degeneration and necrosis of tubular epithelial cells. The presence of these casts indicates acute tubular injury but does not indicate the extent or reversibility of the injury.

A common scenario is the patient with decreased renal perfusion and oliguria secondary to severe dehydration. Ischemic injury results in degeneration and sloughing of the epithelial cells. The resulting casts often are prominent in urine produced following rehydration with fluid therapy. The restoration of urine flow "flushes" numerous casts out of the tubules.

Triple phosphate crystals
 Though they can be found in urine of any pH, their formation is favored in neutral to alkaline urine.

Urinary tract infection with urease-positive bacteria

Calcium oxalate

 They can occur in urine of any pH. The crystals vary in size from quite large to very small. In some cases, large numbers of tiny oxalates may appear as amorphous unless examined at high magnification.

calcium phosphate: 

*seen in normal alkaline urine