Red blood cells in the urine may be caused by kidney or bladder injury, kidney stones, a urinary tract infection (UTI), inflammation of the kidneys (glomerulonephritis), a kidney or bladder tumor, or systemic lupus erythematosus (SLE). White blood cells (pus) in the urine may be caused by a urinary tract infection, bladder tumor, inflammation of the kidneys, systemic lupus erythematosus (SLE), or inflammation in the vagina or under the foreskin of the penis.
Depending on the type, casts can mean inflammation or damage to the tiny tubes in the kidneys, poor blood supply to the kidneys, metal poisoning (such as lead or mercury), heart failure, or a bacterial infection.
Large amounts of crystals, or certain types of crystals, can mean kidney stones, damaged kidneys, or problems with metabolism. Some medicines and some types of urinary tract infections can also increase the number of crystals in urine.
Bacteria in the urine mean a urinary tract infection (UTI). Yeast cells or parasites (such as the parasite that causes trichomoniasis) can mean an infection of the urinary tract.
The presence of squamous cells may mean that the sample is not as pure as it needs to be. These cells do not mean there is a medical problem, but your doctor may ask that you give another urine sample.