Question | Answer |
Specific Gravity | (45s) Concentration of urine. Weight of substances in the urine. Assessed by comparing the SG of urine with distilled water. Normal: 1.003-1.035.
False High: glycosuria or proteinuria, because of the increased concentration.
False Low: alkalinity. |
Nitrite | (60s) The presence of nitrites in fresh urine indicate bacterial growth.
False Pos: May be caused by bacterial growth in an old urine specimen or specimen placed in a container found around the house.
False Neg: urine that is abnormal in color. |
Ketones | (40s)Incomplete fatty acid metabolism, when glucose is limited. Starvation, severe vomiting, diarrhea or Pg are present.
False Pos: highly pigmented urine .
False Neg: May occur if bacteria present in the urine and the specimen is not tested immed. |
Blood | (60s)Hemolyzed/non-hemolyzed.
Bleeding into part of urinary tract.Trauma, UTI, renal disease, renal stones.
False Pos: menstrual blood, oxidizing compounds, or peroxidase produced-microbes.
False Neg: formalin, excess nitrates, elev SG or some drugs |
Glucose | (30s)Diabetes mellitus.
False Pos: This test is specific for glucose, meaning no other compound cause a positive result.
False Neg: May be caused by an excess of ascorbic acid, elevated SG, or a high level of ketones. |
Bilirubin | (30s)Hepatitis, liver sclerosis, or obstructive jaundice. Bilirubin is a breakdown product of hemoglobin.
False Pos:Intensely colored urine or certain drugs.
False Neg: Excess ascorbic acid and large amounts of nitrite. Light exposure decreases. |
Protein | (60s)Renal dis.Sm amt phys or emot stress,early renal dis.Sm to mod UTI, kidney stones or acute renal dis.Lg amt adv renal dis; nephrotic syndrome, chronic glomerulonephritis.
False Pos:contaminants/ high pH level.
False Neg:High salt levels. Globulins |
pH (parts hydrogen) | (60s)Acid or alkaline(pH scale of 0-14 0 highest acidity and 14 highest alkalinity or basic). Average pH urine is from 5.0 to 7.0. Indicates kidneys’ ability to maintain normal hydrogen ion concentration and may vary with diet. |
Leukocytes | (2 min)WBC in urine. UTIs. Infection of the kidney, bladder or urethra.
False Pos: vaginal contaminants
False Neg: drugs elevated glucose, high SG or oxalic acid can interfere with the chemical reaction even if WBC are present in the urine. |
Urobilinogen | (60s)Normally, bilirubin is converted to urobilinogen by bacteria and excreted in the feces and urine. Elevated urobilinogen may indicate disease or dysfunction of the heart, spleen or liver. |
Urine pregnancy test (HCG) | (First Morning Specimen preferred)Tests for presence of HCG (human chorionic gonadotropin), and is usually a qualitative test for a negative or positive result: |
Parts of Urinalysis | Physical, Chemical, Microscopic |
Supernatant fluid | Liquid portion of urine discarded after centrifuging |
Urine sediment | Remainder of solid particles remaining after centrifuging urine that is viewed under the microscope. |