RMA Urinalysis 1 — Questions and Answers

Question 1: What is the normal pH range for urine?

3.0 to 5.0
4.5 to 8.0 (Correct answer)
7.35 to 7.45
8.5 to 10.0

Correct answer: 4.5 to 8.0

Normal urine pH ranges from 4.5 to 8.0, with an average of approximately 6.0. Urine pH reflects the kidneys' role in maintaining the body's acid-base balance.

Urine pH is measured as part of a routine urinalysis dipstick analysis. Normal urine pH ranges from 4.5 to 8.0 depending on diet, medications, and metabolic status. Acidic urine (pH below 6) may indicate metabolic acidosis, respiratory acidosis, a high-protein diet, or urinary tract infections with certain organisms. Alkaline urine (pH above 7) can result from vegetarian diets, urinary tract infections with urease-producing bacteria (such as Proteus mirabilis), or metabolic alkalosis. Medical assistants performing urinalysis must accurately read and record pH results as part of a complete urine chemical analysis.

Question 2: Which urine specimen collection method is used to obtain a sterile urine sample for culture and sensitivity testing?

First morning void
Random specimen
24-hour urine collection
Clean-catch midstream specimen (Correct answer)

Correct answer: Clean-catch midstream specimen

A clean-catch midstream specimen is the preferred non-invasive method for obtaining a urine sample suitable for culture and sensitivity testing, minimizing contamination from skin flora.

A clean-catch midstream specimen reduces the risk of contaminating the sample with normal urethral or perineal flora. The patient (or medical assistant) cleans the urethral meatus with antiseptic wipes, begins voiding into the toilet to flush out the urethra, and then collects the midstream urine into a sterile container without stopping the flow. For culture and sensitivity testing, the specimen must be transported to the lab within 30 minutes or refrigerated. Medical assistants play a key role in instructing patients on proper clean-catch technique to ensure accurate culture results.

Question 3: On a urine dipstick test, a positive result for nitrites most likely indicates:

Kidney stones
Bacterial infection in the urinary tract (Correct answer)
Diabetes mellitus
Dehydration

Correct answer: Bacterial infection in the urinary tract

A positive nitrite test on a urine dipstick indicates the presence of gram-negative bacteria that convert urinary nitrates to nitrites, suggesting a urinary tract infection (UTI).

Many gram-negative bacteria such as Escherichia coli, Klebsiella, and Proteus contain the enzyme nitrate reductase, which converts dietary nitrates filtered into urine to nitrites. A positive nitrite test on urinalysis is therefore a strong indicator of a bacterial UTI, particularly when combined with a positive leukocyte esterase result (indicating white blood cells). A negative nitrite result does not rule out infection because not all bacteria produce nitrites (e.g., Staphylococcus saprophyticus). Medical assistants performing urinalysis should document and report both nitrite and leukocyte esterase results together.

Question 4: What does specific gravity measure in a urine sample?

The amount of protein excreted per day
The concentration of solutes compared to pure water (Correct answer)
The presence of glucose in the urine
The acidity or alkalinity of the urine

Correct answer: The concentration of solutes compared to pure water

Specific gravity measures the density and concentration of dissolved substances (solutes) in urine relative to pure water, reflecting the kidneys' ability to concentrate or dilute urine.

Urine specific gravity reflects the kidneys' concentrating ability. Normal specific gravity ranges from 1.005 to 1.030. A high specific gravity (above 1.030) indicates concentrated urine and may suggest dehydration, decreased fluid intake, or the syndrome of inappropriate antidiuretic hormone (SIADH). A low specific gravity (below 1.005) indicates dilute urine and may suggest overhydration, diabetes insipidus, or renal tubular dysfunction. Specific gravity is measured via urine dipstick, refractometer, or urinometer. Medical assistants must be proficient in performing and interpreting specific gravity measurements.

Question 5: Which of the following is an abnormal finding when examining urine under a microscope?

0–2 red blood cells per high power field
0–5 white blood cells per high power field
More than 10 bacteria per high power field (Correct answer)
1–2 hyaline casts per low power field

Correct answer: More than 10 bacteria per high power field

More than 10 bacteria per high power field in urine is an abnormal finding suggesting bacteriuria, which may indicate a urinary tract infection.

In microscopic urinalysis, the following are considered within normal limits: 0–5 RBCs/hpf, 0–5 WBCs/hpf, 0–2 hyaline casts/lpf, rare squamous epithelial cells, and no significant bacteria. More than 10 bacteria per high power field is considered clinically significant bacteriuria, especially when accompanied by pyuria (excess WBCs). Greater than 5 WBCs/hpf is pyuria, suggesting UTI or kidney inflammation. Greater than 5 RBCs/hpf (hematuria) may suggest kidney stones, glomerulonephritis, or bladder cancer. Medical assistants performing microscopic urinalysis must be familiar with these reference ranges.

Question 6: What is glucosuria and what does it typically indicate?

The presence of blood in the urine, typically indicating kidney damage
The presence of glucose in the urine, typically indicating elevated blood glucose levels (Correct answer)
Excess protein in the urine, typically indicating nephrotic syndrome
The presence of ketones in the urine, typically indicating starvation or uncontrolled diabetes

Correct answer: The presence of glucose in the urine, typically indicating elevated blood glucose levels

Glucosuria (also spelled glycosuria) is the presence of glucose in the urine, which typically occurs when blood glucose levels exceed the renal threshold of approximately 180 mg/dL.

Under normal conditions, all glucose filtered by the glomerulus is reabsorbed in the proximal tubule, so urine contains no glucose. When blood glucose levels exceed the renal threshold (approximately 180 mg/dL), the reabsorptive capacity of the proximal tubule is exceeded and glucose 'spills' into the urine. Glucosuria is most commonly associated with diabetes mellitus (especially uncontrolled Type 1 or Type 2 diabetes) but can also occur transiently after a high-carbohydrate meal or with certain medications. Medical assistants should recognize glucosuria on dipstick testing and ensure the result is promptly communicated to the physician.

RMA Urinalysis 1

What is the normal pH range for urine?