05-Routine Urinalysis & Renal Function Tests

First morning specimen

Which urine specimen is the most concentrated and is best for routine urinalysis, protein detection, low-level substances, and microscopic examination?

Random specimen

Which urine specimen is most commonly used for routine urinalysis and is convenient for patients?

Timed collection

Which urine specimen is used for quantitation of analytes affected by circadian or diurnal variation?

24-hour urine collection

Which timed urine specimen is used to determine the amount of protein lost over 24 hours?

Drug-testing specimen

Which urine specimen follows a standard chain-of-custody procedure?

Suprapubic aspiration

Which urine collection method is preferred for pediatric patients and patients who have difficulty urinating?

Catheter specimen

Which urine specimen is collected using a sterile catheter and can also be used for culture?

Midstream clean-catch

What urine collection method involves cleaning the urethral meatus, voiding the first portion, collecting the middle portion, and voiding the last portion?

Sterile container

What type of container should be used when collecting urine specifically for culture?

2 hours

Within how long after voiding should urine ideally be examined?

Refrigeration

What should be done when urine analysis will be delayed for more than about 1 hour?

Do not freeze

What should NEVER be done to a urine specimen because freezing can cause crystal formation?

20–30 mL

What is the usual recommended urine volume for routine urinalysis?

10–15 mL

What smaller urine volume may be acceptable for adults when automation is used?

3–5 mL

What urine volume may be acceptable for children according to the specimen evaluation section?

3.2% sodium citrate

What anticoagulant is used for coagulation testing rather than routine urinalysis?

Clean, dry container

What type of container is recommended for routine urine collection?

Urethral meatus

What should be cleaned before collecting a midstream clean-catch urine specimen?

Immediate transport

What should be done with a urine specimen after collection to minimize changes in results?

Bacteriologic examination

If only one urine specimen is submitted for multiple laboratory sections, which examination should be performed first to prevent contamination?

Specimen evaluation → gross/physical examination → chemical screening → sediment examination

What is the correct sequence of the four components of routine urinalysis?

Specimen evaluation

Which component of routine urinalysis checks adequacy, labeling, contamination, collection date, and patient identification?

Gross/physical examination

Which component evaluates urine color, clarity, odor, volume, and specific gravity?

Chemical screening

Which component primarily uses reagent strips or dipsticks to test urine analytes?

Urine sediment examination

Which component involves centrifuging urine and microscopically examining the sediment?

Specific gravity

Which urine parameter is most directly useful for assessing urine concentration and concentrating ability?

Color

Which gross characteristic of urine is routinely assessed along with clarity and volume?

Clarity

Which physical characteristic describes whether particulate material can be seen in urine?

Odor

Which urine characteristic is not routinely performed but may provide diagnostic clues when abnormal?

Specific gravity

Which physical parameter has also been incorporated into chemical screening because it can be measured by reagent strips?

Clear straw-colored

What is the normal appearance of urine with no particulate matter?

Hazy

What degree of urine clarity indicates some visible particulate matter while newsprint remains undistorted?

Cloudy

What degree of urine clarity may result from phosphates, urates, WBCs, bacteria, yeast, or spermatozoa?

Turbid

What degree of urine clarity occurs when WBCs, pyuria, bacteria, or spermatozoa make newsprint unreadable?

Milky

What urine appearance may be associated with chyluria or lipiduria?

Chyluria

What condition can cause milky urine because of lymphatic fluid entering the urinary tract?

Lipiduria

What finding involves fat globules in urine and is often associated with nephrotic syndrome?

Urochrome

What is the normal yellow urine pigment whose amount depends on metabolic state?

Uroerythrin

What pink urine pigment attaches to urates and is commonly found in acidic urine?

Urobilin

What dark yellow-orange pigment is an oxidation product of urobilinogen?

Maple syrup

What characteristic urine odor is associated with maple syrup urine disease?

Sweet/fruity

What characteristic urine odor is associated with ketoacidosis?

Mousy/musty

What characteristic urine odor is associated with phenylketonuria?

Rotten fish

What characteristic urine odor is associated with trimethylaminuria?

Sweaty feet

What characteristic urine odor is associated with isovaleric acidemia and glutaric acidemia?

Ammoniacal/fetid

What urine odor may indicate bacterial overgrowth?

Rotten eggs

What urine odor is associated with cystinuria?

Swimming pool/chlorine

What urine odor is associated with Hawkinsinuria?

4.6–8.0

What is the normal urine pH range?

Acidic urine

What type of urine pH is associated with high-protein diets, cranberry intake, systemic acidosis, and diabetic ketoacidosis?

Alkaline urine

What type of urine pH is associated with UTIs, metabolic alkalosis, and some renal calculi?

Methyl red + bromothymol blue

Which double indicators are used in the reagent-strip principle for urine pH?

Freshly voided specimen

What type of specimen should always be used for accurate urine pH measurement?

Albumin

What is the major protein normally found in urine?

150 mg/24 hours

What is the normal maximum amount of protein excreted in urine per 24 hours according to the file?

≥30 mg/dL

What urine protein concentration is considered clinical proteinuria in the file?

Reagent strip

Which protein screening method is particularly sensitive to albumin?

Acid precipitation

Which protein screening method can detect all proteins present in urine?

Functional proteinuria

What type of proteinuria may occur with dehydration, strenuous exercise, CHF, cold exposure, or fever and resolves with rest?

2–3 days

After functional proteinuria caused by strenuous exercise, how long should the patient rest before reevaluation?

Orthostatic proteinuria

What type of proteinuria occurs during the day but not at night, commonly in healthy young adults?

3–5%

Approximately what percentage of healthy young adults may have postural/orthostatic proteinuria?

Glomerular proteinuria

What type of renal proteinuria results from increased glomerular permeability to proteins?

Tubular proteinuria

What type of renal proteinuria results from impaired tubular reabsorption of filtered proteins?

Prerenal proteinuria

What type of proteinuria results from excess proteins in plasma before blood reaches the kidneys?

Postrenal proteinuria

What type of proteinuria results from proteins being added to urine after it leaves the kidneys?

Bence Jones protein

What abnormal urinary protein consisting of monoclonal immunoglobulin light chains is associated with multiple myeloma?

Multiple myeloma

What disease is strongly associated with Bence Jones proteinuria?

Microalbuminuria

What refers to albumin in urine above normal levels but below the detection range of conventional reagent strips?

Micral test

What urine test can detect low levels of albumin and help identify early glomerular damage?

Glucose

Which substance is normally reabsorbed by the renal tubules and is typically absent from urine?

180–200 mg/dL

Approximately what plasma glucose level is the renal threshold above which glucose begins to spill into urine?

Glycosuria

What is the presence of glucose in urine called?

Diabetes mellitus

What is the most important condition causing glycosuria with hyperglycemia?

Fanconi syndrome

What renal tubular disorder can cause glycosuria despite normal blood glucose?

Hyperglycemia

What is the mechanism of glycosuria when blood glucose exceeds the renal threshold?

Tubular impairment

What is the mechanism of glycosuria without hyperglycemia?

Reagent strip

What is a common method for detecting urinary glucose?

Copper reduction test

What older chemical method can detect reducing substances such as glucose in urine?

Ketones

What are products of incomplete fat metabolism that appear in urine when carbohydrate availability or metabolism is inadequate?

Acetoacetic acid, acetone, 3-hydroxybutyrate

What are the three major ketone bodies?

Diabetes mellitus

What major disease can cause ketonuria?

Starvation

What non-diabetic condition can cause ketonuria due to increased fat metabolism?

Keto diet

What type of diet can cause increased urinary ketones?

Dehydration and malnutrition

In children, what conditions may be suggested by significant ketonuria after inability to eat for 24–48 hours?

Nitroprusside

What reagent method can detect urinary ketones?

Hematuria

What term refers to blood or intact RBCs present in urine?

Hemoglobinuria

What term refers to hemoglobin present in urine without necessarily having intact RBCs?

Myoglobinuria

What term refers to myoglobin present in urine, often after muscle injury?

Reagent strip

What chemical method detects blood pigment in urine?

Gross hematuria

What type of hematuria is visible to the naked eye as red or pink urine?

Microscopic hematuria

What type of hematuria requires microscopic examination to detect RBCs?

Clear supernatant + RBC sediment

What centrifugation pattern supports true hematuria?

Red sample after centrifugation

What centrifugation finding suggests myoglobinuria rather than true hematuria?

Kidney stones

What urinary condition can cause hematuria through mechanical injury to the urinary tract lining?

Glomerulonephritis

What renal disease can cause urinary blood?

Pyelonephritis

What renal infection can cause blood in the urine?

Menstruation

What contamination source should be considered when RBCs are found in a female urine specimen?

0.02 mg/dL

What bilirubin value is given as the normal reference in the file?

Conjugated bilirubin

Which form of bilirubin can appear in urine when present in excess in blood?