Urinalysis and Body Fluids Quiz

Questions and Answers

What role does the proximal tubule primarily play in nephron function?

Concentration of urine.

Reabsorption of glucose and salts. (correct)

Filtration of blood plasma.

Secretion of H+ ions.

Which structure of the kidney is involved in the final regulation of urine concentration?

Distal tubule (correct)

Proximal tubule

Cortex

Medulla

Which of the following substances is primarily secreted into the nephron?

Glucose

H+ ions (correct)

Salts

Bicarbonate

In the nephron, which part is primarily responsible for filtering the blood?

Glomerulus Signup and view all the answers

What process occurs in the medulla of the kidney?

Concentration of urine Signup and view all the answers

Which component of the nephron is primarily involved in the reabsorption of salts?

Proximal tubule Signup and view all the answers

What is the primary function of the Proximal Tubule?

Reabsorbs water, sodium chloride, and glucose Signup and view all the answers

Which statement about the Loop of Henle is correct?

The ascending loop reabsorbs solutes but is impermeable to water Signup and view all the answers

What factors contribute to polyuria?

Diabetes insipidus and certain diuretics Signup and view all the answers

Which substance is primarily secreted by the Distal and Collecting Tubules?

Potassium Signup and view all the answers

At what concentration does glucose become a threshold substance for reabsorption in the Proximal Tubule?

Between 160-180 mg/di Signup and view all the answers

Which of the following is NOT absorbed by the Proximal Tubule?

Sulfates Signup and view all the answers

What is the normal urine volume range for a healthy adult?

1200-1500 ml/day Signup and view all the answers

Which ions are primarily exchanged for sodium ions in the Distal and Collecting Tubules?

Potassium ions Signup and view all the answers

What is the primary functional unit of the kidney?

The nephron Signup and view all the answers

How many nephrons are approximately present in each kidney?

Roughly 1 million Signup and view all the answers

Which of the following substances are included in the glomerular filtrate?

Glucose and amino acids Signup and view all the answers

What is the approximate filtration rate of renal plasma?

120 ml/min Signup and view all the answers

What type of substances does the nephron selectively filter from plasma?

Substances less than 70,000 MW Signup and view all the answers

Which components make up the nephron structure?

Glomerulus and renal tubules Signup and view all the answers

Which of the following correctly describes the composition of the glomerular filtrate?

Includes urea and ammonia Signup and view all the answers

What is the primary role of the glomerulus in the nephron?

Filtering the blood to form urine Signup and view all the answers

What is indicated by elevated plasma concentrations of B2-Microglobulin?

Reduced glomerular filtration rate (GFR) Signup and view all the answers

Which laboratory finding is commonly associated with acute glomerulonephritis?

RBC casts Signup and view all the answers

What is a disadvantage of using Cystatin C as a marker for GFR monitoring?

It is higher in cost than creatinine clearance Signup and view all the answers

What finding is typically present in chronic pyelonephritis?

Positive leukocyte esterase Signup and view all the answers

Which symptom is most associated with nephrotic syndrome?

Free fat droplets Signup and view all the answers

Which laboratory finding could indicate chronic glomerulonephritis?

0cc to few RBC casts Signup and view all the answers

Which condition is characterized by turbid urine, positive nitrite, and bacteria?

Acute pyelonephritis Signup and view all the answers

What does a low concentration of creatinine clearance suggest?

Reduced glomerular filtration rate (GFR) Signup and view all the answers

What is the purpose of measuring creatinine in a 24-hour urine specimen?

To assess the adequacy of urine collection Signup and view all the answers

Which of the following correctly describes the formula for creatinine clearance?

Creatinine Clearance = U x V / P Signup and view all the answers

What is the normal creatinine clearance value considered for adults?

120 ml/min Signup and view all the answers

What role does human chorionic gonadotropin (hCG) play in pregnancy testing?

It is a marker for confirming pregnancy Signup and view all the answers

At what point can hCG be detected in a woman's serum after ovulation?

8-10 days Signup and view all the answers

Which factor must be corrected when calculating kidney clearance based on body size?

Body Surface Area Signup and view all the answers

In the context of creatinine clearance, what does the symbol 'V' represent?

Volume of urine over time Signup and view all the answers

What are the components of human chorionic gonadotropin (hCG)?

Alpha and beta subunits Signup and view all the answers

What is the calculated creatinine clearance based on the given urine and plasma creatinine values?

65 ml/min Signup and view all the answers

Which condition is indicated by the presence of many oval fat bodies and moderate fatty, waxy, and granular casts in the urine?

Nephrotic syndrome Signup and view all the answers

An abnormally high specific gravity in urine could indicate which of the following conditions?

Dehydration Signup and view all the answers

What condition is most likely indicated by cerebrospinal fluid showing elevated protein, normal glucose, and lymphocytes?

Viral meningitis Signup and view all the answers

What does a urine volume of 1.5 L suggest in the context of kidney function?

Normal kidney function Signup and view all the answers

What is the significance of finding 0-2 RBCs per high power field in a urinalysis?

Normal finding Signup and view all the answers

What does the presence of hyaline casts in urine typically indicate?

Normal concentrate ability Signup and view all the answers

A US ratio of 2.7 in a pregnancy test suggests which of the following?

Fetal lung maturity Signup and view all the answers

What does a turbid pericardial fluid most likely indicate?

Infection or malignancy Signup and view all the answers

A bloody pericardial fluid sample can be associated with which condition?

Cardiac puncture Signup and view all the answers

Which of the following is NOT typically associated with high glucose levels in body fluids?

Bacterial infection Signup and view all the answers

Chylous fluid accumulation is most likely influenced by which condition?

Malignancy Signup and view all the answers

Which of the following cell types is predominant in a pericardial fluid analysis indicating bacterial endocarditis?

Neutrophils Signup and view all the answers

What does a milky appearance in pericardial fluid typically indicate?

Lymphatic drainage Signup and view all the answers

In the context of peritoneal fluid, what do high neutrophil counts indicate?

Peritonitis Signup and view all the answers

Which condition is associated with CEA levels to be elevated in body fluids?

Malignancy Signup and view all the answers

What is the most frequently used supravital stain in microscopic examination?

Sternheimer-Malbin Signup and view all the answers

Which abnormal urine constituent may indicate glomerular damage?

Red blood cells Signup and view all the answers

What is the major constituent of casts found in urine sediment?

Uromodulin Signup and view all the answers

Which factor does NOT influence cast formation?

Blood volume Signup and view all the answers

The presence of which of the following in urine is likely related to fat or triglyceride confirmation?

Oil Red O Signup and view all the answers

Which of the following is the normal range for red blood cells per high power field (rbc/hpf) in urine sediment?

0-2 Signup and view all the answers

Which cellular characteristic change can occur in red blood cells due to alterations in pH?

Ghosting Signup and view all the answers

What is the maximum normal count of white blood cells per high power field (wbc/hpf) in urine sediment?

0-5 Signup and view all the answers

Study Notes

Renal Anatomy and Function

Nephrons are the major functional units of the kidney, with approximately 1 million present in each kidney.
The nephron comprises the glomerulus and renal tubules, playing a critical role in filtering blood.
Glomeruli act as a non-selective filter for plasma substances with a molecular weight of less than 70,000.

Glomerular Filtration

The filtration rate is approximately 120 ml/min, which amounts to about one-fifth of renal plasma flow.
Glomerular filtrate includes water, glucose, electrolytes, amino acids, urea, uric acid, creatinine, and ammonia.

Tubular Reabsorption and Secretion

Proximal Tubule:
- Reabsorbs water, sodium chloride, bicarbonate, potassium, calcium, amino acids, phosphates, protein, and glucose.
- Glucose is a threshold substance reabsorbed at concentrations of 160-180 mg/dL or lower.
- Secretes sulfates, glucuronides, hydrogen ions, and drugs.
Loop of Henle:
- Descending Limb: Primarily reabsorbs water with no solutes.
- Ascending Limb: Reabsorbs solutes like sodium, chloride, calcium, and magnesium without reabsorbing water.
Distal and Collecting Tubules:
- Reabsorbs sodium while secreting potassium, ammonia, and hydrogen ions.
- Potassium ions are exchanged for sodium ions during the process.

Normal urine volume averages between 1200-1500 ml/day.
Polyuria: Urine output greater than 2500 ml/day, potentially caused by:
- Diabetes insipidus
- Diabetes mellitus
- Diuretic use
- Caffeine, alcohol, or excessive water intake.
Oliguria: Defined as urine output lower than normal, which may indicate underlying health issues (not specified in the text).

Microscopic Examination and Stains

Sternheimer-Malbin: Most commonly used supravital stain.
Sudan III or Oil Red O: Confirms presence of fat or triglyceride.

Normal Urine Sediment Constituents

Red blood cells (RBC): 0-2/hpf.
White blood cells (WBC): 0-5/hpf.
Hyaline casts: 0-2/lpf.
Slight mucus presence.

Abnormal Urine Constituents

Red Cells: Indicate possible glomerular damage, menstrual contamination, may alter due to pH and osmotic pressure.
Cast Formation Factors:
- pH, tubular output, solute concentration (increased specific gravity), protein levels.

Types of Casts

Hyaline Casts: Most frequently encountered in urine.

Urine Collection and Creatinine Clearance

24-hour urine specimen for accurate analyses; creatinine > 1 mg/dl indicates proper collection.
Mathematical Formula:
- Creatinine Clearance = (U x V) / P
  - U = Urine creatinine concentration (mg/dL)
  - V = Urine volume (ml/time in minutes)
  - P = Plasma creatinine concentration (mg/dL).
Normal Creatinine Clearance for adults is approximately 120 ml/min; adjustments needed for age and body surface area.

Pregnancy Testing

hCG: A glycoprotein secreted by the placenta, rises rapidly in serum/urine during pregnancy; detectable 8-10 days post-ovulation.

Renal Function Markers

B2-Microglobulin: Indicative of renal tubular function and reduced glomerular filtration rate (GFR).
Cystatin C: Potentially better than creatinine for GFR detection but costlier.

Laboratory Findings and Conditions

Acute Glomerulonephritis: Presents with gross hematuria, smoky turbidity, RBC casts, and waxy casts.
Chronic Glomerulonephritis: Hematuria with variable casts.
Acute Pyelonephritis: Turbid urine, positive nitrite, positive leukocyte esterase, WBC casts, and bacteria.
Chronic Pyelonephritis: Similar findings with fewer WBC casts.
Nephrotic Syndrome: Presence of "free" fat droplets and lymphocytes.

Pericardial and Peritoneal Fluid Analysis

Pericardial Cavity: Fluid can be turbid (infection), bloody (tumor or cardiac puncture), or milky (lymphatic drainage).
Peritoneal Cavity: Turbid (peritonitis, cirrhosis), bloody (trauma), or milky fluids.

Additional Diagnostic Considerations

Urine creatinine and plasma creatinine indicative of renal function.
Specific gravity abnormalities could indicate chronic renal disease or diabetes insipidus.
Cerebrospinal fluid revealing increased protein with normal glucose may indicate viral meningitis.

Example of Calculating Creatinine Clearance

Given:
- Urine creatinine: 500 mg/L
- Plasma creatinine: 8 mg/L
- Urine volume: 1.5 L.
Resulting creatinine clearance would be calculated based on the formula provided.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on urinalysis and body fluids with this quiz. Focus on critical elements such as kidney functions and nephron structures. Ideal for students studying renal physiology or clinical lab sciences.