Clinical Microscopy and Urine Analysis Laboratory Review

Comprehensive practice flashcards covering microscope mechanics, urine collection methods, preservation techniques, physical characteristics, and chemical screening test principles.

The Microscope

An optical instrument that magnifies the size of the object, used to observe objects that are not visible with the unaided eye.

Galileo Galilei & Zacharias Janssen

The individuals credited with the invention of the microscope.

Anton van Leuwenhoek

The individual with whom the use of the microscope started.

Simple Microscope

A type of microscope that consists of only $1$ biconvex lens.

Compound Microscope

A type of microscope that consists of $2$ or more lenses.

Diopter Adjustment

Found on the left lens; allows changing the focus of one eyepiece to compensate for vision differences between both eyes.

Coarse Adjustment Knob

Brings the specimen image into rough focus; used primarily with Scanning and Low-power objectives; NEVER use in HPO/OIO.

Fine Adjustment Knob

Used with High-power and Oil Immersion objectives to bring the specimen into clearer focus with micro-adjustment control.

Scanning Objective

Objective lens that magnifies the object by $4x$; provides the widest field of view only for locating points of interest.

Low-power Objective

Objective lens that magnifies the object by $10x$.

High-power Objective

Objective lens that magnifies the object by $40x$, used for examining finer details.

Oil Immersion Objective

Objective lens that magnifies the object by $100x$; uses oil to collect more light due to its refractive index.

Parfocal

The ability of a microscope's objective to maintain the same corresponding focus when changing magnification.

Total Magnification Calculation

$\text{Eyepiece Magnification} \times \text{Objective Magnification}$ (e.g., $10x \times 40x = 400x$).

Diaphragm (Iris)

Part of the illumination system that controls the amount of light that reaches the specimen.

Urine

The ultrafiltrate of plasma produced by the kidneys through renal blood flow, glomerular filtration, tubular reabsorption, and tubular secretion.

Urine Composition

Composed of 95\text{%} water and 5\text{%} solutes.

Chloride

The major inorganic solute component in urine.

Urea

The major organic solute component in urine.

First Morning Midstream Clean Catch

The most preferred specimen type; most concentrated and good for recovery of cells/casts or confirming orthostatic proteinuria.

Chain of Custody (COC)

Documentation of proper sample identification from collection to receipt of results, required for drug testing urine specimens.

Three-hour Glass Collection

Method used to determine prostate infection; includes a 3rd glass collected after the prostate is massaged by a urologist.

Thymol

Preservative that preserves glucose and sediments but interferes with acid precipitation tests for protein.

Boric Acid

Keeps pH at about $6.0$; bacteriostatic at $18\text{\text{,}}g/L$; used for culture transport.

Sodium Fluoride

Preservative that prevents glycolysis and is good for drug analyses; inhibits reagent strip tests for glucose, blood, and leukocytes.

Isosthenuria

A condition where the specific gravity of urine is fixed at $1.010$, similar to the initial plasma concentration of the glomerulus.

Polyuria

Abnormal increase in urine secretion, typically $2500\text{\text{,}}mL/day$.

Oliguria

A decrease in normal daily urine output, typically $< 400\text{\text{,}}mL/day$.

Anuria

No urine flow or complete absence of urine excretion.

Phenylketonuria Odor

Mousy-smelling urine.

Maple Syrup Urine Disease Odor

Caramelized sugar or maple syrup-smelling urine.

Trimethylaminuria Odor

Makes urine smell like rotting fish.

Hyposthenuric

Urine with a specific gravity below $1.010$.

Hypersthenuric

Urine with a specific gravity above $1.010$.

Protein Error of pH Indicators

Principle where pH indicators change color because proteins (primarily albumin) act as hydrogen ion acceptors at a constant pH.

Tamm-Horsfall protein (uromodulin)

A type of protein found in urine other than albumin.

Glycosuria/Glucosuria

The presence of glucose in urine, which is a major screening test for diabetes mellitus.

Glucose Reagent Principle

Based on a double sequential enzyme reaction involving glucose oxidase and peroxidase.

Acetoacetic acid

The intermediate product of fat metabolism (20\text{%}) specifically measured in urine by reagent strips using nitroprusside.

Hematuria

The presence of blood in urine resulting in cloudy urine.

Hemoglobinuria

The presence of hemoglobin in urine resulting in clear red/pink urine and red/pink plasma.

Greiss Reaction

The principle employed by reagent strips to detect nitrite in urine.

Leukocyte Esterase

An enzyme released by white blood cells used as a qualitative measure of WBC in the urinary tract.

Ascorbic Acid

The 11th parameter in reagent strips; causes false negative reactions for blood, bilirubin, leukocyte esterase, nitrite, and glucose.