Analysis of Urine & Other Body Fluids (Clinical Microscopy)

Comprehensive practice flashcards matching vocabulary terms and strict transcript definitions covering safety, renal physiology, urinalysis, sediment microscopy, amniotic fluid, CSF, semen, synovial fluid, serous fluid, and fecalysis.

Chain of Infection

A continuous link required for the transmission of microorganisms, composed of six components: infectious agent, reservoir, exit portal, mode of transmission, entry portal, and susceptible host.

1:10 Sodium Hypochlorite

A disinfectant solution prepared by mixing 1 part sodium hypochlorite to 9 parts water; remains effective for 1 month and is used daily for disinfecting countertops, biological spills, and laboratory sinks.

NFPA Blue Quadrant

The section of the National Fire Protection Association hazard classification diamond that designates health hazards, graded from 0 (normal material) to 4 (deadly).

RACE

The acronym outlining the procedural steps to follow when a fire is discovered: Rescue anyone in immediate danger, Activate the institutional fire alarm system, Contain the fire by closing doors, and Extinguish the fire if possible or Evacuate.

PASS

The operational sequence for using a fire extinguisher: Pull the pin, Aim at the base of the fire, Squeeze the handles, and Sweep the nozzle side to side.

Class A Fire

A fire involving ordinary combustibles such as paper, cloth, rubbish, plastic, and wood, extinguishable by water, dry chemical, or loaded steam.

Nephron

The basic structural and functional unit of the kidney, totaling $1\text{ million to }1.5\text{ million}$ per kidney, consisting of a glomerulus and renal tubules.

Glomerulus

The working portion of the kidney consisting of a coil of approximately 8 capillary lobes within Bowman's capsule that serves as a non-selective filter for substances with a molecular weight of $<10,000\,\text{daltons}$.

Renal Threshold for Glucose

The plasma concentration of glucose ($160\text{--}180\,\text{mg/dL}$) at which active tubular transport ceases and glucose begins to appear in the urine.

Antidiuretic Hormone (ADH)

A hormone (vasopressin) that regulates water reabsorption in the distal convoluted tubule and collecting duct; its deficiency leads to Diabetes Insipidus, while its excess results in SIADH.

Renal Tubular Acidosis (RTA)

A clinical condition marked by the failure of the kidneys to produce an acid urine due to an impaired ability to secrete hydrogen ions.

Inulin Clearance Test

The exogenous clearance test recognized as the gold standard and reference method for evaluating glomerular filtration ($\text{MW}: 5,200\,\text{Da}$).

Isosthenuria

A fixed urine specific gravity of $1.010$, representing urine with the same osmolality as protein-free plasma filtrate.

First Morning Urine Specimen

The most concentrated and acidic urine collection, voided immediately on rising from sleep; ideal for routine urinalysis, pregnancy testing, cytodiagnostic testing, and evaluating orthostatic proteinuria.

Three-Glass Technique

A urine collection procedure used to diagnose prostatic infection, where prostatitis is indicated if the third specimen (post-prostatic massage) shows a WBC and bacteria count 10 times greater than the first voided portion.

Chain of Custody

A process providing documented proof of proper sample identification and unbroken handling from the time of drug specimen collection until laboratory results are issued.

Polyuria

An abnormal increase in daily urine volume defined as $>2000\,\text{mL/24 hrs}$ (Henry) or $>2.5\,\text{L/day}$ (Strasinger) in adults.

Oliguria

A marked decrease in daily urine output defined as $<500\,\text{mL/24 hrs}$ (Henry) or $<400\,\text{mL/day}$ (Strasinger) in adults.

Anuria

The complete cessation of urine flow, defined quantitatively as an output of $<100\,\text{mL/24 hrs}$.

Urochrome

The major yellow pigment responsible for the normal color of urine, whose excretion is directly proportional to metabolic rate.

Uroerythrin

A pink or red pigment derived from melanin metabolism that imparts a brick dust appearance by depositing on amorphous urate and uric acid crystals.

Protein Error of Indicators

The principle of reagent strip protein testing where certain pH indicators (e.g., tetrabromphenol blue) change color at a constant pH ($3.0$) in the presence of protein by accepting hydrogen ions.

Bence-Jones Protein

Monoclonal immunoglobulin light chains produced in multiple myeloma that precipitate in urine when heated to $40\text{--}60^\circ\text{C}$ and redissolve when boiled at $100^\circ\text{C}$.

Microalbuminuria

The excretion of albumin in the urine at rates of $20\text{--}200\,\mu\text{g/min}$ (or $30\text{--}300\,\text{mg/24 hrs}$), which is undetectable by routine chemical reagent strip testing.

Orthostatic Proteinuria

A benign condition characterized by the occurrence of proteinuria only when standing upright, caused by increased venous pressure on the renal veins, demonstrated by a negative first morning urine and a positive specimen after standing.

Pass-Through Phenomenon

An occurrence in the Clinitest copper reduction assay where glucose levels $>2\,\text{g/dL}$ cause the color to rapidly progress to brick red and reoxidize back to a greenish-brown.

Acetoacetic Acid

The parent ketone body, comprising approximately $20\%$ of total circulating ketone bodies, and the primary analyte detected by sodium nitroprusside reagent strips.

Blondheim's Test

An ammonium sulfate precipitation test ($2.8\,\text{g}$ ammonium sulfate) used to differentiate hemoglobin (which precipitates out) from myoglobin (which remains in solution).

Ictotest

A confirmatory tablet test using p-nitrobenzene-diazonium p-toluenesulfonate that detects urine conjugated bilirubin with a sensitivity of $0.05\text{--}0.1\,\text{mg/dL}$.

Watson-Schwartz Test

A differential extraction test using chloroform and butanol to distinguish urobilinogen from porphobilinogen and other Ehrlich-reactive compounds.

Greiss Reaction

The chemical reaction used on reagent strips to detect nitrite, in which nitrite reacts with an aromatic amine in an acid medium to produce a diazonium salt that forms a pink azo dye.

Addis Count

A quantitative microscopic hemacytometer evaluation of formed elements performed on a $12\text{-hour}$ urine specimen preserved with formalin.

Glitter Cells

Neutrophils in hypotonic urine that swell and demonstrate Brownian movement of their cytoplasmic granules, staining pale blue with Sternheimer-Malbin stain.

Clue Cell

A squamous epithelial cell with a shaggy appearance caused by dense coverage with Gardnerella vaginalis, diagnostic of bacterial vaginosis.

Oval Fat Body

A lipid-containing renal tubular epithelial cell or macrophage that produces a characteristic Maltese cross appearance under polarized light when cholesterol is present.

Bubble Cell

An injured renal tubular epithelial cell displaying non-lipid vacuoles formed by dilation of the endoplasmic reticulum prior to cell death, associated with acute tubular necrosis.

Tamm-Horsfall Protein

A glycoprotein (uromodulin) secreted by renal tubular epithelial cells of the ascending loop of Henle and distal convoluted tubule that forms the core matrix of urinary casts.

Waxy Cast

The final degenerative stage of urinary casts, characterized by a brittle, highly refractile appearance with notched or jagged edges, indicating extreme urinary stasis.

Broad Cast

A cast that is $2\text{--}6$ times wider than an ordinary cast, formed in dilated tubules or collecting ducts and associated with extreme stasis and end-stage renal failure.

Amorphous Urates

Yellow-brown granular crystals seen in acid urine that form a pink macroscopic precipitate (brick dust) and dissolve upon heating to $60^\circ\text{C}$ or adding alkali.

Ammonium Biurate

A normal alkaline crystal displaying a yellow-brown thorny apple morphology, typically found in old urine specimens containing urea-splitting bacteria.

Triple Phosphate

A magnesium ammonium phosphate crystal found in alkaline urine with a prism or coffin-lid appearance that dissolves in dilute acetic acid.

Cystine Crystals

Colorless, highly refractile hexagonal plates found in acid urine of patients with cystinuria, confirmed using the cyanide-nitroprusside reaction.

Leucine Crystals

Yellow-brown oily spheres showing concentric circles and radial striations resembling a tree trunk growth pattern, seen in acid urine in severe liver disease.

Phenylketonuria (PKU)

An inborn error of metabolism caused by a deficiency of phenylalanine hydroxylase, characterized by increased phenylpyruvic acid and a mousy urine odor.

Alkaptonuria

A metabolic disorder caused by the absence of homogentisic acid oxidase, causing urine to darken to brown or black upon standing and exposure to alkaline conditions.

Maple Syrup Urine Disease (MSUD)

An inborn error of branched-chain amino acid metabolism caused by a defect in branched-chain alpha-keto acid dehydrogenase, producing urine with a sweet, caramelized sugar odor.

Lesch-Nyhan Disease

A purine disorder caused by a deficiency of hypoxanthine guanine phosphoribosyltransferase, resulting in hyperuricemia and an orange sand precipitate in infant diapers.

Nephrotic Syndrome

A renal disorder marked by disruption of the podocyte electrical charge barrier, leading to massive proteinuria ($>3.5\,\text{g/day}$), lipiduria, oval fat bodies, and fatty casts.

Telescoped Sediment

A urine sediment containing an simultaneous mixture of cellular, coarsely granular, finely granular, and waxy casts, seen in end-stage renal disease.

Human Chorionic Gonadotropin (hCG)

A hormone produced by placental syncytiotrophoblasts whose beta-subunit confers immunoassay specificity and which reaches peak concentrations during the first trimester.

Fern Test

A diagnostic procedure used to detect premature rupture of membranes (PROM) or early pregnancy based on the microscopic visualization of palm-leaf or fern-like crystallization in air-dried vaginal fluid.

Lecithin/Sphingomyelin (L/S) Ratio

The reference method for evaluating fetal lung maturity using thin-layer chromatography; a ratio of $\ge 2.0$ indicates mature fetal lungs.

Lamellar Body Count (LBC)

An objective assessment of fetal lung maturity using the platelet channel of a hematology analyzer, where a count of $\ge 32,000/\mu\text{L}$ denotes adequate maturity.

Xanthochromia

A pink, orange, or yellow discoloration of cerebrospinal fluid supernatant caused by the presence of hemoglobin degradation products such as oxyhemoglobin and bilirubin.

CSF/Serum Albumin Index

A calculated parameter evaluating the integrity of the blood-brain barrier; an index of $<9$ is normal, whereas values $>30$ indicate severe barrier impairment.

Oligoclonal Bands

Distinct immunoglobulin bands visualized in the gamma region of CSF electrophoresis; the presence of two or more bands in CSF but absent in serum is diagnostic of Multiple Sclerosis.

Limulus Amoebocyte Lysate (LAL) Test

A test employing amoebocyte lysate derived from the blood of the horseshoe crab (Limulus polyphemus) that forms a gel or clot in the presence of Gram-negative bacterial endotoxin.

Sertoli Cells

Specialized supportive nurse cells within the seminiferous tubules that nourish and sustain developing spermatozoa during spermatogenesis.

Kruger's Strict Criteria

A rigorous morphometric evaluation method for sperm structure requiring $>14\%$ normal forms for a specimen to be classified as normal.

Modified Blom's Test

A sperm viability assay using eosin-nigrosin dye, where living spermatozoa with intact membranes exclude the stain and appear bluish-white, while dead cells stain red.

Florence Test

A medico-legal test for the detection of seminal fluid choline using iodine crystals and potassium iodide, producing dark brown rhombic crystals.

Barbiero's Test

A forensic screening test for spermine in semen using saturated picric acid and trichloroacetic acid, which yields yellow leaf-like crystals.

Arthrocentesis

The percutaneous aspiration procedure used to collect synovial fluid from a joint space.

Ropes Test

A mucin clot test assessing synovial fluid hyaluronate polymerization by the addition of $2\text{--}5\%$ acetic acid, grading the firmness of clot formation.

Monosodium Urate (MSU) Crystals

Needle-shaped crystals found in synovial fluid during acute gout that exhibit strong negative birefringence, appearing bright yellow when aligned parallel to the slow axis of a red compensator.

Calcium Pyrophosphate Dihydrate (CPPD) Crystals

Rhombic- or rod-shaped crystals associated with pseudogout that exhibit weak positive birefringence, appearing blue when aligned parallel to the slow axis of a red compensator.

Transudate

A serous effusion resulting from a systemic mechanical disruption in hydrostatic or oncotic pressure across intact membranes, characterized by a fluid-to-serum protein ratio $<0.5$.

Exudate

A serous effusion resulting directly from local membrane damage, infection, inflammation, or malignancy, characterized by a fluid-to-serum protein ratio $>0.5$.

Serum-Ascites Albumin Gradient (SAAG)

A diagnostic calculation (Serum Albumin minus Peritoneal Albumin) where values $\ge 1.1\,\text{g/dL}$ identify transudative ascites of hepatic origin and values $<1.1\,\text{g/dL}$ identify exudative effusions.

Chylous Effusion

A milky pleural fluid caused by thoracic duct obstruction or leakage, containing a predominance of lymphocytes, triglycerides $>110\,\text{mg/dL}$, and absent cholesterol crystals.

Steatorrhea

An abnormal increase in fecal fat excretion exceeding $6\,\text{g/day}$, commonly evaluated qualitatively by Sudan III staining.

Van de Kamer Titration

The gold standard quantitative method for fecal fat measurement, performed on a $72\text{-hour}$ stool sample by alkaline titration with sodium hydroxide.

Creatorrhea

The abnormal excretion of more than 10 undigested, striated muscle fibers per high-power field in feces stained with $10\%$ eosin, seen in pancreatic insufficiency.

Guaiac Fecal Occult Blood Test (gFOBT)

A screening test for hidden gastrointestinal blood and colorectal cancer based on the pseudoperoxidase activity of hemoglobin converting guaiac to a blue-colored compound.

Apt Test

An alkali denaturation test utilizing $1\%\,\text{NaOH}$ to distinguish swallowed maternal blood (HbA denatures yellow-brown) from neonatal gastrointestinal hemorrhage (HbF resists denaturation and remains pink).

D-Xylose Absorption Test

A diagnostic procedure evaluating intestinal mucosal absorption independent of pancreatic enzymes, where low urinary excretion indicates intestinal malabsorption while normal excretion indicates maldigestion.

Pilocarpine Iontophoresis

The sweat-induction method used to collect sweat for measuring chloride and sodium levels, where sweat chloride values $\ge 60\,\text{mEq/L}$ are diagnostic for cystic fibrosis.

Psammoma Bodies

Microscopic structures containing concentric laminated striations of collagen-like material, identifiable in peritoneal fluids associated with ovarian and thyroid carcinomas.