Chapter 21

Acute Glomerulonephritis

Sudden inflammation of kidney glomeruli, often post-strep infection; symptoms: hematuria, edema, hypertension.

Acute Kidney Failure

Rapid loss of kidney function due to injury, dehydration, or toxins; may be reversible.

Afferent Arteriole

Blood vessel bringing blood into the glomerulus (wider than efferent → high pressure for filtration).

Aldosterone

Adrenal hormone that increases Na⁺ reabsorption & K⁺ excretion in kidneys (raises BP).

Anuria

No urine output (<100 mL/day); seen in severe kidney failure or obstruction.

Bowman’s Capsule

Cup-shaped structure surrounding the glomerulus; collects filtrate in nephron.

Calyces

Cup-like structures in renal pelvis that collect urine from pyramids.

Chronic Glomerulonephritis

Progressive glomeruli inflammation leading to scarring & kidney failure.

Chronic Renal Failure

Gradual, irreversible loss of kidney function; end-stage requires dialysis/transplant.

Collecting Tubule

Final nephron segment adjusting urine concentration via ADH.

CAKUT

Congenital Anomalies of Kidney & Urinary Tract (e.g., hydronephrosis, renal agenesis).

Cortex

Outer kidney layer containing glomeruli & convoluted tubules.

Cystitis

Bladder inflammation (UTI); symptoms: dysuria, urgency, cloudy urine.

Dialysis

Artificial blood filtration for kidney failure (hemodialysis or peritoneal).

Dialyzer

Machine filter for hemodialysis; removes waste, balances electrolytes.

Distal Convoluted Tubule (DCT)

Nephron section adjusting Na⁺, K⁺, and pH under aldosterone & PTH.

Dysuria

Painful urination (UTI, STI, or kidney stones).

Efferent Arteriole

Blood vessel carrying blood away from glomerulus (narrower → maintains filtration pressure).

ESWL

Extracorporeal Shock Wave Lithotripsy – noninvasive kidney stone treatment using sound waves.

Filtrate

Fluid filtered from blood in glomerulus → becomes urine.

Glomerulus

Capillary cluster in nephron where blood filtration begins.

Hematuria

Blood in urine (UTI, stones, glomerulonephritis, cancer).

Hemodialysis

: Blood filtered externally via dialyzer (3x/week sessions).

Hilum

Kidney indentation where vessels/ureters enter/exit.

Hydronephrosis

Kidney swelling due to urine backup (e.g., ureter obstruction).

Hypospadias

Congenital urethral opening on underside of penis (corrected surgically).

Incontinence

Loss of bladder control (stress, urge, overflow types).

Kidney Dysplasia

abnormal kidney development in fetus; nonfunctional tissue.

Kidney Stones (Renal Calculi)

Hard mineral deposits causing colicky pain, hematuria.

Loop of Henle

Nephron section creating salt gradient for water reabsorption.

Medulla

Inner kidney with pyramids & collecting ducts.

Micturition

Urination; controlled by detrusor muscle (bladder) & sphincters.

Nephron

Functional kidney unit (filters blood, forms urine).

Neurogenic Bladder

Bladder dysfunction from nerve damage (e.g., spinal injury).

Nocturia

Frequent nighttime urination (BPH, diabetes, UTI).

Oliguria

Low urine output (<400 mL/day; dehydration or kidney failure).

Osmoreceptors

Hypothalamic sensors detecting blood osmolarity → trigger ADH release.

Overactive Bladder

Urgency/frequency from involuntary detrusor contractions.

Peritoneal Dialysis

Dialysis using abdominal lining (peritoneum) as filter.

Proximal Convoluted Tubule (PCT)

Nephron section reabsorbing 65% of filtrate (glucose, amino acids, Na⁺).

Pyelitis

Inflammation of renal pelvis (often bacterial).

Pyelonephritis

Kidney infection (fever, flank pain, pyuria); can scar kidneys.

: Pyuria

Pus in urine (UTI, pyelonephritis).

Renal Columns

Cortical tissue between pyramids.

Renal Fascia

Connective tissue anchoring kidneys to abdominal wall.

Renal Papilla

Tip of pyramid draining urine into calyx.

Renal Pelvis

Funnel-shaped urine collection area before ureter.

Renal Pyramids

Triangular medullary regions with collecting ducts.

Renin

Kidney enzyme releasing angiotensin to raise BP (RAAS pathway).

Retroperitoneal

Organs behind peritoneum (kidneys, ureters, pancreas).

: Threshold

Plasma concentration limit for reabsorption (e.g., glucose → spills into urine if exceeded).

Uremia

Toxic buildup of waste in blood (symptom of kidney failure).

Ureters

Tubes carrying urine from kidneys to bladder.

Urethra

Tube expelling urine from bladder (longer in males).

Urinalysis

Urine test for pH, glucose, protein, cells, bacteria.

Urinary Bladder

Stores urine; lined with transitional epithelium.

Urinary Meatus

External urethral opening.

Vesicoureteral Reflux (VUR)

Abnormal urine backflow from bladder to ureters → UTI risk.