Exam 3 patho - urinary and renal

Filtration 

• The process where blood is pushed through tiny filters in the kidneys called glomeruli.

• Waste, water, and small particles pass through into the tubules, but blood cells and proteins stay in the blood

Reabsorption

• The kidneys take back useful substances like water, glucose, and electrolytes from the filtered fluid into the blood.

• This helps the body keep what it needs.

Secretion

• The kidneys actively move extra wastes, drugs, or chemicals from the blood into the urine.

• This helps remove things that weren’t filtered out the first time.

Excretion 

The final step of urine production, where waste, water, and other substances the body does not need are removed from the body.

Micturition

The medical term for urination, or the process of releasing urine from the bladder.

Glomerular Filtration Rate (GFR)

• The amount of blood filtered by the kidneys each minute.

• It shows how well the kidneys are working

measures how well kidneys filter blood

Autoregulation

The kidney’s natural ability to keep blood flow and GFR steady even when blood pressure changes.

Renin-Angiotensin-Aldosterone System (RAAS)

A hormone system that raises blood pressure and blood volume when they are too low

Erythropoietin

A hormone made by the kidneys that signals the bone marrow to make more red blood cells.

Antidiuretic Hormone (ADH)

A hormone from the brain that tells the kidneys to hold on to water instead of releasing it.

Atrial Natriuretic Peptide (ANP)

A hormone made by the heart that causes the kidneys to release water and salt to lower blood pressure.

Specific Gravity (urine)

A measure of how concentrated urine is.

Blood Urea Nitrogen (BUN)

A blood test that measures how much urea (a waste product from protein breakdown) is in the blood.

Creatinine

• A waste product from muscle use that is filtered out by the kidneys.

• It is one of the best measures of kidney function

Proteinuria

The presence of protein in the urine, which indicates that the kidney’s filters are damaged.

Hematuria

Blood in the urine.

Oliguria

Producing too little urine, usually less than 400 mL per day - low urine

Azotemia

A buildup of nitrogen waste products (such as BUN and creatinine) in the blood due to poor kidney function

Prerenal AKI

A type of acute kidney injury caused by low blood flow to the kidneys

Intrarenal AKI

Acute kidney injury caused by damage inside the kidneys themselves

Postrenal AKI

Acute kidney injury caused by a blockage after the kidneys

Uremia

A buildup of waste products in the blood that causes symptoms like nausea, confusion, and itchy skin

Cystitis

Inflammation or infection of the bladder, a type of lower urinary tract infection (UTI)

Urethritis

Inflammation or infection of the urethra

Pyelonephritis

Infection of the kidneys, also known as an upper urinary tract infection

Glomerulonephritis

Inflammation of the glomeruli, usually after a strep infection

Nephrotic Syndrome

A condition where the kidneys leak large amounts of protein into the urine, leading to severe swelling

Urolithiasis

The formation of kidney stones — hard mineral deposits in the urinary tract

Hydronephrosis

Swelling of the kidney due to urine buildup from a blockage

Colicky Pain

Sharp, cramping pain that comes and goes in waves as muscles contract

Benign Prostatic Hypertrophy (BPH)

Non-cancerous enlargement of the prostate gland that squeezes the urethra and blocks urine flow

Urinary Retention

Inability to completely empty the bladder.

Basics of the Urinary System

• The urinary system removes waste, keeps water and electrolytes balanced, and controls blood pressure.

• Kidneys are the main filters — they clean blood, make urine, and help control hormones and blood pressure

Urine flows

Kidney → Ureter → Bladder → Urethra → Out of body

Main organs of the urinary system 

kidneys, ureters, bladder, urethra

Anuria

Almost no urine (<100 mL/day)

Dysuria 

Painful urination

Pyuria 

Pus (white blood cells) in urine, sign of infection

Urinary Tract Infections (UTIs)

Infection anywhere from urethra to kidneys

Lower UTI

Bladder (cystitis) or urethra

Upper UTI

Kidneys (pyelonephritis)

UTIs causes:

• Bacteria (most often E. coli) from bowel entering urinary tract.

• Poor hygiene, not urinating after sex, holding urine too long.

• Catheters or urinary retention increase risk

UTIs signs and symptoms: 

• Dysuria (burning pee), urgency, frequency.

• Cloudy or foul-smelling urine.

• Suprapubic pain (bladder infection)

• Flank pain, fever, chills (kidney infection)

UTIs treatment

• Antibiotics, increase fluids, proper hygiene.

• Cranberry juice can help prevent bacteria from sticking to walls.

Cystitis (Bladder Infection) pathophysiology: 

• Bacteria enter urethra → move into bladder → multiply.

• Causes inflammation of bladder lining

Cystitis (Bladder Infection) signs:

• Dysuria (burning), urgency, frequency.

• Suprapubic pressure or cramping.

• Urine cloudy, foul-smelling urine.

Systemic signs: Usually absent (fever and chills uncommon) 

Cystitis (Bladder Infection) treatment:

• Antibiotics, increased fluid intake.

• Avoid caffeine and alcohol (irritants)

Pyelonephritis (Kidney Infection) pathophysiology: 

• Bacteria travel from bladder up ureters to kidneys.

• Kidneys become inflamed — can cause permanent damage if untreated

Pyelonephritis (Kidney Infection) signs:

• Flank or back pain, fever, chills.

• Nausea, vomiting.

• Costovertebral angle tenderness.

• Cloudy urine, sometimes blood or pus

Systemic signs: present - fever and systemic illness

Pyelonephritis (Kidney Infection) complications:

Chronic kidney damage if repeated infections occur

Pyelonephritis (Kidney Infection) treatment:

• Longer course of antibiotics.

• IV antibiotics for severe cases

Glomerulonephritis

Inflammation of glomeruli (filtering units)

often follows a strep throat infection 

Glomerulonephritis pathophysiology: 

• Antigen–antibody complexes deposit in glomerular capillaries, causing inflammation, increased permeability, and decreased filtration.

• Reduces filtration → wastes build up

Glomerulonephritis signs: 

• Cola-colored urine (blood in urine).

• Proteinuria

• Edema (especially face/eyes in the morning).

• Hypertension

Glomerulonephritis treatment:

• Treat cause (antibiotics if infection).

• Diuretics, antihypertensives.

• Limit fluids, salt, and protein

Nephrotic Syndrome cause

A group of symptoms caused by heavy protein loss from damaged glomeruli, often from chronic disease or immune injury

Nephrotic Syndrome pathophysiology:

• Glomeruli become “leaky” → protein leaks into urine.

• Loss of protein → low albumin → fluid shifts into tissues.

Nephrotic Syndrome signs:

• Massive edema (whole body swelling).

• Proteinuria (very high).

• Frothy/ foamy urine

• Weight gain from fluid 

• Hypoalbuminemia

Nephrotic Syndrome treatment:

• Corticosteroids.

• Diuretics.

• Manage protein and salt in diet

Acute Kidney Injury (AKI)

Sudden loss of kidney function — reversible if treated early

Acute Kidney Injury (AKI) 3 types

• Prenal 

• Intrarenal 

• Postrenal 

Acute Kidney Injury (AKI): Prerenal 

Blood flow problem (e.g., dehydration, shock)

Acute Kidney Injury (AKI): Intrarenal

Damage inside kidney (e.g., glomerulonephritis, toxins,ischemic tubular necrosis)

Acute Kidney Injury (AKI): Postrenal

Blockage (e.g., kidney stones, enlarged prostate).

Acute Kidney Injury (AKI) signs:

• Oliguria or anuria. (rapid drop in urine output)

• Fluid overload (swelling, fluid retention, crackles, hypertension).

• Rising BUN and creatinine

Acute Kidney Injury (AKI) treatment:

• Treat cause (fluids for dehydration, remove blockage).

• Dialysis if severe

• Restore perfusion 

• Support kidney function

Chronic Kidney Disease (CKD)

Slow, progressive kidney damage over months or years

Usually irreversible and often leads to end-stage renal disease

Chronic Kidney Disease (CKD) causes:

Diabetes, hypertension, glomerulonephritis

Chronic Kidney Disease (CKD) pathophysiology:

Nephrons are destroyed → filtration drops → waste builds up

Chronic Kidney Disease (CKD) signs:

• Fatigue, weakness.

• Anemia (low erythropoietin).

• Edema, hypertension.

• Uremia (toxic buildup → confusion, nausea, itchy skin).

• Oliguria/anuria in later stages

Chronic Kidney Disease (CKD) treatment: 

• Control cause (BP, diabetes).

• Dialysis or kidney transplant if advanced.

• Fluid and diet restrictions (low protein, sodium, potassium, phosphorus).

Urinary Tract Obstruction / Kidney Stones (Urolithiasis)

Hard mineral deposits form in urinary tract.

Urinary Tract Obstruction / Kidney Stones (Urolithiasis) risk factors:

• Dehydration.

• High calcium, oxalate, or uric acid.

• Recurrent UTIs

Urinary Tract Obstruction / Kidney Stones (Urolithiasis) signs:

• Sudden, severe flank pain (renal colic).

• Hematuria.

• Nausea/vomiting

Urinary Tract Obstruction / Kidney Stones (Urolithiasis) treatment

• Hydration, pain relief.

• Lithotripsy (break stones).

• Surgery if large

Urinary Tract Obstruction / Kidney Stones (Urolithiasis) prevention

• Drink lots of water.

• Reduce high-oxalate foods (spinach, nuts)

Key feature for Glomerulonephritis 

Inflammatory damage — mostly blood in urine, less protein

Key feature for Nephrotic Syndrome

Protein loss — little or no blood in urine but major swelling

Acute Kidney Injury (AKI) causes:

Low blood flow (prerenal), direct kidney damage (intrarenal), or obstruction (postrenal).

Acute Kidney Injury (AKI) Key feature:

Fast onset, often treatable and reversible

Chronic Kidney Disease (CKD) key feature

Gradual onset, long-term damage, irreversible without transplant

Cystitis (Lower UTI) key feature:

Localized to bladder, mild to moderate symptoms

Pyelonephritis (Upper UTI): key feature 

kidney involvement, more severe, potential for permanent damage

UTI in elderly first sign is often:

confusion

Post-strep + cola urine =

glomerulonephritis

Protein loss + edema =

nephrotic syndrome

Oliguria + rising creatinine =

AKI

Anemia in CKD:

low erythropoietin

Flank pain that radiates + blood in urine

kidney stone