11. Urinary System Pathologies Flashcards
Urinary Tract Infections (UTIs)
- Infection & inflammation of the urinary tract. UTI’s can affect any part of the urinary tract.
- More common in women.
- Increases with age.
- Microbial infection (often bacterial)
Urinary Tract Infections (UTIs): Signs and Symptoms
- Dysuria, frequent urination, nocturia, cloudy & smelly urine, suprapubic pain.
- Haematuria, nausea, confusion.
Urinary Tract Infections (UTIs): Diagnosis
•Urine dipsticks: Nitrates, leukocytes and erythrocytes
Cystitis
- Infection of the bladder(a type of UTI).
- Can be divided into acute and chronic causes.
- More common in women(urethra shorter and closer to anus).
- 75%+ of cystitis caused by E.coli(bacteria from the intestinal flora).
Cystitis: Causes
- Bacteria being pushed into urethra: ‘Honeymoon cystitis’, wiping back to front, catheterisation.
- Post-menopausal (thinned lining) & Diabetes mellitus.
- Chronic cystitis is common in older men with an enlarged prostate. It obstructs urine flow causing bladder urine stasis.
Cystitis: Signs and Symptoms
- Pain in lower back/abdomen.
- Dysuria& frequent/urgent need to urinate but only passing small amounts (oliguria).
- Dark, smelly/cloudy urine.
- Systemic signs -malaise, nausea, fever.
Cystitis: Diagnosis
- Dipstick: Nitrates, leucocytes & erythrocytes.
* Urine microscopy: Significant Bacteriuria.
Cystitis: Allopathic Treatment
Antibiotics
Pyelonephritis: Kidney infection
- A microbial infection of the renal pelvis & medulla.
- Often a result of ascending bacterialspread from bladder (i.e. E.coli) or (more rarely) through the blood.
- Renal pelvis & calyces fill with purulent exudate.
- Repeated episodes of ‘acute pyelonephritis’ are common and can lead to ‘chronic pyelonephritis’.
- Chronic pyelonephritis can lead to destruction (necrosis) and scarring of renal tissue.
Pyelonephritis: Causes
- Infection spreading up from the bladder.
- Diabetes Mellitus.
- Immunocompromised patients.
- Obstructed flow of urine (enlarged prostate, kidney stones).
- Pregnancy.
- Gout.
Pyelonephritis: Signs and Symptoms
- Loin pain and tenderness (often unilateral).
- Dysuriaand increased frequent urgency.
- Haematuria & cloudy/foul smelling urine.
- Fever, nausea, vomiting, malaise, fatigue.
Pyelonephritis: Diagnosis
- Dipstick urinalysis: Nitrates, erythrocytes, leukocytes, protein.
- Urine microscopy: Bacteria, urinary casts (of blood or epithelial cells), blood cells and protein.
- Blood: ↑Inflammatory markers (ESR) & WBCs.
- Imaging: Ultrasound.
Pyelonephritis: Complications
- Septicaemiaand renal abscess.
- Secondary hypertension.
- Chronic pyelonephritiscan lead to chronic kidney disease and renal failure.
Pyelonephritis: Allopathic Treatment
- Strict bed rest, fluids (>2L), warm packs.
* Antibiotics (broad spectrum).
Glomerulonephritis
• An immune mediated disease that causes glomerular inflammation.
Glomerulonephritis: Pathophysiology
- Autoimmune reaction (type III hypersensitivity) -whereby antigen–antibody immune complexes are formed in response to infection.
- These immune complexes are deposited in the glomeruli where they trigger an immune response, which leads to leaky capillaries & leukocyte proliferation, allowing proteins and erythrocytesto escape into urine.
Glomerulonephritis: Causes
• Divided into Primary (when no associated disease
elsewhere) or Secondary (when glomerular
involvement is part of a systemic disease e.g. SLE).
• Autoimmune: Immune-mediated injury to the
glomeruli. Often occurs 1-3 weeks after a bacterial
infection (often from upper respiratory tract).
• In children, post-streptococcal glomerulonephritis is
common.
Glomerulonephritis: Clinical Presentation
- Asymptomatic haematuria and/or proteinuria causing cloudy/frothy urine.
- Back pain due to glomerular inflammation.
- Fluid retention: peripheral & facial oedema.
- Oliguria.
- Hypertension (Due to ‘Glomerulosclerosis’: Scarring & fibrosis of glomerular capillaries reduces renal blood flow & GFR resulting in an increase in renin).
- Fatigue, headaches, fever, nausea.
Glomerulonephritis: Diagnosis
- Urinalysis: Erythrocytes & protein.
* Blood: Elevated ESR & CRP, GFR (low), serum albumin low. Elevated serum urea, creatinine, antibodies.
Glomerulonephritis: Treatment
Corticosteroids
Antibiotics
Diuretics
Nephrotic Syndrome
• A collection of signs and symptoms associated
with increased glomerular permeability (leaky)
and heavy proteinuria.
• Characterised by proteinuria & hypoalbuminaemia.
• The loss of plasma proteins leads to low plasma
osmotic pressure, so fluid moves out of capillaries
into tissues = oedema.
Nephrotic Syndrome: Causes
- Glomerulonephritis & Diabetic glomerulosclerosis.
- Systemic Lupus Erythematosus.
- Infections (HIV, malaria, hepatitis etc.)
- Drugs (NSAIDs).
Diabetic Kidney (Nephropathy)
• 40% of diabetics develop diabetic nephropathy.
• Renal failure is the cause of death in 10% of diabetics.
• Pathogenesis:
Diabetes mellitus elevates blood pressure. Glomerulosclerosisoccurs as a result of the increased intra-glomerular pressure. The kidneys are often enlarged (different to other pathologies).
•Glomeruli become damaged and proteins leak (microalbuminuria) -> nephrotic syndrome.
Diabetic Kidney: Signs and Symptoms
Initially none Fatigue Nausea Vomiting Pallor Oedema
Renal calculi: Kidney Stones
- Most commonly made of calcium oxalate and phosphate (80%). Other types include uric acid stones and magnesium stones.
- 2% of the population have kidney stones.
- Men more commonly affected (3:1).
- Stones may stay in position (can obstruct urine outflow) or migratedown the urinary tract, producing symptoms on route.
Kidney Stones: Causes
Dehydration(increased solute concentration)
Hypercalcaemia (e.g. hyperparathyroidism)
Gout (hyperuricaemia)
Renal anatomical anomalies
Kidney Stones: Signs and Symptoms
- Often asymptomatic.
- Severe loin pain, radiating to the groin (‘ureteric colic’).
- Trace of blood in the urine(on dipstick test).
- Nausea, vomiting and fever.
Kidney Stones: Treatment
- NSAIDs. Drink lots of fluids, shockwave therapy or surgery.(>6mm only 1% can pass).
- Avoid intake of oxalate rich food e.g. Rhubarb, spinach, cocoa. Avoid calcium.
Diuretics
• Medications which Increase loss of sodium and water from the kidneys.
• Diuretics reduce water and sodium re-absorption from the kidney tubules.
• Used for oedema and hypertension.
• Three groups:
Thiazide diuretics (act on DCT)
Loop diuretics (act on loop of Henle)
Potassium sparing diuretics (act on collecting ducts).
• Diuretics cause excessive excretion of potassium, sodium, chloride & magnesium.
• It is essential to replace lost electrolytes. Foods such as celery act as a diuretic.
Renal Dialysis
- Renal dialysis is also known as “renal replacement therapy”.
- Used for patient in renal failure, whereby it mimics excretory function of kidneys to remove wastes/balance electrolytes etc.
- Two types: Haemodialysis& Peritoneal Dialysis.
- Both carry increased risk of infection, so often given antibiotics (consider side effects).
Peritoneal Dialysis
- Peritoneal dialysis utilises the peritoneum’s structure as a highly vascular semi-permeable membrane, to allow for diffusion of fluids & dissolved substances.
- A tube is inserted into the abdomen which administers dialysis fluid, through which waste products diffuse into. Removal occurs via a shunt.
- Often administered at home. Takes longer than haemodialysis but is often more comfortable.
- Excess water can be removed by changing dialysis solution.
- Significant risk of peritonitis at site of tube exit.
Haemodialysis
- Removing waste products (e.g. urea, creatinine) and water from blood.
- Usually in hospital but can be outpatient. Usually require 3 times a week, 3-4 hours each.
- Anticoagulants are used to prevent blood clotting.
- Side effects include hypotension (removal of too much fluid).
