patho370 Study Guide Week 6 Ch. 27,28, 29, 31 & 33

Overview of Urinary System Functions: Waste management

excreting toxins, waste stuff, and excess electrolytes

Overview of Urinary System Functions: Acid/Base balance

   2 organs in the body doing it: kidneys & lungs

Overview of Urinary System Functions: Fluid balance

   well-balanced overall body, total fluid

o  If too much excretion of water → dehydration

o  If too little excretion → edema

If something is wrong with the Glomerulus →

 Filtration issue

If something is wrong with the Renal tubular system →

absorption, excretion issue

Uremic Syndrome

HIGH waste (H+, Cr, UREA) + Hemolysis (LOW RBC life span) + LOW WBC + Skin disorders (Dermatitis, Uremic Frost)

Filtration

Filters waste materials → how much? = serum creatinine, rate (GFR)

Filtration: Urine

urine → urine output = 1% of total filtration (800-2000ml)

• < 400-800 ml → Oliguria

• > 2000 ml → Polyuria

FOR HEALTHY PEOPLE:

UO measured in REAL TIME → 24 HRS COLLECTION

FOR ADMITTED PATIENTS:

UO measured in PREDICTION WAY → usually measured in a 3-4 hrs time window ( F.ex: for 3 hrs = 60ml → for 24 hrs =480 ml)

Why prediction on patients? we want to evaluate the patient’s kidney status → RIFLE

Intrarenal Disorders:

-       Congenital

-       Neoplastic

-       Infectious

-       Obstructive

-       Glomerular

Congenital: Agenesis

no development in the fetus

o  Unilateral agenesis compensatory hypertrophy of functional kidney

o  Bilaterial agenesis NOT compatible with life

Congenital: Hypoplasia

  some fetal kidney development

o  Can lead to pediatric end-stage renal failure

o  A single normal kidney can maintain normal renal function

Cystic Kidney Diseases:

Mutation of 2 genes → resulting in fluid-filled cysts → LOW urine formation and flow

Autosomal recessive forms:

   in kids

Autosomal dominant types:

in adults

Cystic Kidney Diseases: Pathogenesis

massive cysts formations in kidneys → put pressure on nephron function

-       LOW GFR → LOW urine output → oliguria

-       LOW GFR → LOW urine sodium (U-Na) → HIGH RAAS → HIGH BP → hypertension

-       Cysts can invade intra-renal capillary → hematuria

→ 3-H

Renal Cell Carcinoma:

p53 mutation, smoking, obesity, and hypertension are some risk factors

Renal Cell Carcinoma: Pathogenesis

tumor puts pressure on nephron function →

-       LOW GFR → LOW urine output → oliguria

-       LOW GFR → LOW urine sodium (U-Na) → HIGH RAAS → HIGH BP → hypertension

-       Tumors invade intra-renal capillary → hematuria

-       Palpable mass

-       Staging system: I-IV

Nephroblastoma (Wilms Tumor)

Kidney cancer in children

-       Hypertension

-       Palpable abdominal mass → abdominal palpitation

-       Hematuria

UTI:

bacterial infection either in the bladder or urethra → asymptomatic or polyuria/dysuria

-       Most common bacteria is E-Coli

Pyelonephritis:

infection of renal pelvis/ parenchyma,

-       CVA tenderness (classic sign)

-       Fever, chills, N/V

Pyelonephritis: Treatment

antibiotics

Obstruction:

conditions that interfere with the flow of urine → Urine stasis →

-       Infection

-       Structural damage

-       Kidney stones

Stones:

Calcium oxalate, Uric acid, Struvite, Cystine

-       Most common stones: Calcium oxalate

Tumors:

Tumors from urinary & abdominal organs

-       Internal

-       External (from other organs)

Prostatic hypertrophy:

BPH/ Prostate cancer

Sequala of Obstruction: Complete obstruction results in

-       Hydronephrosis

-       Decreased GFR

-       Infection

-       Ischemic kidney damage because of increased intraluminal pressure → ATN

Acute Kidney Injury (AKI):

-       Prerenal

-       Postrenal

-       Intrinsic/ Intrarenal

Prerenal:

dimmish perfusion of the kidney, MOST COMMON TYPE

If < 6 hrs → NO NEPHRON DAMAGE

If > 12 hrs → NEPHRONE DAMAGE —> INTRARENAL INJURY

-       Heart failure

-       Hypovolemia

-       Vomiting, diarrhea

-       Burns

-       Drugs

-       Stenosis of renal artery

Postrenal Kidney Injury:

Obstruction within the urinary collecting system

If < 6 hrs → NO NEPHRON DAMAGE

If > 12 hrs → NEPHRON DAMAGE → INTRARENAL INJURY

-       Kidney stones

-       Tumor

-       BPH

Intrinsic/ Intrarenal Kidney Injury:

dysfunction of the nephrons

• Vascular

• Glomerular

• Interstitial

20%

o  Drugs (NSAID, Antibiotics)

o  Infections

-       Tubular (80%) → ATN

-       Ischemia (80%)

-       Nephrotoxic (contrast)

Creatinine in the urine = Creatinine Clearence

Sequala of AKI:

-       LOW glomerular filtration rate (GFR) → LOW urine output

-       Volume overload

-       HIGH serum creatine

-       Retention of nitrogenous waste products effects (BUN) → azotemia/ uremia

o  Severe case: uremic syndrome

Clinical Presentation of Acute Tubular Necrosis:

Chronic Kidney Disease: Progressive/ irreversible loss of nephrons

-       Decreased kidney function or kidney damage of 3 months’ duration based on blood tests, urinalysis, and imaging studies

-       GFR < 60ml/minute/1.73 m2 for three months with or without indication of damage to the kidney

Chronic Kidney Disease: Risk Factors

-       Diabetes

-       Hypertension

-       Recurrent pyelonephritis

-       Glomerulonephritis

-       Polycystic kidney disease

Progressive process (irreversible)

Chronic kidney disease (CKD) → Chronic renal failure (CFR) → end-stage renal disease (ESRD → dialysis

Hypertension and Cardiovascular disease

o  Hypervolemia

o  Increased RAAS and SNS activity

Uremic Syndrome

o  Retention of metabolic wastes

o  Pruritus/ Dermatitis/ Uremic frost

Metabolic acidosis

o  Retention of acidic waste products

o  Hyperkalemia

Electrolyte imbalances

o  Retention of electrolytes potassium, phosphorus, magnesium

Bone and mineral disorders

o  LOW produce active Vit D, Hyperkalemia

o  Elevated phosphorus and PTH causes altered bone/ mineral

Anemia

o  Lack of erythropoietin/ EPO

o  Uremia shortens RBC life

Disorders of the Bladder

-       Role is to transport urine formed by the kidneys and allow removal from the body

-       Urine movement due to the effect of gravity and facilitated by peristatic movement of the ureters

Disorders of the Bladder: Diagnosis

-       Urinalysis: for diagnosis of infection

-       Ultrasonography: visualization of the urinary system

-       Urodynamic testing: used for diagnosing voiding dysfunctions

Mechanics of Micturition Bladder innervation is supplied by

-       Sympathetic nerves: allow relaxation and filling of bladder and contraction of internal urethral sphincter

-       Parasympathetic nerves: contraction of the bladder relaxation of internal urethral sphincter

-       Stomatic pudendal nerve: innervates the external bladder sphincter

Stress Incontinence:

involuntary leakage of urine during activities that increase intra-abdominal pressure, such as coughing, sneezing, laughing or physical exercise

Stress Incontinence: Etiology

weakening of the pelvic floor muscles and the urethral sphincter

-       Commonly seen in women after childbirth, menopause

Urge Incontinence (Overactive Bladder):

Sudden and intense urge to urinate followed by involuntary loss of urine

Urge Incontinence (Overactive Bladder): Etiology

-       Overactivity of the detrusor muscle

o  Conditions take urinary tract infections, neurological disorders (e.g. Parkinson’s disease, multiple sclerosis)

Overflow Incontinence

Continuous dribbling of urine or feeling of incomplete bladder emptying

Overflow Incontinence: Etiology

Obstruction of the bladder outlet (e.g. enlarged prostate, urethral stricture) or weak bladder contractions (e.g. diabetic neuropathy, spinal cord injury) bladder becomes overly full. Causing urine to overflow

Mixed Incontinence:

Combination of stress and urge incontinence  symptoms of both types are present

Bladder Cancer:

Fourth most common in males, eighth most common in females

Bladder Cancer: Risk Factors

-       Age

-       Smoking

-       Carcinogenic chemicals

Bladder Cancer: Pathogenesis

Most tumors originate from the transitional epithelium (urothelium)

Bladder Cancer: Clinical manifestations

-       Hematuria

-       Frequency and urgency

Bladder Cancer: Treatment

-       Surgery, radiation therapy, chemotherapy, wand immunotherapy

Disorders affecting:

-       Penis and male urethra

-       Scrotum and testes

-       Prostate

Categories Disorders of the Penis & Male Urethra:

-       Congenital

-       Acquired

-       Infectious

-       Neoplastic

Disorders of the Penis & Male Urethra: Congenital Disorders

Acquired Disorders: Priapism

Painful, persistent erection

Acquired Disorders Priapism: Etiology

Sickle cell disease, leukemia, medications

Acquired Disorders Priapism: Treatment

Aspiration, a-adrenergic agents. Surgery

Phimosis vs Paraphimosis:

Erectile Dysfunction (ED): Primary

-       Never achieved erection

-       Often psychological

Erectile Dysfunction (ED): Secondary

-       Previously normal erections

Erectile Dysfunction (ED): Etiology

-       Vascular disease

-       Diabetes

-       Endocrine disorders (pituitary dysfunction (LOW luteinizing hormone, LOW testosterone)

-       Medications (antihypertensives, antihistamines, some antidepressants)

-       Surgery

Erectile Dysfunction (ED): Treatment

Determines psychogenic or organic cause

-       PDE-5 inhibitors (Viagra, Cialis)

-       Injections of Vasoactive medications: papaverine, phentolamine, prostaglandin E

-       Penile prosthesis

Disorders of the Scrotum and Testes: Cryptorchidism

Undescended testes

-       HIGH risk of infertility and cancer

Disorders of the Scrotum and Testes Cryptorchidism: Treatment

Orchiopexy, Human chorionic gonadotropin (hCG)

Hydrocele vs Spermatocele:

Testicular Torsion:

-       Twisting of spermatic cord → compromised vascular supply and ischemia

-       Medical emergency

Testicular Torsion: Clinical Manifestation

-       Sudden severe pain

-       Swelling, nausea

Testicular Torsion: Treatment

-       Emergency surgery

-       Salvage possible within 12 hours

Infectious Disorders: Epididymitis

Inflammation from infection or urine reflux

Infectious Disorders Epididymitis: Clinical Manifestation

-       Fever, urethral discharge

-       Enlarged, reddened, tender scrotum

-       Scrotal pain with radiation into inguinal area

Infectious Disorders Epididymitis: Treatment

-       Treat with antibiotics, bed rest

Sexually Transmitted Infections:

Neoplastic Disorders: Testicular Cancer                                               

-       Most common solid tumor in 20-34

Strongly associated with cryptorchidism