Week 8 Renal Disorders PDF
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This document provides an overview of renal disorders, covering topics such as kidney stone formation, risk factors, and types of stones. The document includes definitions, classifications, and diagrams.
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WEEK 8: RENAL DISORDERS The Renal system Major role in homeostasis → filter 200 L of blood every 24 hours Approx. 1 L of filtered fluid converted → into urine and excreted per day Variety of dis. affect renal function by → inhibiting kidneys’ ability to regulate plasma v...
WEEK 8: RENAL DISORDERS The Renal system Major role in homeostasis → filter 200 L of blood every 24 hours Approx. 1 L of filtered fluid converted → into urine and excreted per day Variety of dis. affect renal function by → inhibiting kidneys’ ability to regulate plasma volume and osmolality Infection of kidneys or urinary tract is most common disorder affecting renal function Stones, tumors, inflammation, or consequences of medical procedures can→ obstruct and/or cause injury to the upper or lower urinary tract Renal system is directly linked to every other organ system Renal injury can affect other organs and become life-threatening! NEPHROLITHIASIS(Kidney Stones/Renal Calculi) Nephrolithiasis: Risk Factors ○ Crystal, protein, or mineral salt form in urinary tract and may cause obstruction Most form in renal calyces (small chambers of the kidney where urine passes), renal pelvis, bladder Unilateral in about 80% of individuals Nephrolithiasis: Risk factors Age Seasonal factors Sex Fluid intake Race Diet Geographic location Occupation Genetic predisposition Kidney stone formation Supersaturation of one or more salts in urine ○ Salt has higher concentration than volume able to dissolve Precipitation of salts from liquid to solid state (crystals) ○ Temperature and PH Kidney stone → Growth via crystallization or agglomeration/to gather into a ball, mass, or cluster. ○ Process → crystals grow from small nidus or nucleus → larger stones ○ Embedded in matrix Substances associated with stone formation ○ Hypercalciuria, Hyperoxaluria, hyperuricosuria, hypocitraturia, crystal growth inhibitor deficiencies ○ Alkaline urine PH → increases the risk of a calcium phosphate stone ○ Acidic urine PH → increases the risk of uric acid stone ○ Hyperparathyroidism and bone demineralization assosc. with prolonged immobilization → known to cause stone formation 4 Substances capable of inhibiting stone formation are (PPMT): Potassium citrate, Tamm-horsfall protein, pyrophosphate, magnesium ○ These reduce risk of calcium phosphate or calcium oxalate precip. in urine ○ Prevent → subsequent stone formation Stones are Classified According to the Primary Minerals (Salts) Composition of mineral salts: ○ Calcium oxalate and calcium phosphate (70% to 80%) ○ Struvite (magnesium, ammonium, phosphate)(1% to 5%) ○ Uric acid(5% to 10%) Genetic disorders of amino acid metabolism: ○ Excess urine can cause → cystinuric, xanthine, stone formation in presence of a low urine pH Definition: - Cystinuria (rare condition) is a stone made from amino acid called cysteine → form in the kidney, ureter, or bladder - Xanthine: a crystalline compound found in blood and urine, an intermediate in the metabolic breakdown of nucleic acids to uric acid. STONES NAMES & PICTURES: a. Calcium Oxalate and Calcium Phosphate: Idiopathic Hypercalciuria b. Calcium Oxalate and Calcium Phosphate: Hyperuricosuria c. Calcium Oxalate and Calcium Phosphate: Hyperoxaluria d. Magnesium-Ammonium-Phosphate (Struvite) e. Uric Acid: Anhydrous f. Uric Acid: Dihydrate ± Uric Acid Anhydrous g. Cystine h. Unknown Classifications PICTURES BELOW: Stones Also Classified According to Location and Size!(location & Size: Staghorn or Non-staghorn) Staghorn calculi Large and fill the minor and major calyces Non-Staghorn calculi Variable size and smaller Located in calyces, renal pelvis, different places along ureter Evaluation and Diagnosis of Kidney Stones Presenting symptoms ○ Renal colic (pain)→ How would one describe renal colic and what other signs and symptoms History ○ Dietary habits ○ Age of first stone episode ○ Stone analysis ○ Presence of complicating factors Focused physical assessment Imaging studies ○ Location of stone, severity of obstruction, associated obstructive uropathy Urinalysis (including pH) 24-hour urine Retrieve and analyze stones Additional tests completed ○ With suspected hyperparathyroidism (elevated serum calcium levels) ○ With cystine calculi, or uric acid (high purine diet) stones Tx of Kidney Stones Managing pain Reducing the concentration of stone forming substances Adjusting the ph of urine Decreasing the amount of stone-forming substances Removing stones using percutaneous nephrolithotomy, , ureteroscopy, or ultrasonic or laser lithotripsy to fragment stones for excretion - Emergency!! → Obstructing kidney stones with suspected proximal UTI are urologic emergencies → requiring emergent decompression, stone removal, and antibiotics! - What health teaching would you provide to your client about how to prevent recurrent kidney stones?__________________________________________________________ PYELONEPHRITIS & GLOMERULONEPHRITIS Acute Pyelonephritis Acute Pyelonephritis: Infection of one or both upper urinary tracts, one or both kidneys may be involved Common Causes Nephrolithiasis, pregnancy, neurogenic bladder, instrumentation, female sex trauma Acute infection of ureter, renal pelvis, and/or kidney interstitium Most common underlying risk factors: Urinary obstruction and reflux of urine from bladder (vesicoureteral reflux) Risk Factors for Acute Pyelonephritis ➔ Premature newborns ➔ Prepubertal children ➔ Sexually active and pregnant women ➔ Women treated with antibiotics that disrupt vaginal flora ➔ Spermicide users ➔ Estrogen-deficient postmenopausal women ➔ Individuals with ◆ Indwelling catheters ◆ Diabetes ◆ Neurogenic bladder ◆ Urinary tract obstruction Acute Pyelonephritis: Pathophysiology E. coli (most common), Proteus, or Pseudomonas Microorganisms also split urea into ammonia→ making an alkaline urine → increases risk of stone formation Infection spread by ascending uropathic microorganisms May also spread through blood Inflammatory process affects kidney pelvis, calyces, medulla ○ Infiltration of leukocytes with renal inflammation, renal edema, purulent urine In severe infections ○ Abscesses may form in medulla and extend to cortex Tubules primarily affected, while glomeruli usually spared ○ After acute phase, healing occurs with fibrosis and atrophy of affected tubules Necrosis of renal papillae can develop Manifestations of Acute Pyelonephritis Onset of symptoms is usually acute: ○ Fever, chills ○ Tachycardia ○ Nausea, vomiting ○ Flank/groin pain ○ UTI symptoms Older adults ○ Early nonspecific symptoms i.e low grade fever ○ Confusion malaise Evaluation and Treatment of Acute Pyelonephritis Evaluation and diagnosis ○ Established by urine culture, urinalysis, clinical manifestations Urine culture assay establishes definitive diagnosis though identification of uropathogen White blood cell casts Treatment ○ Antibiotic administration How do UTIS cause pyelonephritis - Bacteria from gut flora → urinary tract inflammation f the urinary epithelium → retrograde/moving backward of bacteria into urethra bladder → ureter → kidney → can lead to pyelonephritis, inflammation of upper urinary tract PHARMACOTHERAPY FOR ACUTE PYELONEPHRITIS Ciprofloxacin(Antibiotics for Uncomplicated Acute Pyelonephritis): Classification: Fluoroquinolones Drug: Ciprofloxacin Indication: Uncomplicated Acute Pyelonephritis Mechanism of Action: Ciprofloxacin inhibits two bacterial enzymes: DNA gyrase and topoisomerase IV. These enzymes are critical for bacterial DNA synthesis and replication. Desired Effect: Bactericidal action against gram-negative bacteria Adverse Effects: Common: Nausea, vomiting, and diarrhea Serious: Dysrhythmias, liver failure CNS effects: Dizziness, headache, sleep disturbances Antacids, ferrous sulfate, and sucralfate decrease absorption – What is the nursing implication? Trimethoprim-Sulfamethoxazole (TMP-SMX)(Antibiotics for Uncomplicated Acute Pyelonephritis): Classification: Sulfonamides Indication: Uncomplicated Acute Pyelonephritis Mechanism of Action: TMP-SMX is a combination of two drugs, trimethoprim, and sulfamethoxazole They inhibit sequential steps in bacterial folic acid synthesis, essential for bacterial growth and replication Desired Effect: Bactericidal action against gram-negative bacteria Adverse Effects: Common: Nausea, vomiting, rash Serious: Stevens-Johnson syndrome, blood disorders Additional considerations for ciprofloxacin and trimethoprim-sulfamethoxazole Fluoroquinolones (Ciprofloxacin): Well absorbed orally, ideal for outpatient therapy Safety profile: Monitor for dysrhythmias, liver function, and CNS effects Caution in children (potential impact on cartilage development) Avoid use in pregnant or lactating clients First-line drug for post-exposure prophylaxis to Bacillus anthracis (anthrax) Sulfonamides (TMP-SMX): Take with plenty of water to prevent crystalluria Caution in clients with allergies, Stevens-Johnson syndrome risk Avoid in pregnancy and breastfeeding Potential for blood disorders, monitor closely Gentamycin Classification: Aminoglycosides (bactericidal antibiotic) Indication: Severe or Complicated Acute Pyelonephritis Mechanism of Action: It inhibits bacterial protein synthesis and causes the synthesis of abnormal proteins Desired Effect: Treatment of severe infections with aerobic gram-negative bacteria, mycobacteria, and some protozoans Adverse Effects: Ototoxicity: May cause hearing loss and balance disturbances Nephrotoxicity: May cause kidney injury. Neuromuscular blockade: Risk of muscle weakness and apnea Interactions: Risk of nephrotoxicity increases with concurrent use of other nephrotoxic drugs note: Increased risk of ototoxicity with amphotericin B, furosemide, aspirin, cisplatin, and others How would the nurse monitor for adverse effects: ______________________________________________________________________________ Acute Glomerulonephritis Inflammation isolated to kidney glomerulusis caused by primary glomerular injury ○ Infection, immunologic responses, ischemia, free radicals, drugs, toxins, vascular disorders Secondary glomerular injury Glomerular injury occurring as consequence of systemic diseases, including: ○ Diabetes, hypertension, bacterial toxins, systemic lupus erythematosus, congestive heart failure, HIV-related kidney disease Injury to Glomerulus ○ Immune glomerular injury Most common is antigen-antibody complexes depositing in glomerular capillary wall or mesangium Immunoglobulin A (IgA) nephropathy ○ Nonimmune glomerular injury Injury or ischemia from metabolic disorders, toxin exposure, drugs, vascular disorders, infection Immunologic Pathogenesis of Glomerulonephritis Injury begins after antigen-antibody complexes are formed Immune injury caused by activation of inflammatory response! ○ Complement activation, leukocyte recruitment, release of cytokines from leukocytes Complement deposited with the antibodies ○ Complement activation can cause cell injury or attract leukocytes (neutrophils, monocytes, T lymphocytes) through chemotactic stimulus Phagocytes and activated platelets increase inflammatory reaction! ○ Release mediators that injure glomerular filtration membrane including epithelial cells, glomerular basement membrane, and endothelial cells (podocytes and filtration slits) Injury increases glomerular filtration membrane permeability and reduces glomerular membrane surface area Hypertrophy and proliferation of mesangial cells and expansion of extracellular matrix in Bowman space ○ Deposition of these substances and cell proliferation forms a crescent shape within Bowman space ○ Crescent formation is associated with rapidly progressive glomerulonephritis Result of these processes is ○ Compression of glomerular capillaries, decreased glomerular blood flow, hypoxic injury, decreased driving glomerular hydrostatic pressure, alteration in filtration membrane, and decreased GFR Loss of normal negative electrical charge across glomerular filtration membrane and increase in filtration pore size enhance movement of proteins and red blood cells into urine ○ Proteinuria and/or hematuria develop Severity of glomerular damage and decline in glomerular function is related to ○ Size, number, and location of cells injured Focal: affecting some glomeruli Diffuse: affecting glomeruli throughout kidney Duration of exposure Type of antigen-antibody complexes formed Mechanisms of Glomerular Injury: The BIG Picture! Inflammation of glomerulus Antibodies produced against organism that cross-react with glomerular endothelial cells Activation of complement Recruitment and activation of immune cells and mediators Decreased glomerular filtration rate (GFR) Decreased glomerular perfusion (glomerular blood flow) as a result of inflammation ○ Glomerular sclerosis (scarring) ○ Thickening of glomerular basement membrane, but increased permeability to proteins and red blood cells Acute Glomerulonephritis: Manifestations May be silent, mild, moderate, or severe in symptom presentation! Severe or rapidly progressive glomerulonephritis Hematuria with red blood cell casts Smoky, brown-tinged urine Proteinuria exceeding 3–5 g/day with albumin Macroalbuminuria Low serum albumin Edema Oliguria Urine output 30 mL/hour or less Hypertension Renal failure Acute Glomerulonephritis: Evaluation and Diagnosis ○ Urinalysis Proteinuria, red blood cells, white blood cells, casts ○ Reduced GFR Elevated plasma urea, cystatin C, and creatinine concentrations, or reduced renal creatinine clearance ○ Renal biopsy Determines renal injury and location and character of glomerular lesions ○ Electron microscopy Morphologic changes within glomerular capillary wall ○ Staining with fluorescein Identifies complement and different antibodies and associated configurations ○ Microscopy Provides information about distribution and lesions of immune response injury Guides therapy Acute Glomerulonephritis: Management and Treatment Management principles for treating glomerulonephritis related to Treating primary cause Preventing or minimizing immune responses Correcting accompanying problems Edema, hypertension, hypoalbuminemia, hyperlipidemia Specific treatment regimens are necessary for particular types of glomerulonephritis (What would each of these drugs/treatments be used for? WHY would you anticipate that they may be ordered?) Antibiotics Corticosteroids Cytotoxic agents Anticoagulants Diuretics or dialysis PHARMACOTHERAPY FOR ACUTE GLOMERULONEPHRITIS Treatment of Acute Glomerulonephritis: Penicillin Classification: Antibacterial drugs Indication: Treatment of various bacterial infections, including pneumonia, meningitis, skin and soft tissue infections, and certain genitourinary tract infections Mechanism of Action: Disrupting the cell walls of bacteria, leading to their death. Target the penicillin-binding proteins in the bacterial cell wall, weakening it and causing cell lysis Desired Effects Eradication of the bacterial infection causing acute glomerulonephritis Reduction of inflammation and immune response to protect glomerular function Resolution of clinical manifestations and abnormal laboratory findings associated with glomerular disease Adverse Effects Allergic reactions, including anaphylaxis (most common) Diarrhea, nausea, and vomiting Superinfections, including antibiotic-associated pseudomembranous colitis (AAPMC), may develop. In some cases, renal impairment may occur due to the accumulation of penicillins in clients with compromised kidney function Corticosteroids a. glucocorticoid b. Mineralocorticoid Systemic glucocorticoids Wide therapeutic application Short-term use due to potentially serious adverse effects Suppress histamine release and inhibit the synthesis of prostaglandins by COX-2; inhibit the immune system by suppressing certain functions of phagocytes and lymphocytes reduce inflammation Serious adverse effects: suppression of the normal functions of the adrenal gland (adrenal insufficiency), hyperglycemia, mood changes, cataracts, peptic ulcers, electrolyte imbalances, and osteoporosis; mask infections Prednisone Classification: Synthetic glucocorticoid Indications for use: anti-inflammatory (short-term); maintain adrenal function (long-term) Mechanisms of Action: decreased vasodilation and permeability of capillaries, as well as decreased leukocyte migration to sites of inflammation Desired effects: prevent inflammation, reduce risk of bronchospasm in patients with asthma or certain cancers; immunosuppressive at higher dose Adverse effects: Cushing’s syndrome (long-term), fluid retention What are some nursing implications:_______________________________________________________ Renal disorders in children - Incidence and type of renal disorders experienced by children vary with age and maturation - Newborn disorders may involve congenital malformations - During childhood, kidney and genitourinary structures are continuing to develop, so renal dysfunction may be associated with mechanisms and manifestations that are different from those in adults Glomerular Disorders in Children Most common glomerular disorders in children are - Acute post-streptococcal glomerulonephritis - Immunoglobulin A nephropathy - Nephrotic syndrome - Hemolytic uremic syndrome Most glomerular diseases are acquired and immunologically mediated! Acute Poststreptococcal Glomerulonephritis ○ Most common in children ages 5 to 12 years and uncommon in children before age of 3 years Major cause of morbidity with hemolytic Streptococcal infections ○ Occurs after throat or skin infection with certain strains of Streptococcus pyrogenes (hemolytic Streptococcus) Antigen-antibody complexes deposited in glomerulus Immune complexes initiate inflammation and glomerular injury Complex activates complement and release of inflammatory mediators that recruit neutrophils and macrophages and damages endothelial and epithelial cells in glomerular basement membrane Damage to glomerular basement membrane alters membrane permeability and leads to hematuria and proteinuria Acute Poststreptococcal Glomerulonephritis: Manifestations and Treatment Symptoms begin 1 to 2 weeks after an upper respiratory tract infection ○ Pharyngitis, more common during cold weather Symptoms begin up to 6 weeks after a skin infection ○ Impetigo, more common during warm weather Clinical manifestations ○ Sudden onset of hematuria, proteinuria, renal insufficiency, edema, hypertension ○ Oliguria may be present ○ Headache, vomiting, somnolence, other CNS manifestations ○ Dyspnea, tachypnea, and enlarged tender liver Treatment ○ Supportive and symptom-specific ○ Antibiotic therapy ○ Restrict fluid, sodium, potassium intakes ○ Administer antihypertensive drugs ○ Administer diuretics Immunoglobulin A (IgA) Nephropathy Most common form of glomerulonephritis in children Deposition of IgA immune complexes with activation of complement Initiates inflammatory response in mesangium of glomerulus Recurrent microscopic or gross hematuria concurrent with respiratory tract infection (i.e., tonsillitis) or gastroenteritis Most continue to have microscopic hematuria between attacks of gross hematuria and have a mild proteinuria Supportive treatment, dialysis, transplantation Immunoglobulin A Vasculitis: Henoch-Schönlein Purpura Nephritis Rare form of IgA nephropathy But, most common form of systemic vasculitis in children ○ Immune-mediated immunoglobulin A (IgA) vasculitis Causes inflammation and damage to glomerular blood vessels ○ Clinical manifestations Palpable purpura Arthralgia Abdominal pain Renal disease Hematuria and/or proteinuria Treatment ○ Most children recover with supportive care ○ Some progress to end stage renal disease (kidney failure) ○ Severe symptoms require administration of steroids and other immunosuppressant drugs ○ ACEIs Hemolytic Uremic Syndrome Acute disorder characterized by hemolytic anemia, thrombocytopenia, and acute renal failure Considered a thrombotic microangiopathy Most common community-acquired cause of acute kidney injury in children Occurs mostly in those younger than 4 years of age What Causes Hemolytic Uremic Syndrome? Bacterial and viral agents Also endotoxins, i.e. Shiga toxin-producing Escherichia coli (diarrhea associated hemolytic uremic syndrome, D+) Potential sources of exposure include: - Animals, unpasteurized beverages, undercooked meat, and vegetables Genetic forms (nondiarrhea or atypical) are rare - Caused by other microorganisms or by inherited abnormality in complement alternate pathway regulation (i.e., von Willebrand factor–cleaving protease) - Major characteristic is absence of prodromal diarrhea, thus designation D− Hemolytic Uremic Syndrome (D+): Pathophysiology Verotoxin from E. coli absorbed from intestine into blood ○ Binds to white blood cells which are transported to kidney In kidney, white blood cells cause damage to glomerular endothelium ○ With activation of coagulation cascade and aggregation of platelets Glomerular arterioles become swollen and occluded with platelets and fibrin clots ○ Causes decreased glomerular filtration rate with hematuria and proteinuria Swollen and narrowed glomerular vessels damage passing red blood cells and platelets ○ Damaged red blood cells and platelets removed by spleen, causing acute hemolytic anemia and thrombocytopenia Fibrinolysis acts on precipitated fibrin Varying degrees of renal vascular occlusion cause altered renal perfusion and renal insufficiency or failure! Hemolytic Uremic Syndrome: Triad Hemolytic anemia Thrombocytopenia Renal insufficiency Hemolytic Uremic Syndrome: Manifestations Prodromal GI illness ○ Diarrhea with or without vomiting precedes onset by 1 to 2 weeks After symptom-free 1- to 5-day period ○ Sudden onset of pallor, bruising or purpura, irritability, weakness, oliguria Accompanying symptoms ○ Slight fever, anorexia, vomiting, diarrhea (stool characteristically watery and blood stained), abdominal pain, mild jaundice, circulatory overload Seizures and lethargy ○ CNS involvement Severe cases ○ Renal failure within first days of onset Renal failure causes metabolic acidosis, azotemia (accumulated nitrogenous wastes in the blood), hyperkalemia, hypertension Hemolytic Uremic Syndrome: Evaluation Clinical evaluation includes History of preexisting illness Presenting symptoms Urine analysis Blood analysis Hemolytic Uremic Syndrome: Treatment Maintain nutrition Maintain hydration (to dilute toxins) Control hypertension, hyperkalemia, seizures Fluid and electrolyte management Blood transfusions with packed red cells ○ Maintain reasonable hemoglobin levels Dialysis support during acute phase Most children recover completely, but potential long-term sequelae include ○ Renal (hypertension, proteinuria, chronic kidney disease, end stage renal disease) ○ Nonrenal abnormalities (diabetes, neurologic manifestations)