Acute Kidney Injury, Tumours, and Infections - Chapter 30 PDF

Chapter 30 Alterations of Renal and Urinary Tract Function  Urinary Tract Obstruction  Urinary tract obstruction is an interference with the flow of urine at any site along the urinary tract Obstruction can be caused by an anatomical or functional defect...

Chapter 30 Alterations of Renal and Urinary Tract Function  Urinary Tract Obstruction  Urinary tract obstruction is an interference with the flow of urine at any site along the urinary tract Obstruction can be caused by an anatomical or functional defect Obstructive uropathy  Urinary Tract Obstruction (Cont.)  Severity based on: Location Involvement of ureters and kidneys Severity/completeness Duration Cause  Upper Urinary Tract Obstruction  Hydroureter Accumulation of urine in the ureter  Hydronephrosis Enlargement of the renal pelvis and calyces  Ureterohydronephrosis Dilation of both the ureter and the pelvicaliceal system Urinary Tract Obstruction Sites  Upper Urinary Tract Obstruction  Compensatory hypertrophy and hyperfunction Obligatory growth Compensatory growth  Postobstructive diuresis Nephrogenic diabetes insipidus  Upper Urinary Tract Obstruction (Cont.)  Kidney stones Calculi or urinary stones Masses of crystals, protein, or other substances that form within and may obstruct the urinary tract  Upper Urinary Tract Obstruction (Cont.)  Kidney stones (cont.) Risk factors Sex and age Ethnicity Geographical location Seasonal factors Fluid intake Diet Occupation Kidney stones are classified according to the minerals that make up the stone  Kidney Stone Formation  Supersaturation of one or more salts Presence of a salt in a higher concentration than the volume able to dissolve the salt  Precipitation of a salt from liquid to solid state Temperature and pH  Growth into a stone via crystallization or aggregation  Kidney Stone Formation (Cont.)  Other factors affecting stone formation Crystal growth-inhibiting substances Particle retention Matrix  Stones Calcium oxalate or calcium phosphate Struvite Uric acid  Kidney Stones  Manifestation Renal colic  Evaluation Imaging studies 24-hour urinalysis  Kidney Stones (Cont.)  Treatment  Manage pain  Increase fluid intake  Adjust the pH of the urine Decrease dietary intake of stone-forming substances  Stone removal Percutaneous nephrolithotomy Ureteroscopy Ultrasonic or laser lithotripsy  Lower Urinary Tract Obstruction  Neurogenic bladder Dyssynergia Detrusor hyper-reflexia—overactive Detrusor areflexia—underactive Overactive bladder syndrome (OBS) Frequency, urgency, nocturia Obstruction Urethral stricture, prostate enlargement, pelvic organ prolapse Partial obstruction of bladder outlet or urethra  Low bladder wall compliance 1. Which following condition is a risk factor for postobstructive diuresis? A. Dehydration B. Hypertension C. Unilateral obstruction D. Neurogenic diabetes insipidus  Tumours  Renal tumours Renal adenomas Renal cell carcinoma (RCC) Risk factors: Cigarette smoking, obesity, and uncontrolled hypertension  Bladder tumours Renal transitional cell carcinoma (RTCC) Most common Gross, painless hematuria Most common in males older than 60 years  Urinary Tract Infection (UTI)  UTI is inflammation of the urinary epithelium caused by bacteria  Acute cystitis  Painful bladder syndrome/interstitial cystitis  Acute and chronic pyelonephritis Urinary Tract Infection (UTI) (Cont.)  Most common pathogens Escherichia coli  Virulence of uropathogens Host defence mechanisms  Urinary Tract Infection (UTI) (Cont.)  Acute cystitis Cystitis is an inflammation of the bladder Manifestations Frequency Dysuria Urgency Lower abdominal and suprapubic and low back pain  Urinary Tract Infection (UTI) (Cont.)  Acute cystitis (cont.) Treatment Antimicrobial therapy Increased fluid intake Avoidance of bladder irritants Urinary analgesics Urinary Tract Infection (UTI) (Cont.)  Painful bladder syndrome/interstitial cystitis Nonbacterial infectious cystitis; noninfectious Manifestations Most common in individuals with female genitalia who are 20 to 30 years old Bladder fullness, frequency, small urine volume, chronic pelvic pain Treatment No single treatment effective, symptom relief Urinary Tract Infection (UTI) (Cont.)  Pyelonephritis Acute pyelonephritis Acute infection of the ureter, renal pelvis, interstitium  Vesicoureteral reflux, E. coli, Proteus, Pseudomonas Chronic pyelonephritis Persistent or recurring episodes of acute pyelonephritis that lead to scarring Risk of chronic pyelonephritis increases in individuals with renal infections and some type of obstructive pathological condition  Glomerular Disorders  Glomerulonephritis Inflammation of the glomerulus Immunological abnormalities (most common) Ischemia Free radicals Medications or toxins Vascular disorders Infection  Glomerulonephritis  Mechanisms of injury Deposition of circulating soluble antigen–antibody complexes, often with complement fragments (type III hypersensitivity) Antibodies reacting in situ against planted antigens within the glomerulus (type II hypersensitivity– cytotoxic) Nonimmune (ischemia, metabolic disorders, medications, toxins, vascular disorders, infection)  Glomerulonephritis (Cont.)  Manifestations Two major symptoms if severe Hematuria with red blood cell casts Proteinuria exceeding 3 to 5 g/day with albumin (macroalbuminuria) as the major protein Oliguria Hypertension Edema Nephrotic sediment Nephritic sediment  Glomerulonephritis (Cont.)  Types Membranous nephropathy/glomerulonephritis Rapidly progressing glomerulonephritis Antiglomerular basement membrane disease (Goodpasture’s syndrome) Chronic glomerulonephritis  Nephrotic Syndrome  Excretion of 3.5 g or more of protein in the urine per day  Protein excretion is caused by glomerular injury  Findings Hypoproteinemia Proteinuria Edema Dyslipidemia and lipiduria Vitamin D deficiency Hypothyroidism  Nephrotic Syndrome (Cont.)  Membranous glomerulonephritis  Focal segmental glomerulosclerosis  Minimal change nephropathy (lipoid nephrosis)  Nephritic syndrome Hematuria with RBC casts Mild proteinuria Immune injury  Acute Kidney Injury (AKI)  Renal insufficiency  Kidney failure  End-stage kidney disease (ESKD)  Acute Kidney Injury (AKI) (Cont.)  Prerenal Most common cause of AKI Caused by impaired renal blood flow GFR declines because of the decrease in filtration pressure  Acute Kidney Injury (AKI) (Cont.)  Intrarenal Acute tubular necrosis (ATN) is the most common cause Postischemic or nephrotoxic  Postrenal Occurs with urinary tract obstructions that affect the kidneys bilaterally  Oliguria  Acute Kidney Injury (AKI) (Cont.)  Initiation phase Kidney injury is evolving Prevention of injury is possible  Maintenance (oliguric) phase Established kidney injury and dysfunction Urine output is lowest during this phase, and serum creatinine and blood urea nitrogen both increase  Acute Kidney Injury (AKI) (Cont.)  Recovery (polyuric) phase Injury repaired and normal renal function re- established Diuresis common Decline in serum creatinine and urea Increase in creatinine clearance  Acute Kidney Injury (AKI) (Cont.)  COVID-19-Associated Acute Kidney Injury Proteinuria, hematuria, to acute injury requiring renal replacement therapy (RRT) Mechanical ventilation and COVID-associated ARDS increases risk of AKI Careful attention to volume status COVID-19 induces hypercoagulable state potentially causing failure of the exptracorporeal RRT circuit  Chronic Kidney Disease (CKD)  Progressive loss of renal function that affects nearly all organ systems  Associated with HTN, diabetes, systemic lupus erythematosus, intrinsic kidney disease  Stages: Normal (GFR >90 mL/min) Mild (GFR 60 to 89 mL/min) Moderate (GFR 30 to 59 mL/min) Severe (GFR 15 to 29 mL/min) End stage (GFR