Acute Kidney Injury: Nephrology Notes PDF

Internal Medicine Nephrology Lec. 3 Dr. Nawaf Al-Neaimy 999992 ACUTE KIDNEY INJURY L1 AKI:  a condition where there is a s...

Internal Medicine Nephrology Lec. 3 Dr. Nawaf Al-Neaimy 999992 ACUTE KIDNEY INJURY L1 AKI:  a condition where there is a sudden & often reversible loss of renal function which develops over days to weeks.  It is often accompanied by a fall in UOP Epidemiology :  About 20% of acutely ill patients develop AKI ( esp.elderly) KDIGO ( Kidney Disease Improving Global Outcome ) definition of AKI  AKI is present when any of the following criteria is there : 1. ↑S.Cr. ≥1.5 times baseline level within 7 days 2. ↑S.Cr. by ≥ 0.3 mg/dl over 48 hrs 3. UOP < 0.5 ml/kg/hr for 6 hrs on Aetiology & pathophysiology  There are many causes of AKI and it is frequently multifactorial.  It can be broadly classified into 3 types : 1. Pre-renal ( perfusion to kidneys is ↓) 2. Renal ( Intrinsic kidney disease ) 3. Post-renal ( obstruction to urine flow ) – also termed obstructive uropathy  Pre renal : autoregulation ?  in pre-renal AKI, the kidney is not damaged,therefore GFR can improve rapidly if the renal perfusion is restored.  If not reversed , what is next ? 1  Internal Medicine Nephrology Lec. 3 Dr. Nawaf Al-Neaimy 999992 Clinical presentation p[;\/'.//// ///////////  History ///////////  All acutely ill patients should be assessed for their hemodynamic status , temperature, /////////// RFT , comorbidities & drugs being used. ///////////  If S. Creatinine is raised , it is important to establish whether this is an acute or AKI /////////// /////////// on top of Chronic Kidney Disease ( previous patient’s data might be helpful ) /////////// Symptoms ///////////  AKI can be asymptomatic until exreme loss of renal function occurs ///////////  Oliguria / Anuria is a frequent complaint /////////// ///////////  Uremic symptoms : ///////////  Anorexia /dysguesia/Nausea /Vomiting/wt loss fatigue/muscle cramps/restless /////////// leg/affected mentality /pruritus/bleeding/hiccups/Chest pain. ///////////  Symptoms related to fluid retention : /////////// ///////////  swelling , breathlessness.////////// Signs of AKI /////////// 2 1. Confusion , convulsion , asterixis ( flapping tremor ) , coma { uremic encephalopathy } 2. Pericardial rub { uremic pericarditis } 3. Scratch marks , bleeding manifestations 4. Dyspnea , orthopnea , acidotic ( kaussmal ) breathing , uremic fetor , crackles , pleural rub , pleural effusion. 5. Edema ( dependant &/or orbital and genital ) , raised jvp 6. Hypertension 2  Internal Medicine Nephrology Lec. 3 Dr. Nawaf Al-Neaimy 999992Diagnosis  High RFT ( blood urea , S. Creatinine)  [ previous data showing elevated creatinine For ≥ 3 months suggests Chronicity ] Causes of AKI Pre –renal  Volume depletion ( GI loss , renal loss , hemorrhage , burns )  ↓ Cardiac Output ( HF , ACS , massive PE )  Systemic vasodialation (sepsis , anaphylaxis , cirrhosis )  Intrarenal vasoconstriction ( NSAID, contrast agent , hyperCalcemia , HRS )  Efferent arteriolar Vasodialation ( ACEi , ARB ) Renal ( Intrinsic )  Acute Tubular Necrosis ATN  Acute Interstitial Nephritis AIN  Acute Glomerulonephritis AGN  Acute Vascular syndromes ( MACRO & micro)  Tubular obstruction Acute Tubular Necrosis ATN  Ischemic : prologed pre-renal AKI  Drug-induced : aminoglycosides , amphotericin B , tenofovir , NSAID , contrast agents , immunoglobulins.  Pigments : rhabdomyolysis , intravascular hemolysis Acute Interstitial Nephritis AIN  Drug-induced : penicillins , cephalosporins , sulfonamides , quinolones ,NSAID , PPI , diuretics.  infection : Pyelonephritis , leptospirosis , TB  Autoimmune : SLE , sarcoid , sjögren  Malignancy : leukemia , lymphoma 3  Internal Medicine Nephrology Lec. 3 Dr. Nawaf Al-Neaimy 999992 Acute Glomerulonephritis AGN  Infection related GN ( IRGN)  Rapidly Progressive GN ( RPGN )  Lupus Nephritis ( SLE )  Anti GBM diseasse  Renal Vasculitis Acute Vascular syndromes  Renal artery occlusion  Renal vein thrombosis ( * Nephrotic *)  Cholesterol emboli (* after cath *)  Scleroderma Renal Crisis  Emergency Hypertension  HUS / TTP Thrombotic Microangiopathy (TMA)  HELLP Tubular obstruction  Cast Nephropathy : paraprotien ( myeloma )  Crystal Nephropathy : Tumour Lysis syndrome TLS , acyclovir , ehtylene glycol Post-renal :  Calculi ( stones)  Clot  Retroperitoneal fibrosis  Tumours ( bladder , prostate , cervix )  Urethral stricture  Meatal stenosis 4  Internal Medicine Nephrology Lec. 3 Dr. Nawaf Al-Neaimy 999992 Signs & Investigation results related to the underlying cause p[;\/'.//// /////////// Pre-renal : ///////////  Tachycardia, hypotension ( including orthostatic) , delayed capillary refill , dry /////////// mucous membranes , delayed skin turgor. /////////// ///////////  Labs: ///////////  Urine Na < 20 mmol/l ///////////  FENa < 1% ///////////  High urea : creatinine ratio /////////// ///////////  Bland urinalysis /////////// ATN ///////////  Labs: /////////// ///////////  Urine Na> 40 mmol/l ///////////  FENa ≥ 1% ///////////  Granular ( muddy brown ) cast.////////// GN /////////// 2  HT, edema , rash , arthritis  Labs:  Hematuria , dysmorphic RBCs , RBC cast , protienuria AIN  Fever , rash , arthralgia..(mainly drug-induced)  Labs:  Leucocyturia(pyuria) , WBC cast , eosinophiluria, eosinophilia Post – renal :  flank pain / suprapubic pain , hematuria.  Palpabe kidney /kidneys , distended bladder  Imaging is required :  Obtructive lesion , hydronephrosis/hydroureter , 5 " ‫" ال تنسونا من صالح دعائكم‬