RENAL FAILURE

Acute renal failure(ARF)

 ? Is the clinical syndrome in which sudden decreasing in renal function result in inability of kidney to maintain fluid and electrolyte homeostasis, 2-3% in children, 8% in neonatal ICU.

 ? Causes 

? A-prerenal causes

1- dehydration ? 2- hemorrhage ? 3- hypoalbunimia ? 4- heart failure ?

 B- intrinsic causes , glomeruler diseases 1- post infectious GN ? 2- lupus GN, HSP, ? 3- HUS ? 4- acute tubuler necrosis ? 5- RVT ?

 C- post renal 1- posterior urethral valve ? 2- uretro-pelvic junction obstruction ? 3- stone, neurogenic bladder

 C/F

 ? - vomiting, diarrhea 3 days prerenal ? - 6 years child with recent pharangitis+edema+HT=PSGN ? - critical ill child with protracted HT and HX of exposure to nephrotoxin ATN ? - neonate with hydronephrosis in prenatal U/S congenital P UJ obstruction. ?

 Physical examination 

? - volume status, tachycardia, dry mouth, poor peripheral circulation, prerenal cause ? - peripheral edema, basal creptation, gallop rythem, suggest GN, ATN ? - rash +nephritis=SLE, HSP

 Laboratory finding

 ? anemia due to 1- hemolytic(SLE, RVT, HUS) ? 2- delutional ?

  leucopenia(SLE) ? - thrombocytopenia((SLE, RVT, HUS) ? - hyponatremia(delutional) ? -metabolic acidosis ? -BUN, S.Cre increase ? -uric acid , K+, Ph++, increase ? - CA++ low ? - C3 level low in(SLE, PSGN, radiation GN, membarenoprolefrative) ? - Abs in PSGN ? -GUA 1- RBC, protienurea, granuler cast, internsic cause ? 2- WBC, WBC cast, low grade protienurea, RBC, tubulointerstesial disease

 urinary indices may be useful in differentiation of pre renal and internsic ARF

 ? Intrinsic Indices Pre renal ? Sp.gravity >1.020 <1.010 ? Ur.osmolality >500 <350 ? Ur.NA+(Mag/L) <20 >40 ? FENA+ <1 >2 ? BUN/S.cre >20 <20 ? FENA+=Una X Pcre/P na X Ucre ?

  CXR cardiomegaly, pulmonary edema. ? - Renal U/S hydronephrosis, hydroureter, obstruction ? - Renal biopsy may needed

. Treatment ?

1- infant and children with obstruction or non ambulatory child bladder catheter, to collect UOP ?

 - fluid therapy according to volume status

 ? A- in case of Hypovolemia, N/S 20 CC/kg within 30 min may be repeted 2 or 3 times and watch the UOP in 2 hour , if no possible of internsic or post renal. ? Diuretics indicated provided that good volume status Frusamide 2-4 mg/kg+MANITOL 0.5g/kg , if no UOP within 30 min , consider diuretic infution , if no UOP, consider Dopamin 2-3Mig/kg/min with diuretic , if no UOP, stop diuretic and fluid should be restricted. ?

 B-in case of normal volemia consider(insensible water loss) 400 cc/m2 /day + the fluid equal to the UOP.

 ? C- in case of Hypervolemia insensible water loss and UOP should be omitted. ? Type of the fluid is glucose-containing solution 10-30% as maintaince . ? Input, output, UOP, chemistry sh be checked daily.

 ? 3- Hyperkalemia >6mg/dl may lead to cardiac arrythemia (ECG=tent T wave , widing QRS, ST depression, and arrest). ? Indication of withholding of K+(fluid, diet)+Resin 1g/kg orally or rectally by enema every 2-4 hour. ? If >7mg/dl give the flowing ? 1- Ca.gluconate 10% 1cc/kg within 3-5min ? 2- NACO3 1-2cc/kg over 5-10min ? 3- Reguler insulin 0.1U/kg with glucose 50% 1cc/kg over 1hour. ? If inspite of all these measure , still persistent hyperkalemia consider dialysis

. ? 4- Acidosis if mild rarely need treatment , if sever PH <7.15 NAHCO3 <8 with hyperkalemia need NAHCO3 infusion (desire PH 7.2, NAHCO3 12)

. ? 5- Hypocalcemia primarily treated by lowering S.PH++ , and Ca++ sh be not given I-V unless with tetany to ovoid Ca . deposition in tissue, use Ca. carbonate 1-3 tab with meal

. ? 6- Hyponatremia delutional need fluid restriction , if <120 or symptomatic(seizure, lethargy )need 3%NACL . ? NACL in m.ag required=0.6XBwt X (125- s.NA)

 ? 7- Bleeding due to platelet dysfunction, stress, heparin(dialysis), need oral or I.V H2 blocker ranitidine

 ? 8- HT in GN, HUS, need salt and water restriction, Nefidipine 0,25-0,5mg/kg every 2-6hour(max 10mg), B.blocker,long acting Ca.cannel blocker., if sever crisis need NA nitropruside or Labetalol infusion

. ? 9- Anemia mild, delutional , packed RBC, 10 cc/kg within 4-6hour if Hb <7g/dl(better fresh)

 ? 10- nutrition NA, PH, K, should be restricted in most cases, protein should be moderately decrease, increase calorie intake

. 11- Dialysis indicated in ? a-volume over load +evidence of HT, and /or pulmonary edema refractory to treatment ? b- persistent hyperkalemia ? c- sever acidosis unresponsive to treatment ? d- neurological symptoms(alter mental state , seizure) ? e- BUN >100-150mg/dl or lower if rapidly rising. ? f- Ca/Ph imbalance with hypocalcemia tetany . ? g- inability to provide adequate nutritional intake because of need for sever fluid restriction.

 Chronic kidney disease(CKD)

 ? is defined as either renal injury (proteinuria) and/or a glomerular filtration rate <60 mL/min/1.73 m2 for <3 mo.. ? GFR (ml/min/1.73m²)= K x height(cm)/S.Cre(mg/dl) ? K =0.33 for LBW infant<1year ? K =0.45 for infant <1year ? K =0.55 for child and adolescent female ? K =0.7 for adolescent male ? Mild CRF= GFR 50-75 ml/min/1.73m² ? Moderate GRF= GFR 25-50 ml/min/1.73m² ? Severe GRF= GFR 10-25 ml/min/1.73m² ? End stage renal disease (ESRD)= <10 ml/min/1.73m² - Standardized Terminology for Stages of Chronic Kidney Disease

 ? -STAGE DESCRIPTION GFR (mL/min/1.73 m2) Stage 1 Kidney damage with normal or increased GFR >90 ? Stage 2 Kidney damage with mild decrease in GFR 60–89 ? Stage 3 Moderate decrease in GFR 30–59 ? Stage 4 Severe decrease in GFR 5–29 ? Stage 5 Kidney failure <15 or on dialysis ? End-stage renal disease (ESRD) is an administrative term in the USA, defining all patients treated with dialysis or kidney transplantation. Patients with ESRD are a subset of the patients with Stage 5 CKD

 Etiology ? 1- congenital most common in <5 year of age (renal dysplesia, obstreuctive uropathy) ? 2- acquired various glomeruler disease ? 3- inherited Alpert syndrome , both are more common >than 5year of age ? 4- metabolic cystenosis Pathogenesis

 ? Many factors play role ? 1- hyperfilteration theory ? 2- persistent proteiurea ? 3- systemic arterial renal hypertention ? 4- renal calcium-phosphrous deposition ? 5- hyperlipidemia

 C/F mechanism ? -acidosis 1- impair HCO3 absorption ? 2- ?net acid excretion ? - ? nitrogeniuos products ?? GFR ? - NA+ retention 1- ? rennin ? 2- oliqurea ? - NA+ wasting 1- solute diuresis ? 2- tubuler damage ? - Hyperkalemia 1- ? GFR ? 2- acidosis ? 3- ? K intake ? - Renal osteodystrophy 1- impair renal production of active D3 ? 2- hyper ph++ ? 3- secondary hyperparathyroidism ? 4- inadequate caloric intake -- ? - Growth retardation 1- renal ostiodystrophy ? 2- metabolic acidosis ? 3- anemia, ? 4- growth H resistence ? - Anemia 1- ? erythropioten production ? 2- iron, folate, B12 ?? ? 3- ?? RBC survival ? - Bleeding tendency 1- platelet dysfunction ? - Infection 1- granulocyte dysfunction ? 2- cellular immunity dysfunction ? - Neurological symptoms 1- uremic toxin ? 2- aluminum toxicity ? 3- HT ? - HT 1- volume overload ? 2- excess rennin ? - Pericarditis 1- HT ? 2- fluid over load Lab Finding ? Hyper K+, hypoNA+, acidosis, hypoCA++, hyperph++, hyperurecimia. ? GUA protienurea ? CBC, normochromic normocytic anemia Treatment ? 1- fluid therapy and electrolyte management ? Most patient have normal NA+ and water balance ? Renal dysplesia significant NA+ loss, so we give benefit of higher volume , low caloric density feedung with NA+ supplementation. ? In HT, NA+ resterction, +diuretic therapy ? Hyperkalemia, treated by Resin, alkanizing agent, and no K+ in diet ? 2- Acidosis ? either Bicitra((1 mq NA+ citrate or NA+ Bicorbonate9680 mq equal 8mq base to maintain S.HCO3 22mq/l ? 3- Nutrition ? PH++, K+, NA+, should be restricted according to patient lab finding and fluid balance, Similac formula can be used(low PH++) ? Calorie according to age recommendation ? Protein, should be 2.5g/kg/day , with high biological value(to soluble aminoacid rather than nitrogenious substance)(egg, milk, meat, and fish) ? Water soluble vitamin (Nephrocap), zinc and iron are needed, while fat soluble vitamin is not. ? 4- Growth ? Recombinant human GH, 0,05mg/kg/day s.c to achieve normal height velocity for age with periodic assessment give until ? A- reach 50th centile of midparental HT ? B- final adult HT ? C- undergo renal transplant ? 5- Renal ostiodystrophy ? Indicate spectrum of bone disorder seen in patient with CRF, , high bone turnover with secondary hyperparathyroidism and skeletal pathological finding is a Ostitis Fibrosa Cystica , occur when GFR <50% of normal, ? ?? active D3 ???? in intestinal CA++ absorption?hypoCA++???parath H?? bone resorption ??CA++ level ? When GFR < TO 20-25% of normal , PH++ excretion decrease ?hyperph++ and lead to hypoCA++ and ?parath H ? C/F ? Muscle weakness, bone pain, fracture with minor trauma ? Ricketic chnges ? Lab finding, ?S.Ca,?S.ph, ? AKP, normal or ?parath H ? X.rays widing of metaphyseal space , subperiostial resorption. ? Treatment 1- low ph diet(similac formula) ? 2-Ca.carbonate or acetate (ph. Binder agent), site effect is hypercalcemia, now we use non-ph. Binder agent ? 3- most important is Vit D indicated in ? A- renal ostiodystrophy with PTH >than 3 times its level ? B- persistent hypoCa , inspite of ??S.ph ? Dose is 0.01-0.05Mg/kg/day ? Calciterol (one ?.cap or drop) ? Many nephrologists recommends to maintain Ca/Ph, Ca x Po4 less than 55 to decrease the possibility of Ca.Ph salt deposition. ? 6- Anemia ? Desired Hb level is 11-12 g/dl ? Use of Erythropoietin 50-150mg/kg/dose s.c one to 3 times /week when Hb <10g/dl ? With use of Erythropoietin , give iron oral or i.v ? 7- HT ? Volume over load diuretics ? Excessive rennin ACE inhibitors , Angio II blocker (Lasartan) , effective in lowering of HT ? 8-Immunization ? MMR, Varecella , should be given before transplantation ? Influenza vaccine should be given annually. ? Flow up ? Hb, S.electrolyte, BUN, S.Cre, Ca, Ph, AKP, , PTH, X.rays of bo