Gastro-Nephro Flashcards
What are the signs of shock in acute gastroenteritis?
Tachycardia, weak pulse volume, prolonged CRT >2s, cold peripheries, depressed mental state, with or without hypotension.
What are common viral causes of acute gastroenteritis?
Rotavirus (most common), norovirus.
What are common bacterial causes of acute gastroenteritis?
Campylobacter jejuni, E. coli, Salmonella, Vibrio cholera, Bacillus cereus.
What are common parasitic causes of acute gastroenteritis?
Entamoeba histolytica, Giardia lambdia, Cryptosporidium spp.
What laboratory findings suggest metabolic acidosis in gastroenteritis?
ABG: low pH, low bicarbonate.
How is oral rehydration solution (ORS) administered in gastroenteritis?
20-40 ml/kg over 4 hours, frequent small sips, continue giving extra fluid until diarrhea stops.
What are the complications of acute gastroenteritis?
Secondary lactose intolerance, hemolytic uremic syndrome (HUS), hypovolemic shock, electrolyte imbalance, metabolic acidosis.
Pathophysiology:
Diarrhea & vomiting → excessive fluid loss
Loss of Na⁺, K⁺, Cl⁻, HCO₃⁻ → hypovolemia, hypotension, and shock
Loss of K⁺ → hypokalemia → muscle weakness, arrhythmias
Loss of HCO₃⁻ → metabolic acidosis (from bicarbonate loss in diarrhea)
⏳ Complications:
Hypovolemic shock (low blood pressure, organ failure)
Electrolyte disturbances (arrhythmias, seizures)
Metabolic acidosis (rapid breathing, confusion)
What are the three categories of dehydration severity?
Mild (5%), moderate (5-10%), severe (>10%).
What is the first-line treatment for severe dehydration?
IV normal saline (NS) 10-20 ml/kg over 15-30 minutes.
What are primary causes of nephrotic syndrome?
Idiopathic nephrotic syndrome (most common), membranous nephropathy, membranoproliferative glomerulonephritis, IgA nephropathy.
What are secondary causes of nephrotic syndrome?
SLE, vasculitis (Henoch-Schönlein purpura), poststreptococcal glomerulonephritis, infective endocarditis.
What are the clinical features of nephrotic syndrome?
Edema (periorbital, lower extremities, sacral, scrotal), proteinuria (>50 mg/kg/day), hypoalbuminemia (<3 g/dL), hyperlipidemia.
What is the first-line treatment for idiopathic nephrotic syndrome?
Prednisolone 60 mg/m²/day for 4 weeks, then alternate-day 40 mg/m²/day for 4 weeks, then taper over 4 weeks.
What supportive management is needed for nephrotic syndrome?
Low-salt diet, strict I/O monitoring, ACE inhibitors (Captopril) for hypertension, prophylactic penicillin.
What defines steroid-resistant nephrotic syndrome?
Failure to respond to initial 4-week prednisolone therapy, or two consecutive relapses during tapering or within 14 days after stopping steroids.
What are complications of nephrotic syndrome?
Infection (due to immunosuppression), thromboembolism, growth suppression due to steroids.
What is the most common cause of postinfectious glomerulonephritis?
Group A beta-hemolytic Streptococcus (GAS).
What is the classic triad of poststreptococcal glomerulonephritis (PSGN)?
Hematuria (tea-colored urine), hypertension, edema.
How is PSGN diagnosed?
Evidence of recent GAS infection (ASO titer, positive throat culture), hematuria, proteinuria, reduced C3 levels.
What is the first-line treatment for PSGN?
Supportive care, loop diuretics (furosemide) for hypertension, low-salt diet, antibiotics if infection is still present.
What is the most common cause of urinary tract infections (UTIs)?
Escherichia coli.
What factors predispose to UTIs?
Female sex, vesicoureteral reflux (VUR), urinary stasis, constipation, catheterization.
What is the recommended initial investigation for UTI in children?
Urine dipstick (leukocyte esterase, nitrites), urine microscopy & culture.
What imaging is indicated for recurrent UTIs or structural abnormalities?
Renal ultrasound (RUS), micturating cystourethrogram (MCUG), nuclear renal scan.
What is the first-line treatment for lower UTI (cystitis)?
Oral antibiotics (trimethoprim or nitrofurantoin) for 5 days.
What are the indications for IV antibiotics in UTI?
Infants <3 months, signs of sepsis, upper UTI (pyelonephritis).
What is vesicoureteral reflux (VUR)?
Retrograde flow of urine from the bladder into the ureters.
How is VUR classified?
Grade 1 (reflux into non-dilated ureter) to Grade 5 (gross dilation, loss of papillary impressions).
What is the management of VUR?
Antibiotic prophylaxis, periodic urine cultures, surgical reimplantation in severe cases.
What is the classic triad of hemolytic uremic syndrome (HUS)?
Microangiopathic hemolytic anemia, thrombocytopenia, acute kidney injury (AKI).
What infections are associated with HUS?
E. coli O157:H7, Shigella, Salmonella.
What are the clinical features of HUS?
Bloody diarrhea (prodromal phase), pallor, jaundice, oliguria, neurological symptoms (seizures, confusion).
How is HUS diagnosed?
FBC (hemolytic anemia, schistocytes), stool culture (Shiga toxin), renal function tests.
What is the management of HUS?
Supportive care, dialysis if needed, blood transfusions, plasmapheresis in severe cases.
What are the three types of acute kidney injury (AKI)?
Pre-renal (hypovolemia, sepsis), intrinsic (glomerulonephritis, ATN), post-renal (obstruction).
What are the signs of pre-renal AKI?
Hypotension, tachycardia, dry mucous membranes, oliguria.
What are common causes of intrinsic AKI?
Acute tubular necrosis (ischemia, nephrotoxins), glomerulonephritis, interstitial nephritis.
What are the electrolyte abnormalities in AKI?
Hyperkalemia, metabolic acidosis, hypocalcemia, hyperphosphatemia.
What are the indications for dialysis in AKI?
Severe hyperkalemia, refractory acidosis, uremic symptoms, fluid overload.
What are the causes of generalized edema in children?
Increased hydrostatic pressure (heart failure, nephrotic syndrome), decreased oncotic pressure (hypoalbuminemia), increased capillary permeability (burns, sepsis).
What is the most common cause of intussusception?
Idiopathic, triggered by viral infections (rotavirus, adenovirus).
What is the classic triad of intussusception?
Intermittent abdominal pain, palpable ‘sausage-shaped’ mass, red currant jelly stool.
What is the first-line imaging modality for intussusception?
Ultrasound (target sign, pseudokidney sign).
What is the treatment for intussusception?
Nonoperative reduction (air or saline enema), surgical reduction if unsuccessful.
What is the major complication of untreated intussusception?
Bowel ischemia, perforation, peritonitis.
What is the hallmark sign of acute gastroenteritis on ABG?
Metabolic acidosis.
What is the role of sodium bicarbonate in AKI management?
Corrects metabolic acidosis if pH <7.2 or symptomatic acidosis.
What is the risk of giving excessive IV fluids in dengue or nephrotic syndrome?
Fluid overload leading to pulmonary edema.
