Nephrology Flashcards
Define Stage 1, 2 and 3 AKI per 2022 KDIGO staging.
Stage I: Cr 1.5-1.9x baseline in 7 d OR increase >/=0.3mg/dl in 48hr, U/O <0.5ml/kg/h for 6-12hr
Stage II: Cr 2-2.9xbaseline, <0.5ml/kgh for >/=12hrs
Stage III: Cr >/=3x baseline or >4mg/dl or initiation of RRT or eGFR<35ml/min/1.73m2, U/O <0.3 for >/=24hr or anuria for >/=12hrs
DDx for pre-renal AKI?
GI losses, hemorrhage, decreased cardiac output, decreased vascular resistance (sepsis), nephrotic syndrome, liver failure, impaired renal autoregulation (hyperCa+, ACEi, NSAIDs, tacrolimus, cyclosporine)
DDx for renal AKI?
Tubules/interstitium: ischemic tubular injury, nephrotoxic AKI, acute interstitial nephritis
Glomerulus: PIGN, HUS
Blood vessels: renal vein thrombosis
DDx for post-renal AKI?
UPJ obstruction, ureteric obstruction, bladder obstruction, urethral obstruction
*Both kidneys need to be obstructed!
Name 5 medications known to be nephrotoxic.
Acyclovir, AmphoB, Captopril, Cisplatin, Cyclosporine, Enalapril, Gentamicin, Ibuprofen, Ketorolac, Lisinopril, Tacrolimus, Tobramycin, Vancomycin
Name the ECG changes associated with hyperkalemia
Tall peaked T waves, flattened/absent P waves, sine wave, prolonged PR, widened QRS, bradycardia/Vtach/VFib
What are the indications for dialysis?
AEIOU
A: acidosis
E: electrolyte abnormalities (hyperK, hyperNa, hyperPO4)
I: ingestions (methanol, ethylene glycol, ASA, lithium)
O: fluid overload
U: symptoms of uremia (pericarditis, encephalopathy, seizures, bleeding)
What is the criteria for CKD?
Either of the following present for >3 months:
Markers of kidney damage (1 or more): albuminuria, ACR >30mg/g or 3mg/mmol, urine sediment abN, abN ‘lytes due to tubular d/o, abN histology, structural anomaly, hx transplant
Decreased GFR: < 60ml/min per 1.73M2
What is the most common cause of childhood CKD?
Renal dysplasia: hypodysplasia, solitary kidney, VUR, posterior urethral valves
- Dx on U/S: sm kidneys, echogenic parenchyma, cortical cysts
2nd most common: glomerulopathy
3rd most common: cystic kidney disease
What is oligohydramnios sequence (Potter’s phenotype)?
Deep set eyes, beaked nose, micrognathia, low set ears, extremity contractures, pulmonary hypoplasia (about 1/2 die soon after birth of pulmonary insuff)
What are the features of a distal RTA (Type 1)?
Impaired hydrogen ion excretion Urine pH >5.5 HypoK Renal stones, hypercalciuria ALL RTAs = hyperchloremic metabolic acidosis w/ normal serum AG
What are the features of a proximal RTA (Type 2)?
Impaired bicarbonate reabsorption
High urine pH initially, later <5.5
HypoK
ALL RTAs = hyperchloremic metabolic acidosis w/ normal serum AG
What are the features of a Type IV RTA?
Decreased aldosterone secretion or aldosterone resistance
Urine pH <5.5
HyperK
ALL RTAs = hyperchloremic metabolic acidosis w/ normal serum AG
What findings do you expect in SIADH for the following parameters:
- Serum Na
- Urine Na
- Serum osm
- Urine osm
- HypoNa
- Urine Na >20meq/L
- Low serum osm
- Elevated urine osm (>100)
- Fun fact: uric acid does the same as sodium; SIADH will have low serum uric acid and high urine excretion of uric acid
What is the most common pathogen associated with infection in patients with nephrotic syndrome?
S. pneumoniae (patients with nephrotic syndrome are at risk for SBP)
What is the in utero US measurement which defines severe antenatal hydronephrosis?
Renal pelvis diameter >10mm in second trimester or >15mm in third trimester is defined as severe ANH
-Earlier fetal age at diagnosis protends a more severe condition
What is in the differential diagnosis of antenatal hydronephrosis?
- Transient/physiologic (50-70%)
- Ureteropelvic junction obstruction (10-30%)
- Vesicoureteral reflux (10-20%)
- Megaureter/ureterovesical junction obstruction (5-15%)
- Multicystic dysplastic kidney (5%)
- Posterior urethral valves (1-2%)
How many mmol of Na is found in 1000mL of NS solution?
154 mmol
What is the most common cause for hypoalbuminemia in children?
Renal disorder - need to check urinary protein!
Nephrotic syndrome with a low C3 and a normal C4. What is the most likely cause?
PSGN/PIGN
Nephrotic syndrome with a low C3 AND low C4. What is the most likely cause/DDx?
- Lupus nephritis
- Membranoproliferative GN
- Chronic bacteremia (endocarditis, shunt nephritis)
Nephrotic syndrome with normal complements (C3 and C4). What is most likely cause/DDx?
- IgA nephropathy
- Alport syndrome
- Henoch-Schonlein purpura nephritis
- ANCA vasculitis
- Granulomatosis with polyangitis
- Microscopic polyangitis
What syndrome is defined by the following triad?
- Abdominal muscle deficiency
- Severe urinary tract abnormalities
- B/L cryptorchidism in males
Prune Belly Syndrome
-Most have VUR
What is the recommended fluid volume for oral rehydration solution in moderate dehydration?
100ml/kg plus replacement of continuing losses over 4 hours
-50mL/kg for mild
(from retired CPS statement)
What vaccine do you recommend for children with nephrotic syndrome considering their increased risk of infection?
Pneumococcal 23/PCV 23
Other vaccine recommendations:
-PCV 13 (4 doses given in routine schedule <15mo)
-Annual flu vaccine
-Defer live vaccines until 1 month after D/C of high dose steroids (CPS)
-Live vaccines C/I in children on cyclosporine or cyclophosphamide
-Give VZV Ig after close contact with varicella infection, immunize healthy family members
What is the treatment for a torsion of the appendix testis?
-Analgesics, bed rest and scrotal support
What is the most common renal stone in children?
Calcium
-Calcium oxalate > calcium phosphate
What is the triad of hemolytic uremic syndrome?
- Microangiopathic hemolytic anemia
- Thrombocytopenia
- Renal insufficiency
What is the most common cause of renal mass in newborns?
Hydronephrosis
What is the most common cause of nephrotic syndrome?
Minimal change disease
