Renal and Urinary Tract Congenital and ARF PATHOMA/FA Flashcards
In UNILATERAL AGENESIS of kidney, what happens to the existing kidney? Is there any consequence of it?
HYPERTROPHY - Existing kidney does work of both
Consequence: Increased risk of RENAL FAILURE later in life with HYPERFILTRATION injury
In BILATERAL AGENESIS of the kidney, what are the 3 possible consequences that make up the POTTER SEQUENCE? What is the underlying cause?
UNDERLYING CAUSE: Oligohydramnios (low Amniotic fluid - kidney filtrate that the baby floats around in)
POTTER SEQUENCE = Lung hypoplasia + Flat face/Low set ears + Extremity dvlm defect
What are the 3 congenital malformations that result in cyst formation?
- DYSPLASTIC KIDNEY
- POLYCYSTIC KIDNEY DISEASE
- MEDULLARY CYSTIC KIDNEY DISEASE
Is DYSPLASTIC KIDNEY an INHERITED congenital malformation? Where do the cysts form, what is a main component of the cysts?
NO, NOT INHERITED - Low risk of having dysplastic kidney in subsequent pregnancy
CYSTS in the RENAL PARENCHYMA - Made of abnormal tissue (particularly cartilage)
Is POLYCYSTIC KIDNEY an INHERITED congenital malformation? Do cysts form unilaterally or bilaterally? Where are the cysts formed?
YES, INHERITED
BILATERAL enlarged kidney with Cysts in the RENAL CORTEX + MEDULLA
What are the 2 subtypes of POLYCYSTIC KIDNEY? What age population is most commonly affected by each?
- Autosomal recessive - JUVENILE form affecting INFANTS
2. Autosomal dominant - AD form affecting ADults
What are the clinical Sx of AUTOSOMAL RECESSIVE POLYCYSTIC KIDNEY DISEASE?
- Worsening renal failure
2. HTN
What is a particularly important and dangerous complication that can occur in severe AUTOSOMAL RECESSIVE PKD?
POTTER SEQUENCE - AR PKD being so severe that it can manifest as bilateral agenesis (no kidney at all) -> Oligohydramnios -> Potter Sequence
What are the 2 common associations of AUTOSOMAL RECESSIVE PKD?
‘Cysts in the kidney, cysts in the liver’
Kidney Cysts + Hepatic Cyts + Hepatic fibrosis (resulting in PORTAL HTN)
What are the clinical Sx of AUTOSOMAL DOMINANT PKD?
- Worsening Renal Failure
- HTN
- Hematuria
What is the likely pathogenesis of AUTOSOMAL DOMINANT PKD?
Mutation in APKD1 or APKD2 gene
What are the 3 common associations of AUTOSOMAL DOMINANT PKD?
‘Cysts in the kidney, cysts in the liver, cysts in the brain’
Kidney Cysts + Hepatic Cysts + Cystic Dilatation (berry aneurysm) + Mitral valve prolapse
24yo pt has family history of renal disease and multiple deaths in the family due to renal conditions or a brain hemorrhage. What is on the #1 differential’s condition?
AUTOSOMAL DOMINANT POLYCYSTIC KIDNEY DISEASE
What are the 2 main differences between MEDULLARY CYSTIC KIDNEY DISEASE (MCKD) and POLYCYSTIC KIDNEY DISEASE (PKD)?
MCKD - Cysts form in the MEDULLARY COLLECTING DUCTS + Kidneys are SHRUNKEN
PCKD - Cysts form in the renal cortex + medulla
Kidneys are ENLARGED
What is the inheritance pattern of MEDULLARY CYSTIC KIDNEY DISEASE
AD
What is the most common congenital RENAL anomaly?
HORSESHOE KIDNEY
In a HORSESHOE KIDNEY congenital abnormality, where is the kidney abnormally located in? Why?
LOWER ABDOMEN - Bec its embryological ascent from pelvis to abdomen is blocked -> Gets stuck in root of INFERIOR MESENTERIC ARTERY
What are the 3 types of ACUTE RENAL FAILURE? Which is the most common cause of ARF?
- PRERENAL AZOTEMIA - Decreased renal blood flow
- POSTRENAL AZOTEMIA - Obstruction of urinary tract downstream from kidney
- INTRARENAL AZOTEMIA : ATN - Necrosis of tubular epithelial cells = most common cause of ARF
What are the following values of PRERENAL AZOTEMIA: BUN:Cr, FENa, Urine Osm?
BUN:Cr > 15
INTACT Tubules: FENa500 - Can reabsorb Na+ and can concentrate urine
What is the difference between EARLY STAGE and LATE STAGE of POST-RENAL AZOTEMIA? List values.
Tubular Damage
EARLY STAGE: NO tubular damage - BUN:Cr>15, FENa500
LATE STAGE: YES tubular damage - BUN:Cr2%, Urineosm
In ACUTE TUBULAR NECROSIS (Intrarenal azotemia), what are the following ranges of BUN:Cr, FENa, and Urine Osm? What else is seen in the urine?
- BUN:Cr2%
3. Uosm
What are the two possible etiologies of ATN? Which portion of the nephron unit are particularly susceptible?
- ISCHEMIC - PT and early TAL (medullary)
2. NEPHROTOXIC - PT
Which etiology subtype of ATN (INTRARENAL Azotemia) is often preceded by PRE-RENAL azotemia? Why?
ISCHEMIC ATN is often preceded by PRE-RENAL due to DECREASED BLOOD SUPPLY to the tubules resulting in necrotic cells characterizing ATN
Which cause of NEPHROTOXIC ATN is associated with OXALATE crystals in the urine?
ETHYLENE GLYCOL (i.e. ANTIFREEZE) - Blue and sweet
What are the causes of NEPHROTOXIC ATN? What is the most common cause?
‘HEAR MU’
H- Heavy metals (Lead), E- Ethylene Glycol (oxalate crystals in urine), A- Aminoglycosides, R -radioactive dye , M - Myoglobinuria (from crush injury) , U- Urate (e.g. tumor lysis syndrome)
OR ‘ACRUEL’ - aminoglycosides/amphotericin B (NOT ATN, Type I RTA), crush injury (myoglobinuria), radioactive dye, urate, ethylene glycol, lead poisoning
Which cause of NEPHROTOXIC ATN is associated with CHEMO? What 2 prophylactic treatments are administered pre-chemo to decrease ATN risk caused by the chemo agent?
URATE - E.g. Acute leukemia pt receives chemo - Rapidly kills cells -> Rapid nuclear breakdown -> High uric acid -> Damages tubules via ATN
1. HYDRATION - To maintain good urinary flow + 2. ALLOPURINOL - To block uric acid buildup
Is ATN Irreversible or Reversible? How?
REVERSIBLE - Tubular cells have the ability to regenerate albeit it is a STABLE tissue so it takes some time to regenerate
What is the acid-base status, K+ state, BUN/Cr, urine production of ATN?
METABOLIC ACIDOSIS (Decreased excretion of organic acids NH4+ and HPO42-), HYPERKALEMIA (Decreased K+ secretion/excretion due to damaged tubular cells), Elevated BUN/Cr - AZOTEMIA, OLIGURIA (Decreased urine prdn)
How long does OLIGURIA associated with ATN last? Why?
2-3WEEKS bec tubular cells are STABLE CELLS (outside of the cell cycle, so it takes time to re-enter and regenerate)
What is the TREATMENT of ATN?
SUPPORTIVE DIALYSIS bec electrolyte imbalances can be FATAL
What is pathognomonic of EOSINOPHILS in the urine?
ACUTE INTERSTITIAL NEPHRITIS (Drug-induced)
What are the 5P causes of ACUTE INTERSTITIAL NEPHRITIS?
Pee (diuretics), Pain-free (NSAIDS), Penicillin, Proton Pump Inhibitors, rifamPin
What type of inflammatory reaction is involved in ACUTE INTERSTITIAL NEPHRITIS?
Drug-induced HYPERSENSITIVITY reaction involving the INTERSTITIUM and can spread to the TUBULES
What are the clinical Sx of ACUTE INTERSTITIAL NEPHRITIS?
OLIGURIA
FEVER
RASH
What is the Tx of ACUTE INTERSTITIAL NEPHRITIS?
Resolves with DRUG CESSATION
What are the causes of PAPILLARY NECROSIS?
‘SAAD PAPa’ with PAPillary necrosis
S- sickle cell trait/disease, A- analgesics, A- acute pyelonephritis, D- Diabetes mellitus
What are the clinical Sx of PAPILLARY NECROSIS? What could have been a precursor?
HEMATURIA + FLANK PAIN
Drug induced ACUTE INTERSTITIAL NEPHRITIS could have progressed to papillary necrosis
What is the most common cause of ACUTE KIDNEY INJURY in hospitalized pts?
ACUTE TUBULAR NECROSIS
