Tubules- Clinical Flashcards
What is cause of the diarrheal form of HUS?
ingesting meat with EHEC (O157:H7) with shiga-like toxin
What is the nondiarrheal form of HUS associated with?
Oral contraceptive, cyclosporine, tacolimus, mitomycin C, bleomycin, ticlopridine or quinine, underlying malignancy, radiotherapy or familial recurrence
What are the 3 characteristics of all HUS syndromes?
microangiopathic hemolytic anemia and thrombocytopenia
Case: adult presents with acute sx of oliguria, flank pain, renal importment and arthralgia. Labs show eosinophilia. What has this pt taken to cause this?
Antibiotics or NSAIDs
Acute interstitial nephritis
What are the 2 most common causes of AIN?
Methicillin and NSAIDs
Case: pt presents with headaches, arthritis, msuclar aches, and a recent history of a peptic ulcer. Hx shows fibromyalgia. Biopsy shows chronic interstitial nephritis with papillary necrosis. What has this pt been taking to cause the problem?
Analgesics
Case: pt presents with pain, hematuria, HTN, and renal insufficiency. Imaging shows multiple bilateral renal cysts and cysts on the liver, spleen, and pancreas. What is the mutated gene to cause this disorder?
PKD1 on q16 –> can’t encode polycystin 1
polycystic kidney disease
Rhabdomyolysis, vigerous exercise, and ingesting of cooked meat can do what to serum creatinine level?
↑
What are the 3 causes of increased serum BUN independent of GFR?
GI bleed
Tissue trauma
Glucocorticoids
Case: pt presents with ↓ GFR, azotemia, and oliguria. You suspect prerenal azotemia. What happens to the serum BUN:Cr and FENa?
BUN:Cr > 15
RAAS activated –> ↑ reabsorption of urea
What causes prerenal ARF?
↓ blood flow
What is the main cause of POSTrenal ARF?
bladder outlet obstruction
If I say: “urine osmolality is increased early and the sediment is usually benign, with only hyaline and occasional granular casts” what is the Dx?
Prerenal azotemia
If I say: “urine that is isosmotic with the serum and urinary sediment that may contain tubular epithelial cells, granular cells, and amorphous material” what is the Dx?
Acute tubular necrosis
if I say: “urinary eosinophils and leukocytes” what is the Dx?
Acute interstitial nephritis
What 4 conditions give an FENa < 1%?
- Renal artery stenosis
- ↓ intravascular volume
- CHF
- Advanced cirrhosis
(anything with ↓ renal blood flow)
What is the 1 condition where the FENa is > 3%?
Acute tubular necrosis
What are the 4 electrolytes that msut be limited in pts with ARF?
K, Na, Mg, and phosphorus
This is the syndrome characterized by advanced liver disease and portal HTN associated with ARF.
Hepatorenal syndrome
Urinary Na < 20 mEq/L, urine osmolality > 500 mOsm/L, and a low FENa is consistant in hepatorenal syndrome and what other syndrome?
Prerenal disease
What are the 4 causes of chronic kidney disease?
Diabetes
HTN
Glomerulonephritis
Other/unkown
For those with chronic kidney disease, what is the target blood pressure?
<130/80
For those with chronic kidney disease and proteinuria, what is the target blood pressure?
< 125/75
What are the 2 anti-HTN meds for early renal disease?
ACEi’s
ARB’s
What are the 2 Tx’s for hyperphosphatemia seen in CRF?
Low-phosphorous diet
Phosphate binder
Pt’s with fluid overload, acidosis, hyperkalemia, hypernatremia, and uremic signs and Sx should get what?
Dialysis bitch
What are the 2 viral diseases that dialysis pts are at an increased risk for obtaining?
HBV and HCV
What is the first process in evaluating hyponetremia?
Measure serum osmolality
What are the 3 causes of isosmotic hyponatremia?
Severe hyperTGemia
Severe hyperproteinemia
Isotonic infusion of glucose, mannitol, or Gly
What are the 2 causes of hyperosmotic hyponatremia?
Severe hyprglycemia
Hypertonic infusions of glucose, mannitol, or Gly
Severe volume depletion, thiazides, and adrenal insufficiency can cause what form of hyponatremia?
hypo-osmotic hypovoluemic hyponatremia?
Edematous states and renal failure can cause what type of hyponatremia?
hypo-osmotic hypERvolemic hyponatremia
Hypothyroidism, addisons, reset osmostat, psychogenic polydipsia, and SIADH can cause what form of hyponatremia?
Hypo-osmotic euvolemic hyponatremia
Case: pt presents with clinical euvolemia, hypotonic plasma, urine
SIADH
What are the 3 most serious causes of SIADH?
Small cell carcinoma of the lung
CNS disorders
Drugs
What is the eqn to calculate total Na deficit?
Na deficit = TBW (lean body weight x 0.5) x (desired serum Na) - (current serum Na)
What is 1 treatment for hypervolumertric hyponatremia?
Diuretics
Case: pt presents with irritability, hyperreflexia, hypertonicity, ataxia, and recurrent seizures. What is the Dx?
Hypernatremia
What is the tx for hypovolemic hypernatremia?
Saline followed by hypotonic sln
What is the tx for hypervolemic hypernatremia?
Dialysis
What is the tx for euvolemic hypernatremia?
Free water
Li, demeclocycline or amphotericin B can induce what?
Nephrogenic DI
What 2 electrolyte imbalances may induce nepohrogenic DI?
Hypercalcemia + Hypokalemia
Which disorder has a high serum Na: DI or primary polydipsia?
DI
What is the sign that implies volume depletion?
Orthostatic hypotension
What is the sign that implies volume excess?
Edema
What is the normal range for an anion gap?
8-12
What are the causes of a high anion gap acidosis?
MUDPILES Methanol Uremia Diabetic Ketoacidosis Paraldehyde Isoniazid Iron Lactic Acidosis Ethanol Ethylene glycol Salicylates
What are the causes of type 4 renal tubular acidosis?
diabetes mellitus, interstitial nephritis, spironolactone, amiloride, triamterene, or cyclosporine
This is the difference between measured serum osmolality and calculated serum osmolarity.
Osmolar gap
What is the eqn for the calculated osmolar gap?
Calculated osmolar gap: (2Na) + (glucose/18 + BUN/2.8)
Why do we use the osmolar gap?
Screen for toxins
Case: pt presents to ER after attempted suicide from drinking large amounts of rubbing alcohol. Labs were being sent for osmolar and anion gaps. What would be the expected changes?
↑ osmolar gap
anion gap unchanged
What is the treatment for toxic alcohol ingestion?
Give them vodka.
Seriously. EtOH alters competes with ingested toxic alcohol and it facilitates its removal.
