Renal Diseases Flashcards
(118 cards)
In primary care, often have reason to be concerned about the possibility of kidney disease in kids who present with ____ or __ in their urine or with __ or ___ problems
blood or protein in their urine or with hypertension or growth problems
Functions of the kidney
- Filtration and Elimination of waste products in the form of blood urea nitrogen (BUN), uric acid and creatinine
- Maintain circulatory volume and acid-base balance
- Hormonal regulation and Hormonal response
- Blood pressure regulation
in dehydration/shock situations, the kidney will maintain circulatory volume at the expense of ____, which, along with the lung, maintains the optimum ____
acid-base regulation
pH of our blood.
The kidney is responsible for producing what?
- renin
- erythropoietin
- active form of vitamin D
what is Renin?
a key component in the renin-angiotensin-aldosterone regulation of blood pressure
What is erythropoietin
The hormone which signals the bone marrow to produce red blood cells
How does ADH affect the kidney
increase reabsorption of H20
How does PTH affect the kidney
Increase reabsorption of Ca2+
How does aldosterone affect the kidney
Increase reabsorption of Na+ and excretion of K+
-increases BP
How does ANH,ANP hormone affect the kidney?
Decrease reabsorption of Na+
Describe the renin-angiotensin cascade
Decreased BP–> renin released from kidney–> cleaves angiotensinogen from liver into angiotensin I–> cleaved by ACE from lung into angiotensin II–> vasoconstricts BV and stimulates adrenal cortex to release aldosterone–> increase Na+ and H20 reabsorption = increase BP
Clinical presentation of renal failure
- AMS
- N/V
- malaise
* caused by significant electrolyte imbalances
Presentation of chronic renal insufficiency
- HTN
- various lab abnormalities: proteinuria or elevated BUN or Cr
- growth failure
Causes of pre-renal acute failure
- etiologies which decrease circulating volume:
1. blood loss,
2. dehydration,
3. shock including anaphylaxis, cardiogenic or septic, heart failure) - or blocked blood flow to the kidneys:
4. renal artery thrombi/masses or
5. trauma
Lab findings with pre-renal failure
- High BUN and Cr w/ BUN greater than Cr*
- Low urine Na+**
- High urine specific gravity*
- low urine output
Causes of intrinsic renal failure
- damage to the tubules (shock, toxins)
- microvascular injury (HUS)
- glomerular injury (PSGN, HSP, SLE)
- Interstitial cell injury (Drugs)
Describe the prognosis of intrinsic renal failure
While some intrinsic renal failure is recoverable, some of the causes listed here can result in permanent renal damage and some degree of chronic renal insufficiency/failure
Causes of post renal failure
- anything that causes obstruction to urine flow such as anatomical abnormalities:
- UPJ obstruction
- posterior urethral valves,
- neurogenic bladder
- or acquired obstructions:
- renal stones
- Foreign body,
- masses,
- trauma
in post renal failure, Because the obstruction needs to be bilateral or at the level of the bladder or lower to cause symptoms of acute renal failure, the consequence of ___ is rarely seen
poor urine output
Lab findings associated with intrinsic renal failure
- High BUN and Cr with Cr greater than BUN*
2. high urine Na+, urine sediment
Lab findings associated with post renal failure
- high urine Na+
2. low urine specific gravity*
Whatever the cause, as renal function decreases the serum creatinine level will ___.
Ex- a child whose normal Cr is 0.5, who now has a Cr of 2.0, how has their GFR changed?
rise proportionally
-so that for every doubling of serum creatinine, the renal clearance, expressed as glomerular filtration rate (GFR), has been halved.
For example a child whose normal Cr is 0.5, who now has a Cr of 2.0 (doubled twice 0.5 to1, 1 to 2) has decreased their GFR to 25% (halved twice 100%to50%,50%to 25%).
Obvious renal failure does not result until ___% of nephrons are lost in both kidneys (progressively)
75%
End-stage renal disease is defined by
as GFR less than 15% and requires dialysis as well as medications to take the place of hormones the kidney would have produced