urinary Flashcards
- Define obstructive uropathy.
Anatomic changes in the urinary system caused by obstruction
- Be familiar with causes for obstructive uropathy.
Kidney stones, compression from a tumour, inflammation
- Describe the two most damaging effects of urinary tract obstruction.
Stasis of urine, with increases possibility of infection and stone formation
Progressive dilation of the renal collecting ducts and tubules (hydronephrosis) (glomerular filtration continues, so pressure builds up, first in renal pelvis, and then in tubules)
- Describe compensatory hypertrophy and hyperfunction.
If one kidney is obstructed, the body can compensate: in the unobstructed kidney the size of individual glomeruli and tubules is increased, (but not the total number of functioning nephrons). In this way, the unobstructed kidney can make up for the reduction in function of the obstructed kidney
- Define “calculi”.
Kidney stones
- What are the most common kidney stones composed of and where can they be located?
Calcium salts (oxalate or phosphate) due to factors including high urine calcium, caused by hyperabsorption of calcium from the intestines or hyperparathyroidism
- What are 2 disorders that can lead to the formation of calcium oxalate or phosphate kidney stones?
Hyperabsorption of calcium from the intestines or hyperparathyroidism
- Describe the two types of pain that can be experienced as a result of kidney stones and give the probable location of the stone for each type of pain.
Renal colic – excruciating pain in the flank and abdomen caused by a 1-5 mm stone moving into the ureter and stretching it
Dull, deep, mild to severe ache – in flank or back caused by a stone in the renal pelvis or calyces
- Know the term renal colic.
Type of pain you get when urinary stones block part of your urinary tract
- How are urinary calculi treated?
Removing stones, managing pain, reduction of further formation through increasing fluid flow and altering diet
- To what is lower urinary tract obstruction primarily related?
Storage of urine in the bladder or emptying of urine through the bladder outlet
- Describe neurogenic bladder – what does the type of dysfunction depend upon?
Bladder dysfunction caused by neurologic disorders. The type of dysfunction (whether incontinence or functional obstruction) depends upon where damage has occurred in the nervous system
- Name two physical obstructions of the lower urinary tract.
Scarring of the urethra (infection, surgery) & enlarged prostate
- Define glomerulonephritis. What is the most common contributing factor?
Inflammation of glomerulus caused by immunologic responses, infection, diabetes mellitus
Hypertension
- Identify the two common immune mechanisms that can lead to glomerulonephritis, and a common disease that is associated with each.
Type 2 (antibody reacting against antigen within the glomerulus – goodpasture syndrome)
Type 3 (deposition of circulating antibody/antigen complexes into the glomerulus – post streptococcal glomerulonephritis)
- Describe the series of steps in the development of glomerulonephritis as caused by these immune mechanisms.
Antibodies activate complement proteins, which summon macrophages and neutrophils, which secrete compounds that damage the glomerular cells. This increases glomerular permeability, which allow proteins and RBC to escape into filtrate. Proteinuria and/or hematuria develops
- Define: glomerular filtration rate. How is it usually estimated?
Production of filtrate by the glomerulus
Perfusion of the kidney, state of the tubules, post-kidney obstruction, insulin
- Describe nephritic syndrome, naming the disorder that is the usual cause.
Sudden excretion of blood cells, protein, diminished GFR, oliguria
Caused by inflammation that blocks the glomerular capillary lumen and damages the capillary wall (associated with postinfectious glomerulonephritis)
- Describe nephrotic syndrome, naming a disorder that can be the cause.
Massive proteinuria: excretion of 3.5 g or more of protein/day in urine, lipiduria
Hypoalbuminemia, edema (hallmark manifestation), hyperlipidemia
Result is a group of manifestations that includes thrombotic complications, increased risk of infection
Caused by increase in glomerular permeability (injury to podocytes), as a result of specific diseases (diabetes mellitus, SLE, minimal change disease)
- Define BUN – identify and explain the two facts that it reveals about the state of the kidney.
Blood urea nitrogen: concentration of urea in the blood
Glomerular filtration (because urea is filtered at the glomerulus, as the amount of blood that is filtered drops, BUN rises) & urine-concentrating capacity (because urea is reabsorbed from the nephron, if flow through nephron slows down, tubule is able to reabsorb more urea back into the blood)
- Identify and explain the one fact that the level of creatinine in the plasma reveals about the state of the kidney
Plasma creatinine concentration: creatinine is produced by the muscles, is filtered at the glomerulus, and never reabsorbed. Therefore, the plasma creatinine concentration only indicates the amount of filtration that is occurring at the glomerulus (GFR). If the glomerular filtration rate decreases, the plasma creatinine concentration increases
- Define AKI (include BUN and plasma creatinine), including whether it is reversible.
Sudden (less than two days) decline in kidney function with a decrease in glomerular filtration and accumulation of nitrogenous waste products in the blood (increased BUN and plasma creatinine)
Unlike chronic kidney disease/failure, it is potentially reversible, if can correct the cause before permanent kidney damage has occurred.
- What do the letters in “RIFLE” represent in terms of acute kidney injury?
: Risk – Injury – Failure – Loss – End stage disease
- List the 3 causes of AKI – identify the most common one.
Prerenal acute kidney injury (most common)
Postrenal acute kidney injury
Intrarenal acute kidney injury