1 - Renal Patho Flashcards
What is the most common types of urinary dysfunction?
Infection (duh)
What is obstructive uropathy?
Anatomic changes in the urinary system caused by obstruction
Define the following
hydroureter
hydronephrosis
ureterohydronephrosis
accumulation of urine in the ureter
enlargement of renal pevlis and calyces
dilation of both ureter and pelvicaliceal system
What causes tubulointerstitial fibrosis?
Imbalance between cytokines (causing breakdown) and growth factors (causing rebuilding)
Fibroblasts deposit an excessive amount of extracelullar matrix, leading to fibrosis of the tubule
Angiontensin II and aldosterone are involved in creating this imbalance
Relief of a urinary tract obstruction of one kidney is usually followed by ________
a brief period of diuresis
postobstructive diuresis
Can sometimes be extreme and require intervention
What is nephrolithiasis?
Kidney stones, renal calculi
Why is the prevalence of stones dependent on geographic location?
average temperature, humidity, rainfall influence fluid intake and dietary patterns
Most stones are made up of:
70-85% are calcium oxalate or phosphate
Which tends to cause calcium phosphate stone formation: Urine that is alkaline or acidic
Alkaline
Which tends to cause uric acid stones: Urine that is alkaline or acidic
acidic
Name four crystal growth inhibiting substances:
- Uromodulin
- K citrate
- pyrophosphate
- magnesium
Stones smaller than _______ have a 50% chance of passing spontaneously.
Stones larger than ______ will never pass spontaneously.
5mm
1cm
What is renal colic?
moderate to severe pain flank pain that radiates depending on where the obstruction is
Prevention of stones includes drinking enough water to result in ________ L of urine per day
2.5
What substance in soda causes stones?
phosphoric acid
Lower motor neuron disorders may cause ______
Upper motor neuron disorders may cause _______
detrusor hyperreflexia
detrusor areflexia
What is the difference between overactive bladder syndrome and underactive bladder syndrome?
OAB results from detrusor overactivity, but the detrusor isn’t strong enough to empty the bladder, resulting in urinary retention. It causes symptoms of urgency.
UAB is caused by bladder contractions that aren’t strong enough to totally empty the bladder. They can initiate, but they can’t pee completely.
What usually causes bladder outlset obstruction in women with pelvic organ prolapse?
A cystocele
Due to decreased vaginal tone, the back of the bladder collapses below the neck of the bladder, causing difficulty emptying the bladder, and weakening the detrusor muscle
The detrusor muscle hypertrophies, which initially compensates but ultimately leads to poor bladder wall compliance
What is the most common renal neoplasm?
Renal cell carcinoma
What is the most common bladder malignancy?
urothelial carcinoma
appears on the inner lining of the bladder
What constitutes recurrent UTIs?
thre or more in 12 months
The pathogen most commonly responsible for UTI is:
E Coli (80-85%)
________ mechanisms are the major cause of acute glomerulonephritis
immune
Most common: Type III hypersensitivity 2/2 deposition of circulating immune complexes in the glomerulus
Nephrotic syndrome is characterized by _______
Nephritic syndrome is characterized by _______
Both are features of different types of _________
gross proteinuria and lipid sediments
red blood cells escaping through the membrane and proteinuria (less severe)
glomerulonephritis
Severe glomerular disease causes: (3)
oliguria
hypertension
renal failure
Why does diabetic nephropathy occur?
- Accumulation of glycosylated end products
- Inflammatory growth factors
- vascular changes 2/2 hyperglycemia
Why does lupus cause nephritis?
glomerular deposition of immune complexes
complement activation
What causes nephrotic syndrome?
disturbances in the glomerular basement membrane and podocyte injury
leads to loss of negative charged proteins and increased permeability
Nephrotic syndrome most often occurs with ________
Nephritic syndrome most often occurs with _________
minimal-change nephropathy (more common in kids)
infection-related glomerulonephritis, RPCG, lupus
Nephrotic syndrome is treated by consuming a moderate _________ diet
protein restricted
low fat
salt restricted
Define the following:
Renal Insufficiency
Renal Failure
ESRD
25% of renal function / GFR < 25-30
significant loss of renal function
10% of renal function
Both _____ and _____ refer to indications of accumulated nitrogenous waste products in the blood
uremia
azotemia
An AKI has a mortality rate of _______
50-80%
The most common cause of AKI is:
reduced perfusion (pre-renal)
prerenal AKI can result from renal vasocontriction caused by:
NSAIDs
Contrast
When renal perfusion is compromised, the kidney can initially maintain the GFR by afferent _______ and efferent _______
dilation
constriction
______ antibiotics are particularly likely to cause nephrotoxic ATN
aminoglycosides (getnamicin, neomycin, tobramycin)
Which tubule is most susceptible to injury?
Why?
proximal
Designed to be highly reabsorptive with a high surface area and thick brush border
tends to absorb the majority of nephrotoxic things
Which AKI is associated with complete anuria?
postrenal obstruction
What are the symptoms of uremia?
hypertension
anorexia
n/v/d or constipation
malnutrition and weight loss
pruritis
edema
anemia
CV/neuro/skeletal issues etc
Why does renal disease cause hypocalcemia?
impaired renal synthesis of calcitriol leads to decreased intestinal absorption of calcium
phosphate excretion is reduced, so phosphate binds to calcium and further reduces serum calcium levels
decreased calcium levels spark increased PTH secretion, which results in bone breakdown (secondary hyperPTH)
Why does renal disease cause dyslipidemia?
uremia causes a deficiency in lipoprotein lipase and hepatic triglyceride lipase
Causes dysregulation of HDL and LDL levels
Is the urine of infants more or less dilute?
Why?
More dilute
Very low concentrating ability
The medulla is highly perfused and the loops are short
The immature kidney isn’t as responsive to vasopressin
Why is urea excretion low in infants?
They are in a high anabolic states and use pretty much any available proteins for growth
no proteins are getting broken down, so no urea is formed
Compared to adults, the percentage of ECV in the newborn is ______
nearly double!
Glomerulonephritis begins with the deposition of _______ in the glomerulus
antigen-antibody complexes of IgG and C3 complement
Glomerulonephritis in children usually follows a ______ infection
Group A beta hemolytic streptococcal
Symptoms of glomerulonephritis generally begin _______ weeks after a URI
and ______ weeks after a skin infection
1-2 weeks
up to 6 weeks
What percentage of children with PSGN develop end stage renal disease?
1%
95% have a complete recovery
What is the most common form of glomerulonephritis in children worldwide?
IgA nephropathy
What percentage of children with IgA require dialysis or transplantation?
20-40%
What causes IgA nephropathy?
abnormal IgA is produced by the bone marrow, which can activate compliment and spark an immune inflammatory reaction
The ensuing complex is deposited in the glomerulus
What is the most common community acquired cause of acute renal failure in young children
Hemolytic Uremic Syndrome
What is Hemolytic Uremic Syndrome?
hemolytic anemia that leads to renal impairment
What causes hemolytic uremic syndrome?
verotoxin from E. Coli is absorbed from the intestines into the blood
It binds to leukocytes and is transported to the kidney
In the kidney, inflammatory cascade leads to lysis of glomerular capillary endothelial cells which ends up clotting the glomerular arterioles
glomerular filtration decreases
Narrowed vessels damage red blood cells, hence the hemolytic anemia
HUS is usually preceeded by:
A GI diarrheal infection
Approximately 95% of cases of nephrotic syndrome in children occur without _______
a history of systemic or pre-existing renal disease
What is a Wilms Tumor?
Nephroblastoma
abnormal proliferation of renal stem cells
How do most Wilms tumors manifest?
90% are an asymptomatic enlarging upper abdominal mass in a health, thriving child
Why would an increase in efferent arteriolar resistance cause increased reabsorption in the peritubular capillaries?
Decreased flow through the efferent arteriole means decreased flow through the peritubular capillaries
this means decreased hydrostatic pressure in the peritubular capillaries, which means increased reabsorption
