module 8 Flashcards
presence or formation of stones in an organ or in a duct of a body
Lithiasis
formation of kidney stones in the kidney
nephrolithiasis
presence of stones in the urinary tract which can include kidneys,urethers or bladder(urethera)
urolithiasis
uremia forms?
urine stones
it is condition characterized by the swelling or dilation of both of the kidneys due to the accumulation of urine as there will be a blockage of urine.
hydronephrosis
Small, hard Stones (1-3mm);
- Stones have sharp edges
- Radio-Opaque
calcium stones( 80% )
Large Stones (Molds to Renal
Pelvis/Calyces) ʹ Hence Staghorn
Chronic Irritation of Epithelium surrounding
Stone > Squamous Metaplasia
Triple Phosphate/Struvite/ “Staghorn” Stones
15%
may cause flank discomfort, recurrent
infection or persistent hematuria
- may remain asymptomatic for years and
not require treatment
calyx
- tend to cause UPJ obstruction renal pelvis
and one or more calyces
pelvis
- often associated with infection
- infection will not resolve until stone
cleared - may obstruct renal drainage
staghorn calculi
- 5 mm diameter will pass spontaneously in
75% of patients the three narrowest
passage points for upper tract stones
include: UPJ, pelvic brim, UVJ
ureter
Factors promoting stone formation
- stasis (hydronephrosis, congenital
abnormality) - medullary sponge kidney * infection
(struvite stones) - hypercalciuria
- increased oxalate
- increased uric acid
Loss of inhibitory factors
- magnesium (forms soluble complex with
oxalate) - citrate (forms soluble complex with
calcium) - pyrophosphate
- glycoprotein
- Account for 80 - 85% of all stones
- Ca2+ oxalate most common, followed by
Ca2+ phosphate description - grey or brown due to hemosiderin from
bleeding - radiopaque
calcium stones
- Female patients affected twice as often as
male patients - Etiology and pathogenesis
o account for 10% of all stones
o contribute to formation of staghorn
calculi
o consist of triple phosphate (calcium,
magnesium, ammonium)
o due to infection with urea splitting
organisms NH2CONH2 + H2O ––>
2NH3 + CO2
o NH4 alkalinizes urine, thus
decreasing solubility
struvite stones
- Account for 10% of all stones
- Description and diagnosis
o orange colored gravel, needle
shaped crystals
o radiolucent on x-ray
o filling defect on IVP
o Radiopaque on CT scan
o Visualized with ultrasound
Uric Acid Stones
- Autosomal recessive defect in small bowel
mucosal absorption and renal tubular
absorption of dibasic amino acids - Seen in children and young adults
- Aggressive stone disease
- Description
o hexagonal on urinalysis
o yellow, hard
o radiopaque (ground glass)
o staghorn or multiple
o decreased reabsorption of “COLA”
o cystine (insoluble in urine);
ornithine, lysine, arginine (soluble in
urine)
Cystine Stones
- Infection of the renal parenchyma with local
and systemic manifestations of infection - may be classified as uncomplicated or
complicated
Acute Pyelonephritis
