| What are urinary stones? | Crystals and protein matrix, 4 steps to form (supersaturation, nucleation, aggregation, crystal retention)
Gall stones is a very frequent pathology, 5-10% of general population, age 20-60 male:female 3:1
tripled incindence at age 40, very frequent recurrence (more than 60% over 10 years)
Targets mostly high UT (pyelocaliceal cavirties/ureters) but also in bladder sometimes
Multidisciplinary tx. |
| What are different types of stones? | . |
| What are main ailmentary risk factors for developing stones? | ✔ Alimentary intakes:
o Dairy products.
o Animal proteins.
o Salt (favorizes the hypercalciuria).
o Aliments rich in oxalate (chocolate, dry fruits, spinach, sorrel, rhubarb, thea).
o Purines (giblets, delicatessen,…).
o Rapid sugars (fructose).
✔ The decrease in alimentary fibers consumption.
✔ The insufficient diuresis by the insufficiency in liquid intakes. |
| What are familial and urinary infection risk factors for stones? | a- Familial factors:
- We find a familial history in approximately 40% of cases. The cystinuria is the genetic disease mostly frequently found in this context.
b- Urinary infection:
- Certain germs, like proteus mirabilis, klebsielle and pseudomonas include the enzyme urease, which degrades the urea into a protein matrix upon which mineral salts precipitate in order to form phosphoammoniaco-magnesium stones. They mainly originate from coralliform stones= struvite |
| What are coraliform stones? | - Coralliform stones: designate stones that have radiologically coral shape, because they mold the pyelon, the calyces and the calyceal diverticulum. We equally talk of complex stones of the kidneys. |
| What are pH anomalies risk factors of stones? | - The normal urine pH is 5.8.
- An acidic pH favorized the formation of uric acid stones, cystine and calcium oxalate.
- An alkaline pH favorizes the infectious lithiasis and phospho-calcium stones. |
| What are anatomic anomalies risk factors for stones? | - Certain anatomic anomalies of the kidneys or the excretory tract favorize urinary stasis and, thus, stones formation.
- Once the diagnosis is imposed, we need to treat the stone and the anatomic anomaly, if possible, in order to avoid recurrences.
- We can name some anatomic anomalies such as pyelo-ureteral junction syndrome, calyceal diverticulum, the horsehoe kidney «arcuatus » , the mega-ureter , and the vesico-ureteral reflux. |
| What are medications causing stones? | Drugs causing it are infrequent 1%, may be metabolic disorder caused by it or crystallization w/metabolites.
Most one is indinavir (anti-HIV protease) may be alkaline and solublized in acid, not visible in ASP and scan
If indinavir causes lubar pain stop tx aviod NSAIDs, increase diuresis and obtain urine acidity. |
| How is the revealing mode of lithiasis? | - The lithiasis urinary disease mainly affects the upper urinary tract.
- The most common mode of revealing is renal (nephritic) colic crisis. It is then a question of knowing how to recognize the signs of seriousness which can be vital prognostic.
- However, urinary stones can be asymptomatic and discovered incidentally during imaging (ASP, reno-vesical ultrasound), or the assessment of chronic renal failure.
- Low urinary tract lithiasis is restricted to highly targeted patient populations, such as patients with severe neurological conditions (particularly para- and quadriplegic patients). It always translates a bad bladder emptying which will have to be followed up and treated to avoid the recidivism (tendency to relapse). |
| What is nephritic colic crisis caused by lithiasis? | 80% of renal colics are caused by stones in adults, acute lumbo-abdominal pain from severe tension of excretory tract of UUT upstream of an obstruction.
Pressure increase is due to (edema generated in contact w/calculus promoting retention of overlying urine and block of calculus passage, or due to stimulation of vasodilator E2 PGs due to intracavitary hyperpressure) |
| How is the typical renal colic decription? | ● • Brutal (severe) start.
● Acute pain, without analgesic position.
● Unilateral lumbar pain, radiating downwards and forwards along the ureter to the external genitals.
● Evolution by paroxysmal crisis.
● Agitation and anxiety.
● Urinary functional signs: pollakiuria (extraordinary daytime urinary frequency), urinary burns, hematuria (if the calculus is at the level of the uretero-vesical junction).
● Digestive signs: nausea, vomiting, transit stop (ileus), see pseudo-occlusive table. |
| What are clinical exam findings of renal colic? | ● Interrogation: personal and family history of urolithiasis, taking of lithogenic drugs, search for factors favoring renal colic.
● Apraxia (is the normal interval or period of intermission in a fever. Also, the absence of a fever).
● Soft abdomen, sometimes bloat.
● Lumbar fossa sensitive to palpation and percussion ((Positive lumbar ponch).
● Renal colic is resolvable in the majority of cases under symptomatic analgesic treatment well conducted. |
| How is complicated renal colic? | - Is characterized either by the field (pregnancy, chronic renal insufficiency, transplanted kidney, single kidney, known uropathy, pyelonephritis ...), or by the existence immediately or secondarily of signs of gravity.
- It requires urgent surgical drainage of the urine (either by JJ probe or by nephrotomy). |
| What is febrile nephritic colic/obstructive pyelonephritis? | This is a medical and surgical emergency. It corresponds to infected urine upstream of an obstructive calculus of the upper urinary tract and infection of the renal parenchyma.
- The main clinical signs are:
• Fever> 38 ° C.
• Chills.
• Skin marbrures, hemodynamic instability.
• Positive urine strip (leucocytes +, nitrite +, + bacteria). |
| What is anuric renal colic? | Three mechanisms are at its origin:
• Functional acute renal insufficiency of septic origin.
• Bilateral calculi = rare situation, reflection of a very active lithiasis pathology (cystinuria, primary hyperparathyroidism, important hyperuricemia-hyperuricuria...).
• Single kidney: congenital, remnant or functional.
• It results in acute renal failure with a very high elevation of creatinine and frequent ionic disorders (hyperkalemia). |
| What is hyperalgic nephritic colic? | - It corresponds to a pain of nephritic colic not calmed by a symptomatic analgesic treatment well conducted with use of NSAID IV and morphine IV in titration.
- It then requires hospitalization with reassessment of pain. If the pace and severity of crises do not disappear, emergency urine drainage is necessary.
- Sometimes, the pain arises suddenly. This corresponds to the rupture of the excretory pathway or rupture of fornix (junction of the excretory pathway on the renal straw) . In this case, if the obstacle persists, it can cause a large perineal urinoma, also requiring emergency drainage of the excretory tract. |
| What is the DD of lithiasis? | GI (hepatic colic, cholecytisis, diverticulitis, appendicitis, strangulated inguinal hernia)
GYN (ectopic pregnancy, torsion ovarian/appendix)
Medical pathology (pneumonia, lumbar osteoarthritis)
Vascular pathology (abdominal aortic aneurysm, mesenteric infarct)
Segmental renal infarct
Papillary necrosis. |
| How is hematuria in lithiasis? | -It is most often microscopic discovered with the urinary strip but can be macroscopic.
- It results from irritation of the urothelium by calculi. |
| How are urinary infections in lithiassi? | - The urinary-lithiasis infection association is frequent. However, it is difficult to determine whether the calculus was secondarily infected or whether the infection preceded the calculus and was responsible for its formation.
- Several situations are possible:
• Asymptomatic bacteriuria.
• Recurrent cystitis.
• Recurrent pyelonephritis |
| How is renal insufficiency in lithiasis? and asymptomatic? | The kidneys can be destroyed by bilateral asymptomatic stones. It is most often coralliform stones.
✔ Asymptomatic:
- An asymptomatic calculus can be discovered accidentally on an ASP, an ultrasound or a scanner made for other reasons. |
| How are LUT lithiasis? | - The stones of the lower urinary tract (bladder, urethra) are more rare.
- The bladder stones are most often the fact of a subvesical obstacle (benign prostatic hypertrophy, cervical sclerosis), or an intravesical foreign body (son?(fils), bladder catheter balloon).
- They are usually found in front of functional urinary signs: hematuria, urinary burns, pollakiuria.
-In contrast, in well-targeted populations, lithiasis of the lower urinary tract is very common. This is mainly the case of neurological patients with severe motor impairment: quadriplegia, advanced multiple sclerosis ... |
| What is urine strip test for dx of lithiasis? | Rapid detection of hematuria or UTI, any pt presenting sus acute renal colic, long-term care measures urine pH and follow-up.
excellent test, sensitive enough detects leukocyturia >10^4/ml
Nitrite detection indicates bacteria, threshold 10^5
Negative if no leukocyturia/bacteruria, risk for false negative very low (3%) but possible for nitrite case of low bacteriuria, nitrate restricted diet, infection by atypical bacteria not producing nitrite) |
| How are cytologies of urine in lithiasis dX? | - Is to be performed in addition to the urine test strip if it is positive.
- It is essential in case of suspicion of obstructive pyelonephritis and must be performed before any antibiotic therapy.
- A culture and an antibiogram must be carried out in order to secondarily adapt the antibiotherapy. |
| How are blood cultures and std biology for lithiasis dx? | c- Blood cultures :
- They must be carried out systematically and repeatedly in a fever> 38.5 ° C during obstructive pyelonephritis.
- They allow detecting a possible sepsis.
d- standard Biology :
- FNS.
- Creatinine.
- Ionogram (Na, K, Cl, CO2). |
| What is metabolic balance of first intention in dx of lithiasis? | ● A blood test: serum creatinine, serum calcium, fasting blood glucose, serum.
● A collection of urine over 24 hours: creatinine, total volume, calcium, sodium, urea, urates.
● A report (test/collection of) on morning urine (fasting): pH, density, dipstick test* (en francais, BU: bandelette urinaire), crystalluria.
- The conditions for 24-hour urine collection must be precise.
- It is important that the patient does not change his eating habits for the achievement of this test (bilan in French, probably means test/report).
- It must be done more than one month after an acute episode or urological. |
| What is IR spectrophotometry used in lithiasis dx? | - It can be performed on spontaneously expelled stones or on fragments collected after treatment.
- It makes it possible to precisely determine the molecular and crystalline composition of the calculi.
- Depending on the composition and structure of the calculation, different causes may be proposed. |
| What is use of radio examinations in lithiasis dX? | - In emergency, the imaging examinations are indicated to affirm the diagnosis of renal colic (dilation of the superior excretory way, calculi...), to evaluate the gravity (single kidney, urinoma ...), and to specify the chances of spontaneous expulsion. Calculi (size, location and morphology).
- Their indication and the acceptable time to obtain them are dependent on their accessibility and the clinical context (simple NC*, complicated NC*, special fields, diagnostic doubt...).
- Imaging is also essential before an invasive urological treatment to better specify the morphology of the urinary tract and the characteristics of the calculation. |
| What is KUB use in lithiasis dx? | - Very easy to perform in an emergency. However of poor sensitivity and specificity in providing evidence of the presence of a calculi (40 to 58% and 60 to 77% respectively).
- Therefore, KUB should not be done in isolation (alone) and should be coupled with another imaging test.
- Moreover, it only informs about the presence of a stone and not about the possible complications.
- Calculi are considered opaque to x-rays (radiography), or simply radiopaque, when they are seen on KUB.
- Calculi are considered radiolucent (radio-transparent) when they are only visible on echography (ultrasound). Radiolucent (radio-transparent) calculi are seen on the scanner.
- When the calculus is visualized on the KUB, it can be used to follow the progress of the calculus. |
| What is use of reno-bladder US? | - Noninvasive, inexpensive and fast, but operator-dependent.
- The ultrasonography (echograpghy) of the excretory urinary pathways is associated in combination with KUB and can be used in the management (treatment) of renal colic in emergencies.
- It best detects the stones located at the pyelo-ureteral and uretero- bladder junction, especially if it is performed with full bladder.
- The calculus appears hyperechoic, with posterior acoustic shadowing |
| How does reno-bladder US confirms lithiasis dx? | - It confirms the clinical diagnosis of NC by objectifying (showing) a dilation of the pyelocaliceal cavities and / or the ureter (image). However, any dilatation does not mean obstruction (hypotonic sequelae (or sequential Hypotonia – both are correct) of an obstacle, bladder distention during the examination), and any obstruction does not immediately result in an expansion that can appear a few hours later (20 to 30% of the sudden obstructions on ureteral calculus are not identified (or objectified since the French document said objectivées).
- It also describes the renal parenchyma, a thinning which can be explained by a chronic obstacle. |
| How is use of abdominal CT w/out contrast in lithiasis dx? | - It is a quick test, independent of the patient and the operator, but radiating.
- ALL calculi are visible on the scanner, apart from the medical calculi (I asked a fellow French student about this sentence and apparently it is translated into exactly). CT without injection has a very high sensitivity (96%) and specificity (98%) for the diagnosis of urolithiasis and detects millimeter calculations.
- In addition to the direct visualization of the calculus, other indirect signs can help in the diagnosis: dilation of the pyelocaliceal cavities, infiltration of the perirenal or peri-ureteral fat, thickening of the ureteral wall with next to (near) the calculi (rim sign)… (image 10).
- In addition, the scanner makes it possible to measure the Hounsfield density/unit (HU) of the stones and thus to orient towards a particular composition of the calculi and to predict the effectiveness of the ECL |
| What are treatment modalities of lithiasis in cases of emergency? | - Treatment (management) in case of an emergency is mainly that of renal colic and aims to relieve the patient when it is simple, and to divert urine in emergency (I guess he means introducing a catheter to empty the urine) when it is complicated. |
| What is tx of simple renal colic? | ✔ Non-steroidal anti-inflammatories:
- Two mechanisms of action:
● They block the cyclo-oxygenases involved in the inflammatory cascade. They reduce local edema and inflammation and lead to relaxation of the smooth muscle fibers of the ureter, thus reducing (decreasing) peristalsis.
● They decrease the glomerular filtration rate.
Analgesics:
• Level 1 (paracetamol): in combination with NSAIDs in case of low intensity pain.
• Level 3 (morphine):in case of contraindication to NSAIDs. In combination with NSAIDs in the case of significant pain. In case of resistance to NSAID therapy., To be used in the form of IV titration of morphine hydrochloride.
Water restriction if painful phase, urine seiving |
| How is tx of complicated acute renal colic? | - The treatment is then surgical and consists of draining urine from the upper urinary tract.
- Urine drainage is in the majority of cases ensured by a ureteral catheter, which can be internal (then called probe JJ), or external
- In the case of the JJ probe, the upper loop has its place in the ( pyelon)??? and the lower loop in the bladder.
- The external ureteral catheter is often preferred to the JJ probe in case of purulent pyelic urines. In this case, the conversion to JJ probe is generally performed after 48 hours of apyrexia. |
| What are managements in case of drainage failure? | - In case of failure of drainage of the urine by the natural ways, a percutaneous nephrostomy is carried out under ultrasound control. Its installation requires dilated pyelocalicielles cavities.
- In all cases, a pyelic urine sample must be taken intraoperatively for bacteriological analysis. |
| How is management in case of obstructive pyelonephritis? | - In case of obstructive pyelonephritis, parenteral antibiotic therapy should be instituted as soon as possible after the bacteriological samples taken:
• Associating a C3G with an aminoglycoside.
• Secondarily adapted to the antibiogram.
• Oral relays can be considered at 48 hours of apyrexia.
• Total duration of 10 to 21 days. |
| What is extracorporeal lithotripsy (ECL) surgical tx of lithiasis? | - This is a non-invasive method.
- Principle: an extracorporeal generator produces acoustic waves. These are focused on the calculation by a radiological tracking system in order to spray it.
- Technique: performed on an outpatient basis, under simple sedation. An ECBU must be done a few days before and an ASP the day before to check that the calculus is still in place.
- Indications: first-line for the treatment of kidney stones <20 mm. Radiopaque stone (they must be visible at the ASP), density <1000 UH. Reference treatment in children. |
| What are CI and complications of ECL? | - Contraindications:
o Pregnancy.
o Untreated urinary infection.
o Obstacle downstream of the stone.
o Aneurysm of the renal artery or aorta.
o Uncorrected bleeding disorders.
- Complications:
o CN post-LEC by migration of residual fragments (20%).
o hematuria.
o Urinary infections.
o Renal hematoma. |
| What is ureteroscopy surgical tx of lithiasis? | - Principle: retrograde natural introduction of a ureteroscope to visualize and work in contact with the stones.
- Extraction of the calculus at the laser ± fragmentation clamp. Risk of ureteral lesions (perforation, stripping).
- Indications:
o LEC-resistant stone (density> 1000UH), or contraindication of LEC.
o In competition with LEC for kidney stones <2 cm.
o Stones of the pelvic ureter.
- Complications:
o hematuria.
o Pain of renal colic by ureteral clot.
o Urinary infection. |
| What is percutaneous nephrolithotomy NPLC surgical tx of lithiasis? | - Principle: percutaneous puncture of the kidney under ultrasound and fluoroscopic control (X-rays) (patient in ventral or lateral decubitus), then progressive dilation of the path obtained allowing the establishment of an access sheath and the introduction of a nephroscope. Then visualization, fragmentation and extraction of stones.
- Indications: reference treatment for stones> 2 cm, coralliform or kidney complexes.
- Risks:
o haemorrhagic and infectious complications;
o intra-abdominal organ lesions (colon ...). |
| How is open surgery tx of lithiasis? | - Little indication today (1% of treatments for kidney stones).
- Polar or total nephrectomy for stones with parenchyma destroyed opposite.
- In association with anatomical abnormalities, joint treatment (ex: cure of pyelo-ureteral junction syndrome and pyelotomy for pyelic calculus). |
| How is tx of bladder stone? | - Fragmentation during a cystoscopy (pince à calcul, compressed air).
- Conventional surgery (vesical size) if stone size too important. |
