Flank Pain Flashcards
DDx of flank pain (12, in women 2 more, and 3 more abdominal pathologies)
Muscular sprain
Nephrolithiasis/ureteric colic
Leaking/ruptured abdominal aortic aneurysm (AAA)
Spinal pathology (fractures, metastases, disc prolapse) Testicular torsion (very unusual in an elderly person)
Pyelonephritis (unusual in a man)
Perforated peptic ulcer
Renal cancer
Abscess (perinephric, renal) Basal pneumonia
Ectopic pregnancy
Ovarian torsion
Pancreatitis
Diverticulitis
Appendicitis
Site of kidney stone pain?
Unilateral
May radiate from loin to groin
Character of ureteric stone pain?
Ureteric stones give a colicky (waxing and waning) pain because of periodic spasms of the ureteric smooth muscle walls trying to dislodge the blockage.
How to differentiate ureteric vs kidney stones?
Constant = kidney Colicky = ureteric
What is an achey pain in the flank suggestive of?
Musculoskeletal
What is a sharp shooting pain in the flank suggestive of?
Nerve impingement
What pain typically radiates to the groin
Ureteric
What pain typically radiates down the leg
Lumbar nerve root pain
Typical radiation of ureteric pain
To the groin
Typical radiation of lumbar nerve root pain
Down the leg
If flank pain is said to be excruciatingly painful what is it suggestive of?
Kidney stones
What questions should you ask in the when checking the history of the flank pain? (After socrates, 17)
Fevers, rigors, night sweats Dehydration Nausea and vomiting Haematuria Lower UTI symptoms (FUN HIIPS - frequency, urgency, nocturne, hesitancy, intermittency, ) Cloudy or offensive smelling urine Leg weakness
What does leg weakness suggest in flank pain?
Spinal pathology
What does cloudy or offensive-smelling urine suggest in flank pain?
Infection
What does nausea and vomiting suggest in flank pain? (3)
This is more typical of visceral organ pathology (e.g. ureteric stones, biliary colic, appendicitis)
What dehydration indicate?
Concentrated urine and therefore kidney stones
What do fevers, rigors and night sweats suggest in flank pain? (3)
A markedly raised fever indicates an inflammatory process, potentially pyelonephritis or sepsis. The fever of malignancies (e.g. renal cell carcinoma) is typically intermittent, unlike in infection.
Difference between fever in inflammatory processes vs malignancy?
Malignancies is intermittent
What PMHx should you inquire about in flank pain? (5)
Previous kidney stones Recurrent cystitis Atherosclerotic disease Long-standing back pain Kidney disease
What type of stone does recurrent cystitis predispose to?
Struvite
What drugs can lead to kidney stone formation? (3)
Indinavir, aciclovir, and acetazolamid
What does FHx of kidney stones suggest in someone presenting with kidney stones?
This may indicate a (rare) inherited condition such as cystinuria.
What do people with ureteric colic look like on examination?
Unable to sit still and thus tend to writhe in pain.
What do people with peritonitis look like on examination?
Rigid and motionless, as any movement causes pain.
What abdominal sign is seen in individuals with flank or loin tenderness
Tenderness in the flank or loin, particularly in the costovertebral angles
What is the difference in testicular tenderness referred from renal stones and testicular pathology (e..g torsion)?
Renal stones is mild, otherwise its suggestive of a testicular cause
What is a central, laterally expansive abdominal mass suggestive of?
A leaking AAA
What does an easily felt popliteal pulse suggest?
Popliteal aneurysm
What is a popliteal aneurysm associated with?
50% also have an AAA
What is the pH of the urine of a patient with renal stones?
Usually acidic
What is an alkaline pH suggestive of?
The presence of urease-producing bacteria (e.g. Proteus, Pseudomonas, Klebsiella) that can predispose to stone formation.
What Ix should you carry out in a Px suggestive of urinary stones? (9)
Urinalysis (haematuria, WBC, leucocyte esterase, pH and nitrites)
Urine microscopy, culture and sensitivity
FBC and CRP (WCC)
Urea, creatinine and electrolytes
Serum calcium, phosphate and urate (looking for what type of stone)
CTKUB
What should you look for in urine microscopy, culture and sensitivity? (3)
Blood, evidence of infection (white cells, bacteria…) and crystals
What do red cell casts indicate?
Red cell casts indicate glomerular damage
What do white cell casts indicate?
White cell casts suggest pyelonephritis
The presence of what indicates pyelonephritis?
White cell casts
The presence of what indicates glomerular damage?
Red cell casts
What Ix is key in pancreatitis?
Serum amylase
What Ix is key for a perforated peptic ulcer?
Erect CXR looking for air under the diaphragm
What Ix suggest renal failure? (3)
High creatinine, urea and K+
When should you admit someone into hospital with renal stones? (5)
Signs of UTI Signs of renal failure Refractory pain despite analgesia Bilateral obstructing stones If the patient is elderly, a child or otherwise unwell (e.g. unable to tolerate oral fluids) for closer monitoring
What is the Mx acutely for someone presenting with renal colic?
Paracetamol
NSAIDs
^preferred to opiates
Encourage fluid intake
Why are opiates not first choice for renal colic?
Studies show they provide equally adequate analgesia in the context of kidney stones, may have some additional effect of decreasing ureteric smooth muscle tone, and lack some of the adverse effects of opiates, notably respiratory and central nervous system (CNS) depression, vomiting, and disorientation.
What does the Mx of urinary stones depend upon
Whether big or smaller than 0.5cm in diameter, and whether or not it has passed within 4-6 weeks
Mx of urinary stones less than 0.5cm in size
1) Stones <0.5 cm diameter
− Start with a trial of conservative management (analgesia and encourage
oral fluid intake). Ninety per cent of stones <0.5 cm pass spontaneously, although only 10% of larger stones do. Patients should be asked to strain their urine to recover the stone for analysis.
− You may consider adding medication to relax the smooth muscle of the ureter, either an α-blocker (e.g. tamsulosin) or a calcium-channel blocker (e.g. nifedipine).
Follow up patients after 2–3 weeks and request a plain KUB radiograph to
minimize the radiation exposure of repeat CT-KUB.
Mx of urinary stones more than 0.5cm in size (5)
− Lithotripsy, otherwise known as extracorporeal shock wave lithotripsy
(ESWL) if small enough (renal stones <2 cm, ureteric stones <1 cm).
− Ureterorenoscopic removal (using a fine telescope inserted via the ure- thra) with a dormia basket, holmium laser, mechanical lithotripsy etc., if too large for ESWL. Note that this commonly requires a post-operative
ureteric stent as it can cause ureteric stricture.
− Percutaneous nephrolithotomy (PCNL) is rarely used nowadays as it is
invasive and thus there are risks of bleeding and damage to the collecting
system and neighbouring structures.
− Stenting (using a JJ stent) or percutaneous nephrostomy may be performed
in order to prevent hydronephrosis, if the obstruction cannot be resolved
surgically.
− Antibiotic cover if an invasive procedure is employed.
What should all Px with renal stones be advised?
To increase their fluid intake
What is the most common causative organism in acute pyelonephritis?
E coli
Why must pyelonephritis be dealt with swiftly?
Can proceed to septicaemia very quickly
Mx of acute pyelonephritis (7)
IV fluids if hypotensive ABx for 2 weeks Analgesia Monitor renal function and urine output Maintain a high suspicion for intrarenal or perinephric abscess
Medical conditions that can predisposed stones (12)
• Metabolic:
− Hypercalciuria
− Hyperuricosuria
− Hypocitraturia
− Hyperoxaluria
− Gout and other hyperuricaemic states e.g. malignancy, glucose-6-phosphate dehydrogenase
(G6PDH) deficiency (urate stones)
− Cystinuria
• Primary hyperparathyroidism
• Crohn’s disease (often oxalate stones, although the exact mechanism for this remains unclear)
• Chronic UTI due to urease-producing bacteria (struvite stones)
• Medullary sponge or polycystic kidneys (resulting in static collections in which stones form)
• Renal tubular acidosis (stones result from hypercalciuria, alkalinization of the urine causing precipita- tion of calcium phosphate, and low urinary citrate)
• Sarcoidosis (causes a hypercalcaemia that can lead to stone formation
What radiographical findings would you look for in a patient with suspected kidney stones? (3)
- The stones themselves
- Hydronephrosis and/or hydroureter (dilated ureters) due to obstruction
- Perinephric fluid
What are the complications of kidney stones? (6)
Ureteric stricture Acute or chronic pyelonephritis Renal failure Intrarenal or perinephric abscess Xanthogranulomatous pyelonephritis Urine extravasation
Contraindications of NSAIDs (4)
- Asthma
- History of anaphylaxis with any NSAID
- Previous or active peptic ulcers
- Severe heart failure
Contraindications of COX-2 selective inhibitors - form of NSAID (3)
Should not be used in ischaemic heart disease, cerebro- vascular disease, or peripheral arterial disease as they are associated with an increased risk of throm- botic events
When should NSAID’s be used with caution (7)
- Coagulation defects: may be exacerbated due to antiplatelet effects.
- Renal, cardiac, or hepatic impairment: NSAIDs may impair renal function and cause fluid retention, lead- ing to pulmonary oedema in patients with cardiac failure. This is more likely to occur if the patient has poor liver function (hepatic impairment) or pre-existing kidney disease (renal impairment).
- During pregnancy and breast-feeding: closure of the ductus arteriosus can occur in response to NSAIDs and this is a problem if it occurs in utero. There may also be delayed onset and increased duration of labour. NSAIDs are sometimes found in breast milk but there is little information on the risks presented. Nonetheless most manufacturers advise avoiding them if breast-feeding.
- The elderly: as the risk of bleeding is more common and is more likely to have a serious outcome.
What are the red flag symptoms of back pain? (2 immediate referral, 5 within 1 week, 4 ASAP)
Sphincter problems
Patient unable to self-care or walk
Weight loss Fever Back tenderness to palpation Thoracic spinal pain Violent trauma
Age <20 years or >50 years
Severe morning stiffness
Structural deformity (e.g. scoliosis)
Nerve root pain not resolving >6 weeks
