KSAP May 2019 Flashcards
What is the typical mechanism of hypokalaemia with posaconazole?
Apparent mineralocorticoid excess; AME presents with hypertension, hypokalemia, metabolic alkalosis, and suppressed levels of renin and aldosterone. AME in this instance is secondary to inhibition of 11 β-hydroxysteroid dehydrogenase type 2 by posaconazole.
How does licorice cause hypokalaemia?
AME; inhibition of 11 β-hydroxysteroid dehydrogenase type 2
What is the normal ratio of cortisol to cortisone if 11 beta hydroxysteroid dehydrogenase is working well?
Ratio of cortisol-to-cortisone is approximately 0.3–0.5
What is the cause of Liddle syndrome?
Autosomal dominant gain of function mutation in the ENaC.
What is the metabolic abnormality associated with neobladder formation?
NAGMA; the bowel segment actively reabsorbs NH4+ and Cl-, while secreting Na+ and HCO3-.
What type of metabolic abnormality is associated with Short Gut Syndrome?
AGMA; d-lactic acidosis
How do silicone implants cause hypercalcaemia?
Granulomatous inflammation induced by the silicone implants leading to overproduction of 1,25-(OH)2 vitamin D3 (calcitriol) is the most likely cause of hypercalcemia, hypercalciuria, and recurrent kidney stones.
Can DKA cause a NAGMA?
Yes, if renal function is preserved, NAGMA may occur due to the rapid filtration and excretion of the keto-acid.
What type of RTA is associated with topiramate?
pRTA
What is the difference between CSW and SIADH?
Patients with CSW are judged to be hypovolaemic
What type of RTA is Rheumatoid Arthritis associated with?
dRTA
What are the criteria for combined liver kidney transplant?
AKI criteria: eGFR ≤ 25ml/min OR on dialysis for 6 consecutive weeks
CKD criteria: eGFR ≤60ml/min for at least 90 days and ≤30ml/min at the time of listing OR on dialysis
Metabolic indications (i.e. primary oxaluria, aHUS)
What is the value of the hepatic venous pressure gradient?
HVPG <10mmHg are only at 10% risk of decompensation episode in 4 year period. The value is in helping decide who needs dual liver and kidney versus kidney alone.
Why is significant hypokalaemia not associated with norepinephrine?
It activates the B1 receptors, preferentially
How does hypothermia cause hypokalaemia?
- Cold induced diuresis
2. Endogenous release of epinephrine (stimulation of B2 receptors) which leads to an intracellular shift
What are the signs of imminent AVF rupture?
- Shiny skin
2. Can’t pinch skin over aneurysm
What features might help you distinguish SIADH from CSW?
- CSW = hypovolaemic
- FE Ua disappears in SIADH but persists in CSW
- High FE phos in CSW
- Decrease in Uosm after an infusion of NaCl suggest CSW
What blood type has less surface antigen expression: A1 or A2?
A2… if a anti-B patient has low anti-A titres, donation from A2 is possible
What factors have a negative impact on fistula maturation?
- Diabetes mellitus
- Female sex
- Peripheral arterial disease
What is the diameter cutoff for veins that suggests patency of a fistula is more likely?
2.5mm
What is the rate of Central Venous Stenosis with Tunnelled Dialysis Catheters?
10-15%
What would you expect urinary chloride to be like in Bartter’s and Gitelman’s?
High urinary chloride
What features in ADPKD are predictive of progressive disease?
- First urological event before the age of 35
- Truncating PKD1
- Hypertension
- Male sex
Also consider imaging (Mayo Imaging Calculator) Age, height, and total kidney volume… >1000ml and >17cm kidney length
What was the main finding of the HALT PKD study?
Intensive blood pressure control limited kidney volume increase and left ventricular mass and urine albumin excretion
What type of stone is associated with zonisamide?
Calcium phosphate
Where is CA II and IV found?
II in the PCT and IV in DCT
What is the genetic cause of ARPKD?
A mutation in the PKHD1 gene. This encodes fibrocystin and polyductin.
What are the features of ARPKD?
- Microcysts in the kidney within the cortex and the medulla
- Enlarged left lobe of liver
- Intrahepatic ductal dilation and portal hypertension
What percentage of patients present in early adulthood with ARPKD?
25-30%;
What is the phenotype of VHL syndrome?
Mutation in VHL suppressor gene; kidney function is normal but increased risk of renal cancers, assoc with cerebellar haemangioblastoma, pancreatic cyst adenoma, and phaeo.
What is more tubulotoxic, ifosfamide or cyclophosphamide?
Ifosfamide
What is the mechanism by which methotrexate causes AKI?
Crystallopathy
When can HbA1c be used post-transplant?
12 weeks post-operative
How would you confirm a diagnosis of urinary leak post transplant?
- demonstration of contrast extravasation on cystogram or antegrade nephrostogram, or by radioactive tracer accumulation outside the collecting system and bladder on nuclear medicine scanning.
What is the cause of urine leak?
The most frequent causes include trauma to the ureter during dissection or ischemia of the distal ureter resulting in necrosis or acute rejection.
What are the causes for chyloperitoneum?
- trauma,
- malignancy,
- primary lymphatic obstruction,
- radiation,
- pancreatitis,
- sarcoidosis, and
- medication adverse effect (most commonly seen with calcium channel blockers)
What are the Banff criteria for chronic active AMR?
- Evidence of chronic tissue injury including transplant glomerulopathy
- Evidence of current or recent antibody interaction with vascular endothelium including C4d staining in the peritubular capillaries, microvascular inflammation including glomerulitis and peritubular capillaritis, or increased expression of gene transcripts associated with AMR
- Presence of HLA or non-HLA DSAs
What is the mechanism for hyperkalaemia with urinary retention?
- a defect in sodium absorption in the cortical collecting duct (CCD), resulting in impairment in generating a lumen-negative electrical potential with consequent defective hydrogen and potassium secretion (voltage defect).
- Another proposed mechanism is a generalized defect in hydrogen and potassium secretion due to obstructive damage to the CCD.
What is the net effect of the causative mutations in Gordon syndrome?
Mutations result in upregulation the sodium/chloride (NC) and sodium/potassium/chloride (NKCC) transporters and downregulation the renal outer medullary potassium channel (ROMK), causing hyperkalemia, hyperchloremic metabolic acidosis, volume overload, and resistant hypertension.
What was the principle finding of the CORAL study?
- The Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) trial was the largest study of renal artery stenting.
- This study found that the addition of renal artery stenting to medical management provided no benefit for the primary composite end point of death, myocardial infarction, stroke, hospitalization for congestive heart failure, progressive renal failure, or need for renal replacement therapy.
How would you define resistant hypertension?
Resistant hypertension is defined as BP above goal despite the use of 3 antihypertensive agents of different classes at appropriate doses, at least one of which is a diuretic
What is the evidence for STS in calciphylaxis?
Although there are no randomized controlled trials demonstrating the effectiveness of sodium thiosulfate, observational studies have shown complete remission of calciphylaxis lesions in 26–52% of patients.
What are the adverse effects of STS?
- nausea and vomiting,
- volume overload, and
- an anion gap metabolic acidosis (accumulation of thiosulfate)
What are the indications for dialysis with salicylate toxicity?
- Markedly elevated serum concentrations of salicylate (>100 mg/dL),
- central nervous system dysfunction,
- renal failure limiting the ability to alkalinize the urine,
- severe metabolic acidosis, and
- pulmonary edema/hypoxia
What is the goal for arterial pH with peripheral alkalisation in salicylate poisoning?
- Aim for an arterial pH of 7.5-7.6
What are the “boards” clinical features of an air embolism?
- Foam in the venous blood line may suggest the diagnosis.
- a continuous, churning cardiac murmur may be present.
What are the features of CMV disease?
- colitis,
- pneumonitis, and
- retinitis
What is the cause of gestational diabetes insipidus?
Gestational DI is a rare form of DI that occurs when ADH is synthesized and released normally but is degraded by placental vasopressinase, preventing it from reaching its site of action at the collecting tubule.
What is the treatment of GDI?
Desmopressin (resistant to vasopressinase)
How would you differentiate CDI from GDI?
- response to exogenous vasopressin. In GDI, the absence of improvement in polyuria after vasopressin excludes central DI.
Why might a skin biopsy not be useful in the diagnosis of Alport’s disease?
- the dermal basement membrane contains type IV α-5 collagen, skin biopsy may be diagnostic in cases of X-linked COL4A5 mutations but is not useful in cases due to COL4A3/4 mutations.
What are the features of a Vv infection?
- gastroenteritis,
- primary sepsis with bacteremia, and
- necrotizing soft tissue infections
In what scenarios might you still perform stenting of ARAS?
- worsening or uncontrolled hypertension,
- progressive loss of kidney function without other cause (>50% within 12 months),
- decompensated heart failure, or recurrent pulmonary edema
