Nephrology Flashcards
is a severe, chronic, inflammatory disorder of the skin characterized by painful sloughing ulceration with a purulent or vegetative base and an elevated dusky blue or reddish-purple undermined border surrounded by a rim of inflammation.
Pyoderma gangrenosum
a paraneoplastic disorder associated with renal cell cancer
typically presents as cholestasis/hepatosplenomegaly
it is thought to be secondary to increased levels of IL-6
Stauffer syndrome
In AKI, hyperkalaeamia which is refractory to medical management is an indicator for renal replacement therapy
ADPKD is associated with
Mitral valve prolaspe
aortic root dilation
Extra-renal manifestations
liver cysts (70% - the commonest extra-renal manifestation): may cause hepatomegaly
berry aneurysms (8%): rupture can cause subarachnoid haemorrhage
cardiovascular system: mitral valve prolapse, mitral/tricuspid incompetence, aortic root dilation, aortic dissection
cysts in other organs: pancreas, spleen; very rarely: thyroid, oesophagus, ovary
Contrast media nephrotoxicity may be defined as a 25% increase in creatinine occurring within 3 days of the intravascular administration of contrast media.
Contrast-induced nephropathy occurs***** after administration.
2 -5 days
Fusion of podocytes and effacement of foot processes is an electron microscopy finding in
minimal change disease
HIV-associated nephropathy (HIVAN) causes collapsing FSGS and usually presents as nephrotic syndrome
It manifests as rapidly advancing nephrotic syndrome. Ultrasound shows large echogenic kidneys. Light microscopy most commonly shows a pattern of collapsing focal segmental glomerulosclerosis (FSGS) which often shows marked focal or global collapse of the basement membrane associated with hypertrophy and hyperplasia of the overlying podocytes. Therefore, podocyte proliferation with marked focal collapse of the glomerular basement membrane is correct.
Mesangial hypercellularity with positive immunofluorescence for IgA & C3 is a finding in
IgA nephropathy
Subendothelial and mesangial immune deposits resulting in a ‘tram-track’ appearance is an electron microscopy finding seen in
type 1 membranoproliferative glomerulonephritis which is associated with hepatitis C.
HIV-associated nephropathy (HIVAN) causes collapsing FSGS and usually presents as nephrotic syndrome
Thickened basement membrane with subepithelial electron-dense deposits creating a ‘spike and dome’ appearance is an electron microscopy finding associated with
membranous glomerulonephritis.
Renal involvement in HIV patients may occur as a consequence of treatment or the virus itself. Protease inhibitors such as **** can precipitate intratubular crystal obstruction.
indinavir
0.9% saline
if large volumes are used there is an increased risk of
hyperchloraemic metabolic acidosis
Spontaneous coronary artery dissection (SCAD) is defined by an abrupt separation within the layers of the coronary artery wall, which may precipitate myocardial infarction. SCAD is typically linked to heritable connective tissue disorders like Ehlers-Danlos syndrome and Marfan syndrome but has no established link to ADPKD.
SLE Lupus nephritis not responding to steroids
A large body of evidence from the use of azathioprine in pregnancy for the treatment of both rheumatological conditions and inflammatory bowel disease, supports its use. Although it is less effective in the management of SLE with renal disease versus other options, balance of benefit risk makes it the preferred intervention.
Ciclosporin appears to be associated with premature delivery and low birth weight, although it does not seem to be associated with malformations, this drives its use as an alternative to azathioprine in patients who fail to gain control of their disease. Cyclophosphamide, methotrexate and mycophenolate are all contraindicated for use in pregnancy.
Metabolic acidosis is commonly classified according to the anion gap. This can be calculated by: (Na+ + K+) - (Cl- + HCO-3). If a question supplies the chloride level then this is often a clue that the anion gap should be calculated.
The normal range = 10-18 mmol/L
*** is an antibody used in the treatment of hypercalcaemia associated with malignancy.
Denosumab
A high-arched palate is associated with a number of congenital conditions, particularly those affecting the connective tissues such as
Marfan and Ehlers-Danlos syndrome
Primary HUS (‘atypical’) is due to
complement dysregulation
Most cases are secondary (termed ‘typical HUS’):
classically Shiga toxin-producing Escherichia coli (STEC) 0157:H7
‘
verotoxigenic’, ‘enterohaemorrhagic’
this is the most common cause in children, accounting for over 90% of cases
pneumococcal infection
HIV
rare: systemic lupus erythematosus, drugs, cancer
Exposure to Aflatoxin, a mycotoxin produced by the fungi Aspergillus flavus and Aspergillus parasiticus, has been strongly associated with*****
liver cancer
This parasitic infection primarily affects the intestines and can cause abdominal pain, diarrhoea, and rash. In severe cases or in immunocompromised individuals, it can lead to hyperinfection syndrome or disseminated disease affecting multiple organs
Strongyloides stercoralis infection
when HLA matching for a renal transplant the relative importance of the HLA antigens are as follows
DR > B > A
is a selective androgen synthesis inhibitor that works by blocking cytochrome P450 17 alpha-hydroxylase. It blocks androgen production in the testes and adrenal glands, and in prostatic tumour tissue.
Abiraterone acetate
non-steroidal anti-androgen
blocks the androgen receptor
bicalutamide
androgen synthesis inhibitor
option for the treatment of hormone-relapsed metastatic prostate cancer in patients who have no or mild symptoms after androgen deprivation therapy has failed, and before chemotherapy is indicated
abiraterone
V1 receptors are found on vascular smooth muscle and when activated cause vasoconstriction. V3 receptors are expressed in the pituitary gland and modulate ACTH secretion.
Tolvaptan blocks the action of vasopressin at the V2 receptor. This receptor is found on the basolateral membrane of the principal cells in the collecting ducts of the kidney. This reduces water absorption (through decreased aquaporin 2) and increases aquaresis without sodium loss.
Desmopressin is a synthetic analogue of vasopressin that exerts agonism at the V2 receptor.
Complications of plasma exchange
hypocalcaemia: due to the presence of citrate used as an anticoagulant for the extracorporeal system
metabolic alkalosis
removal of systemic medications
coagulation factor depletion
immunoglobulin depletion
***, (also known as struvite), kidney stones are formed by urea-splitting bacteria, of which Proteus is an example.
Magnesium ammonium phosphate stones can form very large calculi known as staghorn calculi which may significantly impact on renal function due to chronic obstruction and failure to clear urinary tract infection adequately. Treatment of the underlying urinary tract infection, coupled with a urology consult to assess the need for removal of any larger stones are the cornerstone of management.
Calcium phosphate renal stones are associated with hyperparathyroidism, and urate stones are associated with gout. Cystine stones are seen in patients with inherited cystinuria, and oxalate stones are primarily associated with short bowel syndrome.
this organism typically presents with more severe clinical manifestations like necrotizing fasciitis or streptococcal toxic shock syndrome.
Streptococcus pyogenes
Streptococcus agalactiae, also known as
Group B Streptococcus (GBS),
Rx for PD associated peritonitis
the BNF recommends vancomycin (or teicoplanin) + ceftazidime added to dialysis fluid OR vancomycin added to dialysis fluid + ciprofloxacin by mouth
aminoglycosides are sometimes used to cover the Gram negative organisms instead of ceftazidime
*** describes the proliferation of cells in the walls of the arteries causing the vessels to bulge or narrow. This most commonly affects women. These patients are susceptible to AKI after the initiation of an ACE inhibitor. The classic description is ‘string of beads’ appearance
Fibromuscular dysplasia
**** manifests as membranoproliferative glomerulonephritis (MPGN) or a diffuse proliferative glomerulonephritis rather than membranous glomerulonephritis.they are immunoglobulins that precipitate at low temperatures and can deposit in small vessels, leading to vasculitis and glomerular injury
Cryoglobulinemia
CKD stage 1 . This would be the case if there was supporting evidence of kidney damage but an eGFR > 90ml/minute.
CKD stage 2 . This would be the case if there was supporting evidence of kidney damage and an eGFR between 60 and 90ml/minute.
CKD stage 3a . This would be the case if eGFR was 45-59 ml/min, irrespective of other evidence of kidney damage.
CKD stage 4 . This would be the case if the eGFR was 15-29 ml/min, irrespective of other evidence of kidney damage.
CKD stage GFR range
1 Greater than 90 ml/min, with some sign of kidney damage on other tests (if all the kidney tests* are normal, there is no CKD)
2 60-90 ml/min with some sign of kidney damage (if kidney tests* are normal, there is no CKD)
3a 45-59 ml/min, a moderate reduction in kidney function
3b 30-44 ml/min, a moderate reduction in kidney function
4 15-29 ml/min, a severe reduction in kidney function
5 Less than 15 ml/min, established kidney failure - dialysis or a kidney transplant may be needed
***** plays a role in preventing iron absorption by blocking the action of ferroportin, a transmembrane protein that maintains iron homeostasis. Due to increased levels of this in CKD, iron absorption is pathologically reduced, leading to iron-deficiency anaemia.
Hepcidin
Hepcidin is an acute-phase reactant that is often increased in CKD due to inflammation and reduced renal clearance.
***is the most common and important viral infection in solid organ transplant recipients
Cytomegalovirus
Metabolic acidosis, leads to anaemia in CKD
This is because metabolic acidosis (common in CKD) inhibits the conversion of ferric iron (Fe 3+) to its absorbable form, ferrous iron (Fe 2+), in the duodenum, resulting in reduced absorption.
Chromosome 12 - hypochondroplasia, and colorectal cancer
Chromosome 8 - Burkitts lymphoma
Chromosome 20 - Alagille syndrome and Creutzfeldt-Jakob disease.
Tubular re absorption
PCT- presentation of increased urinary glucose and phosphate and a decrease in potassium levels combined with growth retardation and muscle weakness strongly suggest Fanconi syndrome. and decreased serum Bicarbonate
DLOH - Water re absorbed through osmosis
ALOH - significant role in the absorption of sodium, chloride, and potassium ions, it can contribute to the resorption of magnesium and calcium ions
Water and sodium reabsorption occur within the collecting duct.
Reabsorption of sodium and chloride occurs in the distal convoluted tubule across its apical membrane
describes a generalised reabsorptive disorder of renal tubular transport in the proximal convoluted tubule resulting in:
type 2 (proximal) renal tubular acidosis
polyuria
aminoaciduria
glycosuria
phosphaturia
osteomalacia
Fanconis syndrome
Causes
cystinosis (most common cause in children)
Sjogren’s syndrome
multiple myeloma
nephrotic syndrome
Wilson’s disease
Ureteric obstruction due to stones together with infection is a surgical emergency and the system must be decompressed.
Options include nephrostomy tube placement, insertion of ureteric catheters and ureteric stent placement.
More intensive and urgent treatment is indicated in the presence of ureteric obstruction, renal developmental abnormality such as horseshoe kidney and previous renal transplant.
Drugs causing ACUTE INTERSTITIAL NEPHRITIS
Causes
drugs: the most common cause, particularly antibiotics
penicillin
rifampicin
NSAIDs
allopurinol
furosemide
systemic disease: SLE, sarcoidosis, and Sjogren’s syndrome
infection: Hanta virus , staphylococci
CKD on haemodialysis - most likely cause of death is
IHD
Spironolactone is an aldosterone antagonist which acts in the***
cortical collecting duct.
RALES
NYHA III + IV, patients already taking ACE inhibitor
low dose spironolactone reduces all cause mortality
By administering exogenous****, we can correct the anaemia, which leads to improved oxygen delivery to tissues. This results in better exercise tolerance, reduced fatigue, and improved quality of life for patients.
EPO
Patients who have received an organ transplant are at risk of skin cancer (particularly****) due to long-term use of immunosuppressants
squamous cell carcinoma
A gain of function mutation affecting epithelial Na channels occurs in*****. In Liddle syndrome, excessive sodium reabsorption from the collecting tubule leads to hypertension and also creates a negative potential within the collecting tubule that traps hydrogen and potassium ions, leading to metabolic alkalosis and hypokalaemia.
Liddle syndrome
mutation affecting the reabsorption of sodium/chloride at the distal convoluted tubule (DCT) is responsible for**. These patients experience metabolic alkalosis and hypokalaemia (due to a rise in aldosterone, secondary to sodium loss), hypomagnesaemia, hyponatraemia and hypercalcaemia (due to increased calcium reabsorption). This condition is analogous to long-term thiazide diuretic use.
Gitelman syndrome
A mutation affecting the reabsorption of sodium/potassium/chloride ions in the thick ascending loop of Henle is responsible for****. These patients experience metabolic alkalosis and hypokalaemia (due to a rise in aldosterone, secondary to sodium loss) and hypercalciuria. This condition is analogous to long-term loop diuretic use.
Bartter syndrome
MDMA (Ecstasy) abuse can cause**** and the phenomenon is well described in adults.
SIADH
Alcohol bingeing can lead to **** in the posterior pituitary gland subsequently leading to polyuria
ADH suppression
** is a group of signs/symptoms indicative of liver dysfunction arising due to underlying renal cell carcinoma. Biochemically, there is can be an elevated alkaline phosphatase (ALP), γ-glutamyl transferase (GGT), platelets; prolonged prothrombin time (PT) with hepatosplenomegaly without hepatic metastasis or jaundice.
Stauffer’s syndrome
The*** which affects the ADH receptor in the distal convoluted tubule and collecting ducts is the more common genetic mutation which causes congenital nephrogenic diabetes insipidus (74.7% of cases). The V2R gene mutation which affects the ADH receptor in the distal convoluted tubule and collecting ducts is the more common genetic mutation which causes congenital nephrogenic diabetes insipidus (74.7% of cases).
V2R gene mutation
A mutation in the Wolframin gene would cause DIDMOAD or Wolfram syndrome, another cause of****
cranial diabetes insipidus.
Renal stones on x-ray
cystine stones: semi-opaque
urate + xanthine stones: radio-lucent
struvite or magnesium ammonium phosphate stones, are associated with urinary tract infections caused by urease-producing bacteria such as Proteus, Klebsiella, and Pseudomonas species. They are fully radiopaque on X-ray due to their mineral content and often form large staghorn calculi that fill the renal pelvis and calyces. They appear distinctly white on X-ray rather than semi-opaque.
drugs that promote calcium stones: loop diuretics, steroids, acetazolamide, theophylline
Prevent - thiazide diuretics
Risk factors for urate stones
gout
ileostomy: loss of bicarbonate and fluid results in acidic urine, causing the precipitation of uric acid
Rapidly progressive glomerulonephritis, causes:
Goodpasture’s
ANCA positive vasculitis
Anti-Mi-2 antibodies are specific for
dermatomyositis. This presents with rashes and proximal muscle weakness,
Calcium resonium results in removal of potassium from the body,
It increases potassium excretion by preventing enteral absorption
Young female, hypertension and asymmetric kidneys →
fibromuscular dysplasia
****, is a metabolic disorder that can lead to thromboembolic events due to increased levels of homocysteine. It can also cause ocular abnormalities, skeletal abnormalities like osteoporosis and marfanoid habitus, and cognitive impairment.
Homocystinuria
Epididym-orchitis Rx if STI
IM ceftriaxone stat + oral doxycycline for 2 weeks.
if enteric organisms are the most likely cause
send an MSU as above
treating empirically with an oral quinolone for 2 weeks (e.g. ofloxacin)
IgA Nephropathy
Prognosis
25% of patients develop ESRF
markers of good prognosis: frank haematuria
markers of poor prognosis: male gender, proteinuria (especially > 2 g/day), hypertension, smoking, hyperlipidaemia, ACE genotype DD
Antiretroviral therapy is the treatment of choice. If a patient is already taking antiretroviral therapy (which should be all HIV-diagnosed patients) adherence should be checked.
HIVAN
diseases would give a positive cyanide-nitroprusside test?
Cystinuria, Homocystinuria
Flash pulmonary oedema, U&Es worse on ACE inhibitor, asymmetrical kidneys → renal artery stenosis - Ix of choice?
do MR angiography
combination of hypercoagulability, sudden-onset unilateral flank pain, acute deterioration in renal function and new haematuria point towards the unifying diagnosis of****
renal vein thrombosis
Nephrotic syndrome is associated with a hypercoagulable state due to loss of antithrombin III via the kidneys
Nephrotic syndrome is associated with hypercoagulability, due to loss of antithrombin III through an excessively permeable glomerular filtration barrier. This makes patients susceptible to venous thromboembolism. In this scenario, the combination of hypercoagulability, sudden-onset unilateral flank pain, acute deterioration in renal function and new haematuria point towards the unifying diagnosis of renal vein thrombosis.
Tumour markers
germ cell tumours
seminomas: seminomas: hCG may be elevated in around 20%
non-seminomas: AFP and/or beta-hCG are elevated in 80-85%
LDH is elevated in around 40% of germ cell tumours
Use of 0.9% Sodium Chloride for fluid therapy in patients requiring large volumes =
risk of hyperchloraemic metabolic acidosis
When prescribing for routine maintenance alone, consider using 25-30 ml/kg/day sodium chloride 0.18% in 4% glucose with 27 mmol/l potassium on day 1 (there are other regimens to achieve this).
The classic tetrad of symptoms in HSP
non-thrombocytopenic palpable purpura, arthritis or arthralgia, abdominal pain and renal disease. Thrombocytopenia is not typically associated with HSP.
Non blanching rash
HSP
Meningococcal septicaemia
Immune thrombocytopenic purpura
HUS
**** (a C5 inhibitor monoclonal antibody) has evidence of greater efficiency than plasma exchange alone in the treatment of adult atypical HUS
eculizumab
The time taken for an arteriovenous fistula to develop is
6 to 8 weeks
In VUR , chronic can produce renal scar leading to increased quantities of renin causing hypertension
Serum C4 is the most reliable and widely used screening tool
Hereditary angioedema
