RANDOM Flashcards
Three recommended reasons for referral for further investigation of atherosclerotic renal artery stenosis?
- Refractory hypertension (BP >150/90 mmHg despite 3 antihypertensives)
- Recurrent episodes of pulmonary oedema despite normal left ventricular function
- Rise of >20% serum creatinine or fall of GFR >15% over 12 months with high clinical suspicion of widespread atherosclerosis, or during the first 2 months after initiation with an ACE inhibitor or angiotensin receptor blocker.
STATS: how to use sensitivity and specificity?
High sensitivity helps to rule out disease (SnOut) and a high specificity helps to rule in (SpIn) disease
What is T4 RTA?
Type 4 renal tubular acidosis is caused by hypoaldoseteronism, resulting in reduction in proximal tubular ammonium excretion.
What causes t4 rta?
Type 4 renal tubular acidosis is not a tubular disorder at all, but is included in the classification as it is associated with a mild (normal anion gap) metabolic acidosis due to a physiological reduction in proximal tubular ammonium excretion. The underlying cause of this is hypoaldoseteronism, due to either:
primary deficiency
hyporeninaemic hypoaldosteronism, or
aldosterone resistance (caused by eplerenone, spironolactone, trimethoprim, pentamidine, or pseudohypoaldosteronism).
Biochemical features of T4 RTA?
It can also be caused by collecting duct dysfunction from renal insufficiency. The cardinal feature is hyperkalaemia and normal urinary acidification.
Sodium wasting is a variable feature of type 4 renal tubular acidosis, as aldosterone normally enhances sodium reabsorption. It is not usually as marked as in this case, but it is possible the diuretic has exacerbated it.
Which enzyme is the target of the antibodies found in primary biliary cirrhosis?
Pyruvate dehydrogenase (PD)
What does pyruvate dehydrogenase (PD) do?
generates pyruvate from phosphoenolpyruvate
Pyruvate dehydrogenase (PD), required for the generation of acetyl-CoA from pyruvate for entry into the tricarboxylic acid (TCA) cycle, is found in the mitochondria.
Anti-mitochondrial antibodies (AMAs), the serological hallmark of primary biliary cirrhosis (PBC), are often targeted against pyruvate dehydrogenase.
Pompe’s disease is a deficiency of what?
alpha-glucosidase
and is also known a*s glycogen storage disease *type 2.
Pompe’s disease: symptoms
Myopathy
Restrictive cardiomyopathy
Hepatomegaly
can be treated with supplementation of the enzyme.
What is Achondroplasia ?
- Autosomal dominant condition
- commonest forms of short-limbed dwarfism
- Caused by an activated point-mutation of the fibroblast growth factor receptor 3 (at 4p16.3).
Achondroplasia -incidence increases with?
Increasing paternal age
Ulnar neuropathy causes?
(3)
- ring and little finger paraesthesia
- hypothenar wasting
- weak thumb adduction
What is typically elevated in Gaucher’s disease?
acid phosphatase
What is typically reduced in Gaucher’s disease?
glucocerebrosidase
What causes psuedohypoparathyroidism
Mutation of the PTH receptor with abnormality of the Gs alpha subunit with reduced cyclic adenosine monophosphate (cAMP) production
Clinical features of TTP?
microangiopathic haemolytic anaemia
acute kidney injury
thrombocytopenia
fever and
neurological symptoms
eculizumab MoA and use
(a C5 inhibitor monoclonal antibody)
adult atypical HUS
A L5/S1 disc prolapse affects the S1 nerve root causing:
Sensory loss to the posterior calf and the plantar surface of the foot
Motor loss to gastrocnemius and soleus, and
Loss of ankle jerk
L3/4 disc prolapse affects the L4 nerve root, causing:
Pain in the anterior thigh
Quadriceps weakness
Reduced knee jerk
Loss of sensation over the thigh
L4/5 disc prolapse affects the L5 nerve root, causing:
Pain over lateral aspect of thigh and leg
Loss of sensation to lateral aspect of leg and dorsum of foot
Weakness of dorsiflexion (‘foot drop’)
Reflexes often unaffected
Primary hyperaldosteronism features?
High aldosterone
suppressed renin
alkalosis
low potassium
low magnesium
and normal/high sodium.
P450 dependent drugs
- Warfarin
- Estrogen
- Phenytoin
- Theophylline
- Digoxin
P450 inhibitors
- Acute alcohol intake
- Allopurinol
- Amiodarone
- Cimetidine, omeprazole
- Dapsone
- Imidazoles: ketoconazole, fluconazole
- INH
- Macrolides (Azithro-Clarithro-Erythro mycins)
- Quinolones (ciprofloxacin)
- Quinupristin
- Sodium valproate
- Spironolactones
- SSRIs: fluoxetine, sertraline
- Grapefruit juice (potent inhibitor of the cytochrome P450 enzyme CYP3A4)
- Protease inhibitors (ndinavir, nelfinavir, ritonavir, saquinavir)
P450 inducers
- Antiepileptics: phenytoin, carbamazepine (note that valporate is an inhibitor)
- Barbiturates
- Chronic alcohol intake
- Griseofulvin
- Quinidine
- Rifampicin
- Smoking (affects CYP1A2, reason why smokers require more aminophylline)
- St John’s Wort
- Sulfa drugs
- Tetracycline
- Nevirapine (NNRTI)
Which drugs can be cleared by HD
- Barbiturate
- Lithium
- Alcohol (inc methanol, ethylene glycol)
- Salicylates
- Theophyllines (charcoal hemoperfusion is
preferable)
Drugs impairing glycaemia
- Thiazides, furosemide (less common)
- Steroids
- Tacrolimus, cyclosporin
- Interferon-α
- Nicotinic acid (vitamin B3)
