Chem path Flashcards
feature of hypercalcaemia
bone (fractures)
moans (depression)
groans (abdo pain)
stones (kidney stones)
features of hypocalcaemia
neuromuscular excitability leading to fits
colle’s fracture
posterior displacement of the wrist resulting into a fracture
causes of a colle’s fracture
falling onto an extended hand
smith’s fracture
anterior displacement of the wrist
causes of a smith’s fracture
falling onto a flexed hand
Pott’s fracture
fracture of the tibia and fibula
ANKLE FRACTURE
best investigation for suspected renal stones
abdo XRAY
first blood test to do when renal stones detected on xray
serum calcium
differential diagnosis of a raised calcium
1) cancer
2) hyperparathyroidism
3) sarcoid
what does a normal PTH with a high calcium mean
PRIMARY HYPERPARATHYROIDISM
how do you differentiate between the three differentials for high calcium
differentials (cancer, primary hyperparathyroidism, sarcoid)
test: PTH
how does PTH increase serum calcium
increased absorption in the SI
increased release of calcium from bones
reduced calcium excretion in urine
where does 1 alpha hydroxylase act
liver
where does 1,25 hydroxylase act
kidney
which enzyme does PTH regulate
25 hydroxylase
eye sign of hypercalcaemia
band keratopathy
complications of hypercalcaemia
osteofibrosis cystica pepper pot skull polydipsia peptic ulcer disease pancreatitis
how does hypercalcaemia cause polydipsia
calcium is an osmotic diuretic
MEN1 complications
parathyroid hyperplasia
pituitary adenoma
pancreatic tumours
MEN2 complications
parthyroid hyperplasia
pheochromocytoma
medullary thyroid carcinoma
how to treat hypercalcaemia
FLUIDS FLUIDS FLUIDS
SALINE
how to cure the hypercalcaemia due to primary hyperparathyroidism
parathyroidectomy
what do you give with the IV saline in the treatment of hypercalcaemia
frusemide (loop diuretic)
which diuretic must be avoided in hypercalcaemic patients
thiazides
why can you normally detect intracellular enzyme in the plasma
due to increased cell turnover
what can cause increased plasma enzyme levels
tissue injury or cell breakdown
what order are cardiac enzymes released in
myoglobin (cytosolic)
CK (nucleus and mitochondria)
troponin (contractile apparatus)
what is special about order of troponin release
some troponin is in the cytoplasm and so there is an initial small rise. However most is in the contractile apparatus and is released later causing the sustained late rise
causes of raised enzyme levels
increased synthesis
reduced clearance
where is ALP made
bone
liver
placenta
intestine
what is an isoenzyme
an enzyme that exists in a different form
if someone presents to GP with raised ALP and RUQ pain what else would you check in LFTS
GGT
how do you differentiate between liver and bone ALP
also measure GGT
electrophoretic seperation
bone specific immunoassay
physiological causes of raised ALP
pregnancy
growth spurt in a child
pathological causes of raised ALP (>5x)
BONE: paget’s, osteomalacia
LIVER: cholestasis, cirrhosis
pathological causes of raised ALP (<5x)
BONE: tumour, infiltration, osteomyelitis
LIVER: hepatitis, infiltrative disease
causes of high serum amylase
mumps, pancreatitis, salivary disorders (salivary amylase is an isoform)
risk factors for statin related myopathy
polypharmacy
FH
high dose
PMH with a different statin
causes of a raised CK
being afrocarribean MI (>10x) Duchenne muscular dystrophy (>10x) rhabdomyelysis severe exercise
when are enzymes used to measure therapeutic response
Measurement of thiopurine methyltransferase (TPMT) activity is encouraged prior to commencing the treatment of patients with thiopurine drugs such as azathioprine, 6-mercaptopurine and 6-thioguanine
when are enzymes used to measure other substances
glucose oxidase as a reagant to measure glucose
diagnostic criteria of an acute MI
troponin rise and fall with
a) ischemic symptoms
(b) pathologic Q waves on the ECG
(c) ECG changes indicative of ischemia
(d) coronary artery intervention
what is the unit of enzyme activity
U
quantity of enzyme to catalyse 1umol of substrate per minute
what is the ratio of intracellular to extracellular fluid
2:1
which has more sodium, intracellular or extracellular fluid
extracellular
which has more potassium, intracellular or extracellular fluid
intracellular
define osmolarity
number of particles in a solution
units of osmolaLity when measured with an osmometer
mmol/Kg
units of osmolarity when it is calculated
mmol/L
equation for osmolarity
2(Na+K)+ urea +glucose
pathological determinants of osmolarity
endogenous: glucose
exogenous: mannitol and ethanol
normal range of osmolality
275-295mmol/kg
what is the difference between osmolarity and osmolality
osmolar gap
if high- metabolic acidosis
what does an osmolar gap mean re metabolic acidosis
osmolaRity is lower than osmolaLity
extra unmeasured solutes are dissolved in serum
how is sodium concentration maintained
actively pumped from ICF to ECF by Na/K/ATPase
how do you know if someone has true hyponatraemia
serum osmolarity is low and sodium is also low
symptoms of hyponatraemia
N&V (<136mmol)
confusion <131mmol)
seizures and non-cardiogenic pulm oedema (<125mmol)
coma(<117mmol)
causes of hyponatraemia with a high serum osmolarity
mannitol/ glucose infusion
causes of hyponatraemia with a normal serum ofmolarity
pseudohyponatraemia (paraproteinaemia or hyperlipidaemia)
causes of hyponatraemia with low serum osmolarity
true hyponatraemia
causes of hyponatraemia with hypervolaemia
THE FAILURES
heart failure, renal failure and liver failure
FLUID RESTRICT
causes of hyponatraemia with euvolaemia
THE ENDOCRINE CAUSES
hypothyroidism, glucocorticoid insufficiency or SIADH
causes of hyponatraemia with hypovolaemia
SALT LOSS
D&V
diuretics
salt losing nephropathy
tests in a euvolaemic hyponatraemic patient
TFT
short synACTHen test
paired urine
serum osmolarity
treatment of a hypovolaemic hyponatraemic patient
restore fluid with 5% dextrose
what determines urine sodium output
RAS aldosterone renal function naturitic peptides (BNP and ANP)
where is aldosterone synthesised
zona glomerulosa of the adrenal gland
function of aldosterone
sodium reabsorption in kidney and urinary excretion of potassium
how to differentiate between renal and non renal causes of hyponatraemia
urinary sodium
20mmol/L is always cutoff
what rate do you correct sodium at and why
1mmol/L/hr
risk of central pontine myelinolysis
what is central pontine myelinolysis
psuedobulbar palssy, parapariesis, locked in syndrome,
causes of hyponatraemia after surgery
over hydration with hypotonic saline
increase ADH release by body as a stress response to surgery
what type of hyponatraemia is SIADH
euvolaemic hyponatraemia
is the urine osmolarity high in SIADH
YES
lots of water reabsoption
causes of SIADH
malignancy:SCLC, pancreas, prostate and lympohoma
chest: TB
CNS: abscess, trauma, meningoecephalitis
drugs: SSRI, carbamezapine, opioids, PPI
treatment of SIADH
FLUID RESTRICT
can use tolvaptan and demeclocycline to induce DI (not on NHS)
define hypernatraemia
plasma sodium is greater than 148mmol/L
complications of rapid correction of hypernatraemia
cerebral oedema
causes of hypovolaemic hypernatraemia
water is lost more than sodium
D&V
burns
renal loss: loop diuretics or osmotic diuresis after initial hyponatraemia
causes of euvolaemic hypernatraemia
DI
skin (sweating, fever)
resp (tachypnoea)
symptoms of hypernatraemia
thirst, confusion, seizures, coma
causes of hypervolaemic hypernatraemia
CONNS syndrome (excess mineralocorticoids) hypertonic saline
diabetes indipidus
HYPERNATRAEMIA (euvolaemia)
no ADH or insensitive to ADH
how to diagnose DI
8 hour fluid deprivation test
urine DOES NOT CONCENTRATE
how to differentiate between cranial and nephrogenic DI
cranial- urine concentrates with desmopressin administration, nephrogenic stays dilute
primary polydipsia
sx of DI but urine concentrates 400-600mosm/kg in fluid deprivation
causes of nephrogenic DI
lithium, democlocycline
inherited channelopathy
hypercalcaemia
what is the predominant intracellular cation
potassium
causes of hypokalaemia
1) GI loss
2) renal loss
3) drugs : Beta blockers, insulin causing redistribution
metabolic alkalosis causing redistribution into cells
4) renal tubular acidosis
5) hypomagnesia
Type 1 renal tubular acidosis
failure of hydrogen ion pumping at distal tubule
H+ is not excreted resulting in acidosis and hypokalaemia
SEVERE
Type 2 renal tubual acidosis
failure to reabsorb bicarbonate at the proximal tubule resulting in acidosis and hypokalaemia
mild
tybe 4 renal tubular acidosis
aldosterone deficiency/ resistance
acidosis with hypERkalaemia
how to treat hypokalaemia
sandoK
monito
IV KCl if <3mmol/L but infusion rate of <10mmol/hr to avoid arrthmia
increased intake causing hyperkalaemia
fasting
parenteral
stored blood
transcellular movement causing hyperkalaemia
acidosis
DKA
rhabdomyelysis
reduced excretion causing hyperkalaemia
acute renal failure potassium sparing diuretics e.g. spironalactone ARB ACEI NSAIDS
treatment of hyperkalaemia
10%10ml calcium gluconate 100ml 20% dextrose 10 units insulin salbutamol as an adjunct TREAT THE CAUSE
causes of metabolic acidosis
DKA
renal tubular acidosis
intestinal fistula
causes of metabolic alkalosis
pyloric stenosis
hypokalaemia
ingestion of bicarbonate
causes of respiratory acidosis
lung injury e.g. pneumonia
COPD
decreased ventilation: morphine OD
causes of respiratory alkalosis
mechanical ventilation
panic attack
causes of elated anion gap metabolic acidosis
Ketoacidosis
Uraemia
Lactic acidosis
Toxins (ethylene glycol, methanol, paraldehyde, salicylate)
anion gap calculation
(Na+K)-(cl+HCO3)
markers for liver function
clotting (INR)
albumin
glucose
markers of liver cell damage
ALT AST GGT alk phos bilirubin
AST:ALT ratio in alcoholic liver disease
2:!
AST:ALT ratio in viral liver disease
<1:1
when does alk phos rise
PREGNANCY
cholestasis
when do you use GGT
to confirm raised liver ALP
elevated in chronic alcohol disease, bile duct disease and metastatic disease
define porphyria
deficiency of enzyme in the haem synthesis pathway causing overproduction of toxic haem precursors resulting in neurovisceral attacks or cutaneous skin lesions
where is ALA synthase found
every cell
what is 5ALA also known as
delta ALA
what is PBG synthase also known as
ALA dehydratase
how is acute intermittent porphyria inherited
autosomal dominant
what is the defect in acute intermittent porphyria
HMB synthase deficiency
symptoms of acute intermitten porphyria
neurovisceral sx
abdo pain, seizures, psych disturbances, vomiting, tachycardia, sensory loss, hypertension, weakness, constipation
how to diagnose acute intermittent porphyria
port wine urine
ALA and PBG in urine
factors inducing AIP attack
starvation, premenstrual, stress and ALA synthase inducers e.g. barbiturates, ethanol and steroids
how to treat AIP
IV haem arginate
IV carbohydrate
analgesia
avoid precipitants
ALA synthase deficiency
NOT A PORPHYRIA
linked with x-linked sideroblastic anaemia
ALA dehydratase deficiency (plumboporphyria)
acute neurovisceral
coma, bulbar palsy, abdo pain
build up of ALA
another name for ALAdehydratase
PBG synthase
congenital erythropoeitc porphyria enzyme
deficiency in uroporphyrinogen III synthase
CEP substance buildup
ALA PBG and HMB
CEP symptoms
non acute cutaneous lesions
skin blistering and fragility
Porphyria cutanea Tarda (PCT)
non acute skin lesions
PCT symptoms
vesicles on sun exposed areas with blistering and scarring
raised uroporphyrinogen and ferritin
HCP
acute skin
use stool sample
skin blistering in sun exposed areas
Variegate porphyria (VP)
protoporphyrinogen deficiency
variegate porphyria pathology
build up in protopophyrinogen IX
found in stool
EPP
defiency in ferrochelatase
paediatric
non blistering redness minutes after sun exposure
hormones of the anterior pituitary
Prolactin TSH GH LH FSH ACTH
symptoms of anterior pituitary failure
galactorrea
amenhorrea
what complication is caused by a pituitary macroadenoma and how is it tested
bitemporal hemianopia
Humphrey’s 30-2 test
what level of prolactin makes you “almost” certain its a prolactinoma
6000
how to investigate a suspected prolactinoma
Visual fields
Pituitary function test (stress test)
MRI
What is a pituitary function test
induce stress by fasting (hypoglycaemia)
LH
TRH
this should induce ACTH and GH release
in a functioning pituitary what hormones are produced ina pituitary stress test
ACTH via CRH
GH via GHRH
what needs to be checked before a pituitary stress test
no epilepsy
no cardiac risk factors
how to rescue a hypoglycaemic patient in a pituitary stress test
get good IV access
50ml 20% dextrose
what quantities of hormone are given in pituitaty function test (CPFT)
200mcg TRH
100mcg LHRH
0.15 units insulin/kg
what needs to be replaced in anterior pituitary failure
HYDROCORTISONE
thyroxine
oestrogen
GH
how to treat prolactinoma
cabergoline
bromocriptine
how does a nonfuncitoning adenoma cause hyperprolactinaemia
it presses on the stalk so dopaminecan’t reach the pituitary
adaquate cortisol response in CPFT
Adequate cortisol response = ↑ greater than 170 nmol/l to above 500nmol/l.
adaquate GH response in CPFT
Adequate GH response = ↑ greater than 6mcg/L
adequate TSH response in CPFT
> 5mU/L
30 minute response greater than 60 minute
normal LH response in CPFT
> 10U/L
normal FSH response in CPFT
> 2U/L
reduced TSH
reduced T4
central hypothyroidism
hypothalamic/ pituitary failure
high TSH
low T4
hypothyroidism
high TSH
normal T4
treated hypothyroidism
subclinical hypothyroidism
high TSH
TSH secreting tumour
TSH resistance
low TSH
high T3, T4
hyperthyroidism
causes of high uptake hyperthryrodism
Graves disease
toxic multinodular goitre
single thyroid adenoma
causes of low uptake thyroiditis (hyperthyroidism)
De Quervain’s thyroiditis
post partum thyroiditis
what is de quervains thyroiditis
post viral painful nodule causing hyperthyroidism
causes of autoimmune hypothyroidism
Hashimoto’s thyroiditis
primary autoimmune hypothyroidism
what is hashimoto’s thyroiditis
autoimmune disorder post viral antibodies cause initial hyperthyroidism then hypothyroidism.
non-autoimmune causes of hypothyroidism
iodine deficiency
drug induced- lithium, amiodarone
post RT/ thyroidiectomy
treatment of high uptake hyperthyroidism
beta blockers
carbimazole
treatment of de quervains hyperthroidism
NSAIDS
beta blockers
types of thyroid cancer
medullary papilliary follicular anaplastic lymphoma
medullary thyroid cancer
MEN2a
produces calcitonin
how to differentiate pituitary cushings from non-pituitary
dexamethasone suppresion test
low dose will fail to suppress pituitary cushings but high dose will
how to test for addisons disease
synACTHen test
give hydrocortisone unless adrenal lesion when fludrocortisone needs to be given first
investigation in conn’s syndrome
aldosterone: renin ration
aldosterone is high but renin is low
pathology of conn’s syndrome
HYPERALDOSTERONISM very high BP resistant to tx high sodium low potassium
treatment of conn’s syndrome
aldosterone antagonists
potassium sparing diuretcis e.g. spironalactone, amiloride
how to diagnose a phaeochromocytoma
24 hour urinary and plama metadremaline/ catecholamine measurement
how to treat a phaeochromocytoma
alpha blockade then beta blockade
resect tumour once bp is well controlled
phenytoin toxicity
ataxia
nystagmus
phenytoin under-treatment
seizures
phenytoin cautions and treatment
at high levels liver becomes saturated and so blood levels surge: reduce/ omit doses
digoxin toxicity
arrythmias
xanthopsia- seeing yellow
confusion
heart block
digoxin under-treatment
arrythmias
cautions with digoxin
levels increase if hypokalaemia
caution with renal impairment patients
treatment of digoxin toxicity
digibind
signs of lithium toxicity
lethargy tremor fits arrythmia renal failure
signs of lithium undertreatment
mania
cautions with lithium treatment
hyponatraemia or decreased renal function/ diuretics cause impaired excretion and levels rise
gentacmycin toxicity
tinitus
deafness
nystagmus
renal failure
theophyline
COPD treatment
theophyline toxicity
arrthmia
tremor
anxiety
convulsions
theophyline under-treatment
no effect on bronchial smooth muscle
cautions in theophyline therapy
if erythromycin or phenytoin use levels rise
takes longer for non-smokers liver to clear
if liver failure difficulty clearing
causes of primary hypercholestrolaemia
type 2 familial hypercholesterolaemia
polygenic hypercholesterolaemia
familial hyperalpha-lipoproteinaemia
phyosterolaemia
causes of primary hypertriglyceridaemia
type I, V, VI
primary mixed hyperlipidaemia
familial combined hyperlipidaemia
familial hepatic lipase deficiency
familial dysbetalipoproteinaemia
causes of hypolipidaemia
AB lipoproteinaemia
hypo alpha lipoproteinaemia
hypobeta lipoproteinaemia
Tangier disease
what does PCSK9 do
binds LDLR and forces its degradation
what happens if PCSK9 is low
low LDL levels
autosomal dominant mutation in familial hypercholesterolaemia (type 2)
PCSK9. apoB, LDLR
autosomal recessive causes of type 2 familial hypercholesterolaemia
LDLRAP1
cause of familial hyperalphalipoproteinaemia
CETP deficiency
cause of phytosterolaemia
ABC G5 and G8
cause of type 1 primary hypertriglyceridaemia
lipoprotein lipase or apoC II
cuase of type 5 primary hypertriglyceridaemia
apoA V deficiency
cause of type 6 hypertriglyceridaemia
increased triglyceride synthesis
cause of alphabetalipoproteinaemia
MTP deficiency
hypoA- lipoproteinaemia
apoA-I mutation
hypoB lipoproteinaemia
apo~B protein is truncated
tangier deficiency
HDL deficiency
lipoprotein order of desity
chylomicron FFA VLDL IDL LDL HDL
vitamin A excess
exfoliative dermatitis
vitamin A deficiency
colour blindness
vitamin A testing
in serum
vitamin D deficiency
osteomalacia/ rickets
vitamin D excess
hypercalcaemia
vitamin D testing serum
serum
vitamin E name and where found
tocopherol and in serum
vitamin E deficiency
anaemia
neuropathy
vitamin K
defective clotting
vitamin K testing
PTT
vitamin K name
phytomenadione
how to test vit B1
RBC transketolase
vitamin B1
Beri Beri
wernicke’s
neuropathy
vitamin B2 deficiency
glossitis
vitamin B2 test
RBC glutathione reductase
vitamin B6 name
pyridoxine
vitamin B6 deficiency
anaemia
dermatitis
vitamin B6 testing
RBC AST activation
vitamin B6 excess
neuropathy
vitamin B12 name
cobalamine
vitamin B12 deficiency
`pernicious anaemia
how to test vitamin B12
serum B12
vitamin C name
abscorbate
vitamin C deficiency
scurvy
vitamin C excess
renal stones
vitamin C testing
plasma
folate deficiency
neural tube defects
megaloblastic anaemia
how to test folate levels
RBC folate
vitamin B3 name
niacin
vitamin B3 deficiency
pellagra (dementia, diarrhoea, dermatitis)
iron deficiency
hypochromic anaemia
how to test iron levels
ferratin
FBC
Fe
iodine deficiency
goitre
hypothyroidism
zinc deficiency
dermatitis
copper deficiency
anaemia
copper excess
wilsons
copper levels testing
cu caeoplasmin
flouride deficiency
dental caries
flouride excess
flourosis
what is screened for in the gunthrie test
phenylketonuria medium chain acylcoA dehydrogenase deficiency congenital hypothyroidism CF sickle cell disease
what is phenylketonuria
phenylanine hydroxylase deficiency
how to you screen for phenylketonuria
phenylanine levels in blood
congenital hypothyroidism pathology
dys/agenesis of the thyroid gland
Cystic fibrosis pathology
CFTR gene mutation
screening for congenital hypothyroidism
TSH levels
how to test for cystic fibrosis
immune reactive trypsin is positive
how to detect medium chain acyCoA dehydrogenase deficiency
acylcarnatine levels by tandem mass spectroscopy
specificity
those who test negative correctly
Total negative/(false postive +true negative)
sensitivity
correctly test positive
Total positive/ (false negative + true positive)
Positive predictive value
the probablitiy test will correctly identify someone with the disease
TP/ (TP+FP)
negative predictive value
the probability that somebody without the disease tests negative
TN/ (TN+FN)
fasting glucose levels to diagnose diabetes
> 7
random glucose levels to diagnose diabetes
> 11.1
OGTT levels to diagnose diabetes
> 11.1
HBA1c levels to diagnose diabetes
> 48
cause of hyperinsulinaemic hypoglycaemia
iatrogenic insulin
sulfonylurea excess
insulinoma
cause of hypoinsulinaemic hypoglycaemia with ketones
alcohol binge no food liver failure pituitary insufficiency addison's
cause of hypoinsulinaemic hypoglycaemia with no ketones
non pancreatic neoplasms e.g. fibromata or fibrosarcomata
non-islet tumour hypoglycaemia
low glucose, low insulin, low c eptite, low FFA and low ketones
mmeachanism of non-islet cell tumour hypoglycaemia
paraneoplastic syndrome
tumouyr secretes big IGF2 which binds to IGF1 and insulin receptors
normal GFR
120 ml/minute
age related GFR decline
1ml/hr/yr
clearance definition
volume of plasma that can be cleared of a marker per unit time
conditions for a marker to measure clearance
marker cannot bind to serum protein
marker must be freely filtered by glomerulus
marker cannot be secreted/ reabsorped by glomerular cells
gold standard measure of GFR
inulin
endogenous marker of GFR
creatinine
what to measure in a single sample of urine
dipstick
microscopy
protein: creatinine ratio
what to measure in 24 hour urine collection
stone forming elements
proteinuria quantification
creatinine clearance
electrolytes
urine microscopy
test crystal rbc wbc casts bacteria
AKI definition
creatinine clearance rising 1.5x baseline in 48 hours or rising over26.5 in 48 hours
severe AKI creatinine change
3x rise in creatinine clearance
pre-renal cause of AKI
reduced renal perfusion
hypovolaemia
renal cause of AKI
vascular, tubal, interstitial or glomerular
post renal causes of AKI
outflow obstruction
indications for emergency dialysis
pulmonary oedema refractory hyperkalaemia ,metabolic acidosis uraemic encephalopathy lithium toxicity
common causes of CKD
diabetes arethosclerotic diseae hypertensionchronic glomerulonephritis infective or obstructive uropathy polycystic kidney disease
consequences of CKD metabolic hormonal CVS urea
metabolic: hyperkalaemia, acidosis
hormonal: reduced epo and anaemia and hyperparathyroidism secondary to low vit D
CVS: vascular calcification and atherosclerosis, uraemic cardiomyopathy
uraemia
CKD staging
1: GFR>90
2. mild GFR 60-89
3 moderate GFR 30-59
4 severe GFR 15-29
5. ESRF <15 GFR or on dialysis
two actions of purines
secondary messengers for hormones e.g. cAMP
energy transfer e.g. ATP
enzyme that catalyses xanthine to urate
xanthine oxidase
enzyme that catalyses hypo-xanthine to xanthine
xanthine oxidase
enzyme that catalyses urate to allantoin
uricase
does solubility of monosodium urate increase or decrease with temperature
decrease
what happens to urate in the proximal convoluted tubule
reabsorbed then secreted
what is Lesch-Nyhan syndrome
complete HGPRT deficiency
symptoms of lesch-nyhan syndrome
retardation choreiform movements self mutilation spasticity hyperuricaemia developmental delay
when do lesch-hyhan symptoms appear
developmental delay at six months
self mutilation at 1-16
choreiform movements at 1 yr
causes of hyperuricaemia
primary causes of increased urate production
Lesch nyhan syndrome fructose intolerance PRPP synthetase overactivity partial HRPT deficiency glycogen storage disorder
causes of hyperuricaemia
secondary increased urate production
myeloproliferative disorders lymphoproliferative disorders carcinomatosis chronic haemolytic anaemia Gaucher's disease
causes of hyperuricaemia
primary causes of reduced urate excretion
FJHN
causes of hyperuricaemia
secondary causes of reduced urate excretion
Bartter syndrome chronic renal failure aspirin diuretics Downs Saturine gout
causes of hypouricaemia
decreased urate production
xanthine oxidase defiicency
allopurinol
liver failure
causes of hypouricaeia
increased urate excretion
fanconi syndrome
idiopathic hypouricaemia
URAT1 inactivation
drugs
joint most commonly affected in gout
1st MTP
how to manage acute gout
NSAIDS
colchacine
glucocorticoids
how to chronically mange gout
allopurinol
diet modification
drink lots of water
probenecid
how to increase renal excretion of uric acid in chronic gout patients
probenecid
what does allopurinal interact with
azothiprine
makes its intermediay 6-mercaptopurine last longer
how to diagnose gout
Tap effusion
view under red polarised light
negatively bifringent crystals
what is pseudogout
calcium pyrophosphate
how to diagnose psuedogout
positively brifringent crystals under blue polarised light
PCSK9 gain of function mutation inheritance
autosomal dominant
more LDL receptor degradation resulting in familial hypercholesterolaemia
how to treat obesity
hypocaloric diet and exercise
orlistat
bariatric surgery
metabolic acidosis abnormalities
low PH
high bicarbonate
low co2 if compensated
causes of metabolic acidosis
increased H+ with reduced bicarbonate
increase H+ production: DKA
reduced H+ excretion: renal tubular acidosis
bicarbonate loss: intestinal fistula
respiratory acidosis findings on ABG
raised CO2
raised H+
raised HCO3-
causes of respiratory acidosis
poor ventilation
poor lung perfusion
impaired gas exchange
metabolic alkalosis findings on ABG
reduced H+
increased bicarbonate
if compensted high pCO2
causes of metabolic alkalosis
H+ loss: pyloric stenosis
hypokalaemia
bicarbonate ingestion
findings on ABG for respiratory alkalosis
low H+
low CO2
low HCO3
causes of respiratory alkalosis
artificial ventilation
voluntary
stimulation of respiratory centre
what acidosis/ alkalosis does aspirin overdose cause
resp alkalosis
criteria of a screening test
Important health problem Accepted treatment Facilities for diagnosis and treatment Latent or early symptomatic stage Suitable test or examination Test should be acceptable to the population Natural history understood Agreed policy on whom to treat as patients Economically balanced Continuing process
in phenylketonuria where are abnormal metabolites found and what are they
phenylalanine in blood
phenylacetic acid in urine
when is gunthrie test performed
day 5-8 of life
urea cycle defects
HHH
Type 2 citrullinaemia
what are urea cycle defects associated with
encephalopathy
respiratory alkalosis
irreversible neurological damage
neonatal complications (common)
retinopathy of prematureity respiratory distress syndrome PDA Intraventricular haemmorhage necrotising enterocolitis
what is the pathology of necrotising enterocolitis
inflammation of the bowel wall leading to necrosis and perforation
symptoms of necrotising enterocolitis
abdo distension
bloody stool
signs of necrotising enterocolitis on AXR
intramural air
when is full GFR reached
age 2
what are the consequences of neonates not having complete GFR
limited ability to exchange Na+ for H+
slow excretion of solute load
what is the difference in the proximal tubule between children and adults
shorter in children
what is the significance of a shorter proximal tubule in children
LOWER RESORPTIVE CAPACITY but usually sufficient for small solute load
what is the difference in the loop of henle and DCT between adults and children
shorter in children
what is the difference in the loop of henle and DCT between adults and children
lower concentrating ability
what is the maximum urine osmolarity in a child
700mmol/kg
what is the difference in DCT between adults and children
DCT is comparitively unresponsive to aldosterone
what changes occur in the volume of ECF in the first weeks of life
it falls by 40%
cause of hypernatraemia in neonates
dehydration
salt poisoning
how to differentiation causes of hypernatraemia in a neonate
paired urine/ blood creatine, urea and electrolytes
what is the defect in congenital adrenal hyperplasia
21 hydroxylase deficiency
what are symptoms of congenital adrenal hyperplasia
hyponatraemia
hyperkalaemia with volume depletion
hypoglycaemia
ambiguous genitalia in females
growth acceleration in children
what hormones are lacking in congenital adrenal hyperplasia
aldosterone
cortisol
causes of hyperbilirubinaemia (unconjugated bilirubine)
increased synthesis (RBC breakdown) increased enterohepatic circulation low rate of transport into the liver
what is the complication of hyperbilirubinaemia
bilirubin crosses BBB and causes kernicterus
conditions causing hyperbilirubinaemia
crigler-najar syndrome
G6PD deficiency
haemolytic disease e.g rhesus/ abo incompatibility
what is the definition of prolonged jaundice
14 days in term babies and 21 days in preterm babies
causes of prolonged jaundice
breast milk jaundice
congenital hypothyroidism
neonatal infection/ sepsis
what level of conjugated bilirubin is always pathological
> 20umol/L
causes of conjugated hyperbilirubinaemia
biliary atresia
choledocal cyst
ascending cholangitis if TPN
galactosaemia (inherited metabolic disorders)
what is conjugated hyperbilirubinaemia often associated with
cardiac abnormalities- situs inversus, polysplenia
hypocalcaemia in a newborn can lead to
osteopenia of premaurity
fraying, splaying and cupping of long bones
biochemistry of osteopenia
calcium is normal
phosphate is <1umol/L
alk phos> 1200U/L (10x adult ULN)
how do you treat neonatal osteopenia
calcium and phosphate supplements
presentation of rickets
bowing of legs, muscle hypotonia frontal bossing
genetic causes of rickets
pseudovitamin D deficiency 1- defective receptors
pseudovitamin D deficiency 1- defective renal hydroxylation
familial hypophosphataemia
familial phosphataemia
high urine phosphoethanolamine
low tubular maximal reabsorption of phosphate
hyponatraemia after prostate surgery
TURP syndrome
