chem Flashcards
1
Q
osmolality equation
A
2(Na +K) + glucose + urea
2
Q
what is the difference between osmolality and osmolarity
A
osmolality = /kg, more accurate
osmolarity = /litre, more practical
3
Q
what is the biggest contributor to osmolality
A
sodium
4
Q
what is osmolality gap
A
difference between calculated and measured osmolality, due to things not included in calc (sugars, alcohol)
5
Q
what is pseudohyponatraemia
A
reduced Na, normal/high osmolality
6
Q
HYPOvolaemic HYPOnatraemia with LOW urinary sodium
A
extra renal loss (vomiting, diarrhoea, burns)
7
Q
HYPOvolaemic HYPOnatraemia with RAISED urinary sodium
A
renal loss (diuretics, renal loss)
8
Q
HYPERvolaemic HYPOnatraemia with LOW urinary sodium
A
CCF, cirrhosis, nephrotic syndrome
9
Q
HYPERvolaemic HYPOnatraemia with RAISED urinary sodium
A
CKD
10
Q
EUvolaemic HYPOnatraemia with LOW urinary sodium
A
psychogenic polydipsia
11
Q
EUvolaemic HYPOnatraemia with RAISED urinary sodium
A
hypothyroid, SIADH, adrenal insufficiency
12
Q
HYPOvolaemic HYPERnatraemia
A
osmotic diuresis, diarrhoea, burns
13
Q
HYPERvolaemic HYPERnatraemia
A
hyperaldosteronism
hypertonic 3% saline
14
Q
hypernatraemia management
A
oral water intake
slow IV 5% dextrose
15
Q
causes of central diabetes insipidus
A
pituitary surgery, irradiation, tumour
16
Q
central diabetes insipidus management
A
desmopressin
17
Q
causes of nephrogenic diabetes insipidus
A
electrolyte disturbance (hypokalaemia, hyperglycaemia)
drugs (lithium)
18
Q
nephrogenic diabetes insipidus management
A
thaizides
19
Q
diabetes insipidus investigations
A
glucose - exclude DM
K - exclude hypo
Ca - exclude hyper
water deprivation test
20
Q
hypokalaemia features
A
muscle weakness, cramps, hypotonia
21
Q
causes of hypokalaemia - increased loss
A
GI loss (d+v, high output stoma)
renal loss (conn’s, diuretics)
22
Q
causes of hypokalaemia - increased cellular influx
A
insulin
beta agonists
refeeding syndrome
metabolic alkalosis
23
Q
hypokalaemia investigations
A
Mg - correct if low
if raised BP, aldosterone: renin ratio
24
Q
hypokalaemia management
A
mild-moderate (2.5-3.5) - oral sando K
severe (<2.5) IV replacement, continuous ECg
25
hyperkalaemia ECG features
tall tented T waves, small p, wide QRS
26
hyperkalaemia causes - artifact
haemolysis
27
hyperkalaemia causes - iatrogenic
massive blood transfusion
excess supplmentation
28
hyperkalaemia - reduced excretion
renal disease
addison's
drugs (ACEi, ARB, K sparing diuretics)
29
hyperkalaemia - increased cellular release
tissue breakdown
30
hyperkalaemia investigations
renal function
cortisol/ short ACTHen test
CK
31
hyperkalaemia management
if >6.5 or ECG changes
IV calcium gluconate
IV insulin w/ dextrose
32
what hormone has the opposite affect to PTH
calcitonin
33
hypocalcaemia features
peri-oral paraesthesia, long QT, spasm, tetany
34
hypocalcaemia causes
osteomalacia
hypoparathyroidism
35
hypocalcaemia investigations
ECG
bloods (Mg, phosphate, PTH, ALP)
dexa
36
hypocalcaemia management
mild (>1.9) - oral calcium/ vit D supplement
severe - IV calcium gluconate
37
hypercalcaemia features
stones, bones, abdo groins, psychic moans
38
hypercalcaemia causes (raised PTH)
primary/ tertiary hyperparathyroidism, late stage CKD
if primary hyper, suspect MEN1/2a
39
hypercalcaemia causes (low PTH)
malignancy
hyperthyroid
hypoadrenal
sarcoidosis
thiazides
40
hypercalcaemia Ix
myeloma screen
TFTs, cortisol
41
hypercalcaemia management
fluids
acute - IV normal saline
medical - bisphosphonates (if malignancy)
surgical - parathyroidectomy
42
isolated raised ALP
paget's disease
43
alcoholic hepatitis AST:ALT ratio
>2
44
viral hepatitis AST:ALT ratio
<1
45
hypothyroid autoimmune causes
primary atrophic (no goitre)
hashimoto's (goitre + anti-TPO/TG)
46
hypothyroid other causes (not autoimmune)
iodine deficiency
surgery/ radioactive ablation
drugs - amiodarone, lithium, carbimazole
47
myxoedema coma management
IV liothyronine
48
what is sick euthyroid
in severe illness
reduced T3, T4
initially increased TSH, then reduced
49
syndrome with increased TSH but normal T3/4
subclinical hypothyroidism
50
what antibody is associated with increased risk of hypothyroid in subclinical hypothyroid
anti-TPO
51
causes of hyperthyroid
graves
de quervain's thyroiditis
thyroid adenoma
amiodarone
toxic multinodular goitre
post-partum
52
focal lesions on thyroid reuptake scan
adenoma
53
multiple patchy lesions on thyroid reuptake scan
toxic goitre
54
generalised increased uptake on thyroid reuptake scan
graves
55
cold thyroid on reuptake scan
de quervain's
56
medical management of hyperthyroid
carbimazole or propylthiouracil
beta blockers for AF/ palpitations
lugol's iodine - make pt euthyroid for surgery
radio-iodine - risk permanent hypo
57
where is the pituitary gland
sella turcica just below optic chiasm
58
malignant causes of hypopituitarism
pituitary adenoma
craniopharyngioma
59
infective causes of hypopituitarism
TB
syphilis
60
infiltrative causes of hypopituitarism
sarcoid
lymphoma
61
iinfarct causes of hypopituitarism
sheehan's
apoplexy
62
tertiary causes of hypopituitarism
kallman's
prader-willi
63
what is combined pituitary function test
give GnRH, TRH and insulin, measure GH, cortisol, TSH, LH, FSH and prolactin every 30 mins for 2 hrs
64
hypopituitarism management
hydrocortisone
thyroxine
oestrogen/ testosterone
65
effects of pituitary macroadenoma
usually non-functional
bitemporal hemianopia
66
effects of pituitary microadenoma
GH or prolactin secreting
prolactin --> galactorrhoea, gynaecomastia, oligo/amennorhoea, loss of libido, impotence
GH --> acromegaly, organomegaly, heart failure sx, htn, dm, carpal tunnel
67
acromegaly Ix
glucose tolerance test
plasma IGF-1
68
pituitary adenoma management
octreotide (somatostatin analogue)
cabergoline or bromocriptine (dopamine agonist)
pegvisomant (Gh antagonist)
surgery - trans-sphenoidal debulking
69
most common type of thyroid tumour
papillary
70
second most common thyroid tumour
follicular
71
medullary thyroid cancer features
c-cells that produce calcitonin
linked to men2
5% of thyroid cancers
72
type of thyroid cancer linked with hashimoto's
lymphoma
73
anaplastic thyroid cancer features
elderly patients, poor prognosis
undifferentiated
74
management of papillary/ follicular thyroid cancer
surgery +/- radioactive iodine
replace thyroxine to completely supress TSH
monitor thyroglobulin levels
75
what is produced in the glomerulosa of adrenals
mineralocorticoids (aldosterone)
76
what is produced in the fasciculata of adrenals
glucocorticoids (cortisol)
77
what is produced in reticularis of adrenals
sex hormones
78
what is produced in adrenal medulla
catecholamines
79
most common cause of addisons in the UK
autoimmune
80
most common cause of addison's worldwide
TB
81
addison's features
postural drop, fatigue
weight loss, anorexia
vomiting, salt craving
skin/ mucosal pigmentation
82
addison's ix
9am cortisol >350 excludes hypoadrenalism
synACTHen test - if cortisol rises --> secondary cause (pituitary), if not then primary
hyponatraemia, hyperkalaemia
83
features of addisonian crisis
hypotension
hypovolaemia
hypoglycaemia
84
addisons management
hydrocortisone (double dose if unwell)
fludrocortisone
85
what is schmidt's syndrome
simultaneous hypoadrenalism and hypothyroid
86
cushings causes
primary - adrenal malignancy
secondary - pituitary adenoma, ectopic/ paraneoplastic
iatrogenic (exogenous steroids)
87
cushings ix
low dose dexmethasone suppression test - confirm syndrome
high dose dexamethasone suppression test - syndrome vs disease (adenoma)
88
cushings imaging
CT CAP/ adrenals
| MRI pituitary
89
ectopic cause cushings management
ketoconazole, metyrapone, mifepristone
90
primary cushings management
adrenalectomy +/- steroid replacement
91
CKD electrolytes
reduced NA, raised K, raised urea
92
addisons electrolytes
reduced Na, raised K, reduced glucose
93
ethanol electrolytes
reduced Na, raised osmolality
94
conn's syndrome electrolytes
raised Na, reduced K
95
D/V electrolytes
reduced Na, reduced osmolality, reduced urine osmolality
96
insulin OD electrolytes
reduced K, raised pH
97
bartter syndrome electrolytes
reduced K, raised pH, raised urinary calcium, hypotension
98
renal tubular acidosis electrolytes
reduced K, reduced pH
99
causes of RAISED anion gap metabolic ACIDOSIS
methanol/metformin
uraemia
DKA
iron
lactate
ethanol
salicyte
100
causes of NORMAL anion gap metabolic ACIDOSIS
diarrhoea
addison's
renal tubular acidosis
101
kallman's syndrome features
hypogonadotropic hypogonadism
reduced LH, FSH
anosmia
102
what is secondary hypoaldosteronism
pituitary defect --> reduced ACTH --> reduced aldosterone, cortisol
103
familial benign hypercalcaemia biochemistry
raised PTH, raised Ca, reduced urinary calcium
104
most common cause of secondary hyperparathyroidism
chronic renal failure
105
what is pseudohypoparathyroid
PTH resistance
raised PTH, raised phosphate, reduced Ca
106
causes of raised serum amylase
pancreatitis
mumps
107
ferritin in IDA
reduced
108
ferritin in anaemia of chronic disease
increased
109
ferritin in thalasaemia
normal
110
causes of bence-jones proteins
multiple myeloma
amyloid light chain amyloidosis
111
cause of low caeruloplasmin
Wilson's
112
causes of raised CEA
colorectal cancer, gastric cancer, pancreatic cancer
113
what is raised aFP associated with
hepatocellular carcinoma
114
vitamin B12 deficiency
megaolblastic anaemia
hypersegmented neutrophils
can get subacute cord degeneration - ataxia, progressive limb weakness, babinski sign positive
115
what does vitamin E deficiency cause
haemolytic anaemia
spino-cerebellar neuropathy - ataxia, areflexia
116
what does vitamin B6 deficiency cause
sideroblastic anaemia
seborrhoeic dermatitis
117
what can cause b6 deficiency
TB treatment (Isonazid)
118
what does B1 deficiency cause
wernicke's encephalopathy, korsakoff's syndrome
beri-beri wet - like heart failure
dry - ascending nervous system impairment
119
what does vitamin A deficiency cause
night blindness, conjunctival bitot's spots
predisposed to measles, diarrhoea
120
what does vitamin B2 deficiency cause
angular stomatitis, glossitis and/or corneal ulceration
121
features of homocystinuria
very fair skin, brittle hair
developmental delay
convulsions, skeletal abnormalities, thrombotic episodes
122
what do you supplement homocystinuria pts with
B6
123
PKU features
fair hair, developmental delay, severely impaired IQ, eczema, seizures
124
von gierke's syndrome features
hypoglycaemia
hepatomegaly, enlarged kidneys
125
maple syrup urine disease features
toxic encephalopathy (lethargy, poor feeding, hypotonia, seizures)
sweet odour, sweaty feet
126
fabry's syndrome features
developmental delay with dysmorphia
cherry red spots
deafness, blindness, movement disorders
127
SCAD deficiency features
failure to thrive, hypotonia, metabolic acidosis, hyperglycaemia
128
galactosaemia features
vomiting, jaundice, hepatomegaly after milk ingestion
129
toxicity features of phenytoin
hypotension
heart block
ventricular arrhythmias
ataxia
130
toxicity features of lithium
D+V, coarse tremor, dysarthria
convulsions
renal failure
131
toxicity features of gentamicin
deafness, renal failure, balance/ vision issues
toxicity potentiated by kidney function, use of vancomycin
132
toxicity features of digoxin
tiredness, blurred vision, nausea, abdo pain, confusion
prolonged PR, bradycardia
133
toxicity features of theophylline
nausea, diarrhoea
tachycardia, arrhythmias, headaches, seizures
potentiated by erythromycin, ciprofloxacin
134
toxicity features of procainamide
fever, rash
agranulocytosis
135
toxicity features of methotrexate
ulcerative stomatitis
leukocytopenia
pulmonary fibrosis
136
toxicity features of carbamezapine
headaches, ataxia, abdo pain
SIADH
aplastic anaemia
137
toxicity features of cyclosporine
acute renal failure
138
what electrolyte abnormality does metabolic alkalosis cause
HYPOkalaemia
139
acute renal failure biochemical picture
HYPERkalaemia
metabolic acidosis
140
what electrolyte abnormality can carbamezapine cause
hyponatraemia
141
PTH resistance with low calcium
pseudohypoparathyroidism
142
PTH resistance with normal calcium
pseudopseudohypoparathyroidism
143
test for thiamine deficiency
red blood cell transketolase activity
144
test for B2 (riboflavin) deficiency
red blood cell glutathione reductase
145
riboflavin deficiency manifestation
glossitis
mouth ulceration
dry skin
146
test for B6 (pyridoxine) deficiency
red cell aspartate aminotransferase
147
B6 deficiency manifestation
seborrhoeic dermatitis like rash
angular chellitis
confusion, neuropathy
can be cause by isoniazid
148
conn's syndrome picture
hypertension
hypokalaemia
metabolic alkalosis
149
gout vs pseudogout birefringence
gout = negatively birefringent
pseudogout = positive birefringence
150
gout exacerbating factors
alcohol
aspirin
thiazide diuretics
chemo
151
acute gout management
NSAIDS, colchicine
152
long term gout management
allopurinol
153
causes of metabolic acidosis with raised anion gap
methanol
uraemia
DKA
propylene glycol
isoniazid
lactic acidosis (shock, infection , ischaemia)
ethylene glycol
salicylates
154
anion gap calculation
Na + K - HCO3 - Cl
155
chronic renal failure phosphate
RAISED
156
which bone cells produce ALP
osteoblasts
157
cataracts, poor feeding, lethargy, conjugated hyperbilirubinaemia with hepatomegaly and reducing sugars in urine after starting milk
galactosaemia
158
alcohol abuse and chronic pancreatitis can cause reduced absorption of fat soluble vitamins and as such cause
osteomalacia
159
reduced absorption of dietary vitamin D causes what bloods
LOW 25-hydroxy-cholecalciferol
HIGH 1,25-dihydroxy-cholecalciferol
160
which vitamin D metabolite is produced following hydroxylation in the kidney stimulated by PTH?
1,25-dihydroxy-cholecalciferol
161
causes of raised ALP
liver related (cholestasis, hepatitis, fatty liver, tumour)
drugs (phenytoin, erythromycin, carbamezapine, verapamil)
bone disease (paget's, renal osteodystrophy, fracture)
vitamin D deficiency, secondary hyperparathyroidism
malignancy (bone metastases, breast, colon, Hodgkin's lymphoma)
162
vitamin D3 deficiency (Pellagra)
dementia
diarrhoea
dermatitis
death
163
symptoms of vitamin E deficiency
haemolytic anaemia
spinocerebellar degeneration
peripheral neuropathy
164
list the fat soluble vitamins
A
D
E
K
165
how many half lives does a drug take to reach steady state
4-5
166
hypoketotic hypoglycaemia with hepatomegaly and cardiomyopathy
MCADD
167
pituitary failure leads to lack of
ACTH
TSH
168
biochemical cause of acute pancreatitis
hypercalcaemia
169
drugs that lead to reduced serum K concentration
calcium resonium
insulin
salbutamol
sodium bicarbonate
170
which toponin is the best marker of MI
Troponin I
171
best enzyme marker to detect reinfarction of heart
CK MB
172
what is a cause of facitious hypoglycaemia other than exogenous insulin
sulfonylureas
173
cyanide poisoning first line
hydroxocobalamin
174
MEN1 features
Pituitary adenoma
Parathyroid hyperplasia
Pancreatic tumours
(3 Ps)
175
MEN 2A features
Parathyroid hyperplasia
Medullary thyroid carcinoma
Phaeochromocytoma
176
MEN 2B features
Medullary thyroid carcinoma
Phaeochromocytoma
marfanoid body habitus
mucosal neuromas
177
inheritance of MEN disorders
autosomal dominant
178
gilbert's inheritance
autosomal recessive
179
enlarged orange tonsils, with hepatomegaly, splenomegaly
tangier disease
180
what can't you give with azathioprine in pts with TPMT deficiency
allopurinol
181
term for increased bone density
osteosclerosis
182
looser zones
osteomalacia
183
which cholesterol transport channel does ezetimibe target
NPC 1L1
184
cardiac protection in hyperkalaemia
calcium gluconate
185
how to determine if it is a true hyponatraemia
serum osmolality
186
where are bile acids reabsorbed
terminal ileum
187
which enzyme has reduced activity in Gilbert's
UDP glucuronyl transferase
188
rickets x ray findings
widened epiphysis at wrists
bowed legs
189
allopurinol MOA
xanthine oxidase inhibition
190
in sarcoidosis, granulomatous tissue can produce which enzyme to lead to hypecalcaemia
1-alpha hydroxylase
191
ApoE4 gives increased risk of developing what
alzheimers
192
what can rapid correction of hyponatraemia cause
central pontine myelinolysis
193
central pontine myelinolysis symptoms
lethargy, issues speaking, swallowing, walking
194
condition where there is almost complete failure of PCT to reabsorb molecules
fanconi syndrome
195
causes of fanconi syndrome
congenital
wilson's disease
treatracyclines
MM
lead poisoning
