Pathology - Chemical Pathology Flashcards
flashcards (400 cards)
1
Q
What percentage of body weight is water?
A
60%
2
Q
What percentage of body weight is intracellular fluid?
A
40%
3
Q
What percentage of body weight is extracellular fluid?
A
20%
4
Q
Normal range for serum osmolality?
A
275-295 mmol/kg
5
Q
Normal range for sodium?
A
135-145 mmol/L
6
Q
What is mild hyponatraemia range?
A
130-135 mmol/L
7
Q
At what sodium level do seizures occur?
A
<125 mmol/L
8
Q
At what sodium level does coma occur?
A
<117 mmol/L
9
Q
Maximum sodium correction per 24 hours?
A
8-10 mmol/L
10
Q
What causes central pontine myelinolysis?
A
Rapid sodium correction
11
Q
SIADH diagnostic criteria - plasma osmolality?
A
<270 mmol/kg
12
Q
SIADH diagnostic criteria - urine sodium?
A
> 20 mmol/L
13
Q
SIADH diagnostic criteria - urine osmolality?
A
> 100 mmol/kg
14
Q
What defines hypernatraemia?
A
> 148 mmol/L
15
Q
Normal potassium range?
A
3.5-5.5 mmol/L
16
Q
What ECG change occurs first in hyperkalaemia?
A
Tall tented T waves
17
Q
At what K+ level is intervention needed with ECG changes?
A
> 5.5 mmol/L
18
Q
At what K+ level is intervention needed regardless of ECG?
A
> 6.5 mmol/L
19
Q
First treatment for hyperkalaemia?
A
Calcium gluconate 10%
20
Q
What does calcium gluconate do in hyperkalaemia?
A
Cardioprotective only
21
Q
Normal pH range?
A
7.35-7.45
22
Q
Normal CO2 range?
A
4.7-6 kPa
23
Q
Normal bicarbonate range?
A
22-30 mmol/L
24
Q
Normal anion gap range?
A
14-18 mmol/L
25
KULT mnemonic stands for?
Large ion gap metaolic acidosis
Ketoacidosis, Uraemia, Lactic acidosis, Toxins
26
Normal osmolar gap?
<10
27
What does ALT stand for?
Alanine aminotransferase
28
What does AST stand for?
Aspartate aminotransferase
29
What does ALP stand for?
Alkaline phosphatase
30
AST:ALT ratio in alcoholic liver disease?
2:1
31
Best marker of acute liver function?
Prothrombin time
32
What causes raised ALP >5x ULN in bone?
Paget's disease
33
What is Gilbert syndrome?
Impaired bilirubin conjugation
34
What causes unconjugated hyperbilirubinaemia?
Haemolysis
35
What causes conjugated hyperbilirubinaemia?
Biliary obstruction
36
Most common porphyria?
Porphyria cutanea tarda
37
Acute intermittent porphyria - key feature?
No skin symptoms
38
Acute intermittent porphyria - urine finding?
Raised PBG and ALA
39
Porphyria cutanea tarda - skin lesion type?
Blistering
40
Treatment for acute porphyria?
IV haem arginate
41
Normal range for TSH?
0.33-4.5 mU/L
42
Normal range for free T4?
10.2-22.0 pmol/L
43
What does raised TSH with low T4 indicate?
Hypothyroidism
44
What does low TSH with raised T4 indicate?
Hyperthyroidism
45
First-line antithyroid medication?
Carbimazole
46
Serious side effect of carbimazole?
Agranulocytosis
47
What is thyroid storm?
Acute hyperthyroid emergency
48
Most common cause of hyperthyroidism?
Grave's disease
49
Most common thyroid cancer?
Papillary
50
Papillary thyroid cancer spread pattern?
Lymph nodes
51
Medullary thyroid cancer tumour marker?
Calcitonin & CEA
52
What is MEN1 triad?
Pituitary, Pancreatic, Parathyroid
53
What is MEN2A triad?
Parathyroid, Phaeochromocytoma, Medullary thyroid
54
What is Addison's disease?
Primary adrenal insufficiency
55
Addison's disease - sodium level?
Low
56
Addison's disease - potassium level?
High
57
What is Cushing's syndrome?
Excess cortisol
58
Cushing's syndrome - face appearance?
Moon face
59
First-line test for Cushing's?
Overnight dexamethasone suppression
60
What is Conn's syndrome?
Primary hyperaldosteronism
61
Conn's syndrome - investigation?
Aldosterone:renin ratio
62
Phaeochromocytoma classic triad?
Headaches, hypertension, hyperhidrosis
63
Phaeochromocytoma investigation?
Plasma metadrenalines
64
Treatment sequence for phaeochromocytoma?
Alpha then beta blockade, then cut out
65
Phenytoin toxicity signs?
Ataxia and nystagmus
66
Digoxin toxicity - visual symptom?
Xanthopsia
67
Lithium toxicity level?
≥1.5 mmol/L
68
Theophylline toxicity signs?
Arrhythmias and convulsions
69
Normal calcium range?
2.2-2.6 mmol/L
70
What percentage of calcium is ionised?
45%
71
What percentage of calcium is protein-bound?
50%
72
Primary hyperparathyroidism - calcium level?
High
73
Primary hyperparathyroidism - phosphate level?
Low
74
Primary hyperparathyroidism - PTH level?
High
75
Secondary hyperparathyroidism - calcium level?
Low
76
Secondary hyperparathyroidism - phosphate level?
High
77
Secondary hyperparathyroidism - PTH level?
High
78
Hypercalcaemia symptoms mnemonic?
Stones, bones, groans, moans
79
Hypercalcaemia treatment if >3.0 mmol/L?
IV saline
80
Hypocalcaemia - Chvostek's sign location?
Facial nerve
81
Hypocalcaemia - Trousseau's sign?
Carpopedal spasm
82
Most common renal stone type?
Calcium oxalate
83
Uric acid stones - X-ray appearance?
Radiolucent
84
Staghorn calculi composition?
Struvite
85
Stone management if >20mm?
Percutaneous nephrolithotomy
86
Amylase normal level multiple for pancreatitis?
>10x upper limit
87
More specific pancreatic enzyme than amylase?
Lipase
88
CK-MB indicates damage to?
Cardiac muscle
89
Troponin remains elevated for how long?
3-10 days
90
BNP level that excludes heart failure?
<100
91
BNP level highly sensitive for heart failure?
>400
92
What does PCSK9 do?
Degrades LDL receptors
93
First-line lipid management?
Dietary modification
94
HMG-CoA reductase inhibitor?
Statins
95
Orlistat mechanism of action?
Pancreatic lipase inhibitor
96
BMI threshold for bariatric surgery alone?
>40
97
BMI threshold for bariatric surgery with comorbidity?
>35
98
Vitamin A deficiency causes?
Night blindness
99
Vitamin D deficiency causes?
Rickets/osteomalacia
100
Vitamin K deficiency affects?
Clotting
101
Thiamine deficiency causes?
Beriberi
102
B12 deficiency causes?
Pernicious anaemia
103
Vitamin C deficiency causes?
Scurvy
104
Folate deficiency causes?
Megaloblastic anaemia
105
Iron deficiency causes?
Hypochromic anaemia
106
UK newborn screening tests for?
PKU, hypothyroidism, CF, MCAD
107
Phenylketonuria enzyme deficiency?
Phenylalanine hydroxylase
108
Cystic fibrosis screening marker?
Immune reactive trypsin
109
Sensitivity formula?
TP/(TP+FN)
110
Specificity formula?
TN/(TN+FP)
111
PPV formula?
TP/(TP+FP)
112
NPV formula?
TN/(TN+FN)
113
Diabetes diagnosis - fasting glucose?
>7 mmol/L
114
Diabetes diagnosis - random glucose?
>11.1 mmol/L
115
Diabetes diagnosis - HbA1c?
>48 mmol/mol
116
DKA - pH criteria?
<7.3
117
DKA - glucose criteria?
>11 mM
118
DKA - ketone criteria?
>3 mM
119
DKA - first treatment?
Fluids
120
DKA - insulin rate?
0.1 u/kg/hr
121
HHS - pH criteria?
>7.3
122
HHS - osmolarity criteria?
>320 mOsm
123
HHS - glucose criteria?
>30 mM
124
Hypoglycaemia definition in diabetics?
<4.0 mmol/L
125
Hypoglycaemia definition in non-diabetics?
<2.2 mmol/L
126
C-peptide is marker of?
Endogenous insulin
127
Insulinoma investigation requirement?
Negative sulphonylurea screen
128
Conscious hypoglycaemia treatment?
Glucotabs then sandwich
129
Unconscious hypoglycaemia with IV access?
10% glucose IV
130
Unconscious hypoglycaemia without IV access?
IM glucagon
131
Premature infant GFR maturity age?
2 years
132
Why is hypernatraemia common in neonates?
High insensible water loss
133
Pathological jaundice - timing <24 hours suggests?
Haemolysis or sepsis
134
Pathological jaundice - timing >2 weeks suggests?
Hepatobiliary failure
135
Normal GFR?
120 ml/hr
136
GFR decline per year with age?
1 ml/hr/yr
137
Gold standard GFR measurement?
Inulin clearance
138
Clinical GFR measurement uses?
Creatinine
139
AKI definition - creatinine rise?
>26 within 48h
140
AKI definition - urine output?
<0.5 ml/kg/hr >6hrs
141
Emergency dialysis indications mnemonic?
AEIOU
142
AEIOU stands for?
Acidosis, Electrolytes, Intoxication, Overload, Uraemia
143
CKD stage 3 GFR?
30-59 ml/min
144
CKD stage 5 GFR?
<15 ml/min
145
Most common cause of CKD?
Diabetes
146
CKD causes anaemia due to?
Loss of EPO
147
Haemodialysis frequency?
3x per week
148
Peritoneal dialysis catheter type?
Tenckoff catheter
149
Kidney transplant usual location?
Right iliac fossa
150
Purine catabolism end product?
Urate
151
Purine catabolism pathway?
Purines→Hypoxanthine→Xanthine→Urate
152
Lesch-Nyhan syndrome inheritance?
X-linked recessive
153
Lesch-Nyhan syndrome enzyme deficiency?
HGPRT
154
Lesch-Nyhan syndrome key feature?
Self-mutilation
155
What is α-haemolytic not equal to?
Group A streptococcus
156
GAS stands for?
Group A streptococcus
157
GBS stands for?
Group B streptococcus
158
GAS causes?
Bacterial tonsillitis
159
GBS causes?
Neonatal sepsis
160
60-40-20 rule for body fluid?
60% water, 40% ICF, 20% ECF
161
Intracellular fluid percentage of total volume?
40%
162
Extracellular fluid percentage of total volume?
20%
163
Males vs females water content?
Males have more water
164
Osmolality unit?
mmol/kg
165
Osmolarity unit?
mmol/L
166
Osmolarity calculation?
2(Na+K) + urea + glucose
167
TURP syndrome cause?
Glycine irrigation absorption
168
TURP syndrome irrigant?
Glycine 1.5%
169
True hyponatraemia osmolality?
Low
170
Pseudohyponatraemia osmolality?
Normal
171
Hypovolaemic hyponatraemia urine Na >20 causes?
Diuretics, Addison's
172
Hypovolaemic hyponatraemia urine Na <20 causes?
Vomiting, diarrhoea
173
Euvolaemic hyponatraemia urine Na >20 causes?
SIADH, severe hypothyroidism
174
Hypervolaemic hyponatraemia urine Na >20 causes?
AKI, CKD
175
Hypervolaemic hyponatraemia urine Na <20 causes?
Heart failure, cirrhosis
176
Cirrhosis hyponatraemia mechanism?
Vasodilator accumulation
177
Hypertonic saline concentration?
3%
178
Central pontine myelinolysis risk group?
Malnourished alcoholics
179
Post-surgery hyponatraemia causes?
Over-hydration, stress ADH
180
SIADH clinical volume status?
Euvolaemic
181
SIADH mechanism?
Inappropriate ADH secretion
182
SIADH malignancy cause?
Small cell lung cancer
183
SIADH drug causes?
SSRIs, carbamazepine, PPIs
184
SIADH treatment?
Fluid restriction
185
Demeclocycline mechanism?
Increases ADH resistance
186
Hypernatraemia definition?
>148 mmol/L
187
Hypernatraemia key question?
Why can't patient drink?
188
Hypernatraemia symptoms progression?
Thirst→confusion→seizures→coma
189
Rapid hypernatraemia correction risk?
Cerebral oedema
190
Hypernatraemia management fluid choice?
Not critical, speed important
191
Best hypernatraemia management?
Encourage oral fluids
192
Diabetes insipidus urine:plasma osmolality ratio?
<2
193
Cranial DI treatment?
Desmopressin
194
Nephrogenic DI treatment?
Thiazide diuretics
195
DI water deprivation test duration?
8 hours
196
Normal urine osmolality after water deprivation?
>600 mOsmol/kg
197
Cranial DI response to desmopressin?
Urine concentrates
198
Nephrogenic DI response to desmopressin?
No response
199
Potassium intracellular percentage?
98%
200
Potassium freely exchangeable percentage?
90%
201
Hypokalaemia GI causes?
Vomiting, diarrhoea
202
Hypokalaemia renal causes?
Hyperaldosteronism, diuretics
203
Hypokalaemia redistribution causes?
Insulin, beta-agonists
204
RTA type 1 location?
Distal
205
RTA type 2 location?
Proximal
206
RTA type 4 mechanism?
Aldosterone deficiency
207
Hypokalaemia cardiac effect?
Arrhythmias
208
Hypokalaemia renal effect?
Nephrogenic DI
209
Mild hypokalaemia treatment?
Oral KCl
210
Severe hypokalaemia IV rate?
Max 10 mmol/hr
211
Conn's syndrome investigation?
Aldosterone:renin ratio
212
Hyperkalaemia artefact cause?
Haemolysis
213
Hyperkalaemia transcellular cause?
Acidosis
214
Hyperkalaemia drug causes?
ACEi, spironolactone
215
Hyperkalaemia ECG - second change?
Loss of P waves
216
Hyperkalaemia ECG - third change?
Widened QRS
217
Hyperkalaemia end-stage ECG?
Sine wave
218
Hyperkalaemia insulin dose?
10 units
219
Hyperkalaemia dextrose concentration?
20%
220
Hyperkalaemia nebuliser treatment?
Salbutamol
221
Calcium resonium dose oral?
15g
222
Calcium resonium dose rectal?
30g
223
Digoxin and calcium interaction?
Precipitates arrhythmias
224
H+ and K+ relationship?
Inversely related
225
pH drop 0.1 causes K+ rise of?
0.7
226
Metabolic acidosis compensation?
Hyperventilation
227
Metabolic alkalosis compensation?
Hypoventilation
228
Respiratory acidosis compensation?
Increased renal HCO3
229
Respiratory alkalosis compensation?
Decreased renal HCO3
230
High anion gap causes mnemonic?
KULT
231
Normal anion gap acidosis causes?
Diarrhoea, RTA
232
Metabolic alkalosis causes?
Vomiting, diuretics
233
Respiratory acidosis causes?
Hypoventilation
234
Respiratory alkalosis causes?
Hyperventilation
235
Anion gap calculation?
(Na+K)-(Cl+HCO3)
236
Albumin contribution to anion gap?
Almost entirely
237
Osmolar gap calculation?
Measured-calculated osmolality
238
Elevated osmolar gap indicates?
Abnormal solute present
239
Liver synthetic function markers?
Albumin, clotting factors
240
Hepatocellular damage markers?
ALT, AST
241
Cholestatic markers?
ALP, GGT
242
Transaminitis 1000s causes?
Viral hepatitis, paracetamol
243
ALT>AST suggests?
Chronic liver disease
244
AST:ALT 2:1 suggests?
Alcoholic liver disease
245
Isolated raised ALP >5x causes?
Paget's, cholestasis
246
Low albumin causes?
Liver disease, malnutrition
247
Raised urea x10 causes?
GI bleed, dehydration
248
Average albumin synthesis rate?
200mg/kg/day
249
INR measures?
Prothrombin time ratio
250
Deranged clotting differential?
Warfarin, DIC
251
Bilirubin breakdown product of?
Haemoglobin
252
Conjugated bilirubin metabolised to?
Urobilinogen
253
Urobilinogen renal excretion product?
Urobilin
254
Stercobilin gives colour to?
Faeces
255
Pre-hepatic jaundice urine bilirubin?
Absent
256
Hepatic jaundice urine bilirubin?
Present
257
Post-hepatic jaundice stool colour?
Pale
258
Hepatomegaly smooth margin causes?
Viral hepatitis, obstruction
259
Hepatomegaly craggy border causes?
Metastases, cirrhosis
260
Acute porphyria enzyme - plumboporphyria?
PBG synthase
261
Acute porphyria enzyme - AIP?
HMB synthase
262
AIP skin symptoms?
None
263
AIP diagnosis?
Urinary PBG and ALA
264
AIP first-line treatment?
IV haem arginate
265
AIP precipitants?
Steroids, stress, starvation
266
Hereditary coproporphyria skin lesions?
Blistering photosensitivity
267
PCT most common type?
Yes
268
PCT skin lesion type?
Vesicles
269
PCT diagnosis?
Urinary uroporphyrins
270
Erythropoietic
protoporphyria enzyme deficiency?
Ferrochetolase
271
Hypothalamic-pituitary hormones - GHRH stimulates?
GH
272
Hypothalamic-pituitary hormones - GnRH stimulates?
LH/FSH
273
Hypothalamic-pituitary hormones - TRH stimulates?
TSH and prolactin
274
Hypothalamic-pituitary hormones - dopamine inhibits?
Prolactin
275
CPFT contraindication?
IHD, epilepsy, Untreated hypothyroidism
276
CPFT insulin dose?
0.15 units/kg
277
Adequate cortisol response?
>170 to >500 nmol/L
278
Adequate GH response?
>6 mcg/L
279
TSH normal response?
>5 mU/L
280
LH normal response?
>10 IU/L
281
FSH normal response?
>2 IU/L
282
Microadenoma size?
<10mm
283
Macroadenoma size?
>10mm
284
Pituitary tumour visual field defect?
Bitemporal hemianopia
285
Extreme prolactin elevation level?
>5000 mIU/L
286
Prolactinoma first-line treatment?
Cabergoline
287
Acromegaly gold standard test?
OGTT
288
Acromegaly follow-up hormone?
IGF-1
289
Acromegaly best treatment?
Transsphenoidal surgery
290
Octreotide drug type?
Somatostatin analogue
291
SIADH excess hormone?
ADH
292
SIADH lung cause?
Small cell lung cancer
293
DI types?
Neurogenic, nephrogenic, dipsogenic
294
Subclinical hypothyroidism TSH?
Raised
295
Subclinical hypothyroidism T4?
Normal
296
Sick euthyroid TSH pattern?
Initially raised then low
297
Hyperthyroid medical treatment?
Carbimazole
298
Carbimazole rare side effect?
Agranulocytosis
299
Radio-iodine contraindication?
Pregnancy
300
Thyroid surgery indication?
Pregnancy planned <6 months
301
Pre-surgery thyroid requirement?
Euthyroid
302
Thyroid storm treatment location?
HDU/ITU
303
Graves disease gender predominance?
Female 9:1
304
Toxic multinodular goitre percentage?
30-50%
305
Subacute thyroiditis other name?
De Quervain's
306
Primary atrophic hypothyroidism goitre?
No goitre
307
Hashimoto's thyroiditis cells?
Hürthle cells
308
Riedel's thyroiditis consistency?
Stony hard
309
Higher neoplasm risk factors?
Solitary, solid, young, male
310
Papillary cancer age range?
20-40 years
311
Papillary cancer histology feature?
Psamomma bodies & Orphan Annie eyes
312
Follicular cancer age range?
40-60 years
313
Follicular cancer spread?
Blood
314
Medullary cancer percentage familial?
20%
315
Medullary cancer histology?
Amyloid deposition
316
Anaplastic cancer prognosis?
Die within 1 year
317
Lymphoma risk factor?
Chronic Hashimoto's
318
MEN1 organs?
Pituitary, Pancreas, Parathyroid
319
MEN2A organs?
Parathyroid, Phaeochromocytoma, Medullary thyroid
320
MEN2B organs?
Phaeochromocytoma, Medullary thyroid, Mucocutaneous
321
Addison's worldwide cause?
TB
322
Addison's Europe cause?
Autoimmune
323
SynACTHen test for?
Addison's disease
324
Cushing's disease percentage?
85%
325
Cushing's mnemonic?
CAPE
326
Overnight dex test dose?
1mg
327
Low-dose dex test dose?
0.5mg
328
High-dose dex test dose?
2mg
329
Conn's syndrome hypertension?
Uncontrollable
330
Conn's surgery threshold?
>4cm
331
Phaeochromocytoma pre-op sequence?
Alpha then beta blockade
332
Digoxin antidote?
Digibind
333
Lithium toxicity level?
≥1.5 mmol/L
334
Lithium >3 mmol/L treatment?
Haemodialysis
335
Gentamicin dosing?
Single daily dosing
336
Theophylline half-life in smokers?
4 hours
337
Corrected calcium use?
When low albumin
338
Ionised calcium percentage?
45%
339
PTH bone effect?
Mobilises calcium
340
PTH renal calcium effect?
Increases reabsorption
341
PTH phosphate effect?
Increases excretion
342
1,25-(OH)2-D3 gut effect?
Increases Ca and PO4 absorption
343
Primary hyperparathyroidism adenoma percentage?
80%
344
Secondary hyperparathyroidism cause?
CKD, vitamin D deficiency
345
Tertiary hyperparathyroidism cause?
Prolonged secondary
346
Hypoparathyroidism most common cause?
Post-surgical
347
Pseudohypoparathyroidism mechanism?
PTH resistance
348
Albright hereditary osteodystrophy feature?
inherited pseudohypoparahypothyroidism
Short 4th/5th metacarpal
349
Osteoporosis T-score definition?
<-2.5
350
Osteopenia T-score range?
-1 to -2.5
351
Z-score compares to?
Age-matched control
352
Bisphosphonates mechanism?
Inhibit osteoclasts
353
Hypercalcaemia community cause?
Primary hyperparathyroidism
354
Hypercalcaemia hospital cause?
Malignancy
355
Hypercalcaemia symptoms mnemonic?
Stones, bones, groans, moans, thrones
356
Hypercalcaemia treatment threshold?
>3.0 mmol/L
357
Hypocalcaemia Trousseau's sign?
Carpopedal spasm
358
Hypocalcaemia Chvostek's sign?
Facial twitch
359
Hypocalcaemia ECG change?
Long QT
360
Symptomatic hypocalcaemia threshold?
<1.875 mmol/L
361
Calcium stones percentage normocalcaemic?
Most patients
362
Calcium stones prevention?
Thiazides
363
First-line stone investigation?
CT KUB
364
Stone management ≤5mm?
Conservative
365
Stone management 6-20mm?
Lithotripsy
366
Amylase pancreatitis threshold?
>3x upper limit
367
Lipase pancreatitis threshold?
>3x upper limit
368
CK-MM source?
Skeletal muscle
369
CK-BB source?
Brain
370
Duchenne MD CK level?
>10x ULN
371
Rhabdomyolysis CK level?
Very high
372
ALP bone vs liver differentiation?
Gamma-GT
373
BNP heart failure exclusion?
<100
374
NT-proBNP vs BNP?
More sensitive
375
Troponin measurement times?
6 and 12 hours
376
Troponin specificity at 12-24 hours?
98%
377
CK-MB good for?
Reinfarcts
378
Myoglobin advantage?
Early detection
379
International unit definition?
Enzyme activity measure
380
Lipoprotein density order?
Chylomicron
381
PCSK9 function?
Degrades LDL receptors
382
Anti-PCSK9 example?
Evolocumab
383
Statin mechanism?
HMG-CoA reductase inhibition
384
Familial hypercholesterolaemia inheritance?
Autosomal dominant
385
Familial hypercholesterolaemia genes?
LDL-R, apoB, PCSK9
386
Lomitapide mechanism?
MTP blocker
387
Ezetimibe mechanism?
NPC1L1 inhibition
388
Rimonabant discontinued why?
Suicide risk
389
Roux-en-Y type?
Most efficacious bariatric
390
Fat-soluble vitamins mnemonic?
ADEK
391
Water-soluble vitamin deficiency more common?
Yes
392
Wernicke syndrome vitamin?
B1 (thiamine)
393
Pellagra 3Ds?
Dementia, dermatitis, diarrhoea
394
Pellagra vitamin?
B3 (niacin)
395
Pernicious anaemia vitamin?
B12
396
Scurvy vitamin?
C (ascorbate)
397
Wilson's disease metal?
Copper
398
Haemochromatosis metal?
Iron
399
Crohn's terminal ileum deficiency?
B12, ADKE
400
Coeliac iron deficiency common?
Yes
