Chemical Pathology Flashcards
The enzyme expressed by sarcoid lung tissue which causes hypercalcaemia
1a-hydroxylase (= rate limiting step in Vitamin D production!)
Costochondral swelling
Rickets
Looser’s Zones = pseudofractures
Osteomalacia
Colle’s Fracture
Osteoporosis
Band Keratopathy
Hypercalcaemia (calcium deposits on eyes)
Osteitis Fibrosa Cystica
Hypercalcaemia – get brown tumours in bone
Cancer which releases PTHrP
Squamous Cell Carcinoma Lung Cancer
Brown tumours in bone
Hyperparathyroidism (activated osteoclasts form multinucleated giant cells)
Hypercalcaemia in summer only
Sarcoidosis (macrophages in lung express 1α-hydroxylase, but not enough Vit D in winter to activate)
Chvostek’s Sign
Hypocalcaemia = twitch when flick cheek
Trousseau’s Sign
Hypocalcaemia = inflate BP cuff causes carpal spasm
Jigsaw/mosaic pattern in bone
Paget’s Disease (disordered bone remodelling)
Most reliable sign of hypovolaemia in hyponatraemia, which must be done first (before giving fluids)
Low urine Na+ (<20)
Molecule causing vasodilation and low BP in cirrhosis
Nitric Oxide
Tendon Xanthoma
Familial hypercholesterolaemia
Eruptive xanthomas (papules on skin)
Primary Hypertriglyceridaemia
Diabetes
Gross xanthelasma
Primary Biliary Cirrhosis
Monoclonal used in hereditary hypercholesterolaemia
Evolocumab = PCSK9 monoclonal
Diabetes Control and Complications Trial (DCCT)
Type 1 DM: tight control improves outcomes
UK Prospective Diabetes Study (UKPDS)
Takes 15 years to have CVD benefit –> but this benefit lasts 10 years
ACCORD Study
Intensive treatment in older diabetics increases mortality
ADVANCE Study
Looser control works better in older people
Drug added to long-term poorly controlled diabetes with ESTABLISHED CVD
Empagliflozin (SGLT2 inhibitor) or liraglutide (GLP-1 agonist)
Breathing type in metabolic acidosis
Kussmaul Breathing (deep laboured)
Diabetes drug causing metabolic acidosis
Metformin (prevents lactase to glucose conversion)
3 definitions of diabetes
- Fasting PLASMA glucose > 7.0mM
- Plasma glucose after GTT > 11.1mM at 2hrs
- HbA1c > 6.5% (48mmol/mol)
Impaired Glucose Tolerance definition
Plasma glucose after GTT 7.8 – 11.1mM at 2hrs
Low blood glucose, but high C-peptide. What test should you do?
Check urine sulphonylurea as could have OD’d on gliclazide (endogenous insulin)
Non-Islet Cell Tumour secrete which hormone, causing hypoglycaemia
IGF-2 (binds to insulin receptors, acting like insulin)
e.g. mesothelioma, fibroblastoma…
Mutation causing congenital hyperinsulinism = hypoglycaemia
Glucokinase activating mutations
Glucocorticoids secreted by which part of adrenal?
Zona fasciculata
Androgens secreted by which part of adrenal?
Zona reticularis
Aldosterone secreted by which part of adrenal?
Zona glomerulosa
Short SynACTHen test
Addison’s Disease (don’t make enough cortisol after given synACTH)
Syndrome which increases risk of phaeochromocytoma
MEN II
High aldosterone and low renin
Conn’s (high aldosterone suppresses JGA –> low renin)
High aldosterone and high renin
Renal artery stenosis
Brown granular casts in urine
Acute Tubular Injury
Crescents in glomeruli
Crescent Glomerulonephritis (Acute Glomerulonephritis)
Disease causing renal failure, with non-blanching purpuric rash
Systemic Vasculitis
Drugs which prevent end-stage renal failure
ACEi
Cause of nephrotic syndrome in kids
Minimal Change Disease – have loss of foot process
Antibodies in Membranous Glomerulonephritis
Antibodies against phospholipase A2
Renal disease with microalbuminuria
Diabetic nephropathy
Beta-pleated proteinaceous sheets deposited in kidneys
Amyloidosis
Protein found in urine of multiple myeloma
Bence-Jones
Crystals in urine after drink antifreeze
Calcium oxalate
Sample blood from this vein to measure levels of illegal drugs
Femoral vein
Which drug cannot be found in hair?
Cannabis (too low levels)
Active metabolite of amitriptyline
Nortriptyline
AST : ALT >2
Cirrhosis
Half-life of albumin
20 days (“important to know this”)
Most important functional test of liver
Prothrombin Time
Tumour marker in liver cancer
AFP
Beri-Beri caused by what deficiency?
B1 (thiamine)
Pernicious anaemia caused by what deficiency?
B12
Glossitis (beefy tongue) caused by what deficiency?
B2
Test of B12 deficiency
RBC Transketolase
Most common co-existing autoimmune condition in hypothyroid
Pernicious anaemia
Condition with:
- Tricuspid and pulmonary stenosis/fibrosis
- Hepatomegaly with large nodules
- Raised urine 5HIAA
Carcinoid Syndrome = tumour in neuroendocrine cells
Colourless urine gets oxidised to purple before reaches the lab
Porphyria (porphyrinogens = colourless –> oxidised very quickly by UV light in urine)
Porphyria with blistering on backs of hands
Hereditary Coproporphyria (HCP)
Light hair and mousy/musky urine odour
Phenylketonuria (PKU)
Deficiency of what enzyme in Phenylketonuria?
Phenylalanine hydroxylase
Metabolic disease causing cot death
MCAD Deficiency
Baby smells of sweaty feet
Isovaleric Acidemia
Urine smells sweet
Maple Syrup Urine Disease
What drug triggers Reye Syndrome?
Aspirin (salicylates)
10yo girl hirsutism, low cortisol, raised ACTH and 17 hydroxyprogesterone
Congenital Adrenal Hyperplasia = lack 21-hydroxylase
Polysplenia and situs inversus
Biliary atresia
Ambiguous genitalia in neonates
Congenital Adrenal Hyperplasia (increased 17-OH progesterone –> increased androgens)
Frontal bossing in kids
Rickets
Caput medusa
Portal HTN (blood goes back down portal vein to umbilicus)
Gilbert’s caused by deficiency in which enzyme?
UDP glucuronyl transferase
Mode of inheritance in Gilbert’s
Autosomal recessive
Rate-limiting step of purine metabolism?
PPRP to 5-phosphoribosyl-1-amine (via PAT)
- PAT under feedback control by ANP and GNP
- HPRT = enzyme which helps make ANP and GNP
Gouty arthropathy, retarded and self-mutilates
Lesch Nyhan Syndrome (X-linked disease –> males born with no HPRT at all)
Gout crystals
Monosodium urate
Name of acute gout
Podagra