Diabetes Mellitus

Question 1

how to diagnose type 1

Answer 1

symptomatic: random >11

Question 2

what is type 1

Answer 2

autoimmune
autoAb targeted against beta ells
inadequate insulin secretion

Question 3

presentation of type 1

Answer 3

polyuria
polydipsia
weight loss
DKA
2-6 week history

Question 4

what is impaired fasting glucose?

Answer 4

fasting>6.1

2hr after 75g glucose N/A or <7.8

Question 5

what is impaired glucose tolerance?

Answer 5

fasting<7

2hr after 75h glucose 7.8-11.1

Question 6

what does HbA1c assess?

Answer 6

BM over last 8-12 weeks

Question 7

when is assessing HbA1c inappropriate?

Answer 7

<18
acutely unwell
medication that increases BM
end stage CKD
HIV

Question 8

what is type 2?

Answer 8

insensitivity of body tissues to insulin associated with:
ageing
genetics
obesity
high fat diets
sedentary lifestyle

Question 9

what are some of the signs?

Answer 9

reduced energy
visual blurring
pruritis vulvae/balantis (candida)

Question 10

how is type 2 diagnosed?

Answer 10

HbA1c>48 (6.5%)
fasting >7
OGTT 11.1
symptoms = 1 readings
asymptomatic = 2 readings

Question 11

secondary causes of DM

Answer 11

CF
chronic pancreatitis
pancreatic Ca
cushings
acromegaly
thyrotoxicosis
PCC
glucagonoma
thiazide diuretics
corticosteroids
anti-psychotics
anti-retrovirals
insulin-R abnormalities
mycotic dystrophy
Friedreich's ataxia

Question 12

complication screening

Answer 12

at diagnosis and annually
fundoscopy
nephropathy (albumin, Cr, eGFR)
footcheck (neuropathy)
ischaemia (ABPI)
ulcers
deformities
monitor CV risk

Question 13

what is microvascular disease

Answer 13

specific to DM
small vessels of retina, glomeruli and nerve sheaths affected
symptoms manifest 10-20yrs after diagnosis in young pts
genetic differences in susceptibility

Question 14

diabetic retinopathy

Answer 14

non-proliferative: asymptomatic occurs after 8-10yrs

• micro-aneurysms
• exudates
• haemorrhages
• cotton wool spots (>5=pre prolif)
• — microinfarcts in retina cleared by macrophages in 3-6mo
  proliferative: preceded by widespread non-perfusion
• development of new vessels on optic disc and retina - response to ischaemia (VEGF)
• — aborted attempts at vascularisation
• —-haemorrhage
• —-fibrosis and loss of acuity

Question 15

diabetic maculopathy

Answer 15

more common in type 2
presents with blurred vision
subtypes: focal, diffuse, ischaemic
increased risk of catarcts and glaucoma

Question 16

nephropathy

Answer 16

often due to glomerular disease
15-25 yrs after diagnosis
due to ischaemia resulting from hypertrophy of afferent and efferent arterioles, or due to ascending infection
– as kidneys becomes damaged afferent becomes vasodilated more than efferent –> increase intra-glomerular filtration P –> damage to capillaries
evidence: microalbuminuria (albumin:Cr >3) –> start ACEi
normochromic, normocytic anaemia and high ESR

Question 17

diabetic sensorimotor polyneuropathy

Answer 17

walking on cotton wool
vibration temp and pain lost (deep before superficial)
reduced proprioception
interosseous wasting: high arch + clawing of toes
Charcot’s joint (neuropathic arthropathy)
glove and stocking distribution

Question 18

accelerated macrovascular

Answer 18

DM is a RF for atherosclerosis
2x risk stroke
4x risk MI
50x risk amputation due to gangrene

Question 19

diabetic foot disease

Answer 19

10-15% pts
ischaemia + infection + neuropathy = NECROSIS
autonomic neuropathy may contribute to foot disease through reduction of sweating and dry skin –> more vulnerable to stress damage

Question 20

how does DKA cause dehydration?

Answer 20

increase BM

osmotic diuresis

Question 21

how are ketone bodies formed?

Answer 21

rapid lipolysis 
glucose starved tissues
increase FFA
fatty acetyl CoA (in liver cells)
KB in mitochondria for energy

Question 22

signs of DKA

Answer 22

prostration
Kussmaul respiration
N+V 
abdo pain
confusion

Question 23

diagnosis of DKA

Answer 23

BM>11
KB cap >3, urine >2+
pH<7.35 or HCO2 <15

Question 24

what is HHS

Answer 24

characteristic of type 2
dehydration
stupor coma seizures
evidence of underlying illness

Question 25

HHS precipitating factors

Answer 25

consumption of glucose rich meal
thiazides
steroids
beta blockers
infection/MI

Question 26

diagnosis of HHS

Answer 26

osmolality 280-295
HHS >320

2(Na) + urea + BM

Question 27

hypoglycaemia cut off

Answer 27

<3

Question 28

signs of hypo

Answer 28

sweating
anxiety
hunger
tremor
palpitations
confusion
drowsiness
coma
seizures

Question 29

in response to hypo what happens

Answer 29

alpha cells - glucagon
glycogenolysis
gluconeogenesis
inhibit of glycogen synthesis

Question 30

causes of hypo

Answer 30

insulin increase
low glycogen
pit insufficiency (low GH, ACTH)
adrenal insufficiency
non-pancreatic neoplasms
insulinoma
MEN1

Question 31

hormones involved in increasing BM

Answer 31

glucagon
adrenaline
GH
cortisol