Endocrinology - Diabetes Flashcards
Normal fasting glucose levels
Up to 6mmol/L
Impaired fasting glucose levels
6-7mmol/L
Diabetic fasting glucose levels
> 7mmol/L
Pathophysiology T1DM
Autoimmune disease w/ antibodies targeted against B cells –> cell death Inadequate Insulin secretion
PS T1DM (1st ep)
2-6w Hx of
Polyuria
Polydipsia
W loss
Pathophysiology T2DM
Blood levels insulin initially normal
Insulin resistance
Beta cells then decompensate and stop XS insulin production –> hyperglycaemia
PS T2DM
Over m/y
Lack of E
Visual blurring
Pruritis vulvae/balanitis b/c candida infection
PS older pt of T2DM
Retinopathy
Polyneuropathy
ED
Aa disease
Staph skin infections
Hereditary links T1DM
HLA-DR3/DR4
Concordance in twins - T1DM
30-50%
Concordance in twins - T2DM
50%
2’ causes of DM
CF
Chronic pancreatitis
Pancreatectomy
Hereditary haemochromatosis
Carcinoma pancreas
Cushing’s
Acromegaly
Thyrotoxicosis
Phaeochromocytoma
Glucagonoma
Drug induced
Freidreich’s ataxia
Dystrophia myotonica
HbA1c levels diabetic
> 48mmol/L
Pre-diabetic levels HbA1c
42-7mmol/L
Who would using HbA1c be inappropriate in?
<18 y/o
T1DM
Pregnancy
Acutely unwell
Those on meds that raise blood sugars
Any haemolytic disorder
ESRD
HIV
certain drugs
Patients taking which 3 drugs would it be inappropriate to do a HbA1c on
Dapsone
Erythropoetin
Ribavirin
75g glucose load test - normal values
fasting < 7
2 h < 7.8
75g glucose load test - impaired fasting glucose
Fasting 6.1-7
2h <7.8
75g glucose load test - imapired glucose tolerance
Fasting <7
2h 7.8-11
75g glucose load test - DM
fasting <7
2h >11
+ves of HbA1c over glucose tests (3)
Non-fasting
Quicker for patient than GGT
Avoids glucose load
Genetic linkage MODY
Autosomal dominant
When should you suspect T1DM in a patient > 40?
If comorbid autoimmune disease
And BMI <25
Non-medication Mx T2DM (9)
Individualised care plan
Group education programme
Screen - complications
Monitor CV risk
Diet advice
Weight loss (5-10%)
Increase PAL
Stop smoking
Alcohol advice
Alcohol advice for pt w/ DM
Limit intake
Carb containing snack before and after consumption
How to monitor CV risk for pt w/ T2DM
BP control
Qrisk score
Relevance of Qrisk score + T2DM
If 10y risk >10% - offer 20mg atorvastatin
Screening for complications yearly T2DM (3)
Fundoscopy
Nephropathy screen
Foot check
Target HbA1c diabetics
6.5% (48)
1st line Dx regime T2DM
Metformin - 500mg od –> every meal
1st line Dx regime T2DM if metformin isn’t tolerated/CI
Gliptin
Or
Thiazolidinedone
Or
Sulphonylurea
2nd line Dx regime T2DM
Metformin + 2nd Dx
3rd line Dx regime T2DM
Triple therapy
= Metformin
+
Sulphonylurea
+
Gliptin/pioglitazone
Alternative to triple therapy T2DM if metfomin C/I
Insulin regimen
Mode of action Metformin
Decr hepatic glucose prod
Increase peripheral insulin sensitivity
C/I metformin (4)
eGFR 30 or <
Alcoholic
If pt risk lactic acidosis (DKA)
If Pt at risk tissue hypoxia
What must be monitored when on metformin annually
Renal fct
SE metformin (3)
GI Sx
Lactic acidosis
Vit B12 defic
E.g. S acting Sulphonylureas
Tolbutamide
E.g. Med acting Sulphonylureas
Glicazide
E.g. long acting Sulphonylureas
Glibenclamide
Mode of action Sulphonylureas
Increase insulin secretion
Who should Sulphonylureas be prescribed with caution? (2)
Elderly - risk hypoglycaemic events
Obese
SE Sulphonylureas (2)
Norm well tolerated
GI
LIver
E.g. of Thiazolidinediones
Pioglitazone
mode of action Thiazolidinediones
PPARy activators - increase peripheral insulin senstivity
SE Thiazolidinediones (4)
Fl retention
W gain
Liver dysfunction
Bladder cancer
What must be monitored with Thiazolidinediones
LFTs
Who are Thiazolidinediones C/I in ?
CCF
Because of fl retention
E.g. of gliptin
Sitagliptin
Mode of action gliptin
DPP-4 inhibitors
Increase post prandial release
Who to avoid gliptins in?
Cardiac
Hepatic
Renal dysfunction
SE gliptins (2)
GI disturbance
Rarely acute pancreatitis
E.g. of GLP-1 mimetics
Enaxatide
Who qualifies for trial of GLP-1 mimetics ?
If BMI >35
Or <35 + Other co-morbidities/insulin therapy would have negative occu impacts
SE GLP-1 mimetics (2)
GI
Rarely acute pancreatitis
DAFNE
Dose adjusted for normal eating
Aim of short acting insulins
Mimic bodys insulin secretion in response to food
E.g. of rapid acting short acting insulins (2)
humalog
Novoramid
When are rapid acting short acting insulins administered/
with or just after food
Onset of action time rapid acting short acting insulins
15 mins
Duration action rapid acting short acting insulins
2-5hrs
E.g.s of soluble short acting insulins (2)
Actarapid
Humulin S
When are soluble short acting insulins administered?
30 mins before food
Duration of action soluble short acting insulin?
Up to 8 hours
Aim of intermediate acting insulins
Mimic basal insulin secretion
e.g.s of intermediate acting insulins (2)
Humulin I
Insulatard
Onset time intermediate acting insulins
1-2hours
Duration intermediate acting insulins
16-35hrs
Aim of long acting insulins
Mimic basal insulin secretion
E.gs of long acting insulins (4)
Lantus
Levemir
Tresiba
Detemir
Which insulin regime is recommended T1DM? /
Basal bolus
b.d long acting
Rapid acting wih each meal
Insulin regime T2DM
continue metformin Tx
Intermediate acting insulin o.d./b.d.
biphasic preps in HbA1c partic high
Complications of insulin therapy
Weight gain
Insulin resistance
Pain, redness, swelling at injection site
Lipohypertrophy at injection site
injection site abscess
Define ketosis
Elevated plasma ketone levels in absence of acidosis
Which type of diabetic gets DKA
T1DM
3 circumstances under which DKA occurs (3)
Prev undiagnosed DM
Interruption of insulin therapy
Stress of intercurrent
biochemical features DKA (5)
Hyperglycaemia >10
Kertones +ve
HCO3- - low
Plasma Na - usually low
Plasma K+ - high or norm/high
PS DKA (8)
Prostration
Kussmaul resp
N+V
Abdo pain
Confusion/stupor
Coma
Skin dry
Marked polyuria
Ix DKA (7)
U+E
Creatinine
Blood glucose
VBG
ECG
CXR
Pregnancy
How is the severity of DKA determined
pH
mild DKA
pH >7.3
mod DKA
pH 7.1-7.3
severe DKA
pH <7.1
Immediate Tx DKA
A-E
1L 0.9%NaCl over 1hr
IV insulin
How to do the bags of NaCl IV for DKA Tx
bag 1 - 1L over 1hr
bag 2 - 1L over 2hr
bag 3 - 1L over 2hr
bag 4- 1L over 4hr
How to change management for DKA patient after recovery?
–> SC insulin when pt can eat/drink + pH>7.3
Stop IV infusion 1hr after SC starts
Rx to DM team
Which type of diabetes gets HHS?
T2DM
(elderly, usually previously undiagnosed)
Precipitating factors HHS (3)
Consuming glucose rich foods
Meds - thiazide diuretics, steroids, b blockers
Illness - infection/MI
CF HHS (2)
Dehydration
Stupor/coma
Diagnosing HHS (6)
Osm >320
Severe hyperglycaemia (often >40)
Ketones - -ve
HCO3 - -ve
Plasma Na+ - v high
Plasma K+ - norm/high
How to calculate osmolality
2(Na+) + urea + glucose
Mx HHS
Aggressive fl
Low dose fixed IV insulin
Considder K+ replacement
Prophylactic LMWH
How long in HHS can it take for electrolytes to return to normal?
72hrs
Def hypogylcaemia
plasma glucose <3mmol/L
Autonomic Sx - hypoglycaemia (5)
Sweating
Anxiety
Hunger
Tremor
Palpitations
Neuroglycopenic Sx - hypoglycaemia (3)
Confusion
Drowsiness/coma
Seizure
Effect of glucagon (3)
Increase glycogenolysis
Increase gluconeogenesis
Inhibit glycogen synthesis
Adult causes hypoglycaemia with raised insulin (4)
Insulin admin
hypoglycaemia Dx (sulphonylureas)
Insulinomas
Septicaemia
Adult causes of hypoglycaemia without raised insulin (3)
Sever liver/kidney disease
Hormonal + GF tumours
Hypopituitary, hypoadrenalism, low GH
Mx hypoglycaemia - if can swallow
10-20g fasting acting carb
Recheck glucose 10-15 mins
When Sx improve - eat long acting carb
Mx hypoglycaemia - if pt unconscious
1mg IM glucagon immediately
If doesn’t respond in 10 mins - call 999
In hospital - IV 100ml 20% glucose up to 3 times
When is glucagon therapy for hypoglycaemia not effective?
If alcohol has been consumed
Which microvascular structures are particularlya affected in diabetes?
Small vessels of retina, glomeruli and nn sheaths
3 ways in which diabetes can affect the eyes
Diabetic retinopathy
Cataract
External ocular palsies
Symmetrical polyneuropathy - pattern of sensory loss
Glove and stocking
Which aspects of sensory loss are lost first in symmetrical polyneuropathy
Vibration
Deep pain
Temperature
Other PS symmetrical polyneuropathy (4)
Pt losing balace when eyes closed
Walking on cotton wall
Interosseus wasting of small mm feet
Unrecognised trauma w/ poor healing –> ulcers
What neuropathic arthropathy may develop from Symmetrical polyneuropathy
Charcot’s foot
What is acute painful neuropathy?
Painful burning pains in feet, shins and ant thighs
What is acute painful neuropathy associated with?
Poor glycaemic control
At what time of day is acute painful neuropathy worst for patients?
Night
When does acute painful polyneuropathy remit?
After 3-12 m of glycaemic control
What are CN neuropathies occur in pt w/ DM?
III
IV
VI
Which isolated peripheral nn lesions are more common in DM?
Nn compression syndromes e.g. carpal tunnel
Foot drop b/c lesions on sciatic nn
What is mononeuritis multiplex?
When > 1 nn is affected by mononeuropathy
What is diabetic amyotrophy?
Progressive wasting of mm tissues in DM
PS diabetic amyotrophy
Painful wasting, typically of quadriceps mm
Norm middle aged men
Rare
Sympathetic dysfunction - autonomic neuropathy (4)
–>
postural HoTN
Ejaculatory failure
Reduced sweating
Horners syndrome
Parasympathetic dysfunction - autonomic neuropathy (4)
Erectile dysfunction
Constipation
Urinary retention
Holmes Adie pupil
When do renal complications manifest - T1DM
15-25y after diagnosis
What is the leading cause of premature death in young diabetics?
CKD
What % diabetics get nephropathy
30%
Nephropathy testing
ev 6 months - microabuliminuria
What should every pt w/ microalbuminuria be started on
ACEi
Non-diabetic causes of microalbumin
Exercise
UTI/inflamm
Contamination of genital tract
Acute illness - esp fever
Cardiac failure
HTN
Macrovascular complications DM
Incr risk:
Stroke
MI
gangrene