Type 1 Diabetes Flashcards
What is the normal blood glucose range?
- 4.4 - 6.1 mmol/L
What is the physiology of insulin?
*think what cells produce it and function
- B cells of islet of langerhans
- Anabolic hormone
- Increase glucose entry into muscle and adipose
- Increase liver glycogenesis
- Increase lipid synthesis
- Inh. glucose production from liver
- Stimulate protein synthesis, ing protein breakdown
What is the physiology of glucagon?
*think cells producing it and function
- A cells if islets of langerhans
- Catabolic hormone
- Inc. glycogenolysis
- Inc. gluconeogenesis
- Incr. satiety
- Inc. lipolysis
- Inc. ketogenesis
What is T1DM?
- inability to produce/secrete insulin due to autoimmune destruction of the beta-cells in the pancreatic islets of Langerhan.
What is the classic presentation of T1DM?
- polyuria
- polydipsia
- weight loss
What age group is typically affected by T1DM?
- Children (95%)
- Adults (10%)
What are the causes of T1DM?
- Genetics
- HLA-D3 & HLA-D4
- Autoimmune
- anti-Glutamic acid Decarboxylase antibody (GAD)
- Virus
- Coxsackie B virus
- Enterovirus
What other autoimmune diseases is T1DM associated with?
- Graves’ disease
- autoimmune thyroiditis
- Addison’s disease
What hormones counter regulate Insulin?
- Glucagon
- Adrenaline
- Growth hormone
- Cortisol
What is Latent-onset Autoimmune Diabetes in Adults (LADA)?
- a variant of T1DM that occur later in life
- patients who develop diabetes in adult life with associated ketosis, weight loss, low BMI and family history of autoimmune disease
What are the sx of T1DM?
- Polyuria & polydipsia
- Weight loss
- Vomiting
- Lethargy
Signs
- mild-moderate dehydration (dry skin, dry mucous membranes, reduced skin turgor)
- BMI <25
If features go unnotice > can progress to DKA
What are the sx of DKA?
- Confusion
- Moderate-severe dehydration (sunken eyes, prolonged capillary refill time)
- Vomiting +/- diarrhoea
- Abdominal pain
- Decreased urine output
- Reduced GCS
- Coma
- Shock (tachycardia, hypotension)
- Kussmaul breathing (Deep sighing respiration)
What Ix would you order for T1DM?
- Clinically diagnosed + random blood glucose >11
- Refer to endocrinologist within 24hrs if T1DM suspected
- Further Ix
- Bedside (urine dip, random BM, urinary/blood ketones)
- Bloods (FBC, U&E, HbA1c, CRP, cultures)
- Special test (C-peptide, islet cell autoantibodies, GAD autoantibodies)
What are the 3 main insulin regimes used in T1DM?
-
Basal-bolus regime
- use of rapid- or short-acting insulin before meals and a long-acting preparation for basal requirements
-
One, two, or three injections per day regime
- biphasic regime with the use of both short-acting and intermediate-acting insulin
-
Continuous insulin infusion via a pump
- supplies rapid- or short-acting insulin
What are the main targets for blood glucose monitoring?
- On waking: fasting blood glucose 5–7 mmol/L
- Before meals: blood glucose 4–7 mmol/L
- Post meals: test after 90 minutes, blood glucose 5–9 mmol/L
What is the main tx target using HbA1c?
- <6.5%
- monitored every 3-6months
How do you monitor for T1DM Cx?
Diabetic review annually
- assessment of injection site - lipohyertrophy
- Retinopathy: annual screening
- Nephropathy: renal function (eGFR) and albumin:creatinine ratio (ACR)
- Diabetic foot problems: full examination including footwear, monofilament assessment of neuropathy, vascular assessment +/- dopplers.
- Cardiovascular risk factors: primary/secondary prevention strategy with optimisation of blood pressure, lipids, weight, smoking and others
- Thyroid disease: screening blood test
What pt education would you recommend so pt can calculate carbohydrate in each meal and adjust their insulin accordingly?
- Dose Adjustment For Normal Eating (DAFNE)
What are the 2 special circumstances in T1DM mx?
- Honeymoon period
- Sick day rules
What is the Honeymoon period?
- newly diagnosed patients in whom there is residual beta cell function
- can last for weeks to months
- May not need exogenous insulin during this period
What is sick day rules?
- number of recommendations in T1DM with an intercurrent illness
What are the 5 recommendations in sick day rules?
- Continue insulin therapy, alterations may be required, advice from a specialist may be sought
- Increase frequency of blood glucose monitoring
- Consider ketone monitoring
- Maintain good hydration and when possible a normal meal pattern, meals may be replaced by carbohydrate based drinks
- Seek urgent medical attention if unable to tolerate oral intake, drowsy or sustained vomiting
What are the cx of T1DM?
*think acute and chronic
Acute
- Hypoglycaemia
- DKA
Chronic
- Microvascular cx
- Retinopathy, neuropathy, nephropathy, diabetic foot
- Macrovascular cx
- Atherosclerosis
What are the cx associated with retinopathy?
- retinal haemorrhage
- fibrosis
- retinal detachment
Describe the NSC-UK Classification of Retinopathy?
-
Non-proliferative:
- Background (R1): dot and blot haemorrhages, hard exudates, cotton wool spots
- Pre-proliferative (R2): intraretinal microvascular abnormalities (IRMA), venous beading
-
Proliferative:
- Proliferative (R3): new vessels at the disc and elsewhere (NVD, NVE), fibrosis, traction retinal detachment
- Maculopathy: exudates, oedema, NVE
What are the types of neuropathy associated with T1D?
- Symmetrical polyneuropathy
- Mononeuropathy
- Diabetic amyotrophy
- spectrum of disease affecting the lumbosacral plexus leading to symmetrical pain, weakness and wasting in the proximal muscles of the leg
- Autonomic neuropathy
- damage of the autonomic nervous system, which can effect multiple systems
