Type 1 Diabetes Mellitus Flashcards by Leila GROCOTT

hyperglycaemia in type 1 diabetes is a result of what pathophysiology?

Autoimmune condition where insulin-producing beta cells in the islets of langerhan in the pancreas are attacked and destroyed by the immune system - results in partial or complete deficiency of insulin production, resulting in hyperglycemia (because insulin causes cells to take up glucose from the blood)

How well did you know this?

Not at all

Perfectly

what are the classifications of diabetes mellitus?

Type 1 - Type 2 - Hybrid - Other eg. MODY/pancreatic injury - Unclassified - During pregnancy - Type 3C - pancreatectomy

How well did you know this?

Not at all

Perfectly

what are the combined causes of type 1 diabetes?

environmental trigger and genetic risk

How well did you know this?

Not at all

Perfectly

what are the combined causes of type 2 diabetes?

genetic risk and obesity

How well did you know this?

Not at all

Perfectly

what is the name given to autoimmune diabetes that presents later in life?

latent autoimmune disease in adults (LADA)

How well did you know this?

Not at all

Perfectly

can T2DM present in childhood?

yes

How well did you know this?

Not at all

Perfectly

can diabetic ketoacidosis be a feature of T2DM?

yes

How well did you know this?

Not at all

Perfectly

monogenic diabetes can typically present phenotypically as what?

type 1 or type 2 diabetes

How well did you know this?

Not at all

Perfectly

how do we measure insulin?

c-peptide as it is the cleavage product of pro-insulin

How well did you know this?

Not at all

Perfectly

how are pancreatic beta cells destroyed?

Presentation of auto-antigen by antigen presenting cells to autoreactive CD4+ T lymphocytes
CD4+ activate CD8+ lymphocytes
CD8+ travel to islets and lyse beta cells expressing auto-antigen
This is exacerbated by release of pro-inflammatory cytokines
Defects in regulatory T-cells that fail to suppress autoimmunity

How well did you know this?

Not at all

Perfectly

Which allele has the largest effect on risk of type 1 diabetes?

HLA-DR allele (human leukocyte antigen)

How well did you know this?

Not at all

Perfectly

Give 4 examples of environmental factors that could trigger diabetes type 1

enteroviral infections
cow’s milk protein exposure
seasonal variation
changes in microbiota

How well did you know this?

Not at all

Perfectly

what are the symptoms of type 1 diabetes?

polyuria
nocturia
polydipsia
blurred vision
recurrent infections eg. thrush
weight loss
fatigue

How well did you know this?

Not at all

Perfectly

what are the signs of type 1 diabetes?

dehydration
cachexia
hyperventilation
smell of ketones
glycosuria
ketonuria

How well did you know this?

Not at all

Perfectly

lack of insulin leads to which processes?

proteinolysis –> increased amino acids
gluconeogenesis –> increased hepatic glucose output
lipolysis –> increased NEFAs –> beta oxidation —> ketone bodies

How well did you know this?

Not at all

Perfectly

what are the complications of hyperglycaemia?

Acute:

diabetic ketoacidosis

Chronic:

Microvascular –> retinopathy, neuropathy, nephropathy
Macrovascular –> ischaemic heart disease, cerebrovascular disease, peripheral vascular disease

How well did you know this?

Not at all

Perfectly

what could be the complication of insulin treatment?

hypoglycaemia

How well did you know this?

Not at all

Perfectly

what are the options for type 1 diabetes management?

insulin treatment

dietary support/structured educations

technology

transplantation

How well did you know this?

Not at all

Perfectly

what are some examples of short-acting insulin taken with meals?

human insulin (actrapid)

insulin analogue (lispro, aspart, glulisine)

what are some examples of background/basal insulin?

bound to zinc or protamine (neutral protamine hagedorn, NPH)
Insulin analogue (glargine, determir, degludec)

insulin pump therapy involves continuous delivery of which form of insulin? Into which part of the body?

short-acting into the subcutaneous space

how do you use an insulin pump?

programme device to deliver fixed units per hour (basal)
actively bolus for meals

what are the positives of an insulin pump?

Variable basal rates

Extended boluses

Greater flexibility

what dietary advice should you give to those with type 1 diabetes?

adjust dose of insulin with carbohydrate content of food
train for carbohydrate counting
substitute refined carbohydrate foods with complete carbohydrates (low glycaemic index)

How does a closed-loop insulin pump work?

* change in glucose * real-time continuous glucose sensor * algorithm to use glucose to calculate insulin requirement * insulin pump delivers calculated insulin

what is a hybrid closed loop insulin pump?

similar to a closed loop but you must tell it when you want to eat

what are the options for transplantation in type 1 diabetes?

* islet cell transplants from pancreas of deceased donor * transplant into hepatic portal vein * life-long immunosuppression * simultaneous kidney and pancreas transplant (better survival when transplanted with kidneys) * requires life-long immunosuppression

Downsides of transplantation?

* life-long immunosuppression required * risk of rejection * limited availability of donors

which blood tests helps us monitor diabetes control overall?

glycated haemoglobin (HbA1c)

How do we monitor glucose levels?

* capillary (fingerprick) blood glucose monitoring * continuous glucose monitoring (restricted availability)

hbA1c reflects what time period of glycaemia?

last 3 months

what can affect HbA1c?

* erythropoeisis eg. iron, vit B12 deficiency * altered haemoglobin * glycation problems eg. aspirin, vitamin C and E * erythrocyte destruction eg. antiretrovirals, splenectomy, rheumatoid arthritis

what is used to guide insulin doses?

* self-monitoring blood glucose results at home * HbA1c results every 3-4 months

what are 3 acute complications of type 1 diabetes?

1. diabetic ketoacidosis 2. uncontrolled hyperglycaemia 3. hypoglycaemia

what can cause diabetic ketoacidosis?

* presenting feature of new-onset type 1 diabetes * acute illness * missed insulin doses * inadequate insulin doses

what levels of pH, ketones, HCO_3- and glucose constitute a diagnosis of diabetic ketoacidosis?

* pH \<7.3 * ketones increased in blood or urine * HCO_3-less than 15 mmol/L * glucose \> 11 mmol/L

what is the level of glucose that constitutes hypoglycaemia?

\<3.6mmol/L

symptoms of hypoglycaemia

Adrenergic * tremors * palpitations * sweating * hunger Neuroglycopaenic * somnolence * confusion * incoordination * seizures * coma or NON at all

when does someone usually get no symptoms of hypoglycaemia?

with recurrent hypoglycaemia, body becomes unreactive

how do you relieve hypoglycaemia?

glucose administration

when are the 4 times hypoglycaemia becomes a problem?

1. excessive frequency 2. impaired awareness (unable to detect low blood glucose) 3. nocturnal hypoglycaemia 4. recurrent severe hypoglycaemia

what are the risks of hypoglycaemia?

* seizure/coma/death * impacts on driving * impacts on emotional well-being * impacts on day to day function * impacts on cognition

risk factors for people with type 1 diabetes for hypoglycaemia?

* exercise * missed meals * inappropriate insulin regime * alcohol intake * lower HbA1c * Lack of training around dose adjustment for meals

list 5 strategies to support problematic hypoglycaemia?

1. indication for insulin-pump therapy 2. try different insulin analogues 3. revisit carbohydrate counting/structured education 4. behavioural psychology support 5. transplantation

what is used for the acute management of hypoglycaemia?

1. carbohydrates and sugary foods 2. glucogel 3. 20% glucose IV 4. IM injection of glucagon