Type 1 Diabetes Mellitus


Important points in history


Symptoms + random blood sugar (RBS) >11.1mmol/L (>200mg/dl)
Fasting BS >7mmol/l (126mg/dl)

(Conversion: 1 mmol/l glucose approximately = 18 mg/dl)

In the absence of clear symptoms, diagnostic testing should be repeated on a separate day.

Other rarer types of diabetes:

Treatment consists of

Diabetic Ketoacidosis

Diabetic Ketoacidosis (DKA) =
Hyperglycaemia RBS >15 or 270mg/dl + ketonuria + acidosis

(if blood gas available pH <7.3 or bicarbonate <15 mmol/l)

Important points in history & examination


Relevant Investigations

Acute complications

Management of Diabetic Ketoacidosis

*******Correct acidosis and high blood sugars slowly *******

Give O2 to patients with circulatory impairment or shock

2. Fluid Replacement

Child weighing 20kg on admission in shock in DKA

1 x 10 mls/kg bolus needed to correct shock = 200mls
Maintenance = 1500ml /day (1.5L)
Deficit = 20 kg x 7.5% = 1.5 L

Requirement (over 48 hours) =
Maintenance (1.5 + 1.5) + Deficit (1.5)

4.5 litres/ 48 hours = 94 mls/hr

3. Insulin Therapy

Subcutaneous insulin

When to switch to maintenance insulin therapy: Stop insulin infusion or 2 hourly SC regime when ketosis is resolving, the child is fully alert and oral fluids are tolerated without nausea or vomiting. pH should be > 7.3. The first dose of subcutaneous insulin should be given 1-2 hours before stopping insulin infusion

3. Potassium replacement

Potassium replacement is needed for every child in DKA if they are passing urine. Add KCL to IV fluids (20 mmol to each 500ml bag). If K+ <2.8 or >6, ECG monitoring advisable.

4. Ongoing management

5. Treatment of infection

6. Cerebral oedema

7. Initial maintenance insulin requirements

once DKA has resolved and the child is drinking and eating


Child weighing 36kg

For 0.5u/kg/d total daily dose of insulin = 18 units

(pre breakfast)
(pre evening meal)
Short acting (Soluble) 4 2
Intermediate acting (Lente) 8 4

Long term management of diabetes

Attend Diabetes clinic (Friday morning) once a month when glycaemic control is stable.

At each clinic review the following

1. Investigations

2. Assess for hypoglycaemic awareness and hyperglycaemic symptoms

3. Blood Glucose monitoring

Recommended target blood sugar range:
Before meals: 4-7mmol (72-126mg/dl)
After meals: 5-10mmol/l (90-180mg/dl)
At bedtime: 10mmol (180mg/dl)
At 3am: 5-8mmol/l (90-144 mgl/dl)

Hypoglycaemia = blood glucose <3.9 mmol/l (70mg/dl)

Ongoing insulin requirements

Insulin adjustment

Review blood sugar booklet, HBA1c & symptoms to guide alternation of regime. DO NOT INCREASE INSULIN BASED ON AN ISOLATED HIGH BGL IN CLINIC as this may be a rebound from hypoglycaemia in the middle of the night (Somogyi effect.)

  1. If a pre-meal BGL is always high, the preceding dose of intermediate acting insulin (lente) may be insufficient.
  2. If the pre-meal BGL is always low, the previous dose of intermediate insulin (lente) may be too high.
  3. If a pre-meal BGL is sometimes very high and at other times very low, either insulin, food or exercise are not consistent and should be reviewed.
  4. If the BGL 2 hours after the meal is too high, the previous meal dose of shortacting (regular) insulin may be too low.
  5. If the BGL 2 hours post-meal is too low, the previous meal dose of shortacting (regular) insulin may be too high.
  6. NB the level of blood glucose can rise in the early morning, so care should be taken if increasing the evening intermediate dose as nocturnal hypoglycaemia may go unnoticed which can be dangerous.


HBA1c (glycated haemoglobin) provides information about the average blood glucose levels over the past 2-3 months. The target HbA1c for all age-groups is < than 7.5%. Check HBA1c at least once yearly (ideally 3 times yearly)


Patient education is the cornerstone of good glycaemic control

  1. Importance of regular meals
  2. Avoid refined sugars e.g. Sobo, coke, fanta, any sugar in tea, cakes and biscuits
  3. Encourage complex carbohydrates e.g. cereals and a high fibre diet
  4. Encourage the whole family to adopt this healthy diet


  1. Keep in a cool place (ideally a fridge; if unavailable place insulin in a small clay pot, then place small pot into a larger pot containing water - evaporation of the water will cool the inner pot)
  2. Rotate injection sites to prevent erratic insulin absorption from lipodystrophy. Use the stomach, thighs, buttocks and upper arms

Hypoglycaemia awareness

Sick day rules


Monitor for complications

Consider anti-hypertensives if blood pressure is consistently > 95th centile or > 130/80 mmHg Hypertension


http://www.idf.org/sites/default/files/Diabetes-in-Childhood-and-Adolescence- Guidelines.pdf