Makindo Medical Notes

💉 Type 1 Diabetes Mellitus (T1DM) = autoimmune destruction of pancreatic ß-cells 🧬 → insulin deficiency → hyperglycaemia. Patients require lifelong insulin to prevent diabetic ketoacidosis (DKA ⚠️).

📖 About

• Autoimmune destruction of ß-cells → insulin deficiency.
• Daily physiological insulin production = ~16–24 units/day.
• Insulin is essential for glucose + potassium uptake into cells.
• Deficiency → hyperglycaemia, ketosis, DKA ⚠️.
• Lifelong exogenous insulin required.

🧬 Aetiology

• Autoimmune attack on islet ß-cells (HLA-DR3, HLA-DR4 association).
• T-cell mediated destruction.
• C-peptide = marker of endogenous insulin (low in T1DM).
• Autoantibodies: GAD, ICA, IAA (useful in LADA diagnosis).

🩺 Clinical Presentation

• Classic triad: Polyuria 🚽, polydipsia 💧, weight loss ⚖️.
• Blurred vision 👁️, recurrent candidiasis 🍞.
• DKA: ketotic breath, Kussmaul breathing, abdominal pain.

📊 Blood Glucose Ranges (UK vs US)

⏳ Complications

• Microvascular 🩸: Retinopathy, nephropathy, neuropathy.
• Macrovascular ❤️: IHD, stroke, PVD.
• Other: Foot ulcers 🦶, infections, cataracts, gastroparesis.
• Psychological: Depression, anxiety.

🔎 Investigations

• Islet autoantibodies: ICA (~80%), GAD (~90%).
• Low/absent C-peptide.
• HbA1c for monitoring control.
• Baseline: FBC, U&E, lipid profile, ECG, retinal photography.

🛠️ Management

• All require insulin 💉 (no role for oral monotherapy).
• Lifestyle: diet, exercise, smoking cessation, weight management.
• Education: sick day rules, carb counting, hypo awareness.
• "Honeymoon period": temporary recovery of ß-cell function with lower insulin needs.

💉 Insulin Regimens

• SC injections at rotating sites to prevent lipohypertrophy.
• Twice-daily mixed insulin: Intermediate + soluble.
• Basal-bolus: Long-acting basal (50–60%) + rapid-acting with meals (preferred).
• Insulin pump: For patients with HbA1c >7.5% despite basal-bolus regimen.
• Acute illness: Continue insulin (never stop), adjust doses; IV insulin if unable to eat or in DKA.

📚 Case Example

👦 A 14-year-old boy presents with polyuria 🚽, weight loss ⚖️, and abdominal pain. On exam: Dehydrated, Kussmaul breathing, ketotic breath. Capillary glucose: 28 mmol/L, ketones positive, pH 7.1. ✅ Diagnosis: Diabetic ketoacidosis in new-onset Type 1 DM. 🛠️ Management: IV fluids, IV insulin, potassium monitoring, later long-term insulin regimen.