Diabetes mellitus

Diabetes Mellitus
Etiological Classification
I. Type 1 diabetes (absolute insulin deficiency)
II. Type 2 diabetes (Insulin resistance or insulin secretary defect)
III. Other specific type of diabetes
A. Genetic defects
B. Disease of exocrine pancreas-pancreatitis
C. Endocrinopathies –Cushing’s syndrome
IV.Gestational Diabetes Mellitus
Clinical features
Polyuria
Nocturia
Enuresis (children)
Thirst and dry mouth – Polydypsia
Polyphagia (Hyperphagia)
Systemic symptoms – tiredness, malaise, lack of energy and muscular weakness, irritability
Recent change in weight
Blurring of vision
Nausea and headache
Infections – Pruritis vulvae, Balanitis, Pyogenic skin infections and urinary tract infection
* The classical triad of thirst, polyuria, nocturia, and rapid weight loss are prominent in type 1 but are often absent in type 2
* Type 2 pts – overweight with truncal obesity, hypertension (50%)

Approach to a patient
1) History;
Symp of Hyperglycemia → polyuria, polydypsia, polyphagia, wt loss, fatigue, blurry vision, frequent sup inf and slow healing of skin lesions after minor trauma
DM relevant aspects → family history, co-morbidities (CV, HT, DL), prior medical conditions, exercise, smoking and alcohol
Established DM → prior Diab care, type of therapy, prior HbA1c levels, frequency of Hypoglycemia, presence of DM complications
2) Physical examination;
(a) General - body habitus/fat distribution
- dry mouth/dehydration
- air hunger, skin pigmentation, dermopathy, skin or mucosal sepsis
- BMI > 30 kg/m2
- Weight : Hip
(b) Head - Xanthelasma, cranial nerve palsy/eye movements/ptosis
(c) Eyes - visual acuity, cataract, fundoscopy
(d) Neck - carotid pulse, bruits, thyroid enlargement
(e) Axilla - Acanthosis nigricans
(f) Abdomen - hepatomegaly
(g) Insulin inj sites - ant abdominal wall, upper thighs/ buttocks and upper outer arms (lipodystrophy,lipohypertrophy)
(h) Blood pressure
(i) Hands - Dupuytren’s contracture
- Carpal tunnel syndrome
- trigger finger/thumb
- limited joint mobility, wasting of small muscles, sensory abnormality
(j) Legs - muscle wasting & sensory abnormality
- Granuloma annulare
- hair loss
- tendon reflexes
- Necrobiosis lipoidica
(k) Feet - loss of plantar arch, clawing of toes (neuropathy), localised infection, discolour of skin (ischaemia)
- deformity (Charcoat neuroarthropathy)
- peri pulses, skin temp, capillary refill
- sensation and reflexes (plantar & ankle)
Investigations
A) Urine;
- Glucose - Urine dipstick test
- Benedict’s test
- Ketones - Nitroprusside reaction
Protein
B) Blood;
- Random blood glucose
- OGTT - Fasting blood glucose
- 2hr post prandial glucose
- Glycated haemoglobin
Plasma fructosamine

EMERGENCY COMPLICATIONS

Diabetic Ketoacidosis
Major medical emergency that develops when insulin stores are depleted, principally in people with type 1 diabetes.

Pathogenesis:
-Trigerred in insulin-deficient patients by a stressful event, most often
respiratory or urinary tract infectios.
-Alcohol abuse, physical injury, pulmonary embolism, heart attack etc.
-Low insulin cause hyperglycemia which leads to osmotic diuresis leading
to dehydration and electrolyte loss.
-Fat breakdown accelerates and increase fatty acids production which
is then converted to ketone body.
-Resulting metabolic acidosis force hydrogen ions into cells and displacing
potassium ions.

Symptoms:
-Polyuria, thirst
-Weight loss
-Weakness
-Nausea and vomiting
-Leg cramps
-Blurred vision
-Abdominal pain

Signs:
-Dehydration
-Hypotension (postural or supine)
-Acetone breath
-Hypothermia
-Confusion, drowsiness, coma
-Kussmaul breathing
-Tachycardia

Investigation:
-Urea and electrolytes, blood glucose, plasma bicarbonate
-Arterial blood gas for plasma bicarbonate and hydrogen ion concentration
-Urinalysis for ketones
-ECG
-Infection screening

Management:
-Admit to hospital preferably in ICU
-Fluid replacement:
-0.9% saline (NaCl) i.v 1 litre over 30minutes, 1 hour, 2 hours and
next 2-4 hours.
-When glucose level < 15mmol/l, switch to 5% dextrose 1 litre
8th hourly.
-Insulin:
-50 unites soluble insulin in 50ml 0.9% saline i.v. via infusion pump
-6 units/hr initially, 3 units/hr when glucose < 15mmol/l and 2
units/hr when glucose < 10mmol/l.
-Aim to reduce blood glucose by 3-6mmol/l per hour
-Potassium
-Added potassium in fluid.
-Additional procedurs like catheterisation, nasogastric tube, central
venous line, plasma expander, antibiotic and ECG monitoring based
on severity.

Complication:
-Cerebral oedema, ARDS, thromboembolism, DIC


Non-ketotic Hyperosmolar Diabetic Coma
-Condition characterised by severe hyperglycemia (>50 mmol/l)
without significant hyperketonaemia or acidosis.
-Usually affects elderly patients.
-Mortality is 40%
-Treatment:
-Insulin (3units/hr)
-Calculation of plasma osmolarity 2[Na]+2[K]+[glucose]+[urea]
in mmol/l.
-0.45% saline given if osmolarity >340mmol/kg (normal=280-300)


Hypoglycemia
Also called as insulin shock, develops when blood sugar levels fall below 3.5mmol/l. Mild hypoglycemia is common among people with type 2 diabetes.

Causes:
-Missed, delayed, inadequite meal
-Excess exercise
-Alcohol intake
-Errors in oral hypoglycemic agent or insuline dose/schedule/administration
-Poor design insulin regimen
-Lipohypertrophy at injection sites.

Clinical Features:
-Mild - Sweating, trembling, hunger, rapid heartbeat, nausea, headache
-Severe - Confusion, weakness, disorientation, coma, seizure, death.

Treatment:
-Oral carbohydrate if recognised early
-Intravenous glucose (30-50ml of 20-50% dextrose)
-Glucagon 1mg IM
-Commercial viscous glucose gel solution over buccal cavity.

Different features of Diabetes:
Though people with diabetes experience many symptoms, the presence of the classical triad of:
1. Being very thirsty.
2. Increased hunger.
3. Having to go to the bathroom very frequently to urinate is virtually diagnostic of diabetes.
In addition following symptoms may also be present:
1. Weight loss.
2. Wounds that don't heal.
3. Extreme unexplained fatigue.

There are two main types of diabetes.

Type 1 (also called juvenile or insulin-dependent) diabetes, this type of diabetes the body stops producing insulin altogether (a hormone that allows your body to use glucose found in foods). As seen with the name, this type of diabetes affects young adults. In addition, people with type 1 diabetes are totally insufficient insulin and must take daily insulin injections to survive.

Type 2 (also called adult or non-insulin-dependent) diabetes, in this type of disease, the body does not produce insulin, but not enough to properly convert food into energy. This form of diabetes usually occurs in people over 40, overweight, and have a family history of diabetes.