This document discusses diabetes mellitus (DM), a metabolic disorder characterized by hyperglycemia resulting from insufficient insulin. DM can lead to complications affecting the eyes, kidneys, and nervous system, and is a major cause of blindness, renal failure, heart attacks, and stroke. There are two main types of DM - type 1 is immune-mediated and type 2 is often associated with obesity. Diagnosis involves blood tests measuring glucose levels, and management focuses on diet, exercise, and drug treatment to control blood sugar and minimize complications.

1. DIABETES MELLITUS
©2011
Department of Biochemistry
Lumbini Medical College & Research Centre

2. Introduction
 DM is a metabolic disorder characterized by hyperglycemia
resulting due to insufficient of insulin.
 The complication of diabetic affect the eye, kidney and nervous
system.
 Diabetes is a major cause of blindness, renal failure, heart
attacks and stroke.
Greek word:- Diabetes : A siphon or running through;
Mellitus : sweet

3. Sign and symptom
• Hyperglycaemia
• Glycosuria and polyuria
• Polydypsia
• Polyphagia
• Weight loss
• Delayed wound healing
• Ketosis

4. Classification
According to WHO recommendation, 1999:
 Type 1 Diabetes Mellitus
• Immune mediated and
• idiopathic
 Type 2 Diabetes Mellitus
• obese
• non-obese
• maturity onset diabetes of young
 Diabetic prone states
• Gestational diabetes mellitus

5. • Impaired glucose tolerance
• Impaired fasting glycaemia
 Secondary to other known causes
• Endocrinopathies
• Drug induced
• Pancreatic diseases

6. Comparison of type 1 and 2 diabetes
Feature Type 1 diabetes Type 2 diabetes
Onset Sudden Gradual
Age at onset
Any age
(mostly young)
Mostly in adults
Body habitus Thin or normal Often obese
Ketoacidosis Common Rare
Autoantibodies Usually present Absent
Endogenous insulin Low or absent
Normal, decreased
or increased
Concordance
in identical twins
50% 90%
Prevalence Less prevalent
More prevalent
-

7. Diagnostic criteria
1. If the fasting plasma sugar > 126 mg/dl.
2. If 2-hr post glucose load value of OGTT > 200 mg/dl.
3. If both are above these levels, on the same occasion.
4. If symptoms of hyperglycemia and random plasma
sugar level > 200 mg/dl, on more than one occasion
5. Glycated hemoglobin (HbA1C) ≥ 6.5%

8. Metabolic Derangements
Carbohydrate Metabolism
 Net effect is an inhibition of glycolysis and stimulation of
gluconeogenesis leading to hyperglycemia
Lipid Metabolism
 fatty Liver
 ketogenesis
 hyperlipidemia
Protein Metabolism
 muscle wasting

9. Acute Metabolic Complications
 Diabetic Keto Acidosis
• Metabolic acidosis
• Reduced buffers
• Smell of acetone
• Osmotic diuresis
• Sodium loss
• High potassium
• Dehydration
• Coma
 Hyperosmlar Nonketotic Coma
 Lactic Acidosis

10. Chronic Complications
 Vascular Diseases
 Atherosclerosis
• In cerebral vessels – paralysis
• In coronary artery – myocardial infarction
• In small vessels – microangiopathy
 Complications in Eyes
• Cataract of lens
• Retinopathy and blindness
 Neuropathy
• Peripheral neuropathy with paresthesia is very common

11. Normal
Persons
Criteria for
diagnosing
diabetes
Criteria for
diagnosing IGT
Fasting
1 hr ( peak )
after glucose
2 hr after
glucose
<110 mg/dl
< ( 6.1 mmol/L )
< 160 mg/dl
< ( 9 mmol/L )
< 140 mg/dl
< (7.8 mmol/L )
>126 mg/dl
>( 7.0 mmol/L )
Not prescribed
>200 mg/dl
> (11.1 mmol/L )
110 to 126
mg/dl
Not prescribed
140 to 199 mg/dl
Laboratory Investigations
 Random blood sugar estimation
 Oral glucose tolerance tests

12. Oral Glucose Tolerance Test ( OGTT ):
• A well – standardized test, and is highly useful to
diagnose diabetes mellitus in doubtful cases
• Indications
1. Past history of obesity.
2. During pregnancy, excessive weight gain, past
history of miscarriage
3. Family history of DM and to rule out benign renal
glycosuria

13. Contra-indications:
1. With conformed diabetes mellitus
2. In follow up of diabetes
3. In acutely ill patients

14. Preparation of Patients:
1. Instruct the patient to have good carbohydrate diet for
3 days prior to test.
2. should avoid drugs likely to influence the blood
glucose levels, for atleast 2 days prior to test
3. should abstain from smoking during the test
4. strenuous exercise on previous day should be avoided
5. should not take food after 8 PM the previous night.
Should not take any breakfast

15. Method / Procedure of the test:
 Glucose tolerance test should be done with overnight
fasting.
 Fasting blood sample is collected and urine sample is
also obtained. This is denoted as 0 hr sample.
 75 gm of anhydrous glucose ( 82.5 g of glucose
monohydrate ) in 250-300 ml water is given to patient
slowly orally.
 For children glucose dose is adjusted as 1.75 g/kg of
body weight

16.  five sample of blood and urine sample is collected in
interval of half hour for next two and half hour
 total six blood sample including 0 sample are analyzed
for blood sugar and urine sample is detected for sugar
qualitatively
 In Present, WHO recommendation is to collect only
fasting and 2 hour post-glucose load samples of blood
and urine.

17. Interpretation
• Impaired Glucose Tolerance
• Impaired Fasting Glycemia
• Gestational Diabetes Mellitus
• Alimentary Glucosuria
• Renal Glucosuria

18. Factors Affecting GTT
1. Insulin level
2. Carbohydrate starvation
3. Exercise
4. In liver disease
5. In acute infections
6. In thiamine deficiency
7. In hyperthyroidism

19. Monitoring the Diabetic Patient
 Periodic check of blood glucose
 Glycated Hemoglobin

20. Management of Diabetes Mellitus
 Diet and Exercise
 Drugs

21. Did You Know...
• People who can strictly control their blood sugar
levels may be able to minimize or delay diabetes
complications.
• Many people have type 2 diabetes and are not
aware of it.