Diabetes Mellitus synopsis

Diabetes Mellitus introduction

Diabetes mellitus is a collection of internal body function disorders of carbohydrate build-up and breakdown in which glucose is under-utilized, thereby producing increased glucose in the blood known as hyperglycemia. It is different from diabetes insipidus.

There are individuals who may experience acute life-threatening hyperglycemic episodes, such as keto-acidosis (production of ketone bodies from excessive breakdown of fatty acids) or hyperosmolar coma.

Classification of Diabetes Mellitus

Diabetes diagnosis criteria were modified in 1979, where two major forms of diabetes were recognized. There are type I diabetes mellitus; which involves insulinopenia (a deficiency of insulin), because of loss of pancreatic islet B-cells and depend on insulin treatment to sustain life and prevent ketosis, and type II diabetes mellitus has no bearing on insulin activity.

You might have heard the term “juvenile-onset” diabetes and adult-onset diabetes, both were abolished based on the afore mentioned classification.

Gestational Diabetes Mellitus

This is a carbohydrate intolerance observed during pregnancy. Women with diabetes who become pregnant are not part of this category.

Other specific types of Diabetes Mellitus

There are subclasses of Diabetes Mellitus, where glucose level is high in blood circulation;

1. Genetic defects of B-cell function
2. Genetic defects in insulin action
3. Diseases of the exocrine pancreas
4. Endocrinopathies (e.g., Cushing disease, acromegaly, glucagonoma)
5. The administration of hormones or drugs known to induce B-cell dysfunction (e.g., Dilantin and pentamidine) or impair insulin action (e.g., glucocorticoids, thiazides, and B-adrenergics)
6. Infections
7. Uncommon forms of immune-mediated diabetes
8. Other genetic conditions (e.g., Down syndrome, Klinefelter syndrome, and porphyria)

Signs and symptoms

The following symptoms and signs are associated with diabetes mellitus

Type I

• Polyuria (frequent urination)
• Polydipsia
• weight

Type II

• Most patients are over 40years and obese.
• Candidal vaginitis in women
• Hypertension
• Dyslipidemia
• Atherosclerosis

Diagnosis

The diagnosis of diabetes Mellitus depends purely on the demonstration of hyperglycemia.

Type I diabetes, the diagnosis is usually easy because hyperglycemia.

For type I diabetes, the diagnosis is usually easy because hyperglycemia (1) appears abruptly (2) is severe (3) is accompanied by serious metabolic derangements.

Type II diabetes may be difficult to diagnose because the metabolic changes are often not severe enough for the patient to notice symptoms of them.

Any of the following diagnostic:

1. Classic symptoms of diabetes and casual plasma glucose concentration ≥200 mg/dL (11.1 mmol/L)
2. Fasting plasma glucose ≥126 mg/Dl (7 mmol/L)
3. 2-hour post-load plasma glucose concentration ≥200 mg/dL during the OGGTT (11.1 mmol/L)

IMPAIRED FASTING GLUCOSE

Fasting plasma glucose between 100 and 125 mg/dL (6.1 and 7.0 mmol/L)

IMPAIRED GLUCOSE TOLERANCE

Two criteria be met:

1. Fasting plasma glucose <126 mg/dL (7 mmol/L)
2. 2-hour OGTT plasma glucose concentration is between 140 and 199 mg/Dl (7.8 and 11.1 mmol/L)

GLYCATED HEMOGLOBIN (HEMOGLOBIN A₁) MEASUREMENT

Glycated Hemoglobin has been firmly established as an index for long-term blood glucose concentrations and a measure of the risk for the development of complications in patients with Diabetes Mellitus. Hemoglobin becomes glycated by ketoamine reactions between glucose and other sugars and the free amino groups on the α and β chains of the Hemoglobin in red blood cells. There are different types of glycated Hemoglobin but the one involved in this glycation that has bearing on diabetes Mellitus, is the Hemoglobin A₁C. This Hemoglobin A₁C fraction is abnormally high in diabetic patients with chronic hyperglycemia. Since hemoglobin circulates within the red blood cells whose life span lasts up to 120 days, they generally reflect the state of glycemia over the preceding 8-12 weeks.  Thereby providing an improved method of assessing diabetic control.

SERUM FRUCTOSAMINE

Serum fructosamine is formed by nonenzymatic glycosylation of serum proteins (predominantly albumin). Since serum albumin has a much shorter half-life than hemoglobin, serum fructosamine generally reflects the state of glycemic control for only the preceding 1-2 weeks.

TREATMENT OF DIABETES MELLITUS

1. Diet
2. Medications for treating hyperglycemia
3. Insulin
4. Transplantation of the pancreas

Details of treatment measures in other publications.

References

CURRENT Medical Diagnosis and Treatment 2013 Papadakis et. al.

TIETZ Fundamentals of Clinical Chemistry Burtis et. al.