Clinical Evaluation

A patient who reported to the doctor, because he/she suspects he/she has diabetes mellitus, will be clinically evaluated by the doctor. Some of the questions he will ask history of frequent and heavy urination, excessive thirst, and loss of weight despite eating heavily. The patient may feel weak and fatigued and the patient’s vision may be blurred. These features are useful if the patient is reporting to the doctor for the first time.

If the patient is very young, type 1 diabetes mellitus usually is suspected. Type 1 diabetes is a type of diabetes due to the deficiency of insulin secretion by the pancreas and requires insulin for treatment.

A new case of type 1 diabetes mellitus may present in an emergency crisis (ketoacidosis). After management, the patient recovers and may show very few signs and symptoms until months later when the symptoms relapse. However, most cases present with symptoms and signs of diabetes.

Diagnostic Evaluation of Diabetes

Diagnostic criteria for diabetes mellitus include the following

• Blood Glucose Testing

1. A fasting plasma glucose level ≥ 126mg/dl
2. A 2-hour plasma post-prandial glucose level of ≥ 200mg/dl during a 75g oral glucose tolerance test (OGT)
3. A random plasma glucose ≥ 200mg/dl in a patient with classic symptoms of hyperglycemia

• Lab Studies: All fingerstick glucose tests using a glucometer are appropriate for virtually all patients with diabetes mellitus. Their glucose levels must be confirmed in serum plasma to make the diagnosis, and this is done in the laboratory.

It is recommended that HbA1C should be done in the laboratory for diagnosis of type 1 diabetes only when the condition is suspected, but the classic symptoms are absent. HbA1c of 7% confirms the diagnosis of diabetes mellitus.

• Screening: Screening of type 1 diabetes in asymptomatic low-risk individuals is not recommended. However, in patients at high risk (those who have first-degree relatives with type 1 diabetes) it may be appropriate to perform annual screening for anti-islet antibodies before age 10, along with 1 additional screening during adolescence.

Type 2 Diabetes Mellitus

This usually affects adults and sometimes older adolescents. Most patients are asymptomatic for years, and so do not seek early medical attention because of the insidious nature of the disease. They may therefore present when diabetes has been present for a long time and has started developing complications such as visual difficulties from retinopathy or pains and tingling in the lower limbs from neuropathy. To prevent this, an annual comprehensive medical examination should test for the presence of diabetes mellitus with random blood sugar or HbA1C.

Established Diabetes Type 1

In patients with established diabetes mellitus type 1, a focused history should include the following questions

1. Is diabetes generally well controlled? Poor control of infectious and poor wounds really increases the risk of diabetes
2. Does the patient have severe hypoglycemic reactions and risk of losing consciousness? This is important especially if the patient drives a car
3. Does the patient have kidney damage from diabetic nephropathy? This is important because it may alter the use of medications or intravenous contrast materials.
4. Does the patient self-monitor his or her blood glucose level?
5. When was the patient’s HbA1C value last measured? What was it?
6. Time, date, and frequency of testing and actual level are important

Diabetes Testing in People Undergoing Routine Medical Tests

A routine diabetic test should be done in people who are at risk i.e., those

1. Who are overweight or obese
2. Who are having physical inactivity
3. Who have first-degree relatives who are diabetic
4. Women who delivered a baby weighing over 9lb
5. Who have hypertension B.P greater than 140/90
6. Who have very high cholesterol and triglycerides
7. Who has cardiovascular disease or history of cardiovascular disease