The classical picture of the diabetic is a person suffering from severe thirst, who passes abnormally large amounts of urine and loses weight. However, in practice, only about one third of diabetics fit into this picture. Another third are a modified version. Lack of pep and energy, weakness of the muscles, mild thirst and some weight loss are a frequent combination of symptoms. It is relatively common to see persons with real weight loss accompanied by a definite increase in appetite.
Women often complain of pruritus (itch) of the vulval region (at the vaginal opening). This is probably due to an overgrowth of vaginal moniliasis, a fungus infection that seems to flourish in the altered vaginal fluid found in the diabetic. In males, there is sometimes a balanitis – it may come from contracting monilia from an infected vagina. Some males complain of impotence and marked sexual problems arising from this. This is a major problem, and once established, may become an irreversible situation.
Some patients have no apparent symptoms and are discovered by chance during medical examination, or when multichannel blood tests are done as a routine screening measure. About 20 per cent come along with diabetic complications, such as neuropathy, the pain of which can be extreme and persistent. Some are brought to hospital in a diabetic coma; other cases are discovered by eye specialists who detect the typical diabetic retinopathy when the retina, the light-sensitive part of the eye, is examined through the ophthalmoscope.
Occasionally boils and other skin infections are the first signs, which lead to urine tests.
In general, there are probably two main groups of diabetics. Group one: These persons are older, fatter and have mild symptoms with a gradual onset. They are relatively insensitive to insulin, tend to develop ketosis less often, frequently present with complications.
They are “maturity onset” diabetics. Group two: These patients are younger and thinner, are quite sensitive to insulin, are liable to ketosis, and are often referred to as “juvenile onset” diabetics. Examination by the doctor often shows little more. In some cases there may be some muscle wasting. A check is usually made for lens and retinal changes, skin infections, loss of knee or ankle jerks (as may be expected if the nervous system is adversely affected), and the feet are checked for arterial degeneration (as shown by reduced pulses).
The diagnosis may be confirmed in several ways. A simple urine sugar test can be checked with one of the popularly used dip tests, such as Clinistix. This will show if significant glucose is present in the urine.
If there is a positive reaction, it is worth carrying out a blood-sugar test. One single test, taken one to one-and-a-half hours after a normal meal containing at least 50 g of carbohydrate, showing a blood-sugar level over 10.0 mmol/L (over 180 mg per 100 ml) of blood, is diagnostic.
If the diagnosis is in doubt, a glucose tolerance test may be performed. This checks the blood-sugar levels half hourly for two to two-and-a-half hours after fasting. A graph is usually plotted. If the blood sugar rises to above 10.0 mmol/L (above 180 mg per 100 ml) of blood at half an hour, and does not return to the fasting level within two to two-and-a-half hours, it may be regarded as being diagnostic of diabetes mellitus.
More recent and more accurate tests have been devised and are used in some diabetic centers. The most major advance is use of a test called the glycosylated haemoglobin test that very accurately detects the diabetic and assesses the response to treatment. This will become widely used in time, and may be the method of choice. Other methods will inevitably be developed. Simplified methods of testing the blood for glucose levels are also now widely used both in the doctor’s surgery, as well as by the patient on a regular basis.
These depend on one drop of blood (taken from a fingertip prick) being placed into a so-called reflectance meter and a figure is read from the meter within a few seconds. This accurately gives the blood-glucose level at that moment, and depending on the results, the dose of insulin will vary. Quicker, better and more accurate meters are being constantly developed.