Diabetic Complications
Diabetics need to be concerned about acute and chronic complications of diabetes. In general, it is the chronic complications that do most of the damage. Acute complications result from some extreme abnormality of blood sugar, causing either severe hyperglycemia or hypoglycemia. The initial symptoms of acute hyperglycemia will involve excess urination (polyuria), excess thirst (polydipsia), fatigue, and blurry vision. Chronic complications result from high glucose levels (hyperglycemia) reacting with different tissues of the body.
Acute Complications
- Diabetic Ketoacidosis
- Diabetic Non-Ketotic Hyperosmolar Coma
- Hypoglycemia
Chronic Complications
- Diabetic Retinopathy
- Diabetic Neuropathy
- Diabetic Nephropathy
- Infections
- Cardiovascular Disease
- Gestational Diabetes
- Secondary Diabetes
- Iatrogenic Diabetes
Acute Complications in Diabetes
Hyperglycemia may result in a coma due to the high level of glucagon stimulation, which is a response to low serum insulin levels. Hyperglycemic comas are either diabetic ketoacidosis (DKA) or nonketotic hyperosmolar coma. Hypoglycemic coma results when the patient takes excess insulin relative to what the body needs during eating or exercise.
Diabetic Ketoacidosis
Any disorder that affects the balance between insulin and counter-regulatory hormones can initiate diabetic ketoacidosis. Most patients already have been diagnosed with diabetes before they are diagnosed with DKA. Usually, only older people will have DKA without any prior diagnosis.
Eighty percent of DKA occurs in people with diagnosed diabetes resulting from inadequate insulin or current stress or illness. DKA usually occurs in Type I patients and rarely in Type II patients. Symptoms include rapid respiration, acetone odor on breath, and diffuse abdominal pain. Metabolic acidosis of pH < 7.35, blood sugar levels of more than 250 mg/dl, and ketones in urine or blood are diagnostic of DKA.
The most common causes of DKA are infections, myocardial infarctions, and emotional stress. Even localized infections, such as urinary tract infections, including prostatitis, can trigger DKA. Prescription drugs, such as corticosteroids and pentamidine, or hormonal changes can also be also be triggers.
The deficiency of insulin and the counter regulatory hormones (glucagons, epinephrine, growth hormone, and cortisol) result in gluconeogenesis in the liver and breakdown of fat (lipolysis), which is the basis of fatty acid breakdown that converts into ketones. The high levels of ketones cause metabolic acidosis.
Prognosis
The prognosis for a young healthy diabetic who is adequately managed is excellent. However, when the patient is old or weak and has other current illness (especially infection), or if the acidosis is very severe, there is significant mortality. If patients with DKA have fallen into a coma or hypothermia, prognosis is poor. In the hospital, electrolytes, bun, creatinine, glucose urinalysis, and electrocardiogram should be ordered. Treatment will mainly consist of IV fluids and insulin bolus of 10 to 20 units IV, followed by a continuous infusion of 5 to 10 units per hour.
Diabetic Coma
Diabetic non-ketotic hyperosmolar (NKH) coma usually only occurs in the elderly. Altered mental status is the main reason that these patients are brought to the hospital. The patient’s blood sugar is consistently very high and alkaline. However, the most distinguishing feature is extreme dehydration caused by frequent urination. Other symptoms include polydipsia, polyuria, and severe dehydration. Laboratory diagnostics reveal hyperglycemia equal or above to 600 mg/dl, hyperosmolarity >320 mOsm/L, arterial pH equal or over 7.3, and the absence of ketones.
Prognosis
Mortality rates are much more severe in NKH coma than in DKA, ranging from 20% to 80%. Rehydration is of utmost importance.
Hypoglycemia
Hypoglycemia in a diabetic is primarily caused by incorrect dosage of insulin or hypoglycemic drugs. It is considered an acceptable complication of drug therapy. However, other factors need to be considered; for example, menstruating women can experience hypoglycemia due to the rapid fall in estrogen and progesterone. Other contributing disorders to hypoglycemia in diabetics include organ failure, hormonal deficiencies, B cell tumor, and hypoglycemia of infancy and childhood.
C-Peptide is the peptide connecting the A and B chains of insulin. It is used to differentially diagnose patients with insulinoma versus factitious hypoglycemia. In hypoglycemic coma induced by an overdose of insulin medication, C-peptides may be lower than normal, while insulin levels are increased. If C-peptide is high, endogenous insulin is produced in high amounts, either from anti-hyperglycemic prescription drugs, such as sulfonylureas, that stimulate the pancreas to produce more insulin or an insulin-secreting tumor. To differentiate between these causes, drug urine tests must be done.
