Diabetes mellitus type 1 is a class of diabetes that develops secondary to the autoimmune destruction of the pancreatic beta cells, resulting in an insulin deficiency.
In patients with a clinical picture suggestive of diabetes, the evaluation consists of a thorough personal and family history including a detailed assessment of risk factors. Furthermore, the comprehensive physical exam should focus on cardiovascular, neurologic, and foot findings. Another key component of the workup includes laboratory studies.
Whether the patient is stable or critically ill, a serum glucose test will provide the definitive diagnosis. In the outpatient setting, the fasting blood glucose test is obtained. In the emergency setting, a finger-stick glucose test is measured promptly followed by a serum level. Also, a urine dipstick may reveal glucose.
Criteria for diagnosis
In the outpatient setting, the workup will meet one of the following criteria: 1) fasting plasma glucose value of at least 126mg/dl, 2) HbA1C equal to or greater than 6.5%, 3) a random plasma glucose level of 200 mg/dL or above, or 4) 2 hour plasma glucose value of 200mg/dL or greater in an oral glucose tolerance test (OGTT) [2].
Differentiation between type 1 and type 2 diabetes
These two are distinguished through autoantibody testing and the C-peptide assay.
DKA
Note that when DKA is suspected, this warrants additional labs for confirmation and management of the condition.
In patients with a clinical picture suggestive of diabetes, the evaluation consists of a thorough personal and family history including a detailed assessment of risk factors. Furthermore, the comprehensive physical exam should focus on cardiovascular, neurologic, and foot findings. Another key component of the workup includes laboratory studies.
Whether the patient is stable or critically ill, a serum glucose test will provide the definitive diagnosis. In the outpatient setting, the fasting blood glucose test is obtained. In the emergency setting, a fingerstick glucose test is measured promptly followed by a serum level. Also, a urine dipstick may reveal glucose.
Criteria for diagnosis
In the outpatient setting, the workup will meet one of the following criteria: 1) fasting plasma glucose value of at least 126mg/dl, 2) HbA1C equal to or greater than 6.5%, 3) a random plasma glucose level of 200 mg/dL or above, or 4) 2 hour plasma glucose value of 200mg/dL or greater in an oral glucose tolerance test (OGTT) [2].
Differentiation between type 1 and type 2 diabetes
These two are distinguished through autoantibody testing and the C-peptide assay.
DKA
Note that when DKA is suspected, this warrants additional labs for confirmation and management of the condition.
The earlier the diagnosis, the sooner the initiation of treatment and hopefully the better the short-term and long-term outcomes. Management of these patients requires a multidisciplinary approach best achieved with a medical team consisting of an internist, nephrologist, neurologist, podiatrist, ophthalmologist, diabetic educator, and nutritionist.
Glycemic control
Insulin replacement is the mainstay therapy. There are different types of insulin analogs, which are categorized according to the duration of action. The rapid-acting are typically injected prior to eating and work for a short amount of time. The other main classes include the short-acting type, which can last up to 8 hours and the long-acting form that may last up to a day or more.
There are a variety of insulin analogs in each category that offers a diversified profile of duration, time of onset, and strength. Hence, the clinician can tailor the regimen for each patient with a combination of these preparations.
The patients should meet with a diabetic nurse who will educate them on how to monitor their glucose levels and adjust their insulin levels accordingly. Patients are also taught to match their levels to the food they consume and the exercise they perform.
Note that some patients may be eligible for different therapies. One of these options utilizes an insulin pump, in which the hormone is continuously injected into the blood through a needle placed beneath the skin. The rate of the pump is managed by the patient. Other alternatives include islet cell transplantation or even pancreas transplantation.
Other
A healthy diet is a fundamental component in glycemic control. This can be achieved with the help of a dietician, who will educate the patients and their family members on appropriate meal planning and further details.
Other important factors are physical exercise and smoking cessation.
Complications
Patients with severe complications such as cardiovascular events, renal failure, retinopathy, and peripheral neuropathy will require treatment and management, typically through consultation with specialists in those areas.
Also, DKA is aggressively managed in the emergency setting with the implementation of specific protocol.
Surveillance
Patients with type 1 diabetes should follow up closely with their physician to ensure good glycemic control. Additionally, they should be surveyed for various complications such as the following [2]:
Note that the clinician should consult with the diabetic guidelines that provide comprehensive recommendations for all screening.
The prognosis of type I diabetes is based on how well managed the glucose levels are. Patients with uncontrolled diabetes are at marked risk for kidney failure, blindness, myocardial infarction, stroke, and foot amputations. Hence, strict glucose management may reduce the development of microvascular and macrovascular complications in insulin-deficient patients [11]. Moreover, the American Diabetes Association advises nonpregnant patients to achieve and maintain an HbA1c value of less than 7%.
The predominant cause of mortality and morbidity is cardiovascular disease. Furthermore, DKA is a life-threatening condition that occurs in untreated individuals.
Note that there are massive healthcare costs associated with type 1 diabetes in the United States, which is estimated to be $14.4 billion annually due to medical bills and lost income [12].
Standard risk factors
There are risk factors associated with type I diabetes, which include 1) body mass index equal to or greater than 25kg/m2, 2) having a first degree relative with this disease, 3) Hispanic, African, Native American, Asian American, or Pacific Islander race or ethnicity, 4) history of cardiovascular disease, 5) women with previous gestational diabetes, 6) hypertension, 7) abnormal lipid profile, 8) females with polycystic ovarian syndrome (PCOS), 8) having conditions linked to insulin resistance, and 9) inadequate physical activity [2].
Other risk factors
The cause of this disease is likely multifactorial. Predisposed individuals may develop the disease in conjunction with environmental interplay. For example, congenital rubella syndrome and human enteroviruses are highly linked to type 1 diabetes [3].
Dietary factors such as vitamin D supplementation in infants could be protective [4] but it is not known whether cow's milk or other dietary modifications elevate the risk of developing the disorder [5].
Additionally, there are particular human leukocyte antigen (HLA) gene polymorphisms that are associated with increased risk or protection from type I diabetes mellitus [5]. Moreover, celiac disease and type I diabetes both share the HLA-DQ2 genotype as the former is frequently observed in cases of type 1 diabetes and vice versa [6].
Type I diabetes is implicated in 5% to 10% of diabetics. While the actual number of affected individuals worldwide has not been established, researchers estimate that almost 80,000 children develop type 1 diabetes annually [7].
United States
The annual incidence ranges from 8 to 17 cases per population of 100,000. Additionally, there are approximately 1 to 3 million types 1 diabetics [8].
International
The incidence of this disease depends on the geographical location. For example, it occurs more in Europeans as opposed to Asians. Specifically, the Scandinavian region exhibits a yearly incidence of 35 cases per population of 100,000 while this value is 1 individual per 100,000 in China and Japan. Furthermore, children in Finland are at 40 times greater risk to develop type 1 diabetes that those in Japan.
Autoimmune process
Type I diabetes arises from the autoimmune destruction of pancreatic beta-cells in predisposed individuals. A majority of patients possess autoantibodies to at least one of the following: 1) insulin, 2) glutamic acid decarboxylase (GAD), and 3) islet autoantigen-2 (IA-2) [9].
The subclinical phase lasts for months to years and appears as insulitis or inflammation of the beta cells. Furthermore, hyperglycemia emerges when 80% to 90% of pancreatic beta cells have become damaged.
Type I diabetics may have insulin resistance as well, although this is not a pathogenic mechanism in this form of diabetes.
Metabolic dysfunction
Type I diabetics cannot use the glucose available in the adipose tissues and muscles. Regulatory feedback mechanisms cause the release of glucagon, growth hormone, cortisol, and epinephrine, all of which play a role in hepatic gluconeogenesis, glycogenolysis, and ketogenesis. Hence, these patients develop elevated glucose levels and anion gap metabolic acidosis.
Complications
Chronic hyperglycemia produces microvascular and macrovascular diseases. The former includes peripheral neuropathy, nephropathy, and retinopathy while the latter is comprised of cardiovascular, cerebrovascular, and peripheral vascular disease.
The vascular manifestations result from the effects of long-term hyperglycemia on protein glycosylation, sorbitol synthesis, and free radical production. Elevated serum sugar levels also promote the low-density lipoprotein (LDL) deposition into the arterial wall, which then undergoes inflammation and results in the development of atheroma [10].
Since the risk factors for type 1 diabetes have been studied thoroughly, this gave rise to the Diabetes Prevention Trial–Type 1 (DPT-1) and European Nicotinamide Diabetes Intervention Trial (ENDIT). However, the results have not been promising.
The DPT-1 study in the United States demonstrated that parenteral insulin did not delay or prevent the development of the disease in patients at risk.
The ENDIT investigation, nicotinamide also failed to delay or prevent type 1 diabetes in individuals with family history.
Type 1 diabetes mellitus is an autoimmune disease that targets the insulin-producing beta cells in the pancreas. Diabetes affects multiple organs and systems. In fact, untreated cases lead to severe complications particularly in the progression of the disease. For example, acute events include the potentially fatal diabetic ketoacidosis (DKA). Long-term manifestations encompass cardiovascular disease and events, renal failure, peripheral neuropathy, retinopathy, and foot ulcers.
There are risk factors that are predictive of this disease. Ffamily history, certain races and ethnic backgrounds, as well as physical inactivity are some examples. Furthermore, there may be genetic and environmental factors that play a role in the development of the disease. Additionally, the prevalence of type I diabetes varies according to the country and region.
DKA may be the initial presentation of this autoimmune disease. In others, there are the classic symptoms of polydipsia, polyuria, and polyphagia [1]. Early diagnosis and treatment are paramount to the overall well-being of the individual and the prevention of complications.
Treatment consists of the lifelong replacement of the deficient hormone, insulin. Since type 1 diabetes is a complicated and chronic multisystem disorder, consultation with specialists is paramount. Very importantly, the therapeutic goals include glycemic control, prevention or delaying of complications, and management of these sequelae.
Type 1 diabetes mellitus is a chronic disease in which the body destroys the pancreatic cells that are responsible for making insulin. Insulin is a hormone that allows the cells of the body to remove sugar from the blood, and use it for energy. Since the body cannot make enough insulin, patients with this disease will have very high sugar levels in the blood.
The symptoms may develop rapidly. Patients experience the following:
Some patients become very ill and develop the life-threatening condition called diabetic ketoacidosis. If not treated, they will fall into a coma and possibly die. Symptoms include:
The main treatment is insulin since the body cannot produce it on its own. This medication is typically self-administered through an injection. Another option is the insulin pump, which can directly release insulin from a device through the bloodstream.
There are different types of insulin medications depending on how quickly and how long they act in the body. The doctor and the patient can develop a regimen together using a combination of these types.
Note that diet and exercise are very important to control the glucose levels and allow the patient to remain healthy. A nutritionist will help the patient develop diabetic friendly meal plans. Also, a diabetic nurse will educate the patient on how to monitor the sugar levels and how to adjust the insulin doses according to what they eat and how they exercise. Also, note that smokers are strongly urged to quit.
The patients should be educated regarding how poor control of sugar levels will cause severe complications such as heart disease, heart attack, stroke, kidney failure, damage to the nerves, skin infections, blindness, high blood pressure, elevated cholesterol, etc. Therefore, patients should follow up with the medical team to manage their sugar levels and prevent these from occurring.