Different types of diabetes

Transcription

1 Different types of diabetes How many types of diabetes are there? Many people are familiar with type 1, type 2 and gestational diabetes, but did you know there are a range of other types of diabetes that are just as important? Unfortunately, these rarer types of diabetes are often more difficult to diagnose, leading to misdiagnosis and delays in receiving the best possible care. Let s have a closer look at these rarer types of diabetes and their differing characteristics. Latent Autoimmune Diabetes in Adults (LADA) LADA has been described as a slowly progressing version of type 1 diabetes with some of its characteristics similar to type 2 diabetes. Like type 1 diabetes, LADA occurs when the insulinproducing beta cells in the pancreas are damaged by the body s own immune system, and no longer produce insulin. However, unlike type 1 diabetes, individuals with LADA may not require insulin straight away; insulin requirements only become necessary months or years after diagnosis. Also, individuals diagnosed with LADA are usually over the age of 30, compared to type 1 diabetes where?85% of cases occur in youth <20 years of age. This presenting characteristic together with the fact that their pancreas is still producing some insulin, often leads to the misdiagnosis of type 2 diabetes. In fact, up to 10-15% of adults with LADA are initially misdiagnosed with type 2 diabetes 1 / 5

2 Also, individuals diagnosed with LADA are usually over the age of 30, compared to type 1 diabetes where?85% of cases occur in youth <20 years of age. This presenting characteristic together with the fact that their pancreas is still producing some insulin, often leads to the misdiagnosis of type 2 diabetes. In fact, up to 10-15% of adults with LADA are initially misdiagnosed with type 2 diabetes. Are some people more prone to LADA? Individuals diagnosed with LADA can be lean, normal weight or slightly overweight, but with all cases, the common presentation is significant weight loss at time of diagnosis. Other clues that can give rise to the clinical suspicion of LADA are: - Age >30 years - Body mass index <25kg/m2 - Lack of family history of type 2 diabetes - Personal history of an autoimmune condition e.g. thyroid disease, rheumatoid arthritis - Immediate family history of an autoimmune condition e.g. thyroid disease, rheumatoid arthritis, coeliac disease - Absence of elevated blood lipid levels - Symptoms of increased thirst, increased appetite and the need to urinate frequently Maturity onset diabetes of the young (MODY) MODY is a rare form of diabetes (occurs in 1-5% of diabetes cases) that generally presents before the age of 25. MODY is highly hereditary, and due to abnormal insulin secretion from beta cells in the pancreas. MODY has characteristics resembling both type 1 and type 2 diabetes and is reportedly misdiagnosed in 90% of cases. Doctors may consider a diagnosis of MODY if there is a history of diabetes in successive generations in the family grandparent, parent and child. Up to six different forms of MODY have been identified through genetic testing, and treatment options will vary depending on the type of MODY diagnosed. Secondary diabetes Secondary diabetes occurs as a consequence of another medical condition. 2 / 5

3 Health conditions that may cause diabetes include: Cystic fibrosis a hereditary condition which results in a thick, build-up of mucus in organs such as the lungs and pancreas. The thick, sticky mucus causes scarring of the pancreas, preventing it from producing enough insulin. Approximately 40-50% of adults with cystic fibrosis develop diabetes. Haemochromatosis a hereditary condition resulting in the body absorbing excess iron from food. The excess iron is unable to be removed from the body, leading to accumulation of iron over time, in organs such as the pancreas. Consequently, the amount of insulin produced by the damaged pancreas is affected. It is estimated that between 20-50% of individuals with haemochromatosis have diabetes, with type 2 most commonly diagnosed. It is also referred to as Bronze Diabetes as it may cause darkening of the skin. Chronic pancreatitis a condition where the pancreas becomes inflamed and painful over a long period of time. Diabetes is a common complication of chronic pancreatitis as the amount of insulin produced by the inflamed pancreas is affected. There are a number of causes of chronic pancreatitis including excessive alcohol consumption and gallstones. Polycystic ovary syndrome (PCOS) this hormonal condition occurs in 12-18% of women between late adolescence and menopause. Between 65-80% of women with PCOS present with type 2 diabetes due to insulin resistance, where the insulin is not working effectively. Cushing s Syndrome occurs when the body s tissues are exposed for long periods of time to high levels of the stress hormone cortisol. Cortisol, a naturally occurring hormone is produced by the kidneys. Some people develop Cushing s Syndrome when their own body produces too much cortisol due to a tumour in the kidney, pituitary gland or lung. Other people develop Cushing s Syndrome because they take corticosteroid medications on a long term basis. Corticosteroid medication includes prednisdone for asthma, rheumatoid arthritis and other inflammatory conditions. The consequence of too much cortisol is an increase in blood glucose levels, with the eventual diagnosis of type 2 diabetes. Type 2 diabetes occurs in 3 / 5

4 20-50% of individuals with Cushing s Syndrome. Pancreatic cancer may lead to insulin resistance, where insulin is not working effectively, or in some cases, the pancreas completely loses its insulin producing capacity. Both of these situations may lead to the development of diabetes. If the pancreas has to be removed (pancreatectomy) as part of cancer treatment, this will also lead to diabetes. Drug induced diabetes Drug induced diabetes occurs when the use of a specific medication leads to the development of type 2 diabetes. Drugs which carry a high risk of causing diabetes include corticosteroids (also see section on Cushing s Syndrome) particularly at high doses over long periods of time, antipsychotic agents used for such conditions as schizophrenia and bipolar disorders and immunosuppressive agents used after organ transplant operations, or for other conditions like psoriasis, rheumatoid arthritis and Crohn s disease. Neonatal Diabetes Mellitus (NDM) NDM is a form of diabetes that occurs in the first six months of life. It is a rare condition occurring in only one in 100,000 to 500,000 live births. Infants with NDM do not produce enough insulin, leading to an increase in blood glucose levels. NDM can be mistaken for type 1 diabetes, but type 1 diabetes usually occurs later than the first six months of life. NDM can either be permanent or transient with the latter disappearing during infancy but may reappear later in life. Approximately 20% of infants with neonatal diabetes will also have some developmental delays and epilepsy. Wolfram Syndrome Wolfram Syndrome is a rare genetic disorder with a number of common features including diabetes, vision impairment and deafness. Alstrom Syndrome Alstrom Syndrome is an extremely rare inherited syndrome that has a number of common features including type 2 diabetes. It is thought to affect around 700 individuals worldwide. 4 / 5

5 Read the original article Click here to read the original article. Published in Diabetes SA Living Magazine July 2016, page 32; Author: Susan Bellman CDE APD BPharm. Additional information - Become a Diabetes SA member today - Diabetes: Know Your Type - Invest in your health Article - How diabetes can affect your body Online Learning Program - Get in touch with your health care team 5 / 5