DCB Newsletter #1/24: DID YOU KNOW… that there are Rare Types of Diabetes?

Today is 29 February – the rarest day of the year, only occurring every 4 years during a leap year. As rare as this day – or most of the times even rarer – are many diseases which qualify as “rare diseases”. Between 7,000 and 8,000 rare diseases have been identified worldwide and around 300 million people live with at least one [1, 2]. Rare Disease Day was brought to life by advocacy organisations as an opportunity to raise awareness for rare diseases and to call for a human rights priority at local, national and international level.

Now you might be thinking, “That’s great, but what does it have to do with diabetes?”. Most people would perhaps consider diabetes as the opposite of a rare disease when about 537 million people worldwide live with the disease, making it a prevalence of 1 in 10 [3].

However, most outlets usually only cover the most common type 1, type 2 and gestational diabetes. In reality, there are many other types which are considered rare types, and some of them are results of rare diseases. In this newsletter, we want to draw your attention to some of them, to honor all people living with diabetes – no matter how rare the type!

Secondary Diabetes

Rare forms of diabetes are often classified as “secondary diabetes”, meaning that the manifestation of diabetes is the result of another disease or medication [5]. There are different types, induced by either genetic mutations, different syndromes or medications such as steroids [5].

MODY (Maturity Onset Diabetes of the Young)

MODY is a rare form of monogenic diabetes, caused by a mutation in a single gene. If a parent has it, children have a 50% chance of inheriting it. With only 1-2% of all people with diabetes living with MODY, it is very rare compared to the common types. Because of its rare character, it is estimated that 90% of people are misdiagnosed with either type 1 or type 2 diabetes at first [4]. MODY typically manifests under the age of 25 and treatment does not necessarily require insulin. There are many different subtypes, depending on which gene the mutation occurs in [4].

Cystic Fibrosis Diabetes

As the name suggests, this type of diabetes is a result of the genetic condition Cystic Fibrosis. While people living with Cystic Fibrosis can also develop type 1 or type 2 diabetes, Cystic Fibrosis Diabetes is considered a separate type. It is caused by sticky mucus typical in Cystic Fibrosis scarring the pancreas and damaging the parts responsible for insulin production [6].

Type 3c Diabetes

Type 3c Diabetes is often also referred to as “pancreatogenic diabetes” – it is caused by damage to the pancreas, or its removal [7]. Reasons for the development can thus be an acute or chronic inflammation of the pancreas, pancreatic cancer or other conditions. Type 3c Diabetes can be managed with medication or insulin injection, depending on the extent of pancreatic damage [7].

Alström Syndrome

Alström syndrome is an extremely rare disease, estimated to affect less than 1 in a million [8]. It is a genetically inherited syndrome which affects eyesight, hearing and other parts of the body. As a result of Alström Syndrome, people often develop an insulin resistance and a type 2 diabetes [9].

Wolfram Syndrome

Wolfram Syndrome is a very rare genetic disorder estimated to affect 1 in 160,000–770,000 people [11]. It is often also referred to as “DIDMOAD syndrome” – an acronym for its four most common features Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy and Deafness [10]. The Diabetes Mellitus which comes with this syndrome is different to other types of diabetes and usually manifests during childhood [11]. It is commonly treated with insulin, similar to type 1 diabetes [10].

There are many more subcategories and other genetic disorders that can cause the onset of type 2 or type 1 diabetes, or classify as an entirely different type. To mark Rare Disease Day, we want to hold space for all of these types and the medical diversity within Diabetes Mellitus. Whereas at DCB, we commonly interact with the common types of diabetes, diabetes technologies can benefit all people living with diabetes, regardless of type and pathophysiology. Our aim is to make life easier for all people living with diabetes – including extremely rare forms.

Thanks so much for reading and we’ll provide you with the next episode of this series soon!

[1] Federal Office of Public Health Switzerland: Numerous Rare Diseases and Many People Affected.

[2] Rare Disease Day: What is a Rare Disease?

[3] IDF Diabetes Atlas

[4] Diabetes UK: MODY

[5] Nomiyama T, Yanase T. [Secondary diabetes]. Nihon Rinsho. 2015 Dec;73(12):2008-12. Japanese. PMID: 26666145.

[6] Diabetes UK: Cystic Fibrosis Diabetes

[7] Marshall JD, Maffei P, Collin GB, Naggert JK. Alström syndrome: genetics and clinical overview. Curr Genomics. 2011 May;12(3): 225-35. doi: 10.2174/138920211795677912. PMID: 22043170; PMCID: PMC3137007.

[8] Diabetes UK: Type 3c Diabetes

[9] Alström Syndrome UK: Alström Syndrome

[10] Diabetes UK: Wolfram Syndrome

[11] Urano F. Wolfram Syndrome: Diagnosis, Management, and Treatment. Curr Diab Rep. 2016 Jan;16(1):6. doi: 10.1007/s11892-015-0702-6. PMID: 26742931; PMCID: PMC4705145.

This edition was authored by DCB Digital Communications Specialist Svea Krutisch.