Reply to 'Slowly progressive insulin dependent diabetes mellitus in type 1 diabetes endotype 2'.

This document is a reply to a correspondence on a review about the heterogeneity and endotype of type 1 diabetes mellitus. The authors agree with the correspondents that slowly progressive type 1 diabetes mellitus (SPIDDM) may not necessarily involve obesity or other diabetogenic mechanisms characteristic of type 2 diabetes mellitus. They also note that the definition of SPIDDM may differ in different populations. The relationship between SPIDDM and the endotype referred to as T1DE2 remains unclear, and the authors propose that T1DE2 is the predominant endotype of type 1 diabetes among the adolescent-onset and adult-onset population in Western countries. They also discuss the differences between SPIDDM and fulminant type 1 diabetes mellitus (FT1DM) and the potential role of MDA5 in SPIDDM. The authors agree with the correspondents that a deeper understanding of type 1 diabetes mellitus endotypes is important for effective therapeutic intervention. [Extracted from the article]