# Missed Autoimmune Diabetes: Latent Autoimmune Diabetes in Adults in the Setting of Autoimmune Clustering

## TL;DR

A case study shows how latent autoimmune diabetes in adults (LADA) can be misdiagnosed and how proper diagnosis and insulin therapy can improve symptoms.

## Contribution

Highlights the diagnostic challenges of LADA and its association with autoimmune clustering and systemic symptom improvement with insulin therapy.

## Key findings

- LADA was confirmed by elevated pancreatic autoantibodies in a patient with autoimmune conditions.
- Insulin therapy improved glycemic control and musculoskeletal symptoms.
- LADA should be considered in patients with autoimmune clustering and phenotypic discordance.

## Abstract

Latent autoimmune diabetes in adults (LADA) is frequently misdiagnosed as type 2 diabetes mellitus (T2DM), particularly in older adults, owing to its adult onset, initial insulin independence, and indolent clinical course, resulting in the delayed initiation of insulin therapy. We present a woman in her sixties with Hashimoto’s thyroiditis and a prior diagnosis of Sjögren syndrome who developed progressively worsening hyperglycemia and concurrent rheumatological symptoms, including chronic joint pain and stiffness, despite treatment with multiple noninsulin therapies. Her lean body habitus, absence of clinical insulin resistance, progressive glycemic deterioration, autoimmune background, and musculoskeletal manifestations prompted further evaluation, which revealed markedly elevated pancreatic autoantibodies, including glutamic acid decarboxylase (GAD-65), islet antigen-2 (IA-2), and zinc transporter 8 (ZnT8) antibodies, confirming the diagnosis of LADA with evolving β-cell failure. Transition to insulin-based therapy resulted in excellent glycemic control and was accompanied by substantial improvement in musculoskeletal symptoms, consistent with metabolic rather than inflammatory pathology. This case highlights the importance of recognizing LADA in patients with phenotypic discordance, autoimmune clustering, and systemic manifestations that improve with optimized glycemic control.