Type 1 diabetes

Last reviewed: 6 Sep 2022
Last updated: 28 Jul 2021

Summary

Definition

History and exam

Key diagnostic factors

  • hyperglycaemia
  • polyuria
  • polydipsia
More key diagnostic factors

Other diagnostic factors

  • young age
  • weight loss
  • blurred vision
  • nausea and vomiting
  • abdominal pain
  • clinical dehydration
  • abdominal pain
  • tachypnoea
  • lethargy
  • coma or altered mental status
Other diagnostic factors

Risk factors

  • genetic predisposition
  • geographical region
  • infectious agents
  • dietary factors
More risk factors

Diagnostic investigations

1st investigations to order

  • random plasma glucose (children)
  • fasting plasma glucose (children)
  • 2-hour plasma glucose (children)
  • HbA1c (children)
  • clinical diagnosis (adults)
More 1st investigations to order

Investigations to consider

  • plasma or urine ketones
  • C-peptide
  • autoimmune markers
More investigations to consider

Treatment algorithm

ONGOING

children and non-pregnant adults

pregnant

Contributors

Authors

Eveleigh Nicholson, MBBS, FRCP

Consultant Endocrinologist

Portsmouth Hospitals University NHS Trust

UK

Disclosures

EN has received honoraria for educational activities/advisory boards from NovoNordisk, Eli Lilly and Boehringer Ingelheim.

Sze May Ng, MBBS (Hons), FHEA, FRCPCH, SFFMLM, MSc, LLM, MBA, PhD

Honorary Associate Professor

University of Liverpool

Consultant Paediatrician and Paediatric Endocrinologist

Southport and Ormskirk NHS Trust

UK

Disclosures

SMN declares that she has no competing interests.

Partha Kar, OBE, MBBS MD, FRCP

Consultant Endocrinologist

Portsmouth Hospitals University NHS Trust

National Specialty Advisor, Diabetes, NHS England

UK

Disclosures

PK has sat on advisory boards and attended events reimbursed by Novo Nordisk, Eli Lilly and Sanofi.

Acknowledgements

Dr Eveleigh Nicholson, Dr Sze May Ng, and Professor Partha Kar would like to gratefully acknowledge Dr Rajesh K. Garg and Dr Varsha Vimalananda, the previous contributors to this topic.

Disclosures

RKG is an author of a number of references cited in this topic. VV declares that she has no competing interests.

Peer reviewers

Omar Mustafa, MBChB, FRCP

Consultant Physician in Diabetes

Senior Lecturer in Medical Education

King's College Hospital NHS Foundation Trust

King’s College London

London

UK

Disclosures

OM has received honoraria for educational activities/lectures from NovoNordisk, Eli Lilly, Sanofi, and Boehringer Ingelheim.

Hood Thabit, MB, BCh, MD, PhD

Consultant Diabetologist & Honorary Senior Lecturer

Manchester University Hospitals NHS Foundation Trust

University of Manchester

Manchester

UK

Disclosures

HT has received research support from Dexcom, Inc., and speaker fees from Eli Lilly.

  • Differentials

    • Monogenic diabetes: maturity onset diabetes of the young
    • Neonatal diabetes
    • Latent autoimmune diabetes in adults (LADA)
    More Differentials
  • Guidelines

    • Type 1 diabetes in adults: diagnosis and management
    • Diabetes (type 1 and type 2) in children and young people: diagnosis and management
    More Guidelines
  • Patient leaflets

    Diabetes type 1: what is it?

    Diabetes type 1: what treatments work?

    More Patient leaflets
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