Type 1 diabetes mellitus

Last reviewed: 1 Nov 2022
Last updated: 06 May 2022

Summary

Definition

History and exam

Key diagnostic factors

  • polyuria
  • polydipsia
  • diabetic ketoacidosis
More key diagnostic factors

Other diagnostic factors

  • young age
  • weight loss
  • blurred vision
  • nausea and vomiting
  • abdominal pain
  • tachypnea
  • lethargy
  • altered mental status
Other diagnostic factors

Risk factors

  • genetic predisposition
  • geographic region
  • infectious agents
  • dietary factors
  • drug-induced
More risk factors

Diagnostic investigations

1st investigations to order

  • random plasma glucose
  • fasting plasma glucose
  • 2-hour plasma glucose
  • HbA1c
More 1st investigations to order

Investigations to consider

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

Treatment algorithm

ONGOING

nonpregnant

pregnant

Contributors

Authors

Rajesh K. Garg, MD
Rajesh K. Garg

Professor of Medicine

University of Miami, Miller School of Medicine

Miami

FL

Disclosures

RKG is an author of a number of references cited in this topic.

Acknowledgements

Dr Rajesh K. Garg would like to gratefully acknowledge Dr Varsha Vimalananda, previous contributor to this topic.

Disclosures

VV declares that she has no competing interests.

Peer reviewers

Zachary Bloomgarden, MD

Clinical Professor

Medicine/Endocrinology

Diabetes and Bone Disease

Mount Sinai School of Medicine

New York

NY

Disclosures

ZB declares that he has no competing interests.

Alicia Jenkins, MB, BS, MD, FRACP, FRCP

Associate Professor

Department of Medicine

University of Melbourne

Melbourne

Australia

Professor

Harold Hamm Oklahoma Diabetes Center

University of Oklahoma Health Sciences Center

Oklahoma City

OK

Disclosures

AJ has been a (non-salaried) co-investigator on multi-center clinical trials supported by Novo, Eli Lilly, Sanofi-Aventis, and Medtronic. She does not hold any stocks or shares in these companies. She has received a speaker's honorarium from Novo Nordisk.

  • Differentials

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  • Guidelines

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  • Patient leaflets

    Diabetes type 1: what is it?

    Diabetes type 1: what treatments work?

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