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Type 1 diabetes mellitus

Last reviewed: 11 Nov 2024
Last updated: 07 Jun 2024

Summary

Definition

History and exam

Key diagnostic factors

  • polyuria
  • polydipsia
  • diabetic ketoacidosis
Full details

Other diagnostic factors

  • young age
  • weight loss
  • blurred vision
  • nausea and vomiting
  • abdominal pain
  • tachypnea
  • lethargy
  • altered mental status
Full details

Risk factors

  • genetic predisposition
  • geographic region
  • infectious agents
  • dietary factors
  • drug-induced
Full details

Diagnostic tests

1st tests to order

  • HbA1c
  • fasting plasma glucose
  • 2-hour post-glucose load plasma glucose
  • random plasma glucose
Full details

Tests to consider

  • plasma or urine ketones
  • fasting C-peptide
  • autoimmune markers
Full details

Treatment algorithm

ONGOING

nonpregnant

pregnant

Contributors

Authors

Rajesh K. Garg, MD
Rajesh K. Garg

Professor of Medicine

David Geffen School of Medicine at UCLA

Harbor-UCLA Medical Center

Torrance

CA

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.

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