Type 1 diabetes mellitus
Summary
Definition
History and exam
Key diagnostic factors
- polyuria
- polydipsia
- diabetic ketoacidosis
Other diagnostic factors
- young age
- weight loss
- blurred vision
- nausea and vomiting
- abdominal pain
- tachypnea
- lethargy
- altered mental status
Risk factors
- genetic predisposition
- geographic region
- infectious agents
- dietary factors
- drug-induced
Diagnostic investigations
1st investigations to order
- random plasma glucose
- fasting plasma glucose
- 2-hour plasma glucose
- HbA1c
Investigations to consider
- plasma or urine ketones
- fasting C-peptide
- autoimmune markers
Treatment algorithm
nonpregnant
pregnant
Contributors
Authors
Rajesh K. Garg, MD
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
- Monogenic diabetes: maturity onset diabetes of the young
- Monogenic diabetes: neonatal diabetes
- Latent autoimmune diabetes in adults (LADA)
More DifferentialsGuidelines
- Standards of medical care in diabetes - 2022
- Clinical practice guidelines for the prevention and management of diabetes in Canada
More GuidelinesPatient leaflets
Diabetes type 1: what is it?
Diabetes type 1: what treatments work?
More Patient leaflets
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