Summary
Definition
History and exam
Key diagnostic factors
- history of diabetes mellitus
- severe intercurrent illness or infection (hyperglycemia)
- insulin use (hypoglycemia)
- reduced level of consciousness/coma (hypoglycemia and hyperglycemia)
- sweating (hypoglycemia)
- tachycardia (hypoglycemia)
- unusual behavior (hypoglycemia)
Other diagnostic factors
- history of recent corticosteroid use
- signs of diabetic retinopathy
- signs of diabetic neuropathy
- polyuria, polydipsia, or unintentional weight loss
Risk factors
- severe illness (hyperglycemia or hypoglycemia)
- corticosteroid use (hyperglycemia)
- poorly controlled diabetes mellitus (hyperglycemia)
- insulin administration or insulin secretagogues (hypoglycemia)
- changes to corticosteroid or insulin regimen (hypoglycemia or hyperglycemia)
- poor nutritional intake (hypoglycemia)
- older age or cognitive impairment (hypoglycemia)
Diagnostic tests
1st tests to order
- random plasma glucose
- HbA1c
- serum BUN, creatinine, and eGFR
- spot urine albumin/creatinine ratio
- serum ketones
Tests to consider
- post-discharge fasting plasma glucose or HbA1c
- post-discharge 2-hour postload glucose after 75 g oral glucose
Treatment algorithm
critically ill or unplanned surgery or in ICU: hyperglycemia
stable noncritical illness: uncontrolled hyperglycemia
stable noncritical illness: well-controlled known diabetes
hypoglycemia
preoperative: minor elective surgery
Contributors
Authors
M. Cecilia Lansang, MD, MPH
Professor of Medicine
Director of Endocrinology, Main Campus
Department of Endocrinology, Diabetes and Metabolism
Cleveland Clinic
Cleveland
OH
Disclosures
MCL has received research support from Dexcom, Xeris, and Abbott. She is also a consultant at Glooko.
Keren Zhou, MD
Clinical Assistant Professor of Medicine
Research Director, Endocrinology and Metabolism Institute
Department of Endocrinology, Diabetes and Metabolism
Cleveland Clinic
Cleveland
OH
Disclosures
KZ declares that she has no competing interests
Acknowledgements
Dr M. Cecilia Lansang and Dr Keren Zhou would like to gratefully acknowledge Dr Suzanne Quinn, Dr Ajay Rao, and Dr Vivian Fonseca, previous contributors to this topic.
Disclosures
SQ, AR, and VF declare that they have no competing interests.
Peer reviewers
Guillermo E. Umpierrez, MD
Professor of Medicine
Division of Endocrinology
Metabolism and Lipids
Emory University School of Medicine
Atlanta
GA
Disclosures
GEU is an author of a number of references cited in this monograph.
Daniel Morganstein, MBBS, MA (Cantab), MRCP, PhD
Consultant Diabetologist
Beta Cell Unit
Chelsea and Westminster NHS Trust
London
UK
Disclosures
DM declares that he has no competing interests.
Sean Dinneen, MBBCh, FRCPI, FACP
Senior Lecturer in Medicine
National University of Ireland
Consultant in Diabetes and Endocrinology
Galway University Hospitals
Galway
Ireland
Disclosures
SD declares that he has no competing interests.
Differentials
- Transient hyperglycemia (e.g., from stress, corticosteroids, parenteral/enteral nutrition)
- Type 1 diabetes mellitus
- Type 2 diabetes mellitus
More DifferentialsGuidelines
- Standards of care in diabetes - 2024
- Management of individuals with diabetes at high risk for hypoglycemia: clinical practice guideline
More GuidelinesPatient information
Diabetes: what is it?
Diabetes type 2: should I take insulin?
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