There are many medical causes of Diabetes. Below is a list of medical conditions that may result in elevated blood glucose and the diagnosis of Diabetes. The list, which is divided into major categories. Type 1, Type 2 and Gestational Diabetes are somewhat familiar to most people. There are other categories less known including Monogenic Diabetes or Maturity Onset Diabetes of the Young (MODY) and others. Currently, MODY accounts for less than 5% of individuals diagnosed with Diabetes. If you have MODY, characteristically three or more generations and multiple family members have Diabetes. Also, the Diabetes is diagnosed early in life and has no autoimmune basis. Some forms of MODY can be treated with diet alone, while other forms of MODY require pills or insulin therapy. With increased research into the genetic causes of Diabetes and the availability of diagnostic tests, the diagnosis of families who have a single genetic defect or MODY will increase.
The comprehesive list below is adapted from the American Diabetes Association.
Etiologic classification of Diabetes Mellitus – based on American Diabetes Association criteria
Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes—2024
1. Type 1 Diabetes (ß-cell destruction, usually leading to absolute insulin deficiency)
a. Immune-mediated
b. Idiopathic
2. Type 2 Diabetes (may range from predominantly insulin resistance with relative insulin deficiency to a predominantly secretory defect with insulin resistance)
3. Gestational Diabetes Mellitus (GDM)
4. Other specific types
a. Genetic defects of ß-cell function also known as Maturity Onset Diabetes of the Young or MODY
i. Chromosome 12, HNF-1∝ (MODY3)
ii. Chromosome 7, glucokinase (MODY2)
iii. Chromosome 20, HNF-4 (MODY1)
iv. Chromosome 13, insulin promoter factor-1 (IPF-1; MODY4)
v. Chromosome 17, HNF-1ß (MODY5)
vi. Chromosome 2, NeuroD1 (MODY6)
vii. Others
b. Genetic defects in insulin action
i. Type A insulin resistance
ii. Leprechaunism
iii. Rabson-Mendenhall syndrome
iv. Lipoatrophic Diabetes
v. Others
5. Diseases of the exocrine pancreas
a. Pancreatitis
b. Trauma/pancreatectomy
c. Neoplasia
d. Cystic Fibrosis
e. Hemochromatosis
f. Fibrocalculous pancreatopathy
g. Others
6. Endocrinopathies
a. Acromegaly
b. Cushing's syndrome
c. Glucagonoma
d. Pheochromocytoma
e. Hyperthyroidism
f. Somatostatinoma
g. Aldosteronoma
h. Others
7. Drug- or chemical-induced
a. Glucocorticoids
b. Check point inhibitors
c. Tacrolimus and Sirolimus
d. Pentamidine
e. Nicotinic acid
f. Thyroid hormone
g. Diazoxide
h. ß-adrenergic agonists
i. Thiazides
j. Dilantin
k. ∝-Interferon
l. Vacor
8. Others
a. Infections
i. Congenital rubella
ii. Cytomegalovirus
iii. Others
b. Uncommon forms of immune-mediated diabetes
i. "Stiff-man" syndrome
ii. Anti–insulin receptor antibodies
iii. Others
9. Other genetic syndromes sometimes associated with diabetes
a. Down's syndrome
b. Klinefelter's syndrome
c. Turner's syndrome
d. Wolfram's syndrome and other Mitochondrial DNA disorders
e. Friedreich's ataxia
f. Huntington's chorea
g. Laurence-Moon-Biedl syndrome
h. Myotonic dystrophy
i. Porphyria
j. Prader-Willi syndrome
k. Others
Patients with any form of Diabetes may require insulin treatment at some stage of their disease. The use of insulin does not, itself, classify Diabetes.