Distinguish between diabetes mellitus and diabetes insipidus (endocrine gland concerned).
Topic: Diabetes mellitus and diabetes insipidus
Answer
DIABETES MELLITUS: caused by a deficiency of INSULIN from the PANCREAS (the islets of Langerhans).
DIABETES INSIPIDUS: caused by a deficiency of ANTIDIURETIC HORMONE from the POSTERIOR LOBE OF THE PITUITARY GLAND.
The question states the basis in brackets — ENDOCRINE GLAND CONCERNED — so the gland must be named for each. Naming only the hormones would not answer it.
THE TWO DISORDERS SHARE A NAME AND NOTHING ELSE. Both produce excessive urination, which is why both are called "diabetes" (meaning to siphon), but the cause and the treatment are completely different.
The second words tell them apart, and both are worth knowing: MELLITUS means honey-sweet — the urine contains sugar INSIPIDUS means tasteless — the urine contains no sugar Physicians once diagnosed them exactly that way.
| Point of difference | Diabetes mellitus | Diabetes insipidus |
|---|---|---|
| Gland concerned | Pancreas (islets of Langerhans) | Pituitary (posterior lobe) |
| Hormone lacking | Insulin | Antidiuretic hormone (vasopressin) |
| Sugar in urine | Present | Absent |
| Urine | Large volume, containing glucose | Very large volume, dilute, no glucose |