Difference between "acute", "chronic" and "obtuse" in the sense of illness

Solution 1:

A chronic condition is one that persists for a long time. Asthma is a chronic condition: if you have asthma today, then you almost certainly had asthma yesterday and will still have it next week. Source and more details: Medline, OED.

Acute has two relevant meanings. In colloquial usage, it just means severe; so in that sense, a condition can be both acute and chronic. However, in medical language, it is specifically used in contrast to chronic; an acute condition, in this sense, is something which by its nature is (expected to be) of limited duration; something which develops over a short timescale. So in this technical sense, a condition cannot be both acute and chronic. An asthma attack is acute in this sense: it’s a temporary flare-up of the underlying chronic condition. Source and more details: Medline, OED.

Obtuse is essentially irrelevant to these medical usages; it was used in a comparable sense in the past, but this usage is now extremely rare (OED; Google ngrams). In mathematics, however, it is still used in contrast to acute. An acute angle is one measuring less than 90°, while an angle more than 90° (but less than 180°) is obtuse.

Solution 2:

From:

http://www.nlm.nih.gov/medlineplus/ency/imagepages/18126.htm

Acute conditions are severe and sudden in onset. This could describe anything from a broken bone to an asthma attack. A chronic condition, by contrast is a long-developing syndrome, such as osteoporosis or asthma. Note that osteoporosis, a chronic condition, may cause a broken bone, an acute condition. An acute asthma attack occurs in the midst of the chronic disease of asthma. Acute conditions, such as a first asthma attack, may lead to a chronic syndrome if untreated.

Obtuse is a geometry term. Being called obtuse is generally considered an insult.

Solution 3:

The link, you cited, mentions that in case of illnesses, acute and chronic are antonyms.

The adjective Obtuse, which means slow or unwilling to understand something, is not used with illnesses.

P.S.- Acute angle and Obtuse angle are nouns, which are used in geometry.

Solution 4:

A chronic disease can have an acute onset or acute symptoms, but the disease itself would not be considered acute.

There is no such thing as an "obtuse illness"