The phrase "unknown etiology" refers to a situation where the cause or origin of a particular condition or disease is not known or understood. It means that experts are unsure about what has caused the problem. Full definition
(30 - 31) Sarcoidosis A unusual lung disease of unknown etiology called Sarcoidosis is linked to gluten sensitivity. (bioidenticalhormones101.com)
Estriol and Progesterone are showing to be very promising in the treatment of MS.Multiple sclerosis (MS) is an autoimmune disease of unknown etiology characterized by the inflammatory demyelination of the central nervous system and breakdown of the blood - brain barrier. (holtorfmed.com)
Any person practicing veterinary medicine in this state shall immediately notify ODA by telephone upon observing any unidentified vesicular disease, any exotic disease or foreign animal disease, even if only suspected or any disease of unknown etiology exhibiting highly pathogenic or lethal effect. (oregonvma.org)