Euthyroid Sick Syndrome

Euthyroid Sick Syndrome is defined in the online Merck Manual. According to that definition, here is how Euthyroid Sick Syndrome and Wilson's Temperature Syndrome compare:

 
Euthyroid Sick Syndrome
Wilson's Thyroid Syndrome
Probably due to decreased T4 to T3 conversion
Yes
Yes
Thyroid Blood Tests
Always Abnormal
Typically Normal
Low Thyroid Symptoms
None
Severe
Persists after non-thyroid stress or illness has passed
No
Yes
Treated
No
Yes, reversible

Other than having one thing in common, Euthyroid Sick Syndrome and Wilson's Temperature Syndrome are almost complete opposites. Euthyroid Sick Syndrome is all about abnormal thyroid blood tests in patients without low thyroid symptoms. The condition is not considered to need treatment because there are no symptoms and the tests go back to normal when the stressful illness has passed. On the other hand, Wilson's Temperature Syndrome causes severe low thyroid symptoms and is undiagnosable with thyroid blood tests. The symptoms can persist for years after a stressful illness and can worsen with subsequent stresses. Without treatment patients may suffer indefinitely. WTS is reversible and often responds dramatically well to proper T3 therapy.