Gout is usually a problem when uric acid is over 5mg/dL, so can we get gout at 3.5?
Gout is caused by excess uric acid. The medical term for this is hyperuricemia. As I explain in those guidelines, doctors usually regard 7 as the start of hyperuricemia. I believe 7 is too high, as I believe anything over 5 carries the risk of gout, but is 5 still too high?
A friend asked me about gout at 3.5:
I have a friend who is having severe gouty attacks… But he claims his uric acid is 3.5. I am dumbfounded. Has anyone heard of this sort of thing??
Here is an extended version of my reply.
Three Reasons for Low Uric Acid Gout
Differential Gout Diagnosis
1. It isn’t gout.
I know that septic arthritis and pseudogout (calcium crystals not uric acid crystals) have similar symptoms. There may be others. A rheumatologist could differentiate this with joint fluid analysis.
In Gout & Rheumatoid Arthritis, I listed several common diseases that might be confused with gout. As well as septic arthritis and pseudogout, that gout study identifies traumatic arthritis and rheumatoid arthritis as diseases that might be confused with gout. If you know of others, please let me know in the Gout at 3.5 discussion.
Uric Acid Conversion
2. It isn’t 3.5.
With an international view, I see mg/dL, mmol/L and μmol/L regularly. Your friend won’t be the first person to confuse 0.35mmol/L with 3.5mg/dL. 0.35mmol/L is still fairly low, but not unreasonable as blood uric acid usually falls during a gouty attack.
For everything you need to know about different scales for measuring uric acid, please see:
- Uric Acid Concentration Conversion if you like the precision of a calculator
- Uric Acid Levels Chart if you want the big picture of the scale of uric acid levels.
Low Temperature Gout
3. It is low temperature gout.
Someone exposed to prolonged low temperature can get gout with uric acid below the normally safe level of 5mg/dL.
The crystallization point for uric acid at normal body temperature is 6.8mg/dL. Other factors affect urate crystallization, and temperature tends to be lower in the joints, especially at the extremities. This explains why toes and fingers are commonly the first joints to show gout symptoms. It also explains why 5mg/dL is the recommended maximum for safe uric acid levels.
But gout management must be done on a personal case-by-case basis. 5mg/dL is safe for most people, but there are exceptions. In Do You Work For Gout?, I reported the case of a fisherman exposed to low temperatures who suffered gouty tophi in his hands. I explain more about the affects of low temperature on gout in Gout Without Hyperuricemia.
All of this emphasizes the need to treat gout on a case-by-case basis. It is useful to have general guidelines, such as: 5 is the safe maximum for uric acid. However, that should not blind us to other possibilities. If gout is suspected, but the diagnosis is not apparent, then patients should always be referred to a rheumatologist for joint fluid analysis.
It also shows us the power of discussing individual gout cases. I have a very important post about gout forums in the pipeline. Never underestimate the power of discussing your gout.