Hi everyone, I recently had sweat tests as I am on Kalydeco, and I was curious to find out about normal chloride values. I found that there is limited research looking at sweat chloride in non CFs over different age groups. However, one of the best quality studies found the following results:
Median sweat chloride values (95% RI):
Age 5-9: 12.6 (1-39 mmol/L)
Age 10-14: 17.2 (3-47 mmol/L)
Age 15-19: 19.4 (3-51mmol/L)
Age 20+: 22.7 (5-56mmol/L)
Source: http://www.ncbi.nlm.nih.gov/pubmed/18589442. This study did not include people with respiratory symptoms or F508del.
Past the age of 20 there was no significant change. I know some people here had asked about this in other topics, and this confirms what some people here thought, that the sweat chloride normally increases during childhood.
The 95% RIs are similar to the values that were found in each of the groups (the article has a dot plot showing this). The 95% Reference Interval is the predicted range of 95% of the non CF population (5% higher or lower than the range).
Some adults on Kalydeco have had sweat chloride scores as low as 27, which is normal (the 75% interval was about 30 in the 20-30 age group, so 75% of the people were below 30). Mine changed from 102 to 54, so I'm much closer to the median/normal (I am technically within the normal 95% RI but I dont call this normal). I have also read that two children under the age of 9 now have sweat tests in the 14-17 range, which is normal (75% interval was about 19 at age 5-9).
Median sweat chloride values (95% RI):
Age 5-9: 12.6 (1-39 mmol/L)
Age 10-14: 17.2 (3-47 mmol/L)
Age 15-19: 19.4 (3-51mmol/L)
Age 20+: 22.7 (5-56mmol/L)
Source: http://www.ncbi.nlm.nih.gov/pubmed/18589442. This study did not include people with respiratory symptoms or F508del.
Past the age of 20 there was no significant change. I know some people here had asked about this in other topics, and this confirms what some people here thought, that the sweat chloride normally increases during childhood.
The 95% RIs are similar to the values that were found in each of the groups (the article has a dot plot showing this). The 95% Reference Interval is the predicted range of 95% of the non CF population (5% higher or lower than the range).
Some adults on Kalydeco have had sweat chloride scores as low as 27, which is normal (the 75% interval was about 30 in the 20-30 age group, so 75% of the people were below 30). Mine changed from 102 to 54, so I'm much closer to the median/normal (I am technically within the normal 95% RI but I dont call this normal). I have also read that two children under the age of 9 now have sweat tests in the 14-17 range, which is normal (75% interval was about 19 at age 5-9).