[DanaH]

Corrected calcium levels to determine hypercalcemia

by DanaH on Sun Jul 13, 2014 4:09 pm

Hello all,

I remember reading either a Beacon forum post or a news article which discussed corrected calcium levels to determine the "C" in CRAB, hypercalcemia, but can't seem to locate it.

I realize there is a formula to use to determine this corrected value, but am somewhat confused about it. Is it used when we have an abnormally high or abnormally low albumin level in a set of labs which also reflects an elevated calcium level?

From what I have found, the albumin threshold is 4.0, but I am not sure if we apply it to values below or above this value to correct the calcium.

Thanks to all who can share and provide insight so I can get a better handle on this.

All the best,
Dana H.

[dnalex]

Re: Corrected calcium levels to determine hypercalcemia

by dnalex on Sun Jul 13, 2014 4:56 pm

This is the formula

Serum calcium + 0.8 x (4 - serum albumin)

From this site
http://www.globalrph.com/calcium.htm

[Multibilly]

Re: Corrected calcium levels to determine hypercalcemia

by Multibilly on Sun Jul 13, 2014 4:57 pm

Hey Dana,

I remember going through this analysis when I had accidentally caused my own temporary hypercalcemia due to too much vitamin D consumption. This spells out when one uses it:

http://emedicine.medscape.com/article/240681-overview

For every 1-g/dL drop in serum albumin below 4 g/dL, measured serum calcium decreases by 0.8 mg/dL. Therefore, to correct for an albumin level of less than 4 g/dL, one should add 0.8 to the measured value of calcium for each 1-g/dL decrease in albumin. Without this correction, an abnormally high serum calcium level may appear to be normal.

[DanaH]

Re: Corrected calcium levels to determine hypercalcemia

by DanaH on Sun Jul 13, 2014 5:11 pm

Thanks so much Alex, much appreciated!

Now I just need to find out if corrected calcium is actually the right way to determine hypercalciumia for the C in CRAB. I am pretty certain I read this in the Beacon, so I will keep searching within this site.

All the best
Dana H

[DanaH]

Re: Corrected calcium levels to determine hypercalcemia

by DanaH on Sun Jul 13, 2014 5:18 pm

Hey Multibilly,

Thanks so much. So I have an albumin level greater than 4.0 and and an elevated calcium level this set of labs. Can I still use this formula to correct? I used the link Alex provided with the calculator and it did correct my CA to a lower reading. I am just confused.

Thanks if you can give this some thought and help me out.

Best to you.
Dana H

[dnalex]

Re: Corrected calcium levels to determine hypercalcemia

by dnalex on Sun Jul 13, 2014 5:24 pm

Hi Dana,

If your albumin levels are higher than 4, then you do not calculate corrected calcium. The formula is used only when the albumin levels are below 4.

[DanaH]

Re: Corrected calcium levels to determine hypercalcemia

by DanaH on Sun Jul 13, 2014 5:28 pm

Got it Alex, many thanks. Someone suggested an ionized calcium test as well, any idea if this has any utility in multiple myeloma? Will also be exploring parathyroid as a possible differential.

[Multibilly]

Re: Corrected calcium levels to determine hypercalcemia

by Multibilly on Sun Jul 13, 2014 5:38 pm

I think Dnalex is right.

Just a thought, but you may want to look at your vitamin D consumption if you just went hyper. My calcium level has been perfect ever since I dropped my D3 intake down.

Vitamin D3 and multiple myeloma

It's important to keep up one ones' vitamin D intake, but you can also easily overdo it. Some supplements and multivitamins are just way overloaded with it.

I now also take D3 with Vitamin K2, which allegedly really helps with the vitamin D absorption. I already get a lot of calcium in my diet, so I don't worry about that at all ... especially since my dexa scans show that I have really dense bones.

[DanaH]

Re: Corrected calcium levels to determine hypercalcemia

by DanaH on Sun Jul 13, 2014 5:55 pm

Multibilly,

Very helpful earlier discussion via your link .. .and I will get the D level checked as well. I have been using a D3 supplement and in the summer sun. Perhaps the supplement is more than I need for now.

Thanks for the info / thoughts. Always appreciated.

Dana

[Boris Simkovich]

Re: Corrected calcium levels to determine hypercalcemia

by Boris Simkovich on Sun Jul 13, 2014 8:54 pm

Thanks, everyone, for helping Dana with her question. This has been a very useful discussion.

Dana, I think this is the discussion thread that you've been searching for:

Maximum values for smoldering myeloma?

There is the posting in the discussion that lists the diagnostic criteria for multiple myeloma, smoldering myeloma, and MGUS straight out of the Wikipedia article about multiple myeloma that was current at the time.

You mentioned in the above discussion that you were surprised that the calcium level referred to in the diagnostic criteria is the corrected calcium level. So I'm fairly certain this is the discussion that you've had in mind.

Great to hear that you've been getting a lot of sun this summer! Take care.