My mum had a comprehensive metabolic panel done the other day and asked me if I could help her with the test results before she talks to her doctor. I've never had a CMP done, and I'm not sure what everything means. Her carbon dioxide level was high and her anion gap was low (I don't know the exact numbers). The rest of the test came back normal. Anyone know what these two things test for and what a high or low level means?

A little background - my mum was self-diagnosed with celiac right after I was so 2.5 years ago. She's feeling much better, but not 100%. She sent away for the Enterolab casein testing the other day to see if that might be the issue.

I'm leaving town in a few hours until Monday night so if I might be a bit slow on the replies. Thanks in advance for anything you can share!

Hi,
The most common reason for a low Anion Gap is low albumin in the blood. There are many causes of this including malnutrition. which fits with Celiac.
Elevated CO2 levels are seen in ex-smokers, current smokers....usually it means that your lungs arent working at full potential. The body rids itself of excess CO2...for some reason your moms lungs are not doing this.
Do remember though that slight elevations may just be variances in lab norms. Alot of times levels vary from lab to lab by a point or two.
Best wishes, Paula

Thanks for the reply! I'm wondering if there's some mild malnutrition going on. I'm 99.9% sure she's completely gluten-free, but she still feels sick so there might be some other gut irritation that's causing slight malnutrition. I know casein can cause villi blunting, too (she just sent away for enterolab casein testing). Would something like candida cause malnutrition?

My mum's not a smoker and smoke makes her very sick so she doesn't even go places where there is smoke (so it wouldn't be a second hand smoke thing). A random thought - would something like sarcoidosis cause this? It's another autoimmune disease and her brother was recently diagnosed with it. She doesn't have any symptoms - maybe this is the beginning stage of it?

When you have lab work done there are ranges, if a test is a slight elevation it means the bloodwork is high, not a variance in a lab normal. A lot of bloodwork has specific ranges for males/females and for age groups as well. The ranges may vary from lab to lab but this is all dependent on the type of instrument and method that particiluar lab is using.

I worked in a lab as a lab tech for many years. I have cut and pasted the anion gap summary from my hospital's lab manual for you to look at. It probably does not make much sense, I know I would have a hard time understanding it and I have a background in this stuff.

The anion gap is useful in evaluation of patients with acid-base abnormalities. The sum of anions and cations must be equal in the blood.

Additional Information
Anion gap high (“unmeasured anions”): With pH high: extracellular volume contraction; massive transfusion (with renal failure and/or volume contraction); carbenicillin, penicillin (large doses), salts of organic acids such as citrate. With pH low: uremia: most common cause; abnormal anion gap in uremia is usually seen only when creatinine is >4.0 mg/dL (SI: >354 μmol/L). Uremic acidosis is rare without hyperphosphatemia. Nonketotic hyperglycemic coma and rhabdomyolysis may cause high anion gap metabolic acidosis. Lactic acidosis and diabetic or alcoholic ketoacidosis characteristically fall into this group. With normal osmolal gap: salicylate and paraldehyde toxicity; with increased osmolal gap: methanol and ethylene glycol toxicity.

High anion gap metabolic acidosis without elevated lactic acid or acetone; consider: ketoacidosis with negative or slightly positive “acetone” if the patient is hypoxic and/or has alcoholic ketoacidosis, such ketoacidosis may be life-threatening; salicylate toxicity; methanol toxicity (paint thinners); ethylene glycol toxicity (antifreeze) - urinary sediment contains abundant calcium oxalate and/or hippurate crystals; paraldehyde intoxication (may have positive ketone reactions); toluene toxicity (transmission fluid, paint thinner inhalation or sniffing).

Anion gap low: Caused by retained unmeasured anions. The most common cause is hypoalbuminemia (eg, in nephrosis, cirrhosis), dilution, hypernatremia, very marked hypercalcemia, very severe hypermagnesemia, IgG myeloma and polyclonal gamma globulin increases - hyperviscosity with certain lab instruments, lithium toxicity, bromism (low anion gap may not be present). Decreased anion gap with spurious hyperchloremia and with hyponatremia is reported in hyperlipidemia. Dilution of extracellular fluid may cause a decreased gap. The finding of a low anion gap is perceived as an unreliable diagnostic parameter and may indicate potential laboratory error.

Normal anion gap may occur with metabolic acidosis, causes have been published. They include diarrhea, renal tubular acidosis, hyperalimentation, ureteroileostomy, ureterosigmoidostomy, external drainage of pancreaticobiliary fluids, NH4Cl and other drugs.

I have also included the information for the high serum level's of Carbon Dioxide, CO2 level.
Higher-than-normal levels may be due to:

Breathing disorders
Cushing syndrome
Excessive vomiting
Hyperaldosteronism

If you have any other questions feel free to PM me and I can answer any questions you may have.

Looks like a direct quote from Wikipedia which although offers a great deal of info. can be very confusing to a person who is not in the medical profession. As well as Wikipedia is created by the general population and the info is not always accurate.
As someone who is in the medical profession, I stand by my original statement regarding labs..it is a known fact among medical professionals that "normal" lab values can vary from one lab to another and that is why many physicians will request certain labs for certain tests. Either way, again, until you have actual numbers in hand I wouldnt worry too much. The best person to speak to is your moms physician since he/she will have all of the pieces of the puzzle.
Best Wishes, Paula

Thanks, I'll pass the info on to my mum.