I knew I would be getting a request to have my A1C bloodwork done in September, and so I did indeed receive a (probably) automated message that it was time, and the message had a handy link for making an appointment with the laboratory. But first I wanted to make a request to Dr. Prabaharan.
From: Jacqueline Hegarty V
Sent: 10/11/2021 3:41 PM PDT
To: VELUMMYLUM PRABAHARAN MD
Subject: Lab tests
I received a message that it’s time to have my A1C test done. I would like to request a c-peptide test as well. Also, is it possible to get a fasting insulin test?
I will await your response.
Thank you for your help.
VELUMMYLUM PRABAHARAN MD
Received:10/11/2021
To Jacqueline Hegarty V (Viewed)
Message body:
Thank you for your message. I will be out of the office through 10/24/2021 and will follow up with you after I return.
Oh, great! That’s almost two weeks away. Well, I figured someone in his office would respond to me. Which they did.
CHI-NA PAK MD
Received:10/12/2021
Hi Ms. Hegarty,
Thank you for your message. My name is Dr. Chi-Na Pak and I work on the same care team as VELUMMYLUM PRABAHARAN MD. I’m responding on their behalf so we can address your questions or concerns as quickly as possible.
Could you please clarify your question or concern and requesting the C-peptide testing fasting insulin? You have had diabetes for decades and these tests would not be diagnostically indicated. It also would not make sense if you are currently taking insulin. Please clarify what your question or concern was so we can best advise.
Please don’t hesitate to reach out again if needed.
Warmly,
Dr. Chi-Na Pak
I did not hesitate to “reach out again.”
From: Jacqueline Hegarty V
Sent: 10/12/2021 12:42 PM PDT
Subject: Re: C-peptide lab test
Dear Dr. Pak,
My reasons for wanting a c-peptide test are these:
1) I want to avoid hyperinsulinemia.
2) But I also want to know if my endogenous insulin production is low enough to indicate type 1 (or type 1.5 LADA) diabetes.
Dr. Prabaharan has ordered the c-peptide test in the past for these reasons.
Here is the link to an article I found:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5446389/
Among other things, it says:
‘C-peptide is a useful and widely used method of assessing pancreatic beta cell function.’
‘Half of all insulin secreted by the pancreas is metabolized in the liver by first-pass metabolism, whereas c-peptide has negligible hepatic clearance. C-peptide is cleared in the peripheral circulation at a constant rate, whereas insulin is cleared variably making direct measurement less consistent. In insulin-treated patients with diabetes, measurement of c-peptide also avoids the pitfall of cross-reaction of assay between exogenous and endogenous insulin.’
Jacqueline Hegarty
Dr. Pak did not respond, but someone else did.
S G THAMARASSERIL MD
Received:10/13/2021
To Jacqueline Hegarty V (Viewed)
Message body:
Dear Ms. Hegarty,
(I am covering for VELUMMYLUM PRABAHARAN MD who is away from the office today.)
I reviewed your chart and I see that you are diagnosed with Type 2 Diabetes and is on insulin. Your body is benefiting from external insulin administration to control your sugars already. There is no clinical utility in checking C peptide which represents endogenous insulin production.
You had C peptide checked early this year.
C Peptide is not routinely measured and there is no utility in regularly checking it in your case.
Autoimmune mediated diabetes is diagnosed by checking antibodies.
If you are having low blood sugars recommend titrating down the insulin dose. Fasting sugar is less than 150 and 2 hours after meals is less than 200.
Please follow up with VELUMMYLUM PRABAHARAN MD when he returns if you have any additional questions regarding this.
Regards,
S G THAMARASSERIL MD
(She did not allow a reply to her message, so I sent my reply to Dr. Pak.)
From: Jacqueline Hegarty V
Sent: 10/13/2021 3:26 PM PDT
Subject: Re: Lab tests
Dear Dr. Pak,
I see that Dr S G THAMARASSERIL is not going to order a c-peptide test (much less fasting insulin!), so I will just wait until Dr. Prabaharan is back in the office after 10/24/21.
I aim for a fasting BG in the range of 70-99 mg/dL with 1-hr spikes no greater than 140 mg/dL.
It’s important to me to know if my body is still making endogenous insulin, which a c-peptide test could tell me.
But thank you for your time.
Jacqueline Hegarty
Neither of the responding doctors apparently have English as a first language. But, more importantly, neither of them GOT what I was trying to say! I’m particularly blown away by Dr. Thamarasseril’s implication that a fasting blood sugar is “okay” at 150 (mg/dL) and post-prandial at <200!
I plan to do nothing more at this time. No more messages to Dr. Prabaharan, and I’ll wait to see if he answers my original message when he gets back after 10/24/2021. I’ll post again then.
If it turns out that Dr. Prabaharan will no longer order the c-peptide (and I’m not even going to ask again about fasting insulin!), then I will have to think about the possibility of getting those tests at a third-party lab. Haven’t figured out yet the best way to do that.