I also heard this when I used to get DKA with a seasonal bug each year back in the '80s and '90s. The increased urination drains out sodium. The low sodium can persist for a little while even after IV saline, if the saline intake didn’t sufficiently compensate for the amount of sodium lost with increased urination resulting from the IV infusion.
@CatLady, good to hear all’s well once again and you’re safely back home!
Thanks for all the support and food-for-thought: I follow up with my HCP next week and have a lot to discuss. 
Just some follow-up:
Still having some GI symptoms 
and challenges managing my BG though staying in a more normal range. Boluses only starting to work normally, appetite so-so. Blood tests indicated I did have an infection but fecal tests so far have drawn a blank. I feel tired and down and not very confident in my D devices and management skills. Thanks for listening.
Very sorry to hear all of that. Please keep us updated. Thinking of you.
As always, sending you warm vibes and hoping for a speedy recovery.
Hope your appointment next week goes well. Best wishes.
Sending you good thoughts and hugs. Hope you feel better 
I’m so sorry, @CatLady. I sure hope you get some answers and good news soon! I’m sending you a big hug!
Thinking about you, @CatLady! Hoping for the best for you! 
CatLady,
How have you been feeling lately? Have your blood glucose numbers been more stable? Infections under control? Hopefully, no more trips to the ER.
Thanks for asking.
I am doing much better with all things GI finally back to normal in the last few days. I am taking a daily probiotic and eating some low-sugar yogurt to help things along. I am also working with a new CDE to put together a sick day plan for severe illness (I was so ill-prepared, no pun intended) and to help with some other D stuff. I told her about our forum and she cracked up about the name!! 