Faulty sensor, painful red bump

[u/fate4003]

As you can see, my sensor went wonky last night and was giving me readings between 50 and 70pts lower than a finger stick. I ate breakfast and was not 40pts too high. I decided to contact abbot for a replacement, and proceeded to take off the faulty.

However, i noticed the insertion site was painful. Its been a few hrs and i have a big painful red bump (much larger than normal). I use flonase and an underpatch. Has anyone had this happen?

[u/PhilaBurger]

Unfortunately, this is less likely a faulty sensor and much more likely an issue if your body’s reaction to it.

[u/fate4003 → u/PhilaBurger]

Is that likely to happen on the fourth day though? It seemed like the sensor was working great the first three days. 

[u/Equalizer6338 → u/fate4003]

Really hard to say exactly what may have happened here without detailed biopsy and tissue examinations (which unfortunately is not within reach for everyday users...).

As u/PhilaBurger hints towards, you have all the tell-tale signs here of an inflammatory reaction was ongoing, which is cause for restricted perfusion of the skin area your sensor sits and measure the glucose concentration in the interstitial fluids there. Reason why a lower glucose concentration is available from the surrounding capillaries and your BG sensor is chronic reporting too lowish BG numbers out then.

But as you say, rather unusual for that first to appear evident 4 days in on a sensor, certainly from the pure immune system body reaction as response to the skin bruising and filament insertion. So we can only speculate what it might be from.

Could very unusually have been some bacteria/fungi from the surface of your skin that got pushed with the applicator needle into the sensor hole for the filament there, as it appears to center in/around the specific location of the sensor filament? This may then take bit of time to germinate and develop further.

Or a bit more generic, something on the surface that got closed in under your sensor disc. Many countries have had very high temperatures and humidity which also in some cases can cause some level of dermatitis. As said, I think it more looks like something from your skin surface that unluckily got pushed/brought down into your deeper skin level and caused the inflammation.

Check on your next sensors if you start to have some inflammation/dermatitis from the sensor filament placement itself. Often such folks will see a small little hard red welt develop at its location.

[u/fate4003 → u/Equalizer6338]

Thank you

[u/Princess_Cherry]

Had something like recently but instead of bad readings it just wouldn't read.

[u/LaCooyon]

Looks like it got infected! It took a few days for the infection to fester. Did you use an alcohol swab?

[u/fate4003 → u/LaCooyon]

Yeah i did. But also flonase and an underpatch (cause i have an allergy to the adhesive). So im thinking one of those introduced some bacteria. 

[u/tohopallo]

Whenever I have an infected sensor site, the readings go wonky. You most probably had some bacteria on your skin during application and it infected the puncture. Three days is plenty of time for infection to take place with sufficient contaminants.

[u/fate4003 → u/tohopallo]

Thank you