**4.3 Retrospective single centre study on the safety and microbial hazards of prolonged transcutaneous sensor insertion (2004–2007)**

Inflammation is a potential adverse event at the site of sensor insertion. In eight studies, there were 364 transcutaneous sensors used in 169 men and women with diabetes and in 40 healthy persons. The skin was sprayed with an antiseptic before sensor insertion. In the course of 2117 sensor days, there was only one serious complication: an abscess in the gluteal region. We demonstrate this case report [120].

History: A man born in 1972 with T1D from 1981, on insulin pump since 2002, from 2003 he used 15 sensors without any complication except occasional slight redness and increased sensitivity at the site of insertion. On 14.3.07, the patient inserted a sensor in the middle of the right gluteal area 14 cm below spina illiaca posterior superior. Before insertion, the site was sprayed by antiseptic. The third day

## **Figure 29.**

*Healing serious adverse events after sensor insertion. Scar after the abscess drain (left lower corner). New sensor and transmitter (right upper corner).*

after insertion pain and aedema appeared, the fourth day the sensor was removed, the pain became more severe so 5 days later (23.3.07) he contacted the diabetes centre.

On examination: Redness and infiltration 5 cm of diameter. Small incision in local anaesthesia (Mesocain 1%) was performed, 10–20 ml of purulent fluid was evacuated. The wound rinsed using physiological solution and drained. New sensor was inserted (**Figure 29**).

Microbial culture: Streptococcus pyogenes. No antibiotics were given. Within 14 days after surgical intervention, the local redness and pain disappeared and no signs of secretion or retention were seen. A small scar remains.

**Conclusions:** In the course of the FDA-approved period for sensor insertion only one serious adverse event occurred. There were no other serious adverse events in sensors used for up to 9 days. Hence, from the point of view of potential microbial hazards prolonged insertion of sensors appears to be safe. These conclusions are supported by other studies [72].
