** Shares of medical device maker Dexcom DXCM.O slipped 2.3% to $70.43, snapping a six-day gaining streak

** The firm says some of its glucose sensors meant for disposal were stolen and sold by third parties

** Dexcom warns patients not to use sensors from the affected batches and to seek replacements

** Some of the stolen sensors may cause skin infections or fail to give readings - Dexcom

** Adds that it is working with regulators to investigate and says no serious harm is reported

** The issue involves Dexcom's G7 continuous glucose monitoring sensors

** As of last close, stock up 8.6% YTD