[Two cases of cutaneous erythema following spinal cord stimulation]

Cutaneous complications following implantation of an electric system have been reported mainly after the implantation of pacemakers, cardiac defibrillators and morphine pumps. However, cutaneous complications following implantation of spinal cord stimulators are rarely described in the literature. Here we report two cases of cutaneous eruption at the spinal cord stimulation site, one involving foreign-body reaction to silicone in the neurostimulator electrodes or connector block and the other comprising contact dermatitis to silicone.

Case 1: A 43-year-old woman had been implanted with a spinal cord stimulator. Four months after implantation, burning sensation and cutaneous inflammatory erythema were observed in the dorsolumbar region, with reduced efficiency of stimulation. Removal of the neurostimulator led to resolution of the cutaneous symptoms. Histopathological examination of the biopsy sample showed foreign-body granuloma formation. The same symptoms subsequently recurred on the surgical scar and histopathology showed granuloma formation in response to particles of silicone present in the connector. The cutaneous eruption subsided rapidly after excision. Case 2: In a 60-year-old man implanted with a spinal cord stimulator, pruriginous reticular erythema was rapidly observed on the skin just above the neurostimulator, with papules around the erythema. Histopathology of two cutaneous biopsies showed evidence of contact dermatitis. Skin-patch tests performed with components of the neurostimulator leads proved positive to two types of silicone after 72 hours. The eruption was successfully controlled using topical corticosteroid therapy.

Reports of cutaneous eruptions after spinal cord stimulation are extremely rare. Here we report two different cutaneous reactions with two different pathophysiological mechanisms, both involving silicone. The first case is original because it is the first documented case of a foreign-body reaction involving granuloma formation in response to particles of silicone present in the components of a neurostimulator. The second case concerns contact dermatitis to silicone (present in the connector block and electrode sheaths).