A 51 yo male was working on his car in the rain and was found unconscious with the rash below.

What happened?

This patient presents with Lichtenberg figures from a lightning strike.  They are thought to be due to the rupture of capillaries under the skin caused by the currentor flash overs just above the skin causing bruising. They were first described by Georg Lichtenberg in 1777 when he noted that sulfur granules on the surface of insulating materials could form fractal like images if a current was applied. 20-30% of those struck by lightning have these figureswhich last 1-3 days.

Benjamin Franklin flew his kite on a stormy day in Pennsylvania in 1752 and  learned that lightning is an electrical discharge creating a current that flows either within a cloud or between a cloud and the ground. Since the upper part of a thunderstorm cloud becomes positively charged while the middle becomes negatively charged a current can flow between the two areas.  

There are several ways to be struck by lightning. In a direct strike the person becomes part of the main lightning discharge channel.  A portion of the current moves along the skin surface and a portion moves through the body along the cardiovascular or nervous systems. Asystole is a common result, however the natural automaticity of the heart may cause a rhythm to resume.    A side flash occurs when lightning strikes a taller object near the victim anda portion of the current jumps to the person. Less current is transmitted to the person and this is probably what happened to our patient since a tree next to his car was struck first and he did not have an exit wound .Ground current is the third way you can be effected by lightning. This is where the lightning hits the groundand travels along the ground.  It enters the body at the closest point to the strike and exits at the point furthest away.  This often kills farm animals.  Conduction  of the lightning strike can also kill people.  In this case the current travels along a metal surface like plumbingor electrical cords and can cause an electric shock. The final way you can be injured by lightning is with a streamer.  Streamers develop as the downward-moving leader approaches the ground.  Only one streamer will rise up to contact the leader but all other streamers in the areacan discharge.  This gives rise to numerous stories of being hit by a “bolt from the blue” since you can be at a distance from the main discharge. A famous case of a bicycle rally in Vail described a participant being hit by lightning under a cloudless sky. 

Lightning causes 4,000 deaths per year worldwide and extensive property damage. Lake Maracaibo in Venezula is the number one spot for lightning in the world (252 strikes per kilometer per year) with the Democratic Republic of Congo also reporting frequent lightning strikes.  Since ideal conditions for lightning include areas where warm moist air mixes with cold air above; these two areas would be ideal.  More lightning occurs over land than over the ocean because sunshine heats land surfaces faster than water.  In the US Florida has the highest number of lightning strikes

Our patient did well.  He initially had fallen from his truck to the ground.  His troponin peaked at 0.35, and CK at 401. He was discharged in two days with no treatment. 


http://en.blitzortung.org/live_lightning_maps.php  real time lightning map

Cherington M, Olson S, Yarnell P.  Lightning and Lictenberg Figures. InternationalJournal of the Care of the InjuredVol 34(5) 2003; 367-371

Domart Y, Garet E.  Lichenberg figures due to a lightning strike. New Englan Journal of Medicine. 343:1536 2000.  Images in Clinical Medicine.

Theodore Gray, TTheo Gray’s Mad Scienc Experiments You Can Do At Home-But Probably Shouldn’t Blanck Dog & Leventhal Publishers, 2009 ISBN 978-1579127916.