Pseudoporphyria is a blistering eruption,usually of the dorsal hands, which is triggered by an exogenous medication. The most commonly implicated of the meds are the NSAIDs, although a whole host of others have been implicated- even aspirin!
The presentation is a blistering eruption on the dorsal hands, and the ddx is EBA, PCT and PseudoPCT. Careful history will rule out PCT, and if there is a history of NSAID use in combination with sun exposure, you've got your culprit.
Ten days into April, we've got a three way tie for first, with a bunch of you one point behind. Keep it up!