I read an article about phototesting in PLE (BJD 2005 153, 1234) by Prof. Schornagel from Utrecht, Netherlands. Authors conclude that
- Optimum number of exposures for phototesting is 4
- Oberving skin reactions for a few days after discontinuation of phototesting can be informative.
Phototesting was +ve in 38 out of 40 suspected cases of PLE. When I was in Manipal, India as a post graduate, we have not succeeded in demonstrating even a single +ve response on phototesting! What could be the reason? Bad technique or dark Indian skin?