Evaluation of NIR
Patch testing was performed on the patient’s back, as described
elsewhere22. Drugs were mixed in petrolatum 50% w/w
at a final concentration of 20 mg. Readings were done at 48h and 72h
after patch application, and if negative, patients were recommended to
monitor the patch site to detect any eventual reaction. Due to the very
low sensitivity of the test and the lack of systemic effects in cases
with mild reactions5-10, in most instances all BLs
were tested on the same day. In case of negative results, we proceeded
to DPT as described5. DPT was considered positive if
any objective symptoms indicative of an allergic reaction appeared
during the treatment or within 48h after the last
dose5.