p-Phenylenediamine (PPD) is an important allergen; 5.0% of patients tested positive to PPD when patch-tested, according to the North American Contact Dermatitis Group. Hair dyes are the main source of exposure.
To assess the significance of PPD allergy at the Ottawa Patch Test Clinic.
We assessed the epidemiology of PPD allergies and determined the cross-reactivity with other para-amino compounds. Charts of patients visiting the Ottawa Patch Test Clinic between May 1997 and July 2009 were reviewed.
One hundred thirty-four patients were found to have a contact allergy to PPD; 75.4% were female, 24.6% were male, 13.4% were hairdressers, 18.7% had a history of atopy, 90.3% were sensitized by hair dye, 2.2% were sensitized by henna tattoos, and 7.5% were sensitized by other sources. Positive patch-test reactions to textile dyes were seen in 24.6%, 7.5% reacted to benzocaine, 6.0% reacted to sulfa drugs, 1.5% reacted to isopropyl-para-phenylenediamine, and 1.5% reacted to para-aminobenzoic acid.
PPD is an important source of allergic contact allergy. Our results show a significant relationship of PPD with other related para-amino compounds.
The Ministry of Health and Long-Term Care, in coordination with Cancer Care Ontario, records and analyzes wait times for cancer surgery in the province of Ontario. However, this strategy does not include wait times for skin cancer surgery.
The wait times and referral patterns of patients undergoing Mohs micrographic surgery at The Ottawa Hospital (TOH) were examined to better assess the adequacy of access to skin cancer treatment in Ontario.
The records of 101 Mohs surgeries (96 patients) consecutively performed at TOH between June 14, 2010, and October 19, 2010, were reviewed. The interval between the date the referral for Mohs surgery was first received and the date of surgery was calculated for each case. The specialty of the referring physician and the postal code of each patient treated were also recorded.
The average wait time between the date of referral and the date of surgery was 122.6 days or 17.5 weeks (median 124 days, 17.7 weeks). Over 75% of patients waited over 12 weeks (84 days) for cancer surgery. All Mohs surgery patients treated at TOH resided within postal districts in eastern and northern Ontario.
The current wait time for Mohs surgery in the Ottawa region is beyond the standard for cancer treatment. Improving access to care and incorporating Mohs surgery into the Ministry of Health and Long-Term Care's Wait Time Strategy might significantly improve this.