Gaudin O, et al. - In this case series, researchers characterized the clinical and histologic features of severe acute contact dermatitis due to Nigella sativa oil (NSO) and examined the components responsible for such eruptions. Acute contact dermatitis due to N sativa oil seems to be severe, polymorphic, and histologically characterized by epidermal apoptosis. The main agents involved in the pathophysiologic characteristics of this acute contact dermatitis could be thymoquinone and p-cymene. They proposed that practitioners ought to know about such severe reactions to NSO and report these cases to pharmacovigilance authorities.

Methods

• Researchers conducted a case series study of three women (median age, 27 years [range, 20-47 years]) with contact dermatitis admitted to the dermatology department between August 21, 2009 and February 19, 2017.
• All study participants had been referred to the Dermatology Department for acute contact dermatitis due to NSO and had patch tests performed.
• Main outcomes and measures analyzed were clinical and histologic features of the cutaneous eruptions, length of hospital stay, chemical analysis of NSO, and results of patch tests.

Results

• All patients in this investigation had polymorphic skin lesions spreading beyond the area of NSO application: typical and atypical targets, patches with central blisters, erythematous or purpuric plaques with a positive Nikolsky sign mimicking Stevens-Johnson syndrome, or toxic epidermal necrolysis.
• They observed that two patients had pustules and had severe impairment, with more than 15% skin detachment and fever.
• The outcomes of skin biopsies demonstrated epidermal apoptosis characterized by vacuolar alteration of the basal layer, keratinocyte apoptosis, and a moderate perivascular infiltrate of lymphocytes in the dermis.
• Data reported that the results of patch tests using the patients’ NSO were all positive.
• The outcomes of gas chromatography combined with mass spectrometry performed on the NSO of 1 subject identified several constituent substances, mainly terpenes, thymoquinone, linoleic acid, and fatty acids.