Case Number : Case 939 - 28th January Posted By: Guest

[img]https://dermpathpro.com/uploads/spot_diagnosis_comment_img/CASE939_Image%2009.jpg[/img]

[img]https://dermpathpro.com/uploads/spot_diagnosis_comment_img/CASE939_Image%2010.jpg[/img]

Possibly she is taking minocycline, minocycline induced pigmentation.

Agree: minocycline induced pigmentation.

I don’t think this is minocycline-induced pigmentation since it is negative for Prussian blue, but I agree this is postinflammatory pigmentation due to photosensitizing agent.

There is a report about a type IV minocycline induced pigmentation that was confined to acne scars and was negative for iron stain but positive with calcium stain. Could it be this case.

http://www.ncbi.nlm.nih.gov/pubmed/14723711

I think this is a form of Minocycline hyperpigmentation. By the way, I did not think there was calcium deposition on Alizarin Red S or von Kossa.

from my report:

[b]-- HYPERPIGMENTATION [/b]
[b]COMMENT:[/b] The presence of hyperpigmentation with Fontana-Masson indicates melanin hyperpigmentation in the basal layer, presumably from minocycline, which has been described as "type III". Other types of pigmentation with minocycline use include a hemosiderin and iron chelate of minocycline (type I) and a metabolite protein complex of chelated iron and calcium (type II). I see neither hemosiderin nor calcium deposition in this skin, and thus presume, by default, that the pigmentation is due to melanin in the basal layer of the epidermis.


[b]And from Weedon (2010):[/b]

[u][b]Type I: [/b][/u] bluish-black pigmentation of scars and old inflammatory foci, including sites of immunobullous diseases, related to hemosiderin or an iron chelate of minocycline, a variant of this [b](proposed type IV)[/b], with blue-gray pigmentation of acne scars on the back was characterized by calcium-containing melanin deposits within dendritic cells and in an extracellular location.

[u][b]Type II:[/b][/u] blue-gray circumscribed pigmentation of the lower legs and arms due to a pigment which is probably a drug metabolite–protein complex chelated with iron and calcium. The recently reported cases with deposits of pigment localized to the subcutaneous fat of the lower extremity appear to be a different type [b](proposed type V)[/b].

[u][b]Type III:[/b][/u] a generalized muddy brown pigmentation due to increased melanin in the basal layer, and accentuated in sun-exposed areas.