Case Number : Case 2227 - 21 December 2018 Posted By: Dr. Richard Carr

Beautiful example of Fox-Fordyce disease

Yes,nice Fox-Fordyce disease and the xanthomatous macrophages next to the infundibular folliculum.

infundibular dilatation/hyperkeratosis and parakeratosis, dilated apocrine glands and periductal /perifollicular xanthomas

fox fordyce disease

Bormate AB, Leboit PE, McCalmont TH. Perifollicular Xanthomatosis as the Hallmark of Axillary Fox-Fordyce Disease: An Evaluation of Histopathologic Features of 7 Cases. Arch Dermatol. 2008;144(8):1020–1024. doi:10.1001/archderm.144.8.1020

Agree. Merry Christmas. 

Yes this was clinically Fox Fordyce. I had only seen it once before visiting another well know lab in Friedrichschafen. I was struck by the cornoid lamella-like parakeratotic plug which has been described. This case also seems to have the cystic dilatation of the apocrine duct at several different depths and the characteristic peri-infundibular foamy macrophages. Knowing the clinical suggestion and not seeing much in the first sections I requested step levels at 150 microns through the block. It really paid off as we can see here. I tend to order step sections at 150 microns for my alopecia cases (after looking at the first 3 levels to see if it's just straightforward), lichen nititdus, any clinical query of "folliculitis" (and then I'll ask for spares x2 at the sets for gram/PAS) and finally dermatitis herpetiformis. Otherwise I rarely request such close steps. For sporotrichosis Weedon mentions doing "serial" sections but I never order serials as Sporotrichosis is not seen in UK to my knowledge. As a side note if there is lot's of pathology and you're not sure what to call it - best show it to someone else as levels rarely help and just show more sections of pathology you don't know how to label!

Forgot to mention doing the 150 micron steps for certain bugs!