Case Number : Case 1759 - 23 February - Dr Arti Bakshi Posted By: Guest

Storm Doris is assaulting the UK today, not good dog walking weather, so take a break and give Dr Arti Bakshi's Spot Case an examination and see what diagnosis you arrive at.

Geoff Cross - DermpathPRO Projects

Looks llike a diffuse palmoplantar keratoderma with acantholytic features. Here a nice article that could be related to the congenital heart disease mentioned. Maybe Carvajal or Naxos syndrome depending on the heart disease.

This is a tricky case for me: on the one hand the histology is consistent with a striated PPK ( acantholisis associated with hype rkeratosis and acanthosis ) on the other hand the clinical description is of a diffuse thickening of the palmoplantar skin...

Very nice article, Raul. Thanks!

Now the tricky case has become a beautiful case for me,and I've learnt another pathological chapter...

Both Raul and Vicenzo doing very well! Could I, at this point, ask a very basic morphological question from everyone. Would you consider the changes in the last 2 images as representing acantholysis or spongiosis??, its a dilemma that I went thru looking at this case......please feel free to answer this, even if you dont want to comment on the actual diagnosis!

I'm sharing the same Arti's dilemma now ( before it was acantholysis for me, after the Arti's question I changed to spongiosis, and now...many doubts. The partially separated cells show a different cytoplasmic stain and some are lightly rounded and condensed...but it's an impression. May be a spongiosis instead, because there isn't any cells single isolated and intercellular connections are evenly obvious...

Agree with Raul that this is mostly syndromal PPK with cardiac abnormalities...

As for Arti's question, I think most of the cells have more or less rounded countours favoring acantholysis. There is minimal infiltrate and no exocytosis. I think it is acantholoysis (hereditary non inflamatory keratinocyte dyscohesion)

I have the same opinion as Mona acantholysis for me. The presence of intercelullar bridges can be tricky as we are taught that they are evident mainly in spongiotic patterns. However if you check ancient cases of Hailey Hailey disease here and here you will see that some of the cells can still show intercellular bridges. Another point is that spongiosis is rarely well delimited within the epidermis as we see here (maybe in some cases of miliaria cristalina?)

I didn’t find any sign of inflammation, so agree with palmoplantar keratoderma (hyperkeratosis palmaris et plantaris).

About Arti’s query, spongiosis means intraepidermal intercellular edema, recognized microscopically by widened spaces between keratinocytes, chiefly in the spinous layer. Acantholysis results from dissolution of intercellular connections of the epidermal cells with loss of cohesion between them. In the images above, the intercellular bridges of the keratinocytes do not appear elongated and stretched as would be expected in spongiotic reactions. Actually, the epidermal cells have round shapes and are separated from one another, evincing their disadhesion due to destruction of the intercellular attachment, namely, an acantholytic process. 

Great discussion!

This is palmoplantar keratoderma, ofcourse. The patient was found to have Desmoplakin (DSP) gene mutation. His brothers and father also have PPK and one of his brothers has ARVD. None have woolly hair though.

With regards to acantholysis vs spongiosis, I have to admit I found it quite tricky in this case. To compound matters, there were also fungal hypahe in the stratum corneum, indicative of fungal superinfection. (will ask Geoff to add an image). One of the dictums with PPK is that presence of spongiosis should prompt a PAS stain to look for fungi! But I agree with the comments above that there is complete lack of inflammation which would be odd for a spongiotic process. To my eye, there was stretching of intercellular bridges...but Raul's comment is pertinent in this regard that one has to be wary of this feature in early stages of acantholysis. From a pathogenetic point of view this makes sense (particularly in hereditary cases)  as the keratinocytes start separating off from each other due to weakened junctions even before they are completely lost. I also agree that there is some early rounding up of keratinocytes, again favouring acantholysis. In this case, it doesn't matter as the mutation is already known, but diagnosing an  acantholytic form of PPK can help point towards the underlying mutation. 

Well done all and thanks for all your comments! 

I can't see very well but there might be also a secondary dermatophyte infection.

Great case!

I think there is clear cut spongolysis (you heard it here first folks!).

Ha! ha!...I like that term!