Case Number : Case 1644 - 13 October Posted By: Guest

Another beautiful set of images from Dr Arti Backshi

Are some of you still having problems logging in/adding comments/enlarging images? If so, I can pass this on to the administrator. 

I see a predominance of catagen and telogen hairs, lack of inflammatory infiltrate, abnormal cornification of IRS and lots of clefts. I think this is a case of loose anagen hair syndrome, the main differential diagnosis is AA that is more frequent in the pediatric population

reviewing the case, It bothers me a bit the high amount of catagen and telogen. Should correlate with trichogram but I favor LAHS over AA

The most striking feature is the excess catagen and telogen together with minimal inflammation. Can be seen in longstanding AA but at such stages, compensatory hypertrophy of seb lobules is usually seen which we do not have here. There is a follicle with excess keratin. There are clefts around hair follicles. I do not c pigment casts but still will raise the possibility of trichotillomania. 

I have commited a mistake when saying abnormal cornification of IRS. It is just abnormal cornification as Mona mentioned, we cannot actually see the IRS in that follicle. Trichotillomania without pigment casts or hemorrhage sounds weird... I think that the only pathology that can show us all the features we see here is AA in a late phase. I have very little experience with alopecia but I would not discard LAHS   

oh dear it is kind of annoying not being able to edit the text of comments anymore. Where we read I mean "us" hope I am not getting banned of the web :D

Raul,

I will have a word with the site guru and see if this can be changed.

Cheers, Geoff

Raul etc,

I have changed settings so that you can edit your postings.

You are currently a limited member and soon you may not be able to post, have you considered membership?

Cheers, Geoff

Alopecia is a difficult area! Some of my trainees who visit this site have suggested that more description of the images would help them to understand the discussion better. So I am going over some of the main morphological findings.

As Raul and Mona rightly picked up, there is excess of telogen and catagen follicle (particularly seen in last 3 images). Normal count is 10-15%, in this case 40-50% of follicles were in telogen/catagen phase. There is another prominent finding seen in image 3, 4 and 5. Remember this is a horizontal section at level of isthmus/infundibulum, so normal anagen terminal follicles at this level should all look somewhat like the central follicle in image 7. The 3 other follicles in that image are clearly abnormal for this level. Any suggestions what these represent??

Also, Mona rightly pointed towards absence of sebaceous hyperplasia. Infact, there are hardly any sebaceous glands seen at all. Any thoughts why this may be?

Raul, loose anagen syndrome would show clefts between the inner and outer root sheath (or sometimes within inner root sheath), the clefts seen in these images are mainly surrounding the outer root sheath and stroma. Some fragmentation of IRS is a common artifact of processing (noted in lowest follicle in image 6). Also, almost all follicles would be anagen in LAHS, which is not the case here. (If it helps, LAHS was not a clinical consideration either).

Will leave it for another day. More comments welcome!!

The other three follicles in image 7 are vellus or vellus like (miniaturized follicles). So we also have increased vellus to terminal hair ratio which I missed first and this is not seen in trichotillomania but favors longstanding AA especially with the clinical presentation in an infant. 

The absent sebaceous glands usually points to a scarring process and is also seen in psoriatic alopecia, both causes are not present here so since this girl is a 2 year old, can one explain this absence of seb glands by an age related state of sebaceous gland atrophy?

i think of Congenital Triangular Alopecia .

42 minutes ago, Arash said:

i think of Congenital Triangular Alopecia .

I thought of it when I found the increased vellus hairs but will it explain the increased catagen and telogen? 

I have two questions: is sebaceous glands loss an usual finding in scarring alopecia? So we couldn't find this in non scarring alopecia...

is there any mild peri follicular scar or am I wrong?

7 minutes ago, vincenzo polizzi said:

I have a question: is sebaceous glands loss an usual finding in scarring alopecia? 

Yes vincenzo is something seen usually. But we all agree that this case is not scarring alopecia as scars are absent and perifollicular fibrosis. As mona mentioned sebaceous hypoplasia/aplasia can be seen in psoriatic alopecia. I did not find a reference relating age and density of sebaceous glands though. Hormonal levels can play a role and apparently from the history this does not seem to be syndromic. 

6 hours ago, Dr. Mona Abdel Halim said:

I thought of it when I found the increased vellus hairs but will it explain the increased catagen and telogen? 

you are right. cant fit everything in this case. i think we should wait for Arti to better clarification.

Thanks for all your excellent comments!

This is a case of chronic alopecia areata.  Well done to Mona and Raul for considering the diagnosis inspite of absent peribulbar inflammation. Mona's second comment wraps up the case beautifully!

The key findings are marked shift into telogen phase and prominent miniaturisation. (The terminal:vellus ratio was 1:1 in this case ; normal is 7:1). This combination should always make one think of chronic AA. The main differentials of high telogen counts ie  telogen effluvium and traction alopecia do not show miniaturisation. Conversely the other main cause of miniaturisation ie androgenic alopecia will not show such high telogen counts (although borderline increase of 15-20% not unusual). Temporal traingular alopecia has a typical distribution and again one would not expect telogen shift in this entity. Remember, that chronic AA often lacks peribulbar inflammation, so undue reliance on this one feature can lead to underdiagnosis. AA was the clinical impression too in this case.

 For the beginners in alopecia pathology, vellus/vellus like follicles have their bulbs in upper or mid reticular dermis (seen in images 1 and 2) and on horizontal sections are recognised by follicles with inner root sheath thickness greater than or equal to the hair shaft diameter. (image 7).

With regards to Vincenzo's question...absence of sebaceous glands is a usual feature of scarring alopecia and one that I find quite useful. But there are caveats...psoriatic alopecia being one them. I was puzzled by paucity of sebaceous glands in this case, which is clearly not a scarring process clinically or histologically. I reached the same conclusion as Mona that the sebaceous atrophy is due to the age of the child. Kazakov's textbook (of adnexal tm) discusses the evolution of sebaceous glands rather well. (pg 333). ...'In the newborn the sebaceous glands are fully developed but atrophy in the ensuing months due to drop in maternal androgens to become a mantle (an immature sebaceous gland) They again become hyperplastic at puberty'. In some of the levels in this case, one could see atrophic mantles surrounding hair follicles.

Do apologise for the excessively long posts, but I do find alopecia pathology rather fascinating!!

Thanks dear Arti for your perfect explanation.

please consider to post more alopecia cases. i think we need more !

So ,you mean because of prominent increase of Telogen/catagen hair we should think of chronic AA...

In fact in AA we have more Telogen/catagen hairs than conditions like Telogen effluvium.

Yes, completely agree, Arash. Chronic telogen effluvium usially shows milder excess of telogen counts and counts in excess of 40-50% would be unusual for this entity, whereas this is the norm in chronic AA. In typical cases, the clinical would be fairly distinctive (diffuse thinning in TE vs patch of hair loss in AA) . The problem comes in the (less common ) diffuse forms of alopecia areata.....but that is a discussion for another day!