Friday, August 31, 2012


Merkel Cell Carcinoma

This one was, as one playa confirmed, very hard.  This was one of my patients at Wilford Hall, and he had, as described, a rapidly growing painless nodule with a slight pinkness to it.  It was, as you see, fairly close to skin colored, as have been roughly half of the Merkels I have run across, and it had the consistency of a firm cyst, but it was not rock hard.  The differential was pretty straightforward:  metastatic disease versus Merkel Cell Carcinoma.  The path was consistent with "trabecular cell tumor" and as a result I gave the dermatopathologist a hard time for speaking in paleodermatologic terms.  

Your clues (use all available clues!!) were the patient's age, the location (an admittedly soft call), the history of rapid growth, the appearance of the lesion itself as above, but most importantly, you should have honed in on the fact that an incisional biopsy was performed, and it was a big incision.  Why would we do that???  Because we wanted a lot of tumor with which to work, in case it was a weird met.  It wasn't.

Thursday, August 30, 2012


Papular Sarcoidosis

Sarcoidosis is a systemic granulomatous disease of unknown etiology which involves botht he skin and other internal organs, including lungs, lymph nodes, myocardium and CNS.

Interestingly, in Europe, the disease is primarily found in rural areas particularly in Scandinavia, and inthe US it happens to be more concentrated in African Americans than the general population.  The lesions are primarily papular, but can be verrucous, erythematous, psoriasiform and alopetic.

The lesions are usually asymptomatic, and concentrated over the head and neck, as well as the upper trunk.  The ddx would include benign adnexal tumors, disseminated deep fungal infection in immunocompromised individuals, or xanthelasma.    The clues in this individual are the papules that are clustered around the eyes and nose, as well as the race.

Wednesday, August 29, 2012


Acrodermatitis Chronica Atrophicans

ACA is a European form of borreliosis, caused by B. afzelii and B. garinii.  It is transmitted by the Ixodes ricinus tick, and causes a morphea-like eruption.  How do we treat it?  One point. It differs from Erythema Chronicum Migrans by its lack of a raised, borrelia-infested erythematous border and by its scar-like appearance.  Had I been confronted by this picture, without any history, I would have said morphea.  

European borreliosis is much less likely to have multiple lesions, versus US borreliosis, and arthritis i s common as a sequela in the US, unusual in Europe.  Also associated with B afzelii and garinii are lymphocytoma cutis, atrophoderma of Pasini and Pierini, and lichen sclerosus et atrophicus.  

Tuesday, August 28, 2012


Dermatomyositis

Although any of the collagen vascular diseases can cause periungual telangiectases (the plural of telangiectasia is telangiectases, not telangiectasias) the classic association is with dermatomyositis, since DM is almost universally associated with those findings, as opposed to scleroderma, SLE, and the other CVDs.  I did, however, give credit for any of the CVDs.  

The most common of the lab tests to be positive for DM is creatine phosphokinase (CPK) but aldolase, Jo-1, ANA or any one of a number of lab tests can be considered to be extremely common with DM.  Name three autoantibodies associated with DM for three points.  Also, abnormal EMGs would be considered an abnormal lab test, as would an abnormal muscle biopsy.

The classic skin findings for DM (other than periungual telaingiectases) are heliotrope rash (swelling and violaceous changes of the upper lids) and Gottron's papules.  Also, photosensitivity, urticarial changes, alopecia, fingertip ulceration, Raynaud's Phenomenon, hyperpigmentation and calcification may occur.

Monday, August 27, 2012


Splinter Hemorrhages

Splinter hemorrhages can be caused by a variety of conditions, and to name a few we have SBE, Acute BE, small vessel vasculitis, trichinosis (my favorite, but then again I love parasitology), small vessel disease due to collagen vascular disease, trauma (the most common reason- by far- for splinter hemorrhages), and antophospholipid antibodies.  This is an excellent example of splinter hemorrhages, and happens to be due to subacute bacterial endocarditis, although I would have bet trauma if I had to throw down a wager.

Sunday, August 26, 2012


Septic Embolus

Bacterial endocarditis can manifest itself in many different ways:  neurologic focal changes due to embolic strokes, evidence of acute heart failure (Jugular Venous Distention, dependent edema, etc.) and, of course, those signs that are near and dear to our hearts, the cutaneous and pericutaneous manifestations.  

Think of it this way:  The infected valve (usually the mitral) has vegetations which are peeled off from time to time by the turbulent flow across the valve, and the emboli float around until they ball-valve into a narrow vessel.  That's where we see them. So, you can have petechiae, such as the conjunctival petechia above, or it can play out as splinter hemorrhages in the nails (note: SBE is not the only way one can get splinter hemorrhages), Osler's nodes (tender digital nodules), Janeway Lesions (nontender palmoplantar nodules) and Roth Spots (retinal hemorrhages).  

The reason for this subtle example is because you, as incredibly astute diagnosticians, won't know it if you haven't seen it.  Remember: we, along with the ophthalmologists, are the detectives in medicine.  When everyone else fails, they come to us.

Wednesday, August 22, 2012


Mycobacterium marinum infection

Well, since I asked for the classic story to go with such a presentation, I hoped most of you would hone in on the appearance, location and classic nature of the lesion.  This is violaceous, on the dorsal hand, multicentric (which implies infection) and does not involve the entire dorsal hand, which shoots down PCT and its imitators.  In my experience, pyoderma gangrenosum is more deep purple, is ulcerated and necrotic.  

So, what's the classic story?  She was cleaning her fish tank, (or working on her boat or scraping barnacles off her dock, etc. ) and got an abrasion; didn't think anything of it and a few weeks later she got these nodules on her hand.  

Now, what's THIS lady's story?  She doesn't remember anything at all.  No trauma, no fish tank, no barnacles.  But, she grew M. marinum, so who knows? Trust your eyes, not your ears!

Tuesday, August 21, 2012


Candidal balanitis/scrotitis

Candidal balanitis is a condition of men who walk around with soggy shorts, are immune compromised, or are uncircumcised.  The picture, although suggestive given the scrotal involvement, is not pathognomonic, and so given the clinical picture, many things, such as psoriasis, Zoon's and even LP could fit the bill.  

The real giveaway on this clinical picture is the scrotitis.  The red, glazed look is classic for candidal involvement, and given the balanitis, it pretty well nails it.  However, if you see an itchy red scrotum, first KOH it because it could be candida or ACD.  If you see a balanitis, you should KOH it to help decide the course of action, as the treatment for most of those conditions is steroids, which if you used steroids would literally drive this guy nuts.  Pun intended.
p.s. Bonus question: How many hits have we gotten on the Derm Challenge blog since its inception? One point if you are within a thousand.



Thursday, August 16, 2012


Bowen's Disease from Pentavalent Arsenic

Patients with multiple SCCIS may have merely gotten their cancers from chronic ultraviolet exposure; like the Sigmund Freud comment "sometimes a cigar is just a cigar",  but sometimes there is a more sinister history behind the disease.

In this particular patient's case, he was an asthmatic as a child, and was given (in the 1960's) an oral solution called Fowler's Solution which contained pentavalent arsenic.  Starting in the '60s, doctors started noticing that many patients treated with Fowler's Solution were getting multiple SCCIS, and later that was extended to people who were drinking arsenic-laced well water as well.  Come to find out, it is primarily pentavalent arsenic that triggers this SCCIS-athon, and I have found multiple SCCIS in patients treated with Fowler's, those who grew up on potato farms (lead arsenate) as well as folks who drank well water.  And I'm just one guy...

The big deal is this:  exposure to arsenic can also predispose to bladder cancer and in some reports, also certain lung cancers as well.  If you have a patient who has multiple SCCIS, ask them about potential exposures, and if they give a positive history, you may want to give their PCPs a heads up.

I gave credit for arsenic, ultraviolet, HPV (including, as one playa noted, occupational exposure to HPV via the World's Oldest Profession).  The real reason for the Q was to point out the connection between arsenic and SCCIS and systemic disease.  I consider multiple SCCIS to be an external manifestation of systemic disease.

I will be OOT from tomorrow through Monday, and so there will be no Friday or Monday Qs.  Enjoy a safe and happy weekend.  I'll be at Charlie Gitto's, an Italian resto on "The Hill" in St. Louis, which was allegedly the originator of toasted ravioli.  It happens to be my favorite Italian joint on the planet. If any of you are in the neighborhood, stop in!


Wednesday, August 15, 2012


Acantholytic Squamous Cell Carcinoma

Acantholytic SCCs tend to be more dangerous than regular well-differentiated SCCs, and it is because of their intrinsic nature.  The cells, which in a normal SCC are connected to one another by intracellular bridges (desmosomes) are loosely connected, if at all.  The resultant SCC is spongier, usually more erythematous and has more os an eroded surface.  Because of this, they deserve more respect than a well differentiated SCC.  We have code words for prioritizing SCCs and melanomas for excision, and melanomas and Acantholytic SCCs get the same code word: ASAP!

These cancers tend to metastasize more frequently, and as most of you noted, they go to the lymph nodes (in this case, the parotid nodes and anterior cervical nodes) and then to the lungs, because that is the most common place for them to be caught in a fine capillary network.

Tuesday, August 14, 2012


Morpheaform Basal Cell Carcinoma

Morpheaform basal cell carcinomas are noted for their hard, scar-like appearance (hence the name) and their notable pathology, which is remarkable for the spikes and strands of BCC, some of which are 1 or 2 cells thick.  They are, as we previously discussed, representative of "worm holes" into the surrounding tissue, and act very differently from a nodular BCC.

So, as I am operating, I often wonder: Is a morpheaform BCC morpheaform because of the way the tmor acts (the genes that are expressed) or is it a "host factor" issue?  My feeling is this: Although the BCC is fundamentally different than a nodular BCC, you gotta figure that they are genetically identical to a nodualr BCC (more on that in a moment) but you also have to figure that it is not just host factors that makes it into a clonal spaghetti that cuts through the reticular dermis and into surrounding tissue.  And, why does it like nerves?

I think it is expression of histones, which dictate the way genes are expressed, which gives the morpheaform BCC its character.  Think of genes as a series of possibilities, and histone expression as a series of options within the genes.  These histones that are expressed lead to the spiky, worm like expression, andalso (see above) the upregulation of fibroblasts to squirt out collagen, as opposed to squirting out mucin, as in a nodular BCC.  

Speaking of nodular BCCs, the best way, by far, to create a morpheaform BCC is to freeze a nodular BCC, which will often create a badass tumor which will grow unimpeded for months or even years before detection.  So, don't do it.


Monday, August 13, 2012


Hypertrichosis


The Weekly World News was a constant source of amusement for most of us during the nineties and the early part of this decade, providing us with such headlines as "Psychic Dogs!" (Boston Terriers that allegedly read their owners' minds), Hillary Clinton Visited By Aliens", accompanied by a pic of our Secretary of State, walking on a beach with an ET-like creature, and my personal favorite, which I bought, "Half-Man Half-Dog Baffles Doctors".  I have to admit, I WAS baffled.  How did they get him into a suit?  Did he tie his own tie, and if so, did he have opposable thumbs or only paws?  The questions just run on and on...

Which brings us to a not-so-baffling question.  What are some of the causes of hypertrichosis?

Well, there are of course many, many causes of hypertrichosis, but here are just a few:

Congenital hypertrichosis: rare, but reported with baby covered with lots of fine hair, which persists later in life.

Congenital hypertrichosis terminalis: same as above, but thicker, termianl hair. "Wolf men"

Nevoid Hypertrichosis:  Circumscribed hair growth, may, if on the lower back, indicate spinal dysraphism

Drug induced hypertrichosis: Too numerous to name here, but one of the most famous is Minoxidil, which later was used to grow and help maintain hair in alopecia syndromes

Metabolic syndromes: e.g. Porphyrias

NAR: (No Apparent Reason)

Please note the difference between hypertrichosis and hirsutism.  Hirsutism is the inappropriate growth of hair in a localized, male pattern area on a female.  Hypertrichosis is not limited to the male pattern areas, and can be on both genders.


Sunday, August 12, 2012


Plague Column, Telč, Czech Republic

The Plague Column in Telč is a nice example of the type of medieval architecture that is scattered all across the southern part of the Czech Republic.  Telč is a beautiful town, with  a picture-perfect town square, a local museum, great restaurants and a dramatic history.  The town is a UNESCO World Heritage site, and as such deserves a visit if you are nearby. For a bonus, name a UNESCO World Heritage site you'd like to visit.

The town square is flanked by beautiful pastel Renaissance and Baroque buildings, and there is a large chateau at one end.  It is in Telč that one really starts to understand the culture clash between the Soviets and the Czechs during the Cold War.  They were from the same planet, but entirely different worlds.  The Czechs celebrated art and architecture in  a way the Soviets could never connect with, and the entire southern Czech Republic is dotted with many towns which are almost as picturesque.  

It is easy for us to forget just how devastating the Black Plague was to Europe.  Nothing really compares to it in modern memory, in that anywhere from 30-60% of Europe's entire population was wiped out during one or the other of the plagues that swept through Europe, probably originating in the Orient and transmitted via rats and their fleas to Europe via the Silk Road.  

The connection between the last question and this one?  Yersinia pestis, the etiologic agent of the bubonic plague, is also one of the organisms which causes a sporotrichoid spread.   


Thursday, August 9, 2012


Sporotrichoid Spread of Nocardia

Sporotrichoid spread describes a clinical syndrome whereby an organism (or tumor) moves up the draining lymphatics of a limb, seeding the lymphatics along the way, leading to inflammatory changes that are manifest (usually) by inflamed nodules.  

The DDx is basically divided into tumors (primarily sarcomas), atypical mycobacteria, typical mycobacteria (tuberculosis), syphilis, Nocardiosis, Cat Scratch Dz, anthrax, tularemia, Yersinia, staphylococcal furunculosis, sporotrichosis and other deep fungal infections such as histoplasmosis, coccidioidomycosis, and North American blastomycosis. And as Tom Lehrer once sang in his famous ditty about the periodic table of the elements, as sung to "The Sergeant Major's Song": "These are the only ones of which the news has come to Haaaarvard, and there may be many others but they haven't been discaaavered!"

Wednesday, August 8, 2012


Necrotizing Fasciitis

Well, here we are again, trying to make sense out of a puzzle.  This patient, who complains bitterly of pain and tenderness, does not fit the usual erysipelas picture, no?  I have never seen an erysipelas patient in significant pain.  Never more than  a 6/10, anyway.  So, what gives?  Why did I emphasize the pain?  Because if you listen to the patient, they might keep you out of the newspapers.  

This patient has necrotizing fasciitis, which is known on CNN and Nancy Grace and FoxNews as the Flesh Eating Bacteria Disease. The main clue that will rock your world is the pain that is out of proportion to the physical findings.  If you palpate around the area, you will have to scrape these patients off the ceiling, because it hurts so badly.  Here's what one (and only one of you got this one) of our playas (Deb from Ohio) had to say: "You had me at "severe" pain.  Necrotizing fasciitis. Something I never want to see again. During my surgical rotation in PA school, I saw this bacteria eat across a woman's chest, giving her a  strep mastectomy!"  

So, the etiologic agent can be strep, or also staph, including MRSA. If you see a frank cellulitis, always be on the lookout for this.  You don't want Nancy Grace tut-tut-tutting on the air about your oversight.

Tuesday, August 7, 2012


Allergic Contact Dermatitis

Allergic contact dermatitis is either the easiest or the most difficult of diagnoses to make.  When you see something that is well-demarcated, linear, or in the shape of an object, think in term of allergic contact.  The external stimulus of the immune system is so at odds with the normal "internally generated" rashes we see that it becomes a relatively easy diagnosis.  Most of the time, that is.  Whether it is from a baseball glove, or soft soaps (the number one contact allergen of the hands in our practice) to nickel dermatitis, there is a pattern to both the rash and the history of onset.  Allergic contact dermatitis is considered a Type IV raction and as such is mediated by lymphocytes, which in turn kick up a spongiotic dermatitis, histopathologically.  For five points, give me a ddx on spongiotic dermatitis.

On the other hand (pun intended) if you are dealing with dyshidrotic (pompholyx) dermatitis, it tends to prominently involve the palms and the lateral fingers, tends to be more chronic in nature with exacerbations (the history was of an acute episode) and I would have a very, very hard time matching up a stone-cold normal thenar eminence with a pompholyx flare.


Monday, August 6, 2012


White Dermatographism

White dermatographism is a physical sign which is classically associated with atopic dermatitis.  It is considered to be indicative of high levels of circulating IgE, which cause a more vigorous reaction than usual dermatographism, which is red.  Dermatographism is differentiated from post-traumatic erythema by being a more exaggerated response to a much less dramatic stimulus. Think of it as physically-induced localized urticaria.  There are other conditions in which white dermatographism has been reported, but the money is on atopic dermatitis.  Incidentally, there is a condition known as "black dermatographism" which is not a true urticarial response, but rather is a staining underneath a ring or wristband of a watch with subsequent linear discoloration of the skin.

Thursday, August 2, 2012


Pellagra

A way to think of pellagra from a dermatologic diagnosis standpoint is to think of it as a photosensitive disease that ends up with scaling, skin thickening and erythema, much like lupus, except only more dramatic.  So, you can see the Casal's Necklace, you can see the Gauntlet of scale, and of course you can see the 4 D's of pellagra, Dermatitis, Diarrhea, Dementia and, if allowed to run its course, Death.  What is one source of Niacin in the diet?  One point.

In this moulage, we see thickening of the skin (just like in Casal's Necklace) in a photodistribution.  Since the skin of the hands is constantly being stretched and flexed, we see the fissuring.  Back in the 1800's when the moulage was made, this was not an altogether unusual presentation, and the astute dermatologist would pounce on a case like this, knowing the answer from across the room.  The dermatologists of old were brilliant diagnosticians, just like you, my astute PAs...