Fue Franklin el primero en describir la psoriasis?

J.S. Duplessis. Retrato de Benjamin Franklin (1785)

Joseph Siffred Duplessis (1725 -1802) Retrato de Benjamin Franklin (1785)  Óleo sobre tela Smithsonian National Portrait Gallery, Washington

Joseph Siffred Duplessis fue un pintor francés que se especializó en la realización de retratos. Había nacido en Carpentras (cerca de Aviñón) y tras realizar estudios en Roma y Lyon, se instaló en París (1725), donde fue admitido en la Académie de Saint-Luc. 

Muchos de sus retratos de personajes célebres alcanzaron la fama, popularizándose en grabados y reproducciones. Entre ellos hay que recordar los de la Delfina (1771); del rey Luis XVI con ropa de coronación (1776); el del compositor Gluck (1775); los del financiero Necker; o el del conde Angiviller. 

Pero entre todos ellos destaca este retrato de Franklin, tal vez el más representativo y conocido de los que se hicieron. Este retrato fue reproducido múltiples veces en grabados en sellos y también en los dólares de papel. 

Benjamin West:
Benjamin Franklin descargando electricidad del cielo (1816 circa)
Philadelphia Museum of Art

Benjamin Franklin (1706 - 1790) fue un científico, inventor y político estadounidense considerado uno de los padres fundadores de su país, al firmar la Declaración de Independencia de los Estados Unidos. Su obra como científico fue muy relevante. Destacó en la investigación de la electricidad. A él se deben inventos como el pararrayos, el horno de Franklin o chimenea de Pensilvania, las lentes bifocales, uno de los primeros catéteres flexibles o el cuentakilómetros. 

Conocemos muchos datos sobre la vida de Franklin ya que comenzó a escribir su autobiografia a los 40 años. Era miembro activo de la masonería y mantuvo también múltiples actividades filantrópicas, como la creación de la   primera biblioteca pública de Filadelfia, la fundación del primer hospital de la ciudad y la de la Universidad de Pensilvania. 

Benjamin Franklin en Londres (1767)

Sus notas autobiográficas también nos han dejado el testimonio de sus enfermedades, especialmente diversas alusiones a su psoriasis en los años 1777 y 1780. En aquel momento, la psoriasis todavía no estaba bien individualizada como enfermedad. Franklin se refería a su psoriasis como caspa (y a veces como Scurff) lo que significa la presencia de finas escamas secas o placas. También se quejaba en algunas ocasiones de prurito y dolor. Al parecer sufrió repetidos brotes de bastante intensidad. A él se debe una minuciosa descripción de la enfermedad, bastantes años antes de que fuera descrita por Robert Willan (1808) y Ferdinand von Hebra (1841), por lo que no falta quien considera que Franklin fue quien describió realmente esta enfermedad, avant la lettre: 

The Scurf appears to be compos’d of extreamly thin Scales one upon another, which are white, and when rubb’d off dry, are light as Bran. When the Skin is clear’d in the Bath, it looks red, and seems a little elevated above the sound Skin that is around the Place; but it is not sore: And in a few Hours after, it becomes dry, and feels stiffned  as it were with the first thin Coat of the new Scurff. . . . The fine Lamina seem to be formed one under another, and not to make an united thick Substance by adhering together. In rubbing them off they separate, like Talc, each having a Polish that shines.   

(Franklin 1777).

He aquí algunos otros escritos de Franklin sobre su psoriasis, en la que vuelve a describir algunos aspectos clínicos y señala su periodicidad estacional: 

1777

I first observ'd a kind of Scab or Scurff on my head, about the Bigness of 
a Shilling [in the early 1770s]. Finding it did not heal, but rather increas'd 
I mention'd it to my Friend Sir J.P. who advis'd a mercurial Water to wash 
it, and some Physic. It slowly left that Place but appear'd in other Parts of 
my Head.

[In 1776] I went to Canada. On the passage I suffer'd much from a number 
of large Boiles. In Canada my Legs swell'd and I apprehended a Dropsy. 
Boils continu'd and harrass'd me after my Return, but the Swelling of my 
Legs pass'd off. The Boils however left round them a kind of dry Scab or 
Scurfiness, which being rubb'd off appear'd in the Form of white Bran.

. . . In my Passage to France Nov. 1776 I lived chiefly on Salt Beef, the 
Fowls being too hard for my Teeth. But being poorly nourish'd, I was 
very weak at my Arrival; Boils continu'd to vex me, and the Scurff 
extending over all the small of my Back, on my Sides, my Legs, and my
Arms, besides what continued under my Hair, I apply'd to a Physician,
who order'd me Bellosto's Pills and an Infusion of a Root...  
I took the Infusion a while, [but] it being disagreable, and finding no
Effect I omitted it. I continu'd longer to take the Pills; but finding my 
Teeth loosning and that I had lost 3, I desisted the Use of them.

I found that bathing stop'd the Progress of the Disorder. I therefore took 
the Hot Bath twice a Week two Hours at a time till this last Summer. 
It always made me feel comfortable, as I rubb'd off the softned Scurff 
in the warm Water; and I otherwise enjoy'd exceeding good Health.

. . . In July the Disorder began to diminish, at first slowly, but
afterwards rapidly; and by the Beginning of October, it had quitted
entirely my Legs Feet Thighs, and Arms, and my Belly, a very little
was left on my Sides, more on the small of my Back, but the whole
daily diminishing. I observ'd that where there was no Redness under
the Scurff, if I took it once off it did not return. I had hardly bath'd in 
those 3 Months. I took no Remedy whatever and I know not what 
to ascribe the Change to, unless it was the Heat of the Summer, which 
sometimes made me sweat, particularly when I exercis'd. I had five 
Boiles just before the Amendment commenc'd, which discharged a
great deal of Matter. And once my Legs began to swell.

October 3rd 

I ate no Breakfast, but a hearty Dinner, and at Night found my Back 
itch extreamly near the Shoulders which continues to day the 4th. 
I ate some Salted Beef at Dinner yesterday but not much. I wish the 
Cool Weather may not bring on a return of the Disorder.

October 4. 

The Itching continues, but somewhat abated.

October 6. 

Drank but one Glass of Wine to day; the Itching almost gone. I

begin to think it will be better for me to abstain from Wine. My

Dinner to day was Mutton boil'd and Fowl, with a good deal of
Fruit.

October 12. 

I have lately drank but little Wine. The Itching has not return'd. 
The Scurff continues to diminish. But yesterday I observ'd my 
Ancles swell'd. I suppose my having us'd no Exercise lately may 
be the Cause.

January 14, 1779.

The Swelling above mention'd continu'd some few Weeks, being 
greatest at Night, my Complexion at the same time not fresh; at

length the Itching return'd, and a new Set of Eruptions of scurfy

Spots appear'd in many Parts of my Body. My Back had never been

entirely clear'd and the Scurf began to increase there and extend

itself. But it is not yet so bad as it has been, and it seems to spare

the parts that were before affected, except in my Back. The Swelling

has left my Legs, which are now as dry and firm as ever, and I feel

myself otherwise on perfect health, and have as much Vigour and

Activity as can be expected at my Age. So that I begin to be more

reconcil'd to this troublesome disorder, as considering it an Effort

of nature to get rid of Peccant Matter, that might if not so discharg'd, 
break up my Constitution.

January 16, 1780. 

I have enjoy'd good Health ever since the last Date. Towards the 
End of the Summer most of the Disorder in my Skin disappeared, 
a little only remaining on my left Arm, a little under each Breast, 
and some on the small of the Back. I had taken at different 
times a good deal of Dr. Pringle's Prescription; but whether that 
occasion'd the Amendment, or whether it was the Heat of the 
Summer as I suppos'd in October 1778, I am uncertain. The disorder
seems to be now increasing again, and appears upon my hands. I am
otherwise well; my Legs sound; To-morrow I enter my 75th Year. ·