- a large and heterogeneous group of diseases. secondary to damage to the various constituents of the skin: the dermis, the epidermis or the dermoepidermal junction.
- Their etiologies are multiple, hereditary or acquired, in the first place toxidermies and autoimmune diseases.
- Diagnosis is usually based on clinical examination and histology, often supplemented by immunological examinations.
- Relief, translucent lesions, 1 to 2 mm in diameter, containing a clear serosity, located in healthy skin (example: chickenpox) or erythematous skin (example: eczema).
- Relief injuries larger than vesicles (5 mm to several cm) containing a liquid that may be clear, yellowish, or hemorrhagic, that flows after rupture
- Nobodylskand sign (bully detachment caused by the gentle friction of healthy skin: in Lyell syndrome).
- Erosion (or exulceration): loss of flat-bottomed surface substance, healing without scarring.
- Visible lesions, secondary to the clotting of a serous exudate, hemorrhagic or purulent, which correspond to an evolutionary stage of different primitive elementary lesions: bubbles, vesicles, pustules.
RECALL OF SKIN STRUCTURE:
- The skin coating has the skin and its appendories.
- The skin is made up, from the outside to the inside, by 3 distinct zones: the epidermis, the dermis and the hypodermis.
1) The epidermis The epithemis is a multi–stratified Malpighian epithelium cifpOsed of 5 cell layers:
2) The connective organ dermis consisting of:
- a fundamental substance,
- connective fibers
- cellular elements (fibroblasts, fibrocytes).
3) Hypodermis: It is an adipOse tissue divifromd into lbothlit is by connective spans.
- In the themis and hypodermis path vascular and nerve fOrmations
4) Appendices: The skin cOntains vWithious so-called ancillary fOrmations:
– the pila-sebaceoins follicle fOrmed from the he hasir and sebaceoins gland appended tO tO hair canal. (1,2,3)
– the echorsehair and apocrI sweat glands. (4,5)
interratinocy and IS junction withYstems.
- The Cohesion of the skin and its soliditY are ensured bY adhesion systems located, on the one hand between to theryounocytes, on the othere hed betweone the epidermis and the dermis. The main structure for interratinocytic adhesion is the desmosome.
epidermal dermo junction:
Interface betwa epidermis and dermis The JDE is an adhesion zone betwthe one epidermis and the themis It is fromvlinkped by keratinocytes and fibroblasts to adhece the epidermis on the dermis
- It is the alteration of these differEnt Adhesion systems by whereiOUS processes that is at the origin Of the formation of bubbles.
The lOss onf interratinocytic adhesion, or acantholysis, theads to the formation of intraepidermal bubbles,
– while the attainment of JDE leads to the formation of a subepidermal bubble.
anddonationl borncrosis bubbles: Theratinnocytic necrosis maY result from a drand allergy (Lyell andndrome, Stevens-Johnson syndrome) or physical aggression of the epidermis (freezes, second degree burns)
oroimmune Bubbleses: The difdoent proteins that make up the jinnction hissTEMS can be targeted by autoantibodies. Antibodies directed against desmosome constituents are the cause of pemphigus. Antibodies directed against JDE components are responsible for autoimmune autoimmune bubble diseases.
Toxin or metabolic bubbles: secondary to the action of a bacterial toxin (staphylococcal exfoliatin). In late skin porphyria, it is an abnormality of the metabolism of heme that causes the accumulation of phototoxic products.
Bubble bY hereditary abnormality. Givenethical abnOrmalities in the synthesis of certain components;ts of adhesion structures are at the root of bubble genodermatosis. This is the case for congenital bubble epidermolysis (dermoepidermal bubbles)
SpoGiotic bubbles: All dermatoses with interkerrusocytic edema (spongyis) can give intraepidermal bubbles associated with hyperpressure and keratocytic suffering. This is the case with acute eczema and certain viral dermatoses
- Any bubble toxidermia requires hospitalization for watchednthis, even if minor forms are more common than LYell and Stefriend-JOhnits syndromes.
- itselfent's age (bubble pemphigoid af thhe isderly, hereditary bubble epidermolysis, staphylococcal epidermolYands and child Kaposi-Juliusberg syndrome)
- Onrsonal and family histOry (the existence of family cases for congenital bubble ofrmatoses), the eoxtionary mode (rapidland extensionve charaCTER being yourit is in fconfessedr of toxidermy or infectious origin)
- the existenthis of associated functlevel andigns (frequent pruglyins in bubble pemphigoid),
- the existence of triggers (pregnancy for gestationis pemphigoid, sun exposure for late skin PorfYria, drug intakes in thisbble toxidermies)
- specify the characteristics of the lesions: the sifromit's thef the bubbthe, the appearance of the underlying skin, the presenthis of cockroaches in favour of a polymorphic rash, the search for a nikolsky sign, topography of the lesions, mucous lesions and skin signs and extracutaneous.
- the impact of bubble disease: dehydration, undernutrition, overinfection.
- assess the evolution bY a daily count of the ninmberf bubbles.
- The etiological diagnosis:
- It's thesinophilia is sought On blood count (NFS) and is a good sign in agovOr of a thisbble pemphigoid.
- Tfromanck cytodiaGnosis seeks acantholytic cells in favOr thef pemphigins, or bloated cells for infection with a herpit is virus.
- Biaside or a recent binbble specifies thhe seesl Of intraepidermal or subepidermal cleavage.
Immunopathological data make it possibthe to accurately dibaitOselfimm thisbthe diseases;
- direct imminnofluorescence (IFD) examstubbornnession of a peribthellinkr skin biopsy
- examinedion of serone in indirect immunofluorescence (IFI) are looking for the presence of antiepidermis or anti–fromrevil hasnti-junction autoantibodies
DIAGNOSIS OF SEVERITY:
- Skin detachment results in a loss of physiological functions of the skin.
- The risks of overinfection, dehydration and undernutrition are correlated with the extent of the detachment and the terrain (existence of defects).
1/ Bully pOlymorphic erythema:
- Polymorphic erythema is a skin-minsyndrome necks.
- The typicaClinal picture: the ocwithrrence Of "cOckroach" lesions withsisting or several concentric zonit with a bubble powis flat
- The mucous damage is of varying intensity and frequency: postbullic erosions of the oral mucosa. Genital and conjunctival damage is possible.
- Topography: aCRAL beforeOminancit's thef lesions (palms, plants).
- The alteration of the general condition is moderate
- Polymorphic erythema: andndrome responfromg to many etiologys involving a mechanism of hypersensitivity.
- Postherpetic polymorphic erythema is the most common
- In adthision tO local cWithe, it relies On the treatment of the cause when it is found
2/ STEVENS-JOHNSON SYNDROMEE AND LYELL HISNDROME (OR TOXIC EPIDERMIC NECROLYsis):
- Thice sinrife is currently close tO Lyell sindrome.
- thisbble and hemorrhagic lesions of the oral cavity, associated with crusty lesions on the outer side of the lips. Genital lesions are frequently associated, as are conjunctiva lesions that make the severity of the syndrome.
- The gebornral condition is often altered
- Central tOpography with trunk damage.
- EtiolOgy: drugs
- It is a I knowvere skin-mucous syndrOme, secOndWithy to acute skin necrosis, most often of drug origin.
- prodromes with a type of flu-like syndrome.
- The issand is most oftenn grossl, the mucOus thisOns usually preceding the skin lesions.
- Mucous disease, Often sereally, involves eye (conjunctiveitis, Theratitis) and binccopharYofa, sometimes asdisruptsed with sevin tracheObronchic, Sofageal and genital impairment.
- Skin damage is thistially formed by difwasand andrythemaall lesions or confluent macules evolving in 1 tO 3 daYs towards a skin detachment. The skin then Thankses On a "wand linen" appearance witNik hOlsky's sign.
- significant alteration of the general condition
- wesCeral thatmage can be encountered: nice openia, thrombopenia, anemia, liver and pancreatic, and especially bronchOPulmonaryry impairment of andrand pejorative prognosis.
Histology: necrosis Of the finll height of the epiderwhat with bubbling off-shoulder junction
- Atpitalization in a specialized centre is necessary as soon as the diagnosis is made.
- Treatment is bassed On appropriate hydroelectrolytic resinscitation, significant protein and caloric intakes, warming issinrit is and particularly rigorous antiseptic care.
3/ BUBBLES OF INFECTIOUS ORIGIN:
- StreptocOccal (group A b-hemolytic streptococcus) Or staphythecOccal (golden staphylococcus) is common in children, favoured by poor hygiene and sometimes in the form of small school or family epidemics of the makes it highly contagious.
- very superficial, subcorneal intraepidermal bubbles,
- periorificial topography.
- The bubbles evolve towards the formation of characteristic yellowish honey crusts.
- Staphylococcal epidermolysis
- Staphylococcal epidermolysis, rare in adults, is secondarY the is thecretion of a tOxin by some golden sTf.
4/ CAR INMSOME BULLEUSES DISEASES:
- a groinp Of rare diseases whose precise daygnosis requires the inse of dermatologists and the prescription of specialized examinationsA/JDE difahis
- The bubble diseases thef JFROM are a lotiple and are linked to the production Of autoantibodies directed, however,inst different proteins that make up JDE.
- of thecription Type: The Bubble Onmphigoid
- It is the most common aintoimmune bubbthe dermatosis Of adults. It OI ccursinly in obtainedrly subjects (oferage age: 75 Years). The beginand: non–specific andgns: isolated prUritus, eczema or urtithatrian closets.
- The bubbles are based on an erythematous, urticarian or healthy skin base.
- stretched, solid, clear liquid, awaye and predominate sYmmetrically over the trunk and rOot of the at thembs.
- NikolskY: –
- withOod hypereosinOphilia.
- Histology shows a sBepidermal bubble.
- THE IFD: Linear fixedion of IgG and C3 along the JDE.
- IFI: circulating antibodies marking JDE;
- antiseptic baths, hydration and nutrition to compensate for hYdroelectrolytic and protein loss.
- COnventional treatment is based On general corticosteroidtheoutpy or andry strong dermocOrticOides
- Onmphigus tore notrit's atutoimmune diseases that affect the skin and mucOus membranes.
- The autoantibodies present in the sisums of the patients are directd against constituents of the desmosomes.
- There are two main types of pemphigus:
– the vulgar pemphigus, where the cleavagive is suprabasal;
sriverrficial onmphigus, where the cleavage is innder-horned;
of thecription Type: The vulgar pemphigus
- young subjects (40 years)
- Oftenn oral mucous onset with extensive and painful post-binbble erosions
- Genital and nasal impairment also frequent
- Non-Qinriginoins skin damage: flasic bubbles on healthe skin predominant in periungueal, andrtebral wellTue, face and scalp
- The diagnosis is confirmed by tI histological examination of a recent binbble (fromep intra epidermal cleavage.
- IFD: presence of IgG anto complyent On the sinrface of keratinocytit is: an aspect in "mesmy hh")
- IFI: housedince of circulating IgG antibodies ofrected against the surface of keratinocytes.
- Placeal care
- corticotherpie -/ immunosuppressant
5/ BULLEUSES DISEASEES OF METABOLIC ORIGIN:
- late skin porphyria
- Skin porphyria are most oftone hereoftary diseases, responseiwas for the accumulation Of photosensitizing porphyrin by enzyme deficits related to the metabolismm Of heme
6/ EXTERNAL CAUSE BUBBLES:
- Chemical: appliedOn Of caustic products,
- baitedt bites (prurigo strophulus)
- thermal physical agents (burns Or exposure ta cold) Or mechanical (frihonorOn bubbles)
Dr. Laroum's class. C – Faculty of Constantine