What to do before a bullous dermatosis

0
7532

INTRODUCTION :

  • The conditions whose primary lesion is a : BUBBLE
  • The bubble is an epidermal lifting circumscribed dimension (>0,5cm), filled with a clear liquid.
  • Histologiquement : The bubble may result from cleavage between the dermis and epidermis (bubble subepidermal) within the epidermis (bubble intra- epidermal), or necrosis epidermal.

TO BEHAVE :

1- EXAMINATION :

  • family history of bullous disease.
  • early age.
  • Mode of occurrence and evolution of bubbles.
  • functional signs : pruritus, local pain.
  • Circumstances of appearance : external agents, pregnancy, sun exposure, drug intake.

2- PHYSICAL EXAMINATION :

  • The topography the eruption.
  • The existence of skin lesions related (erythematous plaques or hives, scars).
  • Achieving mucous or lack.
  • Abnormal fragility of the skin friction (signedeNikolsky).

3- ADDITIONAL TESTS :

  • FNS : eosinophilia
  • cytology bubble liquid.
  • Skin biopsy for histological examination and direct immunofluorescence (IFD).
  • Other : NAME, IFI skin cleaved, immunotransfert

4- ETIOLOGICAL DIAGNOSIS :

1- Dermatoses bullous original exogenously :

Agent physique :

  • trauma : friction rehearsals, pression
  • Thermal : burns frostbite
  • Solar (photonics) :" sunburn "
  • drug phototoxicity
  • Photophytodermatose or "phytophotodermatitis"

chemical :

Contact Dermatitis : caustic, allergic

2- Porphyria cutanea tarda :

  • hereditary synthesis of heme deficiency disorder uroporphyrinogen decarboxylase (UPG)
  • An accumulation derivatives porphyrin photosensitizers in the skin

shapes clinics :

There are two forms :

  • An acquired form is revealing middle age often under the influence of a toxic (Alcohol abuse, estrogen drug such, barbiturates, antipaludéens)
  • A familial affecting younger patients.

Cliniquitous :

PCT associates :

  • bullous lesions affecting mainly the back of the hands and sometimes the face, favored by sun exposure and trauma.
  • erosions, scars, of microkystes Abnormal skin fragility.
  • Hypertrichosis malar.
  • Discolored urine (dark red).

Biologie :

  • a hypersidérémie, liver disturbances
  • The diagnosis is confirmed by :
  • Histological study of the epidermal -under bubble and above, the rise of the urinary excretion of type III uroporphyrin.
  • The prognosis is related to the severity of the progressively constituted liver damage.

3– Dermatoses bullous hereditary :

Rares, often expressed in childhood or the early days of life, including epidermolysis bullosa (degree of severity varies, benign forms to lethal).

4Erythema polymorphous :

  • Children and young adults.
  • The diagnosis is clinical :
  • The lesion badges : comprises three concentric zones
  • micro vesicular Crown, o Red Zone dark
  • Bullous central area
  • The topography is suggestive ACRALE : back of the hands, feet, elbows and knees.
  • of the injury mucous as quickly replaced by erosions bubbles painful on the oral mucosa, genital and eye.
  • Fever and general malaise accompany, often, the onset of rash.
  • Histology is suggestive but not characteristic
  • A bubble intra epidermal necrosis keratinocyte
  • The IFD is negative.
  • Its main cause is infectious
  • recurrent herpes,
  • Mycoplasma pneumonia.
  • overall, the prognosis is good with spontaneous recovery

5- bullous Eruptions :

  • Tables clinical appearance and varying severity :
  • Syndromes de STEVENS-JOHNSON
  • LYELL (toxic epidermal necrolysis -NET)
  • These are the most severe forms of drug eruptions because the prognosis is at stake.
  • There is a continuum between Stevens-Johnson syndrome (SSJ) and Lyell-NET syndrome that are distinguished only by the surface of necrotic epidermis, major factor in gravity
  • Lower than 10 % SC in SJS ;
  • Better than 30 % SC in the NET

1  Stevens-Johnson :

  • 10 days after initiation of treatment
  • Fever, eye burns, pharyngite
  • The rash begins on the face and upper trunk.
  • Macules érythèmeuses broadcasting in 2 at 5 j
  • Blisters or bubbles quickly confluent
  • epidermal detachment in "wet towel"
  • Nikolsky's sign +

2- necrolysis epidermal acute syndrome from Lyell :

Cliniquitous :

  • sudden onset, high fever with AEG
  • The rash is first located, is spreading rapidly
  • painful erythema, flattened appearance of large bubbles and large epidermal detachment A scalded appearance
  • SN is positive and shreds of skin are detached at the lower friction.
  • Mucous membrane is constant.

Pronostic :

  • Despite advances in resuscitation, evolution is often fatal by electrolyte disorders and superinfection.
  • The drugs in question : sulfamides ++ ; AINS, salicylés, phenylbutazone, phenobarbital, antibiotics
  • An identical Lyell syndrome can be achieved in infants, young children and adults immunocompromised by Staphylococcus aureus. SSSS Staphylococcal Scalded Skin Syndrome)

6- Bullous disorders Autoimmune :

  • A heterogeneous group of diseases, infrequent and variable prognosis.
  • Their diversity requires the combination of exams Clinic, Anatomopathologique Immunopathologique.
  • Characterized by the presence of autoantibodies directed against :
  • Desmosomes epidermal keratinocyte
  • Structures of the dermo-epidermal.

a) The Dbai intraepidermal : the pemphigus

  • Affecting the skin and mucous membranes
  • The autoantibodies are directed against proteins of desmosomes and are responsible for the acantholyse a can intraepidermal cleavage.
  • There are three main types of pemphigus :
  • pemphigus vulgaris where cleavage is suprabasal,
  • Pemphigus where cleavage is superficial sub-horny,
  • Pemphigus paraneoplastic.

Clinique

  • 50 years but can be at any age
  • Characterized by :

– An early very often on the buccal mucosa : painful and recurrent erosions

– Bullous rash of isolated lesions without pruritus, without erythema under- underlying, signe de Nikolski positive.

  • Diagnosis is based on :
  • Cytodiagnostic (mucous ++) bubble the floor reveals acantholytic cells
  • histology, a bubble with intraepidermal acantholysis
  • The IFD biopsy of the skin or mucosa péribulleuse: deposits of IgG and C3 on the membrane of keratinocytes, taking an aspect in mesh net.
  • In serum, the presence of anti-epidermal intercellular substance antibody.
  • Target antigen is desmoglein, a major component of the desmosome.

b) The pemphigus superficial :

  • erythematous scaly lesions on the seborrheic areas
  • Lack of mucosal lesions.
  • Histology is close to the previous form
  • It can be induced by medicines comprising the radical sulfydryl (D-penicillamine ; captopril)

c) DBAI Subepidermal pemphigoid :

  • The DBAI subepidermal are related to the production of autoantibodies directed against different proteins of the DEJ.
  • On distingue :
  • The bullous pemphigoid
  • The scarring pemphigoid
  • The gestational pemphigoid
  • Dermatitis herpetiformis
  • Linear IgA dermatitis
  • epidermolyses bulleuses aquises

1/  Pemphigoïde bulleuse :

  • This is the most common DBAI
  • After 70 years
  • Intense itching before the eruption
  • An polymorphous rash strained bubbles of varying size on cupboards erythematous papular urticarial
  • The scarcity of mucosal
  • The absence of signs of Nikolski

The diagnostic

  • Une fickle éosinophilie
  • Biopsy with histological sub-epidermal bubble
  • IFD linear deposits of IgG and complement in basement membrane zone.
  • IFI : presence of anti-basement membrane antibodies circulating
  • Two target antigens were identified corresponding to two proteins hemidesmosomes.

2/ cicatricial pemphigoid :

  • It is characterized by an elective mucosal in the elderly :
  • Gingivitis, stomatitis bulleuse
  • Conjunctivitis synéchiante with risk of blindness.
  • The diagnosis is similar to that of bullous pemphigoid.

3/ Dermatitis herpetiformis :

  • The teenager or young adult
  • diffuse itching, long isolated.
  • An eruption of vesico-bubble annular array on closets erythematous papular, symmetrical willingly
  • Associated with gluten enteropathy, usually asymptomatic.
  • Changes in spurts

The diagnostic

  • Histology shows cleavage subepidermal associated with micro-abscess the papillary dermis with neutrophils and eosinophils.
  • DFI's presence deposits granular d'IgA atop the dermal papillae
  • The search for serum autoantibodies is negative.
  • Circulating antibodies antireticulin, antiendomysium,antigliadine et antitransglutaminase
  • The biopsy of the small intestine shows atrophy  villositaire

4/ gestational pemphigoid :

  • 2nd and 3rd quarter often in the periumbilical region
  • May recur in subsequent pregnancies.
  • The fetal prognosis is dominated by the risk of prematurity and low birthweight Fetal. 5/ Linear IgA dermatosis
  • Occurs at any age especially in children
  • Characterized by a deposition of IgA to the IFD.

TO BEHAVE :

  • The severity of the condition must be assessed on the extent of the blistering rash and general condition.
  • All bullous dermatosis extended warrant hospitalization ;
  • epidermal necrolysis and pemphigus extensive.
  • A hydro electrolytic rebalancing.
  • nutritional intake suitable and sufficient
  • Symptomatic treatment consists in evacuating the liquid contents and disinfect

etiological treatment :

The treatment of major diseases autoimmune bullous based mainly on

The corticosteroids locale or General : The prognosis remains reserved mainly due to complications of this long-term treatment in the elderly.

The pemphigoïde scarring is a difficult treatment. The novel immunomodulatory (CELLEPT) have greatly improved prognosis.

The dermatitis herpetiformis : gluten-free diet and dapsone.

The pemphigus is treated with corticosteroids with or without immunosuppressive.