Blistering Disorders
Blistering DisordersBlisters :-are accumulation of fluid within or under the epidermis . The appearance of blister is determined by the level at which it form . Intra epidermal blisters :- appear within the prickle cell layer of the epidermis , & so have thin roof & rupture easily to leave an oozing denuded surface ; this tendency is even more marked with sub corneal blisters . Sub epidermal blisters :- occur between the dermis & epidermis , their roof are relatively thick , & so they tend to be tense & intact .
Classification of bullous diseases according to
location of blister in the skin :-the
Classification according to their location
Subcorneal blister:- 1-bullous impetigo. 2-candidiasis. 3-miliria crystallina. 4-pemphigus folacieous. 5-SSSS. Intraepidermal blister:- 1-acute dermatitis. 2-viral vesicle. 3-pemphigus vulgaris. 4-Scabies. 5-friction blister.Subepidermal blister:-
1-bullous pemphigoid. 2- dermatitis herpitiformis. 3-bullous LE. 4- bullous lichen planus. 5-TEN. 6- erythema multiforme.Blistering Disorder
Classification according to cause :- Infection :- bullous impetigo , herpes simplex or zoster , SSSS , & candidiasis . Auto immune :- pemphigus , pemphigoid , dermatitis herpetiformis , bullous LE , & bullous lichen planus . Hereditary :- epidermolysis bullosa . Unknown :- toxic epidermal necrolysis . Miscellaneous :- dermatitis , erythema multiforme , friction blister .Autoimmune Blistering Disorder
These are disorders by which the damage is created by auto antibodies directed at molecules that normally bind the skin . These diseases tend to be chronic & many are associated with tissue bound or circulating Ab. . These include :- Pemphigus . Bullous pemphigoid . Dermatitis herpetiformis . Epidermolysis bullosa . Bullous LE . Bullous lichen planus .
Blistering Disorders
Diagnosis of blistering disorder :- History :- sometimes history helps to reach the diagnosis , as in cold or thermal injury , or in an acute contact dermatitis . Examination :- the morphology or distribution of a bullous eruption gives the diagnosis away , as in herpes simplex or zoster . Investigation :- when the cause is not obvious ( skin biopsy , direct immunoflouresence , indirect immunoflouresence ) .Pemphigus
Pemphigus :- is a chronic lethal autoimmune intra epidermal blistering disease involving the skin & mucous membrane . Acantholysis :- loss of cohesion between epidermal cells caused by circulating IgG antibodies directed against the cell surface of keratinocytes , destroying the adhesion between epidermal cells producing blisters .Pemphigus
Classification of pemphigus :- Pemphigus vulgaris (supra basal blister) pemphigus vegetans (localized) . Drug induced pemphigus . Pemphigus foliaceus (sub corneal blister) pemphigus erythematosus (localized) . Drug induced . Para neoplastic pemphigus .Pemphigus Vulgaris
The most common & severest form of pemphigus , charact. by thin walled flaccid , easily ruptured bullae that appear on either apparently normal skin & mucous membrane or on erythematous base .the bullae soon rupture to form erosions , covered with crusts that have little or no tendency to heal . The healed lesions often leave post inflammatory hyper- pigmentation . It may begin in many ways , but most commonly the lesions appear first in the mouth in up to 60% . During the course of illness , oral mucosal involvement occur in 100% in the form of short lived bullae that quickly rupture in to painful erosions , lips are fissured & crusted .Pemphigus Vulgaris
Also there is involvement of the throat , esophagus , vagina , & penis .The next most common sites are the groin , scalp , face , neck , axillae or genitalia .Nikolsky sign is +ve (there is an absence of cohesion in the epidermis , so the upper layers are easily made to slip laterally by slight pressure or rubbing .male = female .5th – 6th decades .Mediterraneous descent .Pemphigus Vulgaris
Differential diagnosis :- Cutaneous lesions :- bullous pemphigoid epidermolysis bullosa , bullous empitigo . Oral lesions :- oral aphthosis , behcet disease , herpes simplex . Course :- of all form of pemphigus is prolonged even with treatment & mortality rate of pemphigus is still at least 15% .Pemphigus Vulgaris
Diagnosis :- Skin biopsy for light microscopy :- small , early vesicles or skin adjacent to a blister shows an intra- epidermal bulla , supra basal acantholysis , mild - moderate infiltrate of eosinophils . Direct immunoflouresence :- shows deposition of IgG & in most instances C3 in the intercellular space of the epidermis . Indirect immunoflouresence :- detecting serum IgG which is present in all forms of pemphigus reflecting disease activity .Pemphigus Vulgaris
Complication :- Due to high dose of systemic steroid & immunosuppressive drugs . Infections of all types are common . The large areas of denuded skin may become infected . Sever oral ulcers make eating painful . Fluid & electrolyte imbalance (fluid loss & painful eating) .Pemphigus Vulgaris
Treatment :- Admission to hospital . Very high dose of systemic steroid such as prednisolon 80-320 mg\day , the dose is dropped only when new blister stop appearing & taper gradually to maintenance level . Immunosuppresive agents as azathioprine , cyclophosphamide , & methotraxate are often used as steroid sparing agent . Plasmapheresis & intravenous immunoglobulin .Pemphigus
Pemphigus Vegetance :- is a rare variant of pemphigus vulgaris with supra basal cleft & acantholysis , clinically there is vegetative growth in the flexure (excessive cowliflowered like granulation tissue & crusting . Drug induced pemphigus :- mostly due to pencillamine , captopril , pencilline , IL2 , rifampicin . There is less mucosal involvement , most of the cases resolve after discontinuation of treatment .Pemphigus
Pemphigus foliaceus :- in this type there is sub corneal blister , this will lead to appearance of flaccid blister which is rapidly ruptured to form scaly crusted erosions . Mucous membrane is rarely involved . The disease may spread causing exfoliative dermatitis Pemphigus erythematosus :- a localized form of pemphigus folacieus with typical scaly crusted lesion on the malar area of the face & seborrheic area . Para neoplastic pemphigus :- rare type , associated with thymoma or underlying carcinoma , chara. By unusually sever mucosal lesion .Bullous Pemphigoid
Is a chronic sub epidermal autoimmune blistering disease usually occurring in elderly where auto antibodies are directed toward the epidermal basement membrane . Usually affect above 60 years . No known racial or sexual predilection . Etiology :- it is auto immune where auto antibodies IgG class with C3 are directed at the lamina lucida & hemidesmosome producing tense blister .Bullous Pemphigoid
Clinical manifestation :- Skin :- large , tense intact bullae arising on normal or erythematous base , or form large urticarial plaques , most commonly on lower abdomen , inner & anterior thighs , flexor forearms & may occur any where , usually associated with intense pruritus . Eroded lesions from ruptured blisters shows good tendency for spontaneous healing in contrast to pemphigus , on healing leaves post inflammatory hyper pigmentation . -ve nikolysky sign . Mucous membrane is involved in 25% of the cases with erosions & intact blister (less sever than pemphigus vulgaris) .Bullous Pemphigoid
Differential diagnosis :- Pemphigus , erythema multiforme , epidermolysis bullosa aquisita . Diagnosis :- Skin biopsy :- sub epidermal bullae , heavy upper dermal infiltrate of eosinophils . Direct immunoflouresence :- IgG & C3 along basement membrane zone . Indirect immunoflouresence :- circulating auto antibodies against basement membrane zone found in 70-80% of cases & does not correlate with disease activity .Bullous Pemphigoid
Treatment :- Usually self limiting , but may last for months or years . if localized disease could be treated with potent topical steroid . Extensive disease :- systemic steroid as oral prednisolon 40-60mg\day until control disease & then taper gradually . Sometime we add steroid sparing agent & dapson .Dermatitis Herpetiformis
Is a chronic , relapsing , severely pruritic disease with grouped , symmetrical , polymorphous , erythematous-based lesions on the extensor surface with unique histologic , immunologic & GIT criteria . Clinical feature :- charac. clinically by papules , papulovesicular , vesiculobullous , bullous or urticarial lesions . On involution leaves post inflammatory hyper pigmentation Intense itching & burning &their paroxysmal quality provokes scratching to the point of bleeding . Site of predilection are scalp , nuchal area , posterior axillary folds ,elbows, sacral region , buttocks , & knees . Symmetrically arranged lesions , in crops .Dermatitis Herpetiformis
Mucous membrane involvement is rare . Course of disease is life long . Slightly more common in men . Any age could be affected mostly 2-5 decades . Most of the patients have an underlying gluten sensitive enteropathy . Although this may be asymptomatic . Strong association with HLA DR3 , HLA B8 . Differential diagnosis :- bullous pemphigoid , erythema muliforme , scabies , contact dermatits , atopic dermatitis , numular eczema , neurotic excoriation , insect bite .Dermatitis Herpetiformis
Diagnosis :- Skin biopsy :- showed papillary micro abscess with neutrophils & eosinophilic infiltrate & sub epidermal bullae . Direct immunoflouresence :- granular deposits of IgA at the dermal papillae of uninvolved skin . Jejonal biopsy :- sub total vellous atrophy . Treatment :- Gluten free diet , dapson 50 -300 mg\day , sulphapyridine & sulphasalazine .Erythema Multiforme
acute often recurrent inflamm. Disease charac.by target shaped urticarial plaques which are arranged symmetrcally on the palms, back of the hand & feet. Pathogenesis:- immune complex mediated in which IgM &C3 deposition around upper dermal blood vessel.Etiology:- 50% idiopathic 1- viral infection:- herpes, hepatitisA,B,C, AIDs, ORF, polio, mycoplasma pneumonia. 2- bacterial infection:- TB, brucilla, typhoid. 3- fungal infection:- histoplasmosis. 4- Protozoal infection:- malaria, trichomoniasis. 5- Radiotherapy. 6- Drugs:- sulfonamide, pencilline, contraceptive, phenytoin phenothiazine. 7- polyarteritis nodosa, lupus erythematosus. 8- carcinoma, lymphoma, leukemia 9-Sarcoidos