Fishnet appearance in immunoflorescence is seen in: (Repeat)
Ans: A (Pemphigus vulgaris) Ref: Vesiculobullous disorders. In: Thuppa DM. editor Essentials in Dermatology, 2ndedn., New Delhi: Jay pee brothers medical publishers (P) Ltd 2009:114-26 Explanation:Pemphigus is an autoimmune blistering disorder characterized by autoantibody formation against the intercellular cementing substance called desmogleinsThe mechanism of cell separation is called acantholysis- loss of intercellular substance causing separation of the epidermal keratinocytes which become roundeda result in intraepidermal blisterThese large rounded keratinocytes with large nucleus, perinuclear halo and peripheral condensation of cytoplasm are called the acantholytic cells - seen in Tzanck smearTypes of pemphigus:Pemphigus vulgaris (variant-pemphigus vegetans)- most common typePemphigus foliaceus (variant-pemphigus erythematosus; endemic pemphigus or fogoselvagem)Paraneoplastic pemphigusDrug induced pemphigusIgA pemphigusNeonatal pemphigusClinical features:Fluid fdled bullae- rupture - painful erosions with no tendency to spontaneous healingPainful mucosal erosions- oral (most common; almost in all cases in pemphigus vulgaris); genital mucosa, pharynx, larynx,conjunctiva, urethraBulla spread sign/Asboe Hansen sign- positiveNikosky sign- peel ing of skin leaving behi nd erosions when tangential pressure applied over areas of normal looking skin or over bony prominences (other conditions- staphylococcal scalded skin syndrome, toxic epidermal necrolysis)Diagnosis: Tzanck smear- acantholytic cells; histopathology; direct and indirect i mmu noil ore senceTreatment: systemic steroids are mainstay of treatmentAdjuvants- cyclophosphamide, azathioprine, methotrexate, mycophenolate mofetil. dapsone, plasmapheresis, iv immunoglobulins; biological agent- Rituximab (anti CD20)
Pemphigus vulgaris
Bullous pemphigoid
Dermatitis herpetiformis
Darier disease
Pemphigus