Parakeratosis with neutrophils
Neutrophils in the Stratum Corneum
Whenever I see this I think of Impetigo, Fungi or Pustular psoriasis and would order a PAS stain.
Munro microabscesses are collections of neutrophils in the stratum corneum.
Other causes include AGEP acute generalised pustular dermatosis, Subcorneal pustular dermatosis and sometimes also in pemphigus foliaceous.
Acropustulosis of infancy and Neonatal scabies can also show subcorneal pustules without the scabetic organism.
View this video on Sub Corneal Pustules
View this virtual slide of pustular psoriasis
Neutrophils in the epidermis can be seen in a variety of inflammatory conditions but remember Acne and folliculitis, Gonococcemia, Necrolytic migratory erythema, Pemphigus erythematosus or foliaceous, Neonatal pustular melanosis, Scabies and Halogenodermas.
If you see Pustules in the epidermis the mnemonic is II
I - Infective Viral, Bacterial, Fungal, Rickettsial, Protozoa
I Inflammatory eg Drugs, Pustular psoriasis, Rare ( Scabies, Necrolytic migratory erythema, Subcorneal pustular dermatosis, Neonatal pustular melanosis, Erosive pustular dermatosis, Acrodermatitis enteropathica, Halogenodermas)
