Absent stratum granulosum

Absent Stratum Granulosum                            See DX Path for details of the conditions below

This is seen in ichthyosis vulgaris and under a porokeratotic cornoid lamella.

Ichthyosis vulgaris

under a cornoid lamella 

There is also hypogranulosis seen in any disorder with marked parakeratosis particularly psoriasis. It is also seen in Necrolytic migratory erythema, Acrodermatitis enteropathica and Pellagra. It is also a feature of normal mucous membranes.