Sir, Bullous congenital ichthyosiform erythroderma (BCIE), or epidermolytic hyperkeratosis (MIM# 113.800), is a rare disorder of keratinization associated with blistering in its early phase. It was first described by Jean-Louis Brocq in 1902 as érythrodermie congénitale ichthyosiforme avec hyperépidermotrophie. Although most cases are sporadic, familial cases show an autosomal dominant pattern ...

Porokeratosis is a specific disorder of keratinization that has five clinical types and shows a characteristic 'cornoid lamella' on histopathology. Malignant degeneration has been described in all forms of porokeratosis. To the best of our knowledge, this is the first Indian report of multicentric squamous cell carcinoma complicating porokeratosis.

Darier's disease is a genetic disorder of keratinization with autosomal dominant inheritance. Its appearance is usually in the form of greasy, crusted, keratotic yellow-brown papules and plaques found particularly on seborrheic areas of the body. However, there are some clinical variants showing atypical skin lesions. Here we report an unusual case of Darier's disease, which mainly showed promi...

Granular parakeratosis is a recently recognized disorder of keratinization that is usually confined to intertriginous areas. The histopathologic features are distinctive and diagnostic. Rarely, histopathologic variants such as follicular granular parakeratosis and granular parakeratosis of eccrine ostia have been described. In this report, we describe a rare case of granular parakeratosis mostl...

Papillon- Lefèvre syndrome (PLS) is a rare autosomal recessive disorder of keratinization characterized by palmoplantar hyperkeratosis, periodontopathy and precocious loss of dentition. The exact pathomechanism of these clinical events mainly remains speculative. This paper describes two cases of PLS with classic clinical features and briefly review the relevant literature.

Disseminated superficial actinic porokeratosis (DSAP) is a disorder of abnormal keratinization for which there no standard treatment. Treatment modalities that have traditionally been utilized with varying success include ablative therapies, topical pharmacologic treatments, surgical excision, and retinoids. The underlying pathophysiology DSAP secondary to genetic mutations in the mevalonate bi...

Porokeratotic Eccrine Ostial and Dermal Duct Nevus (PEODDN) is a rare disorder of keratinization that clinically resembles comedo nevus but occurs on the palms and soles and is characterized by cornoid lamella in the histopathology. We hereunder report a young male with mildly itchy papules on the lateral surface of the left foot who was diagnosed with PEODDN upon biopsy of the lesion. We brief...

Dry eye syndrome is caused by a reduction in the volume or quality of tears. Here, we show that pituitary adenylate cyclase-activating polypeptide (PACAP)-null mice develop dry eye-like symptoms such as corneal keratinization and tear reduction. PACAP immunoreactivity is co-localized with a neuronal marker, and PACAP receptor (PAC1-R) immunoreactivity is observed in mouse infraorbital lacrimal ...