- Congenital onset (HP:0003577): A phenotypic abnormality that is present at birth. Evidence: PCS. Frequency: 4/4. (PMID:28575652)
- Epidermal acanthosis (HP:0025092): Diffuse hypertrophy or thickening of the stratum spinosum of the epidermis (prickle cell layer of the skin). Evidence: PCS. (PMID:28575652)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:28575652)
- Erythema (HP:0010783): Redness of the skin, caused by hyperemia of the capillaries in the lower layers of the skin. Evidence: PCS. Frequency: 4/4. Onset: Neonatal onset (HP:0003623). (PMID:28575652)
- Palmoplantar hyperkeratosis (HP:0000972): Abnormal thickening of the skin localized to the palm of the hand and the sole of the foot. Evidence: PCS. Frequency: 4/4. (PMID:28575652)
- Congenital nonbullous ichthyosiform erythroderma (HP:0007479): The term collodion baby applies to newborns who appear to have an extra layer of skin (known as a collodion membrane) that has a collodion-like quality. It is a descriptive term, not a specific diagnosis or disorder (as such, it is a syndrome). Affected babies are born in a collodion membrane, a shiny waxy outer layer to the skin. This is shed 10-14 days after birth, revealing the main symptom of the disease, extensive scaling of the skin caused by hyperkeratosis. With increasing age, the scaling tends to be concentrated around joints in areas such as the groin, the armpits, the inside of the elbow and the neck. The scales often tile the skin and may resemble fish scales. Evidence: PCS. Frequency: 1/4. (PMID:28575652)
- Hyperkeratosis (HP:0000962): Hyperkeratosis is a histopathological term defining a thickened stratum corneum and may be present in many different skin conditions, with many possible overlaps. Hyperkeratosis refers to the increased thickness of the stratum corneum, the outer layer of the skin. Hyperkeratosis is subclassified as orthokeratotic or parakeratotic. Orthokeratotic hyperkeratosis refers to the thickening of the keratin layer with preserved keratinocyte maturation, while parakeratotic hyperkeratosis shows retained nuclei as a sign of delayed maturation of keratinocytes. Evidence: PCS. Frequency: 4/4. (PMID:28575652)
These phenotypes are associated with the disease erythrokeratodermia variabilis et progressiva 4 (OMIM:617526).