The clinical features of KIDAR include:
Skin abnormalities
- Ichthyosis
- Erythroderma
- Palmoplantar keratoderma
- Sparse hair, with or without a wiry texture
- Thick yellow plate-like scale on scalp
- Sparse or absent eyebrows
- Excessive creases over palms and soles (in some patients)
- Anhidrosis (in 1 patient)
Hepatic abnormalities
- Hepatopathy (in some patients)
Gastrointestinal abnormalities
- Enteropathy (in some patients)
Neurological abnormalities
- Global developmental delay
- Intellectual disability
- Hyperreflexia (in some patients)
- Sensorineural hearing loss – this can be profound requiring cochlear implantation
- Photophobia (in some patients)
- Structural brain abnormalities (in some patients):
- Cerebral atrophy
- Thin corpus callosum
Facial dysmorphism (variable, mild; in some patients)
- Frontal bossing
- Hairline recession
- Ectropion
The following features were observed in a case report of an adult patient with KIDAR:
- Severe corneal scarring
- Gingival recession
- Fissured tongue
- Tooth loss and poor calcification of teeth
Laboratory abnormalities
- Low serum copper
- Low ceruloplasmin levels
- Low plasma zinc
- Elevated very-long-chain fatty acids (in some patients)
- Liver profile (abnormal in some patients):
- High alanine aminotransferase
- High gamma-glutamyl transferase
- High alkaline phosphatase
- High bile acids
- Low plasma albumin
- CBC (abnormal in some patients):
- Thrombocytopenia (episodic or persistent)
- Anemia
Skin histology
- Compact hyperkeratosis
- Keratinocyte separation (focal) above the basal layer
- Increased basophilic vesicles in the proliferative layers of epidermis
- Large intracytoplasmic vesicles (on electron microscopy)
Duodenal biopsy and histology
- Mild blunting of the villi
- Mild crypt hyperplasia
- Cytoplasmic vacuolation of the surface epithelium
Other
- Failure to thrive
- Dysmegakaryopoiesis on bone marrow biopsy