Histopathologic examination of the skin from a suspected patient commonly shows hyperkeratosis, hyper-granulosis and acanthosis. The presence of cells in the basal and suprabasal layers of the epidermis containing variably sized vacuoles with accumulated lipids is pathognomonic for the<unk> . Classification Adult<unk>  may be divided into the adult<unk>  1 and adult<unk>  2 subtypes. The former stems from mutations in the phytanoyl-CoA hydroxylase (PAHX aka PHYH) gene, on the PHYH locus at 10p13 on chromosome 6q22-24. It was initially believed this was the sole mutation; however 55% of cases are now attributed to mutations in other genes.<unk>  2 stems from mutations in the peroxin 7 (PEX7) gene. This mutation on the PEX7 gene is also on chromosome 6q22-24, and was found in patients presenting with accumulation of phytanic acid with no PHYH mutation. Adult<unk>  should not be confused with infantile<unk> , a peroxisome biogenesis disorder resulting from deficiencies in the catabolism of very long chain fatty acids and branched chain fatty acids (such as phytanic acid) and plasmalogen biosynthesis.
Refsum disease
Shell nail syndrome
Arthritis mutilans
Fuchs' dystrophy
Dentinogenesis imperfecta
Scleroderma
Chyloderma
Xeroderma