Four brothers with mental retardation, spastic paraplegia and palmoplantar hyperkeratosis. A new syndrome?

Abstract

We report a Caucasian family in which four males out of a total of seven siblings are mentally retarded. Three of the affected individuals have spasticity in the lower limbs (spastic paraplegia), pes caws deformity of both feet and an abnormal gait. In addition, they show palmar and plantar hyperkeratosis. The other male sibling does not have spasticity, but his lower limb reflexes are abnormally brisk and he has slight pes cans deformity. He also shows hyperkeratosis of his palms and soles and is less mentally retarded than his brothers. The mother of the affected boys has normal intelligence, but has plantar hyperkeratosis and a strong facial resemblance to her retarded sons. Her three daughters are normal. The pedigree information is compatible with a sex‐linked mode of inheritance and no specific biochemical or cytogenetic abnormality has been found in the affected individuals. There have been no previous reports of hyperkeratosis palmaris et plantaris in other inherited spastic syndromes.

Palmo‐Plantar hyperkeratosis, intellectual disability, and spastic paraplegia in two maternal half brothers: Further evidence for an X‐linked inheritance

“…In conclusion, our report describes two maternal half‐brothers with palmo‐plantar hyperkeratosis, mild intellectual disability, and neurological abnormalities. This phenotype is very similar to the one reported by Fitzsimmons et al []. Further reports will confirm the mode of inheritance and hopefully lead to the identification of the molecular basis of this probable monogenic disorder.…”

“…To our knowledge, the only patients with association of HSP, palmo‐plantar hyperkeratosis, and intellectual disability were reported by Fitzsimmons et al []. They reported a family of four brothers aged from 16 to 35 with intellectual disability, spastic paraplegia with pes cavus and palmo‐plantar hyperkeratosis.…”

Hereditary palmoplantar keratodermas. Part II: syndromic palmoplantar keratodermas – Diagnostic algorithm and principles of therapy

“…Finally, there is a restricted number of multisystem genetic disorders accounting PPK as an additional and often clinically minor feature within a broader dysfunction and extending from a hereditary cancer predisposition syndrome (Fig. ) to disorders with involvement of immune, central nervous and musculoskeletal systems (Table ).…”