Palmoplantar Keratoderma With Normal Intelligence in Tyrosinaemia Ii

Abstract

Melbourne SUMMARYA patient with tyrosinaemia type 11 presented early in childhood with palmoplantar keratoderma and interstitial keratitis. Diagnosis of the metabolic defect and dietary treatment led to prompt resolution of all lesions and she is now well and mentally normal at 21 years. The fact that mental retardation is not a constant, or even frequent, feature of this condition is emphasized.

Plantar keratoderma: a manifestation of tyrosinemia type II (Richner-Hanhart Syndrome)

“… 16 , 18 , 20 , 21 Mental retardation of varying degrees is not a constant feature. 16 , 19 , 20 , 22 …”

Tyrosinaemia type II with diffuse plantar keratoderma and self-mutilation.

“…Mental retardation is the third component of the clinical triad and is increasingly recognized as an inconsistent feature 8 . There appears to be a marked variability in the clinical presentation.…”

“…Noncovalent cross‐linking of tonofilaments through increased intracellular levels of l ‐tyrosine has been suggested to play a part in abnormal keratinization 1 . Diagnosis is established by the findings of high plasma tyrosine and normal plasma phenylalanine levels using plasma high‐pressure liquid chromatography and tandem mass spectrometry, although other methods have been used 8 …”

“…Mental retardation is the third component of the clinical triad and is increasingly recognized as an inconsistent feature. 8 There appears to be a marked variability in the clinical presentation. Tyrosinaemia type II has been described without ocular 7 or cutaneous 9 involvement and associated with normal intelligence.…”

“…1 Diagnosis is established by the findings of high plasma tyrosine and normal plasma phenylalanine levels using plasma high-pressure liquid chromatography and tandem mass spectrometry, although other methods have been used. 8 Early diagnosis and treatment with a low-phenylalanine and low-tyrosine diet is essential prior to development of behavioural changes. Once established the behavioural changes and learning difficulties persist despite dietary control, in contrast to the eye and skin changes, which are reversible, as seen in our patient.…”