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To the Editor: In their letter, Di Rocco et al present an interesting case report of a 4-year-old Italian patient with Gaucher disease exhibiting severe neurologic involvement. This unusual patient supports our contention that Gaucher disease encompasses a continuum of phenotypes, many of which defy classification into the classic three types. Thus, we are not at all troubled that the patient described differs in many ways from those reported in our series.1.Goker-Alpan O. Schiffmann R. Park J.K. Stubblefield B.K. Tayebi N. Sidransky E. Phenotypic continuum in neuronpathic Gaucher disease: an intermediate phenotype between types 2 and type 3.J Pediatr. 2003; 143: 273-276Abstract Full Text Full Text PDF PubMed Scopus (107) Google Scholar This case reinforces the importance of evaluating each patient individually to provide appropriate family counseling and therapeutic recommendations. However, several features of the case presented are puzzling and incomplete. While we will assume that the patient indeed has Gaucher disease, normal control values for glucocerebrosidase activity were not provided and the genotyping was listed as inconclusive. Congenital ichthyosis, which is mentioned, is in fact associated with severe glucocerebrosidase deficiency.2.Stone D.L. Carey W.F. Christodoulou J. Sillence D. Nelson P. Callahan M. et al.Type 2 Gaucher disease: the collodion baby phenotype revisited.Arch Dis Child Fetal Neonatal Ed. 2000; 82: F163-F166Crossref PubMed Google Scholar Although ichthyosis is usually seen with type 2 Gaucher disease, it was actually noted in 2 of our 9 reported patients with the intermediate phenotype. The vertical gaze palsy described is not characteristic of Gaucher disease, but is seen in other lipid storage disorders such as Niemann-Pick disease. Patients with neuronopathic Gaucher disease typically exhibit slowing of the horizontal saccadic eye movements.3.Sidransky E. Tsuji S. Stubblefield B.K. Currie J. FitzGibbon E.J. Ginns E.I. Gaucher patients with oculomotor abnormalities do not have a unique genotype.Clin Genet. 1992; 41: 1-5Crossref PubMed Scopus (21) Google Scholar The degree of motor impairment described is also atypical, especially in light of what is described as normal intelligence. Most patients with neuronopathic Gaucher disease show diffuse background slowing on electroencephalogram (EEG) and an increase in amplitude of the somatosensory evoked potential.3.Sidransky E. Tsuji S. Stubblefield B.K. Currie J. FitzGibbon E.J. Ginns E.I. Gaucher patients with oculomotor abnormalities do not have a unique genotype.Clin Genet. 1992; 41: 1-5Crossref PubMed Scopus (21) Google Scholar, 4.Garvey M.A. Alarescu G. Wong K. Toro C. Hallet M. Schiffmann R. Somatosensory evoked potentials as a marker of disease burden in type 3 Gaucher disease.Neurology. 2001; 56: 391-394Crossref PubMed Scopus (24) Google Scholar Therefore, the specific results of brain stem and somatosensory evoked response testing and a repeat EEG would be helpful. Further neurologic and cognitive evaluation, including testing of whether the patient has brain stem dysfunction, would better define the neurologic status of this patient. Finally, although it is true that many neuronopathic patients, including the series of children described in our report, ultimately develop either myoclonic epilepsy or progressive deterioration and dementia, the allusion to hematopoietic cell transplantation is confusing. There is no evidence that bone marrow transplantation in Gaucher disease significantly reverses or halts the neurologic involvement, and thus it is doubtful that this patient would significantly benefit from such a procedure, especially in light of his current level of neurologic impairment. Gaucher disease phenotypeThe Journal of PediatricsVol. 145Issue 6PreviewTo the Editor: Full-Text PDF