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Purpose To describe the clinical and molecular findings of an Italian family with a new mutation in the choroideremia (CHM) gene. Methods We performed a comprehensive ophthalmologic examination, fundus photography, macular optical coherence tomography, perimetry, electroretinography, and fluorescein angiography in an Italian family. The clinical diagnosis was supported by western blot analysis of lymphoblastoid cell lines from patients with CHM and carriers, using a monoclonal antibody against the 415 C-terminal amino acids of Rab escort protein-1 (REP-1). Sequencing of the CHM gene was undertaken on genomic DNA from affected men and carriers; the RNA transcript was analyzed with reverse transcriptase-PCR. Results The affected men showed a variability in the rate of visual change and in the degree of clinical and functional ophthalmologic involvement, mainly age-related, while the women displayed aspecific areas of chorioretinal degeneration. Western blot did not show a detectable amount of normal REP-1 protein in affected men who were hemizygous for a novel mutation, c.819+2T>A at the donor splicing site of intron 6 of the CHM gene; the mutation was confirmed in heterozygosity in the carriers. Conclusions Western blot of the REP-1 protein confirmed the clinical diagnosis, and molecular analysis showed the new in-frame mutation, c.819+2T>A, leading to loss of function of the REP-1 protein. These results emphasize the value of a diagnostic approach that correlates genetic and ophthalmologic data for identifying carriers in families with CHM. An early diagnosis might be crucial for genetic counseling of this type of progressive and still untreatable disease.

The phakomatoses have been traditionally defined as a group of hereditary diseases with variable expressivity characterized by multisystem tumors with possible malignant transformation. The Sturge-Weber syndrome, Klippel-Trenaunay syndrome, and the phakomatosis pigmentovascularis have the facial port-wine stain in common. Numerous pathophysiogenetic mechanisms have been suggested such as venous dysplasia of the emissary veins in the intracranial circulation, neural crest alterations leading to alterations of autonomic perivascular nerves, mutation of the GNAO gene in the Sturge-Weber syndrome, PIK3CA mutation in malformative/overgrowth syndromes such as the Klippel-Trenaunay syndrome, and the twin-spotting phenomenon in phakomatosis pigmentovascularis. Other features linked to the port-wine stain and typical to all of the three conditions are glaucoma and choroidal alterations. Glaucoma can be due to malformations of the anterior chamber or high episcleral venous pressure and in phakomatosis pigmentovascularis it can also be associated with angle hyperpigmentation. The choroid can be thickened in all diseases. Furthermore, choroidal melanocytosis in the phakomatosis pigmentovascularis can lead to malignant transformation. Although the multiple pathophysiological mechanisms still require clarification, similarities in ophthalmic manifestations make it reasonable to classify these diseases in an independent group.

Noteworthy heterogeneity exists in the rare diseases associated with childhood glaucoma. Primary congenital glaucoma is mostly sporadic; however, 10% to 40% of cases are familial. CYP1B1 gene mutations seem to account for 87% of familial cases and 27% of sporadic cases. Childhood glaucoma is classified in primary and secondary congenital glaucoma, further divided as glaucoma arising in dysgenesis associated with neural crest anomalies, phakomatoses, metabolic disorders, mitotic diseases, congenital disorders, and acquired conditions. Neural crest alterations lead to the wide spectrum of iridocorneal trabeculodysgenesis. Systemic diseases associated with childhood glaucoma include the heterogenous group of phakomatoses where glaucoma is frequently encountered in the Sturge-Weber syndrome and its variants, in phakomatosis pigmentovascularis associated with oculodermal melanocytosis, and more rarely in neurofibromatosis type 1. Childhood glaucoma is also described in systemic disorders of mitotic and metabolic activity. Acquired secondary glaucoma has been associated with uveitis, trauma, drugs, and neoplastic diseases. A database research revealed reports of childhood glaucoma in rare diseases, which do not include glaucoma in their manifestation. These are otopalatodigital syndrome, complete androgen insensitivity, pseudotrisomy 13, Brachmann-de Lange syndrome, acrofrontofacionasal dysostosis, caudal regression syndrome, and Wolf-Hirschhorn syndrome.

We report three cases of patients with atypical retinitis pigmentosa (RP): sector bilateral, sector unilateral, and inverse. Clinical and functional features of perimetry, color vision testing, adaptometry, electroretinography, fluorangiography, and audiometry are described. One patient had isolated RP; the others had syndromic RP, combined with defective hearing and celiac disease. Two of these patients were followed for three years and one for 13 years. Their disease courses during the period of observation are discussed.