Complete oculocerebrorenal phenotype of Lowe syndrome in a female patient with half reduction of inositol polyphosphate 5-phosphatase.

• 发表时间: 05 2020
• 来源期刊: CEN Case Rep
• DOI: 10.1007/s13730-019-00434-z
• PMID: 31707643
• 文章类型: Case Reports
• 作者列表: Yamamoto K,Hasegawa Y,Ohata Y,Satomura K,Mizoguchi Y,Shimotsuji T,Yamamoto T

关键词: Inositol polyphosphate 5-phosphatase; Lowe syndrome; OCRL gene; Oculocerebrorenal; Renal tubular dysfunction

Mesh: Asians / ethnology genetics; Cataract / congenital; Child; Disease Progression; Female; Glomerulonephritis, IGA / complications; Hearing Loss, Sensorineural / congenital; Humans; Inositol Polyphosphate 5-Phosphatases / metabolism; Intellectual Disability / diagnosis; Kidney Transplantation / methods; Kidney Tubules, Proximal / pathology; Mutation; Oculocerebrorenal Syndrome / diagnosis enzymology genetics; Peritoneal Dialysis / methods; Phenotype; Proteinuria / diagnosis etiology; Renal Insufficiency / therapy; Severity of Illness Index

Abstract

The oculocerebrorenal disorder of Lowe syndrome is an X-linked mutation in the gene oculocerebrorenal syndrome of Lowe 1 (OCRL), characterized by the triad of congenital cataracts, severe intellectual impairment, and renal tubular dysfunction. Manifestations of phenotype in female carriers and patients are extremely rare. We present a female case with congenital cataracts, severe intellectual impairment, sensorineural hearing loss, and renal tubular dysfunction as Lowe syndrome. A 9-year-old Japanese girl visited our hospital due to prolonged proteinuria. Her renal biopsy revealed diffuse mesangium proliferation, sclerosis and dilatation of renal tubules, and mild IgA deposition in the mesangial region. Furthermore, she had congenital cataracts, severe intellectual impairment, and sensorineural hearing loss. Genetic screening did not identify mutations of the ORCL gene encoding inositol polyphosphate 5-phosphatase (IPP-5P) (46 XX, female). However, we found the reduction of enzyme activity of IPP-5P to 50% of the normal value. Furthermore, her renal function had deteriorated to renal failure within a decade. Finally, she received peritoneal dialysis and renal transplantation. We present the oculocerebrorenal phenotype of Lowe syndrome in a female patient with reduced activity of IPP-5P without OCRL gene mutation.