Clinical and molecular genetic analysis of a new mutation in children with Wolfram syndrome: A case report

A 12-year-old Chinese girl presented with gradual vision loss and insulin-dependent diabetes mellitus and was suspected to suffer from Wolfram syndrome (WFS). A series of clinical examinations were performed, as well as direct DNA sequencing to screen the entire coding region of the WFS1 gene in the patient's family, including her parents and a brother. Ophthalmological examination revealed counting fingers/10 cm in the right eye and hand motions/10 cm in the left eye. Ophthalmoscopical examination identified bilateral optic atrophy without any signs of diabetic retinopathy. A hearing test was performed and revealed that the hearing ability for high frequency sounds was decreased. Urinary output in 24 h was >5,000 ml. In addition, a base substitution at c.2411T>C (Leu804Pro) in exon 8 was identified which was homozygous with the patient and heterozygous with the healthy parents and the brother. In the present case, a neuroophthalmology consult performed in the early stages of the disease was crucial for early diagnosis. In addition, this case study highlights the importance of performing a hearing test as well as collecting and analyzing 24-h urine output in patients presenting with juvenile diabetes mellitus patients and optic atrophy without any signs of diabetic retinopathy.