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Introduction: Riboflavin Transporter Deficiency (RTD) is a rare neurological disorder characterized by pontobulbar palsy, hearing loss, and motor cranial nerve involvement. SLC52A3 and SLC52A2 mutations are causes of RTD. SLC52A2 mutations are usually found in childhood onset cases. Fifteen Iranian RTD diagnosed patients without SLC52A2 mutations have been previously described. We aimed to identify causative mutations in two childhood cases. Methods: We recruited patients with diagnosis of BVVL. Comprehensive clinical evaluations were performed on the patients. SLC52A3 and SLC52A2 genes were PCR-amplified and Sanger sequenced. Candidate disease causing variations were screened for segregation with disease status in the respective families and control individuals. Results: A novel homozygous SLC52A3 mutation (p.Met1Val) and a heterozygous SLC52A2 mutation (p.Ala288Val) were both observed in one proband with typical RTD presentations. The aggregate of presentations in the early stages of disease in the second patient that included weakness in the lower extremities, absence of bulbar or hearing defects, prominent sensory polyneuropathy as evidenced in electrodiagnostic studies, and absence of sensory symptoms including sensory ataxia did not prompt immediate RTD diagnosis. Dysarthria and decreased hearing manifested later in the disease course. A novel homozygous SLC52A2 (p.Val314Met) mutation was identified. Conclusion: A literature search found recent reports of other atypical RTD presentations. These include MRI findings, speech understanding difficulties accompanied by normal hearing, anemia, and left ventricular non-compaction. Knowledge of unusual presentations lessens the chance of misdiagnosis or delayed RTD diagnosis which, in light of favorable effects of riboflavin supplementation, is of immense importance.

Background: CD59 deficiency is a congenital mutation disorder in complement pathway which can present with various manifestations. Case presentation: Herein, we presented an adolescent 16-years-old girl with recurrent attacks of Guillain-Barre in early childhood and then recurrent attacks of angioedema, paresthesia, and myelitis. Finally, she presented with quadriplegia, malar rash, proteinuria, lymphopenia, and high titer of antinuclear antibody. So, the patient developed systemic lupus erythematosus. Furthermore, we performed whole exome sequencing which revealed homozygote mutations in CD59 for the patient and heterozygote one for her parents. CD flow cytometry showed less than 1 percent expression of CD59 on the surface of the patient’s peripheral blood cells confirming the disorder. So, she had CD59 deficiency. The patient’s episodes were managed with plasma exchanges, corticosteroids, Cyclophosphamide, and Mycophenolate Mofetil which induced and maintained remission. Conclusion: CD59 deficiency can be presented with various clinical features such as neurologic, hematologic, dermatologic, and rheumatologic problems including systemic lupus erythematosus.