title: Friedreich Ataxia and nephrotic syndrome: a series of two patients.
abstract: BACKGROUND
  Friedreich Ataxia (FRDA) is a neurodegenerative disorder characterized by gait and balance abnormalities, sensory loss, weakness, loss of reflexes, and ataxia. Previously, two cases of FRDA and Nephrotic Syndrome (NS) have been reported. Here we report two additional individuals with NS and FRDA, providing further evidence for a possible connection between the two diseases and focusing on the neuromuscular responsiveness of one individual to corticosteroid treatment, an effect not previously described in FRDA.
  
  
  METHODS
  We describe two patients with FRDA also presenting with NS. The first patient was diagnosed with FRDA at age 5 and NS at age 7 following the development of periorbital edema, abdominal swelling, problems with urination, and weight gain. The second patient was diagnosed with NS at age 2 after presenting with periorbital edema, lethargy, and abdominal swelling. He was diagnosed with FRDA at age 10. Nephrotic syndrome was confirmed by laboratory testing in both cases and both individuals were treated with corticosteroids.
  
  
  CONCLUSIONS
  Nephrotic syndrome may occur in individuals with FRDA, but was not associated with myoclonic epilepsy in our patients as previously described. It is unlikely that this association is coincidental given the rarity of both conditions and the association of NS with mitochondrial disease in model systems, though coincidental coexistence is possible. One patient showed neurological improvement following steroid treatment. Although neurological improvement could be attributed to the treatment of NS, we also identified some degree of steroid responsiveness in a series of patients with FRDA but without NS.
authors.affiliation: Departments of Pediatrics and Neurology, Children's Hospital of Philadelphia, 502 Abramson Research Center, 3615 Civic Center Blvd, Philadelphia, PA, 19104-4318, USA. julianna.shinnick@gmail.com.
authors.forename: Julianna E
authors.initials: JE
authors.lastname: Shinnick
authors.affiliation: Departments of Pediatrics and Neurology, Children's Hospital of Philadelphia, 502 Abramson Research Center, 3615 Civic Center Blvd, Philadelphia, PA, 19104-4318, USA. isaacsc@email.chop.edu.
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Isaacs
authors.affiliation: Department of Physical Therapy, Department of Rehabilitation, Children's Hospital of Philadelphia, King of Prussia Specialty Care and Surgery Center, 550 South Goddard Blvd, King of Prussia, PA, 19406, USA. vivaldi@email.chop.edu.
authors.forename: Sharon
authors.initials: S
authors.lastname: Vivaldi
authors.affiliation: Departments of Pediatrics and Neurology, Children's Hospital of Philadelphia, 502 Abramson Research Center, 3615 Civic Center Blvd, Philadelphia, PA, 19104-4318, USA. Schadt@email.chop.edu.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Schadt
authors.affiliation: Departments of Pediatrics and Neurology, Children's Hospital of Philadelphia, 502 Abramson Research Center, 3615 Civic Center Blvd, Philadelphia, PA, 19104-4318, USA. lynchd@mail.med.upenn.edu.|Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA. lynchd@mail.med.upenn.edu.
authors.forename: David R
authors.initials: DR
authors.lastname: Lynch
mesh_terms: D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000494:pharmacology; D000328:Adult; D015897:Comorbidity; D005260:Female; D005621:Friedreich Ataxia / Q000188:drug therapy / Q000453:epidemiology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009404:Nephrotic Syndrome / Q000188:drug therapy / Q000453:epidemiology / Q000503:physiopathology*
chemical_list: D000305:Adrenal Cortex Hormones