title: Subtenon injection of natural leukocyte interferon α-2a in diabetic macular edema: a case report.
abstract: BACKGROUND
  To report the effect of subtenon injections of natural leukocyte interferon α-2a (IFNα) on best corrected visual acuity (BCVA) and central macular thickness (CMT) in a patient with diabetic macular edema (DME).
  
  
  METHODS
  A 66-year-old man affected by DME, with glycated hemoglobin (HbA1c) at 6.9%, refractory to laser grid treatment and intravitreal injections of triamcinolone, was selected to receive a cycle of three subtenon injections/week of IFNα (1×106 IU/ml). BCVA and CMT, using spectral domain ocular coherence tomography (SD-OCT), were evaluated preoperatively and at 1 week, 1 month, 4 months, and 1 year postoperatively. BCVA and CMT were significantly improved at 1 week after the three injections (20/200 vs. 20/40 and 498 μm vs. 237 μm, respectively). BCVA remained stable during the 1-year follow-up. CMT was slightly increased, but was still lower than the baseline value (215 μm, 255 μm, and 299 μm during the follow-up visits). No adverse events were recorded, with the exception of mild subconjunctival hemorrhage at the injection site.
  
  
  CONCLUSIONS
  IFNα, with its immunomodulatory, anti-proliferative and anti-angiogenic actions, was effective in improving BCVA and reducing CMT in refractory DME. Further randomized controlled studies are required to assess the effect of IFNα alone or in combination with other therapies for DME treatment.
authors.affiliation: Department of Specialized, Diagnostic and Experimental Medicine, Ophthalmology Unit, University of Bologna, S, Orsola Malpighi-Hospital, Pelagio Palagi 9, Bologna 40138, Italy. mauro.cellini@unibo.it.
authors.forename: Mauro
authors.initials: M
authors.lastname: Cellini
authors.forename: Nicole
authors.initials: N
authors.lastname: Balducci
authors.forename: Ernesto
authors.initials: E
authors.lastname: Strobbe
authors.forename: Emilio C
authors.initials: EC
authors.lastname: Campos
mesh_terms: D000368:Aged; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage*; D003930:Diabetic Retinopathy / Q000188:drug therapy*; D006801:Humans; D007155:Immunologic Factors / Q000008:administration & dosage*; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage*; D058449:Intravitreal Injections; D008269:Macular Edema / Q000188:drug therapy*; D008297:Male; D011994:Recombinant Proteins / Q000008:administration & dosage; D016896:Treatment Outcome; D014792:Visual Acuity / Q000187:drug effects*
chemical_list: D020533:Angiogenesis Inhibitors; D007155:Immunologic Factors; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins