eMedicine Specialties > Ophthalmology > Retina

Retinopathy, Birdshot: Differential Diagnoses & Workup

Author: C Michael Samson, MD, Associate Professor, Department of Ophthalmology, New York Medical College; Consulting Staff, Co-director of Uveitis Service, Faculty in Residency Training Program, Director of Uveitis Fellowship Training Program, Department of Ophthalmology, New York Eye and Ear Infirmary; Private Practice, Vitreous Retina Macula Consultants of New York
Coauthor(s): Amro Mohamed Mohamoud Ali, MB, ChB, Consulting Staff, New York Eye and Ear Infirmary; C Stephen Foster, MD, FACS, FACR, FAAO, Clinical Professor of Ophthalmology, Harvard Medical School; Consulting Staff, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary; Founder and President, Ocular Immunology and Uveitis Foundation, Massachusetts Eye Research and Surgery Institution
Contributor Information and Disclosures

Updated: Sep 25, 2008

Differential Diagnoses

Other Problems to Be Considered

Intermediate uveitis
Multifocal choroiditis
Multiple evanescent white dot syndrome
Reticulum cell sarcoma
Panuveitis

Workup

Laboratory Studies

  • Blood testing for HLA-A29 helps to support the diagnosis, but not all patients with birdshot retinochoroidopathy are HLA-A29 positive. One must note that false-negative results with HLA-A29 testing may occur, and repeat blood testing is warranted in situations where clinical suspicion is high.
  • Other blood testing is not diagnostically helpful for patients with suspected birdshot retinochoroidopathy. Fuerst and colleagues performed serologic testing of various markers of immune system activity and found elevated C4 levels; alpha-1-antitrypsin; C-reactive protein; rheumatoid factor; serum immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin A (IgA); properdin factor B; and C3 were in the reference range.5 However, their series of patients was small (ie, 9 patients).5
  • Testing for baseline renal function is necessary in those patients most likely to need cyclosporine therapy.
  • Purified protein derivative (PPD)

Imaging Studies

  • Fluorescein angiography
    • Early cream-colored lesions, which are active sometimes, may present as isofluorescence, and this occurs when the lesion is deep or when the retinal pigment epithelium (RPE) and the choriocapillaris are intact. If there is disruption to any one of them, the lesion will be fluorescent, especially in the late phase. Late focal depigmentation or an atrophic lesion presents as hypofluorescence in the early phase and as diffuse hyperfluorescence in the late phase.
    • Retinal vascular system and cystoid macular edema
      • Delayed in the filling time and prolongation of the arteriovenous transient phase 
      • Hyperfluorescence of the optic disc and the macula that form cystoid macular edema
  • Indocyanine green angiography
    • Indocyanine green angiography (ICG) provides the additional dimensions of the choroidal lesion analysis in birdshot retinochoroidopathy.
    • ICG reveals well-delineated hypofluorescence choroidal spots in the mid phase of the study. These hypofluorescent spots not only correspond to the location of the birdshot retinochoroidopathy lesions but also are far more numerous than those seen on either fluorescein angiography or clinically. These choroidal lesions assume a vasotropic distribution bordered by medium- to large-sized choroidal blood vessels.
  • Ultra-high resolution optical coherence tomography
    • Ultra-high resolution optical coherence tomography (OCT) showed photoreceptor atrophy in several areas of both eyes. RPE degeneration was present underneath the areas of photoreceptor involvement. The inner retinal layers were hard to delineate because of the anatomical disorganization.
    • Ultra-high resolution OCT imaging may help in understanding and following the progression of macular involvement in birdshot retinochoroidopathy.
  • Chest x-ray

Other Tests

  • Electrophysiologic testing may aid in determining the reason for complaints of problems with color perception or night vision. Both electro-oculograms (EOG) and electroretinograms (ERG) are affected. The presence of an abnormal electrophysiologic test may help distinguish it from other entities with similar funduscopic appearances. Currently, the use of serial ERGs as a tool to assist in monitoring birdshot retinochoroidopathy activity and response to therapy is being investigated.  
    • The ERG evolves into a negative pattern ERG, characterized by a decrease in b-wave amplitude, with no affect on a-wave amplitude. This occurs in diseases in which the retinal neural network function, corresponding to the b wave, is involved with progressive disease, but the photoreceptor function, represented by the a wave, initially is uninvolved.
    • In advanced birdshot retinochoroidopathy, both a-wave and b-wave amplitudes are decreased, suggesting dysfunction of all retinal layers, including the photoreceptors.
    • EOG testing also was decreased in patients, representing RPE dysfunction.
    • Pattern evoked cortical potential (PECP) showed reduced amplitude and delayed response.
    • Dark adaptation abnormalities suggested that the rod system was more affected than cones. However, the case series was small, and more supportive data are needed to confirm these findings.

Histologic Findings

Only two histopathology studies have been obtained on the eyes of patients affected by birdshot retinochoroidopathy.
 
Nussenblatt and coauthors described the histopathological findings of a single, phthisical eye enucleated from a patient with birdshot retinochoroidopathy who exhibited a positive in vitro lymphocyte proliferative response to retinal S-Ag.4 The histopathology revealed a mild lymphocytic response, whereas the retina was involved with a diffuse, chronic granulomatous inflammation.

Gaudio and coauthors described the histopathology of a blind, phthisical eye of a patient positive for the HLA-A29 gene and diagnosed with birdshot retinochoroidopathy.6 This study found aggregation of the lymphocytes with their foci in the deep choroid, with additional foci in the optic nerve head and along the retinal vasculature. These histopathological findings were noted to have a vasotropic distribution.

More on Retinopathy, Birdshot

Overview: Retinopathy, Birdshot
Differential Diagnoses & Workup: Retinopathy, Birdshot
Treatment & Medication: Retinopathy, Birdshot
Follow-up: Retinopathy, Birdshot
References
[ CLOSE WINDOW ]

References

  1. Ryan SJ, Maumenee AE. Birdshot retinochoroidopathy. Am J Ophthalmol. Jan 1980;89(1):31-45. [Medline].

  2. LeHoang P, Ozdemir N, Benhamou A, et al. HLA-A29.2 subtype associated with birdshot retinochoroidopathy. Am J Ophthalmol. Jan 15 1992;113(1):33-5. [Medline].

  3. Levinson RD, Rajalingam R, Park MS, et al. Human leukocyte antigen A29 subtypes associated with birdshot retinochoroidopathy. Am J Ophthalmol. Oct 2004;138(4):631-4. [Medline].

  4. Nussenblatt RB, Mittal KK, Ryan S, et al. Birdshot retinochoroidopathy associated with HLA-A29 antigen and immune responsiveness to retinal S-antigen. Am J Ophthalmol. Aug 1982;94(2):147-58. [Medline].

  5. Fuerst DJ, Tessler HH, Fishman GA, et al. Birdshot retinochoroidopathy. Arch Ophthalmol. Feb 1984;102(2):214-9. [Medline].

  6. Gaudio PA, Kaye DB, Crawford JB. Histopathology of birdshot retinochoroidopathy. Br J Ophthalmol. Dec 2002;86(12):1439-41. [Medline].

  7. Vitale AT, Rodriguez A, Foster CS. Low-dose cyclosporine therapy in the treatment of birdshot retinochoroidopathy. Ophthalmology. May 1994;101(5):822-31. [Medline].

  8. Kiss S, Ahmed M, Letko E, et al. Long-term follow-up of patients with birdshot retinochoroidopathy treated with corticosteroid-sparing systemic immunomodulatory therapy. Ophthalmology. Jun 2005;112(6):1066-71. [Medline].

  9. LeHoang P, Cassoux N, George F, et al. Intravenous immunoglobulin (IVIg) for the treatment of birdshot retinochoroidopathy. Ocul Immunol Inflamm. Mar 2000;8(1):49-57. [Medline].

  10. Bloch-Michel E, Frau E. Birdshot retinochoroidopathy and HLA-A29+ and HLA-A29- idiopathic retinal vasculitis: comparative study of 56 cases. Can J Ophthalmol. Dec 1991;26(7):361-6. [Medline].

  11. Brucker AJ, Deglin EA, Bene C, et al. Subretinal choroidal neovascularization in birdshot retinochoroidopathy. Am J Ophthalmol. Jan 15 1985;99(1):40-4. [Medline].

  12. Caballero-Presencia A, Diaz-Guia E, Lopez-Lopez JM. Acute anterior ischemic optic neuropathy in birdshot retinochoroidopathy. Ophthalmologica. 1988;196(2):87-91. [Medline].

  13. de Smet MD, Yamamoto JH, Mochizuki M, et al. Cellular immune responses of patients with uveitis to retinal antigens and their fragments. Am J Ophthalmol. Aug 15 1990;110(2):135-42. [Medline].

  14. Godel V, Baruch E, Lazar M. Late development of chorioretinal lesions in birdshot retinochoroidopathy. Ann Ophthalmol. Feb 1989;21(2):49-52. [Medline].

  15. Hirose T, Katsumi O, Pruett RC, et al. Retinal function in birdshot retinochoroidopathy. Acta Ophthalmol (Copenh). Jun 1991;69(3):327-37. [Medline].

  16. Kaplan HJ, Aaberg TM. Birdshot retinochoroidopathy. Am J Ophthalmol. Dec 1980;90(6):773-82. [Medline].

  17. Kiss S, Anzaar F, Stephen Foster C. Birdshot retinochoroidopathy. Int Ophthalmol Clin. Spring 2006;46(2):39-55. [Medline].

  18. Levinson RD, Gonzales CR. Birdshot retinochoroidopathy: immunopathogenesis, evaluation, and treatment. Ophthalmol Clin North Am. Sep 2002;15(3):343-50, vii. [Medline].

  19. Noble KG, Greenberg J. Appearance of birdshot retinochoroidopathy in a patient with myelodysplasia syndrome. Am J Ophthalmol. Jan 1998;125(1):108-9. [Medline].

  20. Oh KT, Christmas NJ, Folk JC. Birdshot retinochoroiditis: long term follow-up of a chronically progressive disease. Am J Ophthalmol. May 2002;133(5):622-9. [Medline].

  21. Rosenberg PR, Noble KG, Walsh JB, et al. Birdshot retinochoroidopathy. Ophthalmology. Mar 1984;91(3):304-6. [Medline].

  22. Soubrane G, Bokobza R, Coscas G. Late developing lesions in birdshot retinochoroidopathy. Am J Ophthalmol. Feb 15 1990;109(2):204-10. [Medline].

  23. Soubrane G, Coscas G, Binaghi M, et al. Birdshot retinochoroidopathy and subretinal new vessels. Br J Ophthalmol. Jul 1983;67(7):461-7. [Medline].

[ CLOSE WINDOW ]

Further Reading

[ CLOSE WINDOW ]

Keywords

birdshot retinopathy, birdshot retinochoroidopathy, BSRC, vitiliginous chorioretinitis

[ CLOSE WINDOW ]

Contributor Information and Disclosures

Author

C Michael Samson, MD, Associate Professor, Department of Ophthalmology, New York Medical College; Consulting Staff, Co-director of Uveitis Service, Faculty in Residency Training Program, Director of Uveitis Fellowship Training Program, Department of Ophthalmology, New York Eye and Ear Infirmary; Private Practice, Vitreous Retina Macula Consultants of New York
C Michael Samson, MD is a member of the following medical societies: American Academy of Ophthalmology, American Medical Association, American Uveitis Society, and Association for Research in Vision and Ophthalmology
Disclosure: Nothing to disclose.

Coauthor(s)

Amro Mohamed Mohamoud Ali, MB, ChB, Consulting Staff, New York Eye and Ear Infirmary
Amro Mohamed Mohamoud Ali, MB, ChB is a member of the following medical societies: American Academy of Ophthalmology
Disclosure: Nothing to disclose.

C Stephen Foster, MD, FACS, FACR, FAAO, Clinical Professor of Ophthalmology, Harvard Medical School; Consulting Staff, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary; Founder and President, Ocular Immunology and Uveitis Foundation, Massachusetts Eye Research and Surgery Institution
C Stephen Foster, MD, FACS, FACR, FAAO is a member of the following medical societies: Alpha Omega Alpha, American Academy of Ophthalmology, American Association of Immunologists, American College of Rheumatology, American College of Surgeons, American Federation for Clinical Research, American Medical Association, American Society for Microbiology, American Uveitis Society, Association for Research in Vision and Ophthalmology, Massachusetts Medical Society, Royal Society of Medicine, and Sigma Xi
Disclosure: Nothing to disclose.

Medical Editor

Russell P Jayne, MD, Consulting Vitreoretinal Surgeon, The Retina Center at Las Vegas
Russell P Jayne, MD is a member of the following medical societies: American Medical Association, American Society of Cataract and Refractive Surgery, and American Society of Retina Specialists
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Steve Charles, MD, Director of Charles Retina Institute; Clinical Professor, Department of Ophthalmology, University of Tennessee College of Medicine
Steve Charles, MD is a member of the following medical societies: American Academy of Ophthalmology, American Society of Retina Specialists, Club Jules Gonin, Macula Society, and Retina Society
Disclosure: Alcon Laboratories Consulting fee Consulting; OptiMedica Ownership interest Consulting

CME Editor

Lance L Brown, OD, MD, Ophthalmologist, Affiliated With Freeman Hospital and St John's Hospital, Regional Eye Center, Joplin, Missouri
Disclosure: Nothing to disclose.

Chief Editor

Hampton Roy Sr, MD, Associate Clinical Professor, Department of Ophthalmology, University of Arkansas for Medical Sciences
Hampton Roy Sr, MD is a member of the following medical societies: American Academy of Ophthalmology, American College of Surgeons, and Pan-American Association of Ophthalmology
Disclosure: Nothing to disclose.

 
 
HONcode

We subscribe to the
HONcode principles of the
Health On the Net Foundation

All material on this website is protected by copyright, Copyright© 1994- by Medscape.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.