Eye Signs of Systemic Disease: Case 3 Presumed Ocular Histoplasmosis Syndrome

By Leonid Skorin, Jr, DO
Volume 44 - Issue 1 - January 2004

Long-standing chorioretinal scarring in both eyes did not affect a 67-year-old woman’s vision. The scars were roundish, irregular, and yellowish white with interior pigmentation (A and B). This patient had presumed ocular histoplasmosis syndrome (POHS), a common disorder in regions such as the Mississippi, Ohio, and Missouri river valleys, where the fungus Histoplasma capsulatum is endemic. Inhaled spores of the culprit organism cause granulomas in the lungs, liver, spleen, and the choroid of the eye. Unless the macula is involved, the patient’s vision is unaffected. Typical findings in infected patients include:

  • Punched-out “histo” spots that can be seen throughout the retina (A and B).
  • Peripapillary—diffuse, circumferential choroidal—atrophy that extends beyond the disc margin (C, in a different patient).
  • Linear streaks of chorioretinal atrophy seen in the periphery.
  • Choroidal neovascularization, which may be characterized by serous detachment of the retina, subretinal hemorrhage, and hard lipid exudate. In most patients, the choroidal neovascularization occurs at the edge of an old healed chorioretinal scar.
  • Absence of vitritis or iritis.
  • Positive skin tests for Histoplasma. This is a common finding in most patients with POHS. Refer those with active lesions to an infectious disease specialist.
  • HLA markers B7, DR2, and DQ1, which may genetically predispose persons to POHS.
Macular involvement results in impaired vision. Laser treatment of macular lesions is ineffective; however, active lesions outside the macula may be treated with laser photocoagulation. Treatment of inactive lesions is not advised because it may stimulate subretinal neovascularization. Because this patient’s lesions were inactive, no therapy was warranted. Annual eye examinations were recommended.
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