eMedicine Specialties > Ophthalmology > Ophthalmology for the General Practitioner
Ocular Manifestations of HIV: Differential Diagnoses & Workup
Updated: Oct 1, 2009
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
Workup
Laboratory Studies
- Herpes simplex keratitis
- A diagnosis of HSV is primarily clinical, and the use of fluorescein and rose bengal dyes will highlight the characteristic corneal dendrites with terminal bulbs.
- Laboratory studies, including virus culture, direct fluorescent antibody tests for HSV antigens, and PCR techniques for HSV DNA, can help to confirm the diagnosis.
- Herpes zoster ophthalmicus
- Diagnosis of HZO is primarily by history and examination. However, baseline complete blood count, electrolytes, glucose, blood urea nitrogen, and creatine may be necessary prior to starting antiviral drugs.
- When a clear diagnosis cannot be made, a noncontrast CT scan should be considered to evaluate for other causes of new-onset headache.
- Fungal keratitis
- Diagnosis of fungal keratitis includes a detailed history and complete ophthalmologic examination. History should include contact lenses use, lens-care regimen, previous corneal disease, and topical or systemic steroid use.
- A thorough slit lamp examination is important. Deep corneal scrapings or even corneal biopsy for Giemsa, periodic acid-Schiff, or Gomori methenamine-silver staining with culture and sensitivity to define treatment, particularly with persistent ulcer may be indicated.
- Microsporidia
- History and detailed ophthalmic examination should be performed to diagnose Microsporidia.
- Spores, sporoblasts, meronts, and sporonts can be identified in conjunctival or corneal scrapings from affected patients. The spores are Gram-positive and acid-fast by staining.
- Microsporidia is very difficult to culture, but it is seen readily within corneal or conjunctival epithelial cells with the use of Masson trichrome or Giemsa staining. The diagnosis may be aided by the use of electron microscopy and confocal microscopy in vivo.
- HIV retinopathy
- A history and complete ophthalmologic examination with dilated funduscopic examination should be performed for diagnosis of HIV retinopathy.
- Significant retinal nerve fiber layer loss occurs in HIV patients without CMV retinitis with low CD4 counts. Third-generation OCT may be useful in establishing a diagnosis of early subclinical HIV-associated visual functional loss.
- CMV retinitis
- History and complete ophthalmologic examination with dilated funduscopic examination should be performed for diagnosis of CMV retinitis.
- Consultation to primary care physician should be obtained for systemic CMV infection workup, checking for urine and serum CMV titers.
- Acute retinal necrosis
- Perform a detailed history and a complete ophthalmologic examination with dilated funduscopic examination for diagnosis of ARN.
- Check for HSV-1, HSV-2, and CMV IgG and IgM titers.
- Progressive outer retinal necrosis
- Workup of PORN is similar to ARN, except that the serology focuses on HZV IgG and IgM titers.
- See ARN for details.
- Syphilis
- The VDRL becomes positive 1-3 weeks after the appearance of the chancre.
- Fluorescent treponemal antibody absorption (FTA-ABS) test or microhemagglutination Treponema pallidum (MHA-TP) is highly sensitive and specific in all stages of syphilis. Once reactive, these tests do not reverse to normal, and they are not helpful in assessing the patient’s response to treatment.
- Lumbar puncture (LP) may be performed if the FTA-ABS test is positive combined with neurologic or neuro-ophthalmologic signs, papillitis, active chorioretinitis, or uveitis.
- Diagnoses of ocular syphilis should include obtaining a specific treponemal-antibody assay (FTA-ABS or MHA-TP) and nonspecific treponemal-antibody assay (Venereal Disease Research Laboratory [VDRL] test or rapid plasma reagin [RPR]). VDRL or RPR correlates with disease activity, and it is useful in monitoring response to treatment. It also is used for screening, but it may show a false-negative result in early primary, latent, or late syphilis. It is not as specific as FTA-ABS or MHA-TP.
- Tuberculosis
- Perform a detailed history and physical examination, attempting to rule out other causes of granulomatous disease, such as sarcoidosis, syphilis, leprosy, and brucellosis.
- Chest radiograph
- Perform a purified protein derivative (PPD) skin test; a reaction induration of more than 5 mm is considered positive in persons in close contact to patients with infectious tuberculosis, HIV-positive patients, and persons with positive chest x-ray of fibrotic lesions. A PPD reaction induration of more than 10 mm is considered positive for persons with medical risk factors for reactivation of latent tuberculosis; foreign-born individuals from areas with high tuberculosis prevalence, low-income populations, including blacks, Hispanics, and Native Americans; intravenous drug users; and nursing home residents. A PPD reaction induration of more than 15 mm is considered positive in individuals with no particular risk factor for tuberculosis.
- Culture for positive growth of M tuberculosis is needed to confirm the diagnosis of tuberculosis.
- Pneumocystic carinii
- Perform a detailed history for P carinii pneumonia and use of aerosolized pentamidine.
- Obtain induced sputum or bronchoalveolar lavage (BAL) for histopathologic evaluation.
- Complete an ophthalmologic examination.
- Request a medical consultation.
- Toxoplasma retinochoroiditis
- In the workup, consider syphilis, tuberculosis, and toxocariasis as differential diagnoses.
- Perform a detailed history and ophthalmologic examination. Serologic detection of antibodies to T gondii is important. Current available testing assays include the indirect hemagglutination assay (IHA) and the immunofluorescent antibody (IFA) test. This test measures both the IgG and IgM antibodies to T gondii. Request that the laboratory perform a 1:1 dilution, as only a positive result is required. Some less commonly used tests include the Sabin-Feldman dye and the enzyme-linked immunosorbent assay (ELISA) tests. Polymerase chain reaction (PCR) and cytologic demonstration of the organism in vitreous samples could be useful in some cases. Diagnosis of ocular toxoplasmosis requires the demonstration of a characteristic retinochoroiditic lesion and a positive serology at any titer.
- Fluorescein angiogram may be helpful when a choroidal neovascular membrane is suspected.
- Histoplasma chorioretinitis
- In the workup, consider the following differential diagnoses: toxoplasmosis and multifocal choroiditis with panuveitis.
- Perform a detailed history and complete ophthalmologic examination, including dilated funduscopic examination. Inquiring about possible time spent in the Ohio-Mississippi River Valley area is important. Also possible exposure to fowl should be inquired.
- Amsler grid should be used to assess central visual field for each eye.
- Fluorescein angiography may be used to detect a CNVM.
- Perform a detailed history and ophthalmologic examination for diagnosis of cryptococcal chorioretinitis. Diagnosis of cryptococcal chorioretinitis mostly is based on the clinical findings. A diagnostic vitreous tap may be performed, and the samples are examined by direct smear using India ink and cultured on Sabouraud agar at 37°C. Organism growth often takes place within 24-48 hours, producing mucoid, cream, or pink colonies.
- Evaluation of neuro-ophthalmologic manifestations in HIV typically includes MRI followed by a LP to determine cerebrospinal cell count, cytologic studies, culture, and antibody and antigen testing.
Imaging Studies
- Computer tomography of the head may be useful for patients with toxoplasmosis and cryptococcus.
More on Ocular Manifestations of HIV |
| Overview: Ocular Manifestations of HIV |
Differential Diagnoses & Workup: Ocular Manifestations of HIV |
| Treatment & Medication: Ocular Manifestations of HIV |
| Follow-up: Ocular Manifestations of HIV |
| References |
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Further Reading
Keywords
human immunodeficiency virus, HIV positive, HIV-associated eye disorders, HIV-associated ocular infections, AIDS, acquired immunodeficiency syndrome, Kaposi sarcoma, lymphoma, tuberculosis, pneumocystosis, toxoplasmosis, retinal microvasculopathy, conjunctival microvasculopathy, cytomegalovirus retinitis, CMV retinitis, varicella-zoster virus retinitis, VZV retinitis, mycobacterium avium complex infection, cryptococcosis, microsporidiosis, HIV encephalopathy, progressive multifocal leukoencephalopathy
Differential Diagnoses & Workup: Ocular Manifestations of HIV