【摘要】 采用高效抗逆转录病毒疗法(HAART)后，由于免疫功能恢复和机会性感染的减少，极大地改变了艾滋病毒(HIV)感染者眼部疾病的病程及病史。然而，即使在HAART时代，眼部并发症仍然是艾滋病的临床特征之一，在发展中国家中尤其如此，而绝大多数HIV阳性病患者生活在发展中国家或地区。由于缺乏检验设备和经验、卫生条件差、微生物环境不同及缺乏有效的治疗，生活在发展中国家和地区的HIV感染者眼部并发症的特征与发达地区的艾滋病患者大不相同。因此，治疗发展中国家和地区HIV感染者的眼部并发症，具有更大的挑战性。此外，成人和儿童艾滋病患者眼部并发症也是不同的。与此同时，HAART的副作用也给眼部并发症带来了新的危险因素。所以，相关的研究应给予更多的关注。
【关键词】 艾滋病毒；眼部并发症；视网膜病变；肿瘤；机会性感染；高效抗逆转录病毒疗法
INTRODUCTION
Human immunodeficiency virus (HIV) continues to be one of the most devastating evils that pose great threat to public health worldwide, especially in the developing countries, which amounts to more than 95% of global HIV infections. Being the most severe infected region, SubSaharan Africa accounts for more than two thirds of HIV infections and three quarters of all AIDS deaths in 2007. The HIV epidemic in South and Southeast Asia is among the second largest in the world, India making up half of the HIVinfected population in Asia (Figure 1).
Complications commonly involve the eyes in HIVinfected persons. Autopsy revealed that up to 95% of AIDS patients have some form of ocular abnormalities[1]. Ocular lesions are varied and affect almost all parts of the eye. In the early stages of HIV infection, ophthalmic manifestations may be asymptomatic, thus hampering prompt medical attention and, ultimately, leading to a variety of tissuedestructive conditions, including visual impairment and even blindness. Since HIV has been isolated from retina, it is believed that ocular complication results either from a general decrease of host immunity or, more likely, direct ocular infection by HIV through the bloodaqueous barrier and/or bloodretinal barrier.
Ocular complication of HIV/AIDS differs from region to region. Most of the reports on ophthalmic manifestations of HIV infection come from developed countries, especially in the preHAART era. However, in recent years more and more cases and reports on ocular complication of HIV infection are being documented in developing countries, revealing an increasing attention and concern of the ocular status of HIV patients in these regions in which most of HIVpositive population live nowadays.
RISK PREDICTOR OF OCULAR COMPLICATIONS IN HIVPOSITIVE PATIENTS
The number of CD4 T cells which are the primary targets and reservoirs of HIV infection, serves as the key marker of the hosts immune competence to respond to opportunistic pathogens. Its been many years that CD4 T lymphocytes counts has been proved a reliable and important predictor of the risk for developing and indicator for managing ocular complications of HIV infection. Different ocular complica tions may develop at different CD4 threshold. However, CD4 threshold may not always be the absolute criterion for predicting ocular complications since reconstituted CD4+ lymphocytes due to HAART may fail to provide protective immunity. Some reports revealed that HIVpositive patients with CD4+ counts higher than 200 cells/μL developed cytomegalovirus retinitis. Table 1a Ophthalmic findings with HIV infection in some countries which have conducted surveys in the preHAART era（略）Table 1b Ophthalmic findings with HIV infection in some countries which have conducted surveys in the preHAART era（略）
Also, the incidence of ocular disorders correlates with the WHO clinical stage of HIV/AIDS. Stage 4 patients suffer the great chance to be affected. The prevalence of ocular manifestations in patients with stage 3 is greater than those with stages 1 and 2[2]. Some studies suggest that homosexuality may place HIV patients at higher risk for ocular problems[3].
HIGHLY ACTIVE ANTIRETROVIRAL THERAPY
Thus far, AIDS is not yet curable, and there is no effective vaccine for prevention. However, the introduction of HAART over the past decade has resulted in a dramatic reduction in the morbidity and mortality and an improved quality of life of HIV/AIDS patients. As a consequence of HAART, the pattern and nature history of ocular problems of HIV infection has significantly altered[4]. HAART usually consists of three different kinds of antiretroviral drugs, nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors and protease inhibitors. The use of HAART has resulted in the ability of the host to regain immunity and suppress viral loads.Table 2a Ophthalmic findings with HIV infection in some countries which have conducted surveys in the HAART era（略）Table 2b Ophthalmic findings with HIV infection in some countries which have conducted surveys in the HAART era（略）
Some reports associated with ocular observation in HIVpositive patients in different countries both in preHAART and HAART era have been summarized (Table 1 and 2). Although different reports examined using different protocol, there is obviously a profound changing face of ophthalmic problems of HIV infection due to the availability of HAART. The incidence of ocular complication of HIVpositive patients has decreased from as high as 80% before the HAART era to less than 40% in the HAART era in general. Cytomegalovirus (CMV) retinitis and microvasculopathy continue to be the major types of ocular complications in HIV patients in the HAART era even with a significant declining incidence. However, we should keep in mind that despite the widespread use of HAART in developed countries, in many parts of the developing world, up to 80% of people infected with HIV who are in clinical need of treatment do not yet have access to antiretroviral drugs. Besides the cost of HAART, some factors such as restrictive licensing policies hamper the development and use of HAART in developing regions. Therefore, the ophthalmic manifestation of HIV infection in developing countries, especially in SubSaharan Africa, is characterized itself from that in developed countries by the higher incidence and more prevalence of opportunistic infections in the HAART era. Many factors, such as lack of effective antiviral therapies,lack of test facilities and experience, poor hygiene conditions, different microbiological environment, patients nutritional status, may contribute to this distinction. Table 3 Common ocular opportunistic pathogens and sites of infection in HIV/AIDS patients（略）
CYTOMEGALOVIRUS RETINITIS AND OTHER OPPORTUNISTIC INFECTIONS
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