Sir,In their interesting study, Hosseini et al[1] addressed the proportions of causes of various types of uveitis in patients referred to a tertiary center in northeastern Iran. They found that human immunodeficiency virus (HIV) uveitis was observed in only 2 (0.9%) patients. I presume that the actual proportion was underestimated. My presumption is based on the following relevant points.First, it is evident that HIV could affect any part of the body, including the eyes. Various ophthalmic manifestations of HIV infection have been identified, including uveitis,[2] which could be an early manifestation of HIV infection.[3]Second, to my knowledge, HIV infection is an important health hazard in Iran. Although no recent data are yet available on the exact HIV seroprevalence in Iran, the available data reveal that the overall HIV rates in Iran have alarmingly increased by 80% each year for the past decade.[4] This increase in HIV rate is expected to be associated with an increasing risk of various ocular manifestations, including uveitis.Third, due to low immunity, individuals infected with HIV are at an increased risk of various infectious agents, including bacteria, Mycobacterium tuberculosis (MT), parasites, viruses, and fungi, compared to immunocompetent individuals. There are protean ocular manifestations of HIV infection. Abdollahi et al found that of all orbital manifestations, MT, cytomegalovirus (CMV), toxoplasmosis, and herpes-related lesions were the predominant HIV-related ocular involvements in HIV-positive Iranian patients.[5] It could be possible that many infection-associated uveitis cases addressed in Hosseiniet al'sstudy,[1] notably CMV, MT, herpes, toxoplasmosis, and leishmaniasis, were concomitant clinical findings of underlying HIV infection. This would definitely cast some suspicions regarding the accuracy of the proportions of various etiologies of uveitis in Hosseiniet al's study.[1]Fourth, the exact diagnostic algorithm employed to discern HIV uveitis in the studied cohort was not obvious because Hosseini et al briefly mentioned in the methodology that serology confirmation for HIV was performed.[1] It is explicit that the diagnostic set of concurrent determination of HIV load in intraocular fluids and plasma, as well as blood CD4 count estimation, is crucial for the sound diagnosis of HIV uveitis. Hence, I presume that if that the diagnostic set was employed, the proportion of HIV uveitis might be altered in Hosseini et al's study.[1]