This report documents the feasibility of training primary care AIDS clinicians to diagnose and treat CMV retinitis in a resource-limited setting. CMV retinitis screening is now carried out in four regions in Myanmar, and at the beginning of 2010, covered the majority of patients treated with ART in the country.
The high prevalence of CMV retinitis that we identified and the severity of the consequences of CMV retinitis demonstrate the importance of routine CMV retinitis screening in this setting. CMV retinitis was diagnosed in 211 out of 891 (24%) new patients screened in the Yangon Division, and these patients required urgent treatment to prevent blindness. Blindness has catastrophic consequences for these patients who are at a relatively young age, as well as for their families.
We are aware of the potential risk of causing an attack of acute angle-closure glaucoma and blindness by dilation of the pupil in a setting where back-up ophthalmic care may not be available. However, we consider that overall, the balance of risks finds in favour of using this approach: while the risk of angle closure is low (no episodes thus far), the risk of blindness from undetected and untreated CMV retinitis in this population is high.
Our experience in Myanmar demonstrates the feasibility of training AIDS clinicians to diagnose and treat CMV retinitis. Even with a limited background in ophthalmology, CMV retinitis is not difficult to diagnose. At the end of the four-day workshop, most AIDS clinicians were able to begin screening patients with the indirect ophthalmoscope, and after three to six months of practice, most were highly proficient. By one year, AIDS clinicians regarded CMV retinitis as the easiest diagnosis to establish among major opportunistic infections whereas previously, it was regarded as the most difficult. However, diagnosis of the ophthalmologic complications of CMV retinitis, retinal detachment and immune recovery uveitis (IRU) remains a challenge, as does distinguishing active from inactive retinitis in patients with IRU.
This report comes from a routine programme and as such there are several potential limitations to note. It is possible that some clinical events were missed due to missed appointments or unrecorded events. We are confident that the recording of important clinical events is reliable given that a strong emphasis is placed on data collection to support cohort monitoring in this programme. As is the case for HIV/AIDS care generally in many settings in the developing world, this programme receives support from a non-governmental organization that provides additional resources that may limit the potential for replication in settings where such additional resources are lacking. However, we consider that with adequate commitment, training and support, the approach could be extended to other, similar settings.
The set-up cost for a CMV retinitis screening programme is modest: the only equipment needed is a portable battery-operated indirect ophthalmoscope with a 28 diopter lens. Dilating drops are inexpensive. Only one clinician needs to be trained per centre, and that clinician carries out all the screening and patient management so as to remain highly practiced and skilled. Screening of one patient (two eyes) takes approximately three minutes, and one intraocular injection takes 15-20 minutes. In Myanmar, diagnostic screening and treatment has usually been managed within a single half-day clinic each week.
Treatment, however, remains problematic. As we found, treatment with intraocular injection of ganciclovir can safely be implemented at the primary care level by non-ophthalmologists, and we strongly support this treatment intervention in the absence of alternatives. Ganciclovir injection is certainly affordable [1
], costing less than US$1.00 per weekly injection, and intraocular injection of ganciclovir is highly effective at controlling retinitis in the injected eye. However, intraocular injection does not treat or prevent against potentially fatal extra-ocular CMV disease, nor does it prevent the development of disease in the contralateral eye. It requires weekly clinic visits that may be cumbersome, and patients must endure repeated injections into the eye.
In contrast, patients in developed countries are treated for the same problem with a simple pill. Systemic treatment of CMV retinitis with oral valganciclovir is the standard of care in western countries [14
]. Reduction in mortality has been observed with systemic treatment of CMV retinitis [16
], even in patients failing ART therapy [17
]. Although we are not able to provide outcome data in support for this standard of care in this report, we consider that that available evidence supports the use of intraocular injection as a valuable step in providing high-quality care to patients with CMV retinitis. However, intraocular injection alone is not adequate. Systemic treatment with oral valganciclovir [18
] should be made affordable and widely available.
Future research should more adequately document the prevalence of CMV in resource-limited settings, and better evaluate treatment outcomes for patients treated with valganciclovir and intraocular ganciclovir, including through randomized trials.