If you are unable to obtain viral load or resistance testing then you must rely on other indicators of poential drug resistance. A falling CD4 cell count (or absolute lymphocyte count), weight loss, reduced appetite, new rashes or opportunistic conditions all support the loss of drug activity. Certainly, any of these in a patient with a history of suboptimal adherence to mediction makes resistance even more likely.
When resistance is supected then the patient and clinician must enter into a frank conversation regarding next steps. If the patient can commit to taking the medication as prescribed, a new so called 'second line' regimen should be started. This regimen should ideally contain drugs to which the virus is unlikely to be resistant.
Some basic understanding of cross-resistance of HIV medications is needed. In addiiton, the choice of second line drugs will be dictated by what is available in your country.
For those starting on d4T+3TC+nevirapine the next logical choice may be tenofovir+3TC (or FTC)+a protease inhibitor. Alternatively, ddI+AZT+a protease inhibitor may also be an option in such a cirucmstance.
A key is getting patients to take their medications. Recruiting a friend or family member (with the patient's permission) to help may be a start. In some places clinic staff visit patients to check on adherence and help fill pill boxes that are labeled by day. Regular office visits can also help. Much of this, of course, will depend on the culture and resources of your locale. Trying to get people o understand the benefits of the medications and dispelling negative myths around HIV drugs also will be of great help.
DW
