Recently, I took another test and they reported that my viral load went down from 172,000 to 91,000. But my log10 hiv rnn went from 5.36 to 4.962. Does that mean my cd4 count is going down as well? They think the reason that my viral load was high back in april was because i had the flu in jan.

Those values are actually reporting the same thing. A viral load of 172,000 is the same as a log copy number of 5.36. Although those two viral load values appear like they are significantly different, they really are not. We usually look for changes of 3 times (3 fold) or more or > 0.3 log to indicate a significant change in viral load. You did not provide any information about CD4 counts or CD4 percentages, so I could not comment about any significant changes there.