The audience’s response to all the talk about improving smear microscopy was mixed. Some felt that the combination of these approaches could achieve an impact similar to having a new more sensitive diagnostic test:
“I think by combining some of these ideas, that you know are very exciting, by collaborating we can push things forward to make it much easier for patients to get a diagnosis,” said Dr Fennally.
Others were guided by pragmatism. “I really think it’s unlikely that there are going to be new diagnostic tests that are a hundred percent sensitive, a hundred percent specific and we need to be thinking about combining tests in a way that is going to be intelligent and will supplement each other,” said one audience member.
“We must try and get what diagnostics exist, out to improve the diagnosis of tuberculosis in whatever part of the world it is required. The only difficulty is that the systems required to operationalise some of these diagnostics - the capacity is not there at the moment, and it is unlikely to be a short process in building that capacity,” said Andy Ramsay. ”There’s likely to be a delay, whichever diagnostic we choose. So, I think a combination of approaches is required here, to make sure that every step of that process, we’re doing the best that we can.”
But others had a darker take on the subject:
“It’s not acceptable to say, “well we just have to tweak the smears” so that we can try to make the diagnosis for TB in the rest of the world when we know it’s just not acceptable. We need to demand more”, said Dr Carol Dukes Hamilton of Duke University.
“Let’s remember that a positive smear is very good, but it is delayed diagnosis,” said another member of the audience. “The future should be tests where we can pick patients within the week of infection, when you don’t expect them to be smear-positive.”
Other items in this series
TB diagnosis special report: why smear microscopy needs to be improved
Background on smear microscopy in TB diagnosis
TB diagnosis: Reducing the number of smears and clinic visits needed
TB diagnosis: Improving the yield with fluorescence microscopy
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