Tuberculosis (TB) in the leading cause of death for people with HIV, so an easy test is essential in fighting preventable deaths. It turns out that such a test already exists — but it’s rarely used in the countries that could benefit from it most, the New York Times reported.
“There is a $3.50 rapid test that works on urine, for crying out loud, and the fact that it’s not being utilized is just ridiculous,” Sharonann Lynch, a policy adviser at Doctors Without Borders, told the New York Times.
The urine test that Lynch is referring to has been recommended by the World Health Organization (WHO) since 2015. It detects lipoarabinomannan, which is found in the TB bacterium.
This is significant because most TB tests need to use sputum, which is a mix of saliva and mucus that gets coughed up from the respiratory tract, and it can be hard for someone with HIV to produce, according to the New York Times.
So why aren’t countries using this easy urine test? Well, for starters, it’s not perfect.
“It’s a test with suboptimal accuracy,” Christopher Gilpin, senior scientist at the WHO’s Global TB Program, told the New York Times. “This is probably part of the limited uptake.”
The WHO recommends the test only for people who are HIV-positive and critically ill, with less than 100 CD4 cells per cubic millimeter of blood.
CD4 cells are white blood cells that help the immune system fight infections. A healthy count ranges between 500 and 1,600 cells per cubic millimeter of blood, according to HIV.gov.
For people living with these conditions, the test accurately diagnoses TB in 56% of patients.
Still, critics argue the benefits are there.
“It’s not a perfect test, but there’s literally zero harm in doing it and it has saved a lot of lives,” Erica Lessem, deputy executive director for programs at Treatment Action Group, told the New York Times.
The WHO’s recommendation for the test is too restricted, Lynch said, and she pointed out that organizations follow WHO recommendations closely.
The WHO’s proposal is carefully worded because the test is less accurate for those with higher CD4 levels and they worry it would be misused, according to Gilpin.
“The WHO is giving really mixed signals to countries and to suppliers and manufacturers, because they’re basically saying on the one hand we’re asking for this point-of-care test, we want to do more to stop mortality — and on the other hand, actually we think that even though we have this tool, it’s not worth rolling out,” Lessem said.
What’s more is that clinics in areas with few resources often do not have the equipment needed to test CD4 levels.