Grey nails help predict need to start anti-HIV therapy in Malawians

Grey nails accurately predict if asymptomatic HIV-positive Malawians have a low CD4 cell count and need to commence antiretroviral therapy, according to a study published in the June edition of AIDS. The investigators believe that monitoring patients for nail discolouration could provide a useful tool for clinicians working in southern Africa who do not have access to CD4 cell count testing.

Since 2004, antiretroviral therapy has been freely available in Malawi who have a CD4 cell count below 200 cells/mm³ or who have AIDS. However, resources are not available for routine CD4 cell count testing in Malawi, and many patients starting antiretroviral therapy because they have progressed to AIDS are often in such poor health that they do not have an opportunity to benefit from HIV treatment.

There is therefore an urgent need for low cost tests to indicate advanced immune suppression in patients who remain free of the symptoms of HIV infection. Grey nails have been frequently observed in African HIV-positive patients who are not taking antiretroviral therapy, but this symptom has not previously been linked with any particular stage of HIV infection. Therefore, investigators from Malawi and the UK looked at the relationship between grey nails and CD4 cell count to see if this symptom could identify patients who would benefit from starting HIV treatment.

Their study included 222 patients receiving care at the Queen Elizabeth Central Hospital in Malawi. The patients were tested for HIV and had their CD4 cell count measured. Photographs were taken of their nails and were shown to three independent assessors who were blinded to the patients’ HIV status and CD4 cell count. The assessors were asked to grade the nails as grey, distal banded, or pink.

The patients had a median age of 34 years, 60% were male and 72% were HIV-positive. A similar number of patients were identified by the three assessors as having either grey or distal banded nails (p < 0.0001). Compared to pink nails, grey or distal banded nails, were strongly associated with a CD4 cell count below 200 cells/mm³ (p = 0.0001 for assessors one and two and p = 0.012 for assessor three). Four HIV-negative patients, however, were identified as having grey or banded nails by all three assessors.

The predictive value of grey or distal banded nails was 92% for a CD4 cell count below 350 cells/mm³ and 82% for a CD4 cell count below 200 cells/mm³.

Of the 53 HIV-positive patients with grey or distal banded nails, 21 had no severe symptoms of HIV infection, however 16 (76%) of these had a CD4 cell count below 200 cells/mm³.

“For clinicians working in sub-Saharan Africa without access to CD4 cell count testing, grey or distal banded nails represent an additional staging sign to help identify a subgroup of patients likely to benefit from antiretroviral therapy”, conclude the investigators.