Objective: To validate the technique of HIV-1 culture from whole blood
for the quantitation of viral load in infected children. Patients: Fo
rty-three HIV-1-infected children were followed in two paediatric cent
res. Methods: Quantitative HIV-1 cultures from unfractionated whole bl
ood using an end-point dilution technique were compared with simultane
ous quantitative cultures of peripheral blood mononuclear cells (PBMC)
and plasma. Results: Good sensitivity (93%) of the methods used was c
onfirmed. A close correlation (r = 0.80) was observed between HIV-1 ti
tres measured directly from whole blood and those expected from PBMC a
nd plasma titres. The mean whole blood viral load was higher in patien
ts with more severe signs of disease, but the difference did not reach
statistical significance. The whole blood viral titres measured seque
ntially at monthly intervals remained within one dilution of each othe
r in 16 of the 22 patients studied. Conclusion: In this study, the qua
ntitation of HIV-1 in unfractionated blood allowed for a reliable and
sensitive measurement of the whole blood viral load in infected childr
en.