Nevertheless, the inability of LAM testing to improve the diagnostic yield of a single sputum-based Xpert MTB/RIF, irrespective of declining CD4 cell count, is consistent with the findings of Lawn et al. and reflect the superior sensitivity of sputum-based Xpert MTB/RIF for the diagnosis of pulmonary TB [11, 36, 37]. This evidence concerns the gene CD4 and pulmonary tuberculosis.