Some studies indicate that associated factors with failing to culture convert and unfavorable treatment outcome are older age, being male, unemployment, prisoner, alcoholism, baseline AFB smear positive, lung cavitation at baseline chest X-ray, resistance to ofloxacin and streptomycin, history of previous TB treatment and poor outcome of previous anti-tuberculosis treatment, smoker, drug user, HIV co-infection, lower body mass index and lower CD4 count [9, 11, 13–16]. The gene discussed is CD4; the disease is tuberculosis.