CD4 and AIDS dementia complex: Thus, whereas the increases in blood and CSF levels of neopterin were of similar magnitude in the neuroasymptomatics (for example, mean CSF and blood levels of patients with <50 CD4+ cells/μL were 26.2 and 28.2 nmol/L, respectively), the increase in blood neopterin in the ADC patients was notably less marked than in the CSF.