Monitoring of human cytomegalovirus (HCMV)-specific CD4+ T cell frequency by cytokine flow cytometry as a possible indicator for discontinuation of HCMV secondary prophylaxis in HAART-treated AIDS patients.
OBJECTIVE
Absolute CD4+ T cell count and human cytomegalovirus (HCMV)-specific CD4+ T cell frequency (as determined by cytokine flow cytometry, CFC) were compared for their ability to predict HCMV disease and safe discontinuation of HCMV secondary prophylaxis.


METHODS
Three groups of AIDS patients with previous nadir CD4+ T cell count <100/microl were studied. Group A included 48 HAART-treated patients with no HCMV disease. Group B included 11 HAART-treated patients with previous HCMV disease who discontinued HCMV prophylaxis. Group C included 23 HAART-treated (n = 16) or -naive (n = 7) patients with previous HCMV disease either continuing or starting HCMV prophylaxis. Patients underwent follow-up for detection of HCMV viremia or disease (groups A and B) and for discontinuation of HCMV secondary prophylaxis on the basis of either HCMV-specific or absolute CD4+ T cell count (group C).


RESULTS
During follow-up, while some patients showed a stable HCMV-specific CD4+ T cell response, others had a fluctuating response (unstable responders) or showed no response at all. In detail, 13/48 group A patients were either HCMV non-responders or unstable responders and 2 of them developed HCMV viremia; 3/11 group B patients were unstable responders, none developing either HCMV viremia or disease; finally, 9 group C patients discontinued HCMV prophylaxis based on absolute CD4+ T cell count > 150 cells/microl, but in 2 of them lacking HCMV-specific response HCMV retinitis relapsed. None of the seven group C patients discontinuing HCMV prophylaxis on the basis of CFC showed HCMV disease relapse.


CONCLUSIONS
CFC may support absolute CD4+ T cell count for both guiding HCMV prophylaxis discontinuation and better monitoring HCMV infection in AIDS patients with no previous HCMV disease or having discontinued HCMV prophylaxis.
Lilleri
Daniele
D
Servizio di Virologia, IRCCS Policlinico San Matteo, Via Taramelli 5, 27100 Pavia, Italy.
Piccinini
Giampiero
G
Genini
Emilia
E
Comolli
Giuditta
G
Chiesa
Antonella
A
Tordato
Federica
F
Sotgiu
Giovanni
G
Parisi
Aldo
A
Baldanti
Fausto
F
Revello
Maria Grazia
MG
Gerna
Giuseppe
G
D017088:AIDS-Related Opportunistic Infections / Q000188:drug therapy / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D000163:Acquired Immunodeficiency Syndrome / Q000150:complications / Q000188:drug therapy*; D000293:Adolescent; D000328:Adult; D000368:Aged; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D002648:Child; D003587:Cytomegalovirus / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000188:drug therapy / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014766:Viremia