Change in T-lymphocyte count after initiation of highly active antiretroviral therapy in HIV-infected patients with history of Mycobacterium avium complex infection.
OBJECTIVE
To compare changes in CD4+, CD8+ and total lymphocyte counts after initiation of highly active antiretroviral therapy (HAART) between HIV-infected patients with and without a recent history of Mycobacterium avium complex (MAC) infection.


METHODS
Matched exposed-non-exposed retrospective cohort study.


RESULTS
Fifty-one patients with a recent history of MAC infection (MAC+) started a combination of at least three antiretroviral drugs. They were individually matched to 145 patients without any history of MAC infection (MAC-) according to CD4+ T-cell count (+/- 30 cells/mm3), previous experience of antiretroviral treatment, AIDS clinical stage at the time of HAART initiation (baseline), age (+/- 10 years) and gender. MAC+ and MAC- patients presented comparable median levels of total lymphocytes (488 vs 688/mm3, P=0.09), CD4+ (11 vs 16/mm3, P=0.15), CD8+ count (359 vs 386/mm3, P=0.39) and plasma HIV RNA (5.3 vs 5.1 log10 copies/ml, P=0.22) at baseline. After 6 months on HAART, the median increase of CD4+ T-cell count was 28 cells/mm3 (interquartile range [IQR]: 1-63) in MAC+ and 72 cells/mm3 (IQR: 34-120) in MAC- patients (P<0.0001), whereas the percentage of CD4+ T cells was not significantly different between the two groups (P=0.13). Comparable differences were observed for total lymphocytes and CD8+ T cells (P<0.001). The 6 months decline of plasma HIV RNA was not significantly different according to MAC exposure (-1.6 in MAC+ vs -1.8 log10 copies/ml in MAC- patients, P=0.65). Results were confirmed after adjustment for other characteristics than the matching variables and after taking into account potential informative bias due to unbalanced number of deaths between the two groups.


CONCLUSIONS
MAC infection at the time of HAART initiation is an important deleterious factor for immune reconstitution. A better understanding of the underlying mechanism and an evaluation of additional treatment strategies are necessary to help immune restoration in such circumstances.
Lazaro
Estibaliz
E
Department of Internal Medicine and Infectious Diseases, Bordeaux University Hospital, Bordeaux, France.
Coureau
Gaelle
G
Guedj
Jérémie
J
Blanco
Patrick
P
Pellegrin
Isabelle
I
Commenges
Daniel
D
Dabis
François
F
Moreau
Jean-François
JF
Pellegrin
Jean-Luc
JL
Thiébaut
Rodolphe
R
D017088:AIDS-Related Opportunistic Infections / Q000276:immunology / Q000382:microbiology; D000328:Adult; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D016516:CD4-CD8 Ratio; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy* / Q000276:immunology*; D006801:Humans; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D015269:Mycobacterium avium Complex; D015270:Mycobacterium avium-intracellulare Infection / Q000150:complications* / Q000276:immunology* / Q000382:microbiology