Current issues in the biology of AIDS-related lymphoma

Circulating mediators of inflammation and immune activation in AIDS-related non-hodgkin lymphoma

BACKGROUND

Non-Hodgkin lymphoma (NHL) is the most common AIDS-related malignancy in developed countries. An elevated risk of developing NHL persists among HIV-infected individuals in comparison to the general population despite the advent of effective antiretroviral therapy. The mechanisms underlying the development of AIDS-related NHL (A-NHL) are not fully understood, but likely involve persistent B-cell activation and inflammation.

METHODS

This was a nested case-control study within the ongoing prospective Multicenter AIDS Cohort Study (MACS). Cases included 47 HIV-positive male subjects diagnosed with high-grade B-cell NHL. Controls were matched to each case from among participating HIV-positive males who did not develop any malignancy. Matching criteria included time HIV+ or since AIDS diagnosis, age, race and CD4+ cell count. Sera were tested for 161 serum biomarkers using multiplexed bead-based immunoassays.

RESULTS

A subset of 17 biomarkers, including cytokines, chemokines, acute phase proteins, tissue remodeling agents and bone metabolic mediators was identified to be significantly altered in A-NHL cases in comparison to controls. Many of the biomarkers included in this subset were positively correlated with HIV viral load. A pathway analysis of our results revealed an extensive network of interactions between current and previously identified biomarkers.

CONCLUSIONS

These findings support the current hypothesis that A-NHL develops in the context of persistent immune stimulation and inflammation. Further analysis of the biomarkers identified in this report should enhance our ability to diagnose, monitor and treat this disease.

High proportion of T-cell systemic non-Hodgkin lymphoma in HIV-infected patients in Lima, Peru

OBJECTIVE

Few reports have described the clinical and pathologic characteristics of HIV-related systemic non-Hodgkin lymphoma (sNHL) in developing countries. We aimed to determine these characteristics from a national HIV reference center in Peru and to evaluate factors associated with survival.

METHODS

A retrospective/prospective study of patients with HIV-related sNHL from the Guillermo Almenara General Hospital in Lima, Peru between 1993 and 2004. Clinical characteristics at diagnosis included age, gender, risk behavior, previous AIDS diagnosis, opportunistic diseases, previous highly active antiretroviral therapy, Karnofsky score, origin, clinical stage and B-cell symptoms of sNHL, and CD4 cell count. Cases of sNHL were classified according to the criteria of the World Health Organization.

RESULTS

Thirty-three cases were identified (26 male, age range: 38 +/- 10 years). Ten patients (30%) had a prior history of AIDS, 14 (42%) had a Karnofsky score of <or=70, and 18 (56%) had clinical stage IV sNHL. The CD4 cell count median value was 111 cells/microL (n = 25). Twenty-four cases (73%) were B-cell sNHL, and 9 cases (27%) were T-cell sNHL, both from peripheral cells. Nineteen cases of sNHL were extranodal: 15 of B-cell origin and 4 of T-cell origin. Eighteen cases of B-cell sNHL had diffuse large cell histologic findings, and all cases of T-cell sNHL were unspecified. Although there were no significant differences in clinical characteristics between phenotypes, patients with T-cell sNHL had less aggressive disease and a better survival rate.

CONCLUSIONS

A high proportion of T-cell sNHL cases was found at an HIV reference center in Peru. Clinical characteristics were similar between B-cell and T-cell lymphoma patients. T-cell lymphoma was less aggressive, and patients with T-cell lymphoma had a better survival rate than those with B-cell lymphoma.

Occurrence and Management of Opportunistic Infections Associated with HIV/AIDS in Asia

Illnesses, diseases and malignancies occur among HIV-infected individuals along a continuum. These are directly correlated with the degree of immune suppression and are caused by common patho gens and opportunistic infections. In decreasing order offrequency, frequent opportunistic infections and malignancies that occur in Asia are: Mycobacterium tuberculosis, Cryptococcus neoformans, Candida spp., Herpes simplex, Cryptosporidium parvum, Pneumocystis carinii, Toxoplasma gondii, non-Hodgkin's lymphoma and Kaposi's sarcoma. The association of morbidityand mortality due to co-infection with HIV and M.tuberculosis has become more evident in the region. Natural history studies conducted in Mumbai and Bangkok have reported incubation periods from infection to AIDS of eight and nine years respectively. Despite the advent of antiretroviral therapy (ART) and improved affordability of the generic drugs, only 30,000 (2 to 3 per cent) of the estimated 1.3 million eligible persons with AIDS in South Asia are presently on AR T. Apparently, the focus of the low-cost care in the region still continues to be of care and management of prevalent opportunistic infections. As care practices start to include ART over the next few years, there will be consequent change in the occurrence of opportunistic infections and need for their prophylaxis.