Risk factors for high anti-HHV-8 antibody titers (> or =1:51,200) in black, HIV-1 negative South African cancer patients: a case control study

Mutual detection of Kaposi's sarcoma-associated herpesvirus and Epstein-Barr virus in blood and saliva of Cameroonians with and without Kaposi's sarcoma

Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) are prevalent in sub-Saharan Africa, together with HIV; the consequent burden of disease is grave. The cofactors driving transmission of the two viruses and pathogenesis of associated malignancies are not well understood. We measured KSHV and EBV DNA in whole blood and saliva as well as serum antibodies levels in 175 Cameroonians with Kaposi's sarcoma and 1,002 age- and sex-matched controls with and without HIV. KSHV seroprevalence was very high (81%) in controls, while EBV seroprevalence was 100% overall. KSHV DNA was detectable in the blood of 36-46% of cases and 6-12% of controls; EBV DNA was detected in most participants (72-89%). In saliva, more cases (50-58%) than controls (25-28%) shed KSHV, regardless of HIV infection. EBV shedding was common (75-100%); more HIV+ than HIV- controls shed EBV. Cases had higher KSHV and EBV VL in blood and saliva then controls, only among HIV+ participants. KSHV and EBV VL were also higher in HIV+ than in HIV- controls. Cases (but not controls) were more likely to have detectable KSHV in blood if they also had EBV, whereas shedding of each virus in saliva was independent. While EBV VL in saliva and blood were modestly correlated, no correlation existed for KSHV. Numerous factors, several related to parasitic coinfections, were associated with detection of either virus or with VL. These findings may help better understand the interplay between the two gammaherpesviruses and generally among copathogens contributing to cancer burden in sub-Saharan Africa.

Anogenital Lesions: Kaposi's Sarcoma and Its Mimicks

Kaposi's sarcoma (KS) is a low-grade vascular neoplasm associated with human herpes virus-8 (HHV-8) infection, and, in the epidemic form, with the human immunodeficiency virus (HIV). Although HHV-8 is present in all body fluids and is sexually transmitted, there are surprisingly few reports of anogenital KS. Clinically, especially in HIV/KS endemic areas, dark stained skin patches or nodules are prone to misdiagnosis, especially in dark-skinned individuals. Therefore, a biopsy is recommended. The histologic appearance spans a broad spectrum of KS and non-KS lesions; therefore, the final diagnosis should be confirmed by HHV-8 immunohistochemistry. We report a series of 36 anogenital biopsies from a group of 16 documented HIV-positive patients; in 20 the HIV serostatus was unknown. There were ten KS (five in HIV-positive patients), and 26 non-KS (11 in HIV-positive subjects) lesions. In the era of HIV/AIDS, anogenital lesions may be the first manifestation of KS in immunocompromised individuals and should be biopsied. The histological diagnosis should be confirmed by HHV-8 immunohistochemistry.

Seroprevalence and risk factors of Kaposi's sarcoma-associated herpesvirus infection among the general Uygur population from south and north region of Xinjiang, China

Background

Kaposi sarcoma (KS) is a complex multifocal neoplasm and is the major cause of death for about 50% of acquired immunodeficiency syndrome (AIDS) patients. Kaposi's sarcoma-associated herpesvirus (KSHV) is an oncogenic virus with a causal role in the development of all types of KS. KS is prevalent among the Uygur people in Xinjiang, especially in south area. Here we carried out a cross-sectional study among 1534 general Uygur individuals from south and north region of Xinjiang to assess the seroprevalence of KSHV and to identify the potential correlation between KSHV seroprevalence and KS incidence.

Results

Seroprevalence of KSHV in South and North Xinjiang was 23.1% and 25.9%, respectively. Older age was independently associated with higher KSHV seroprevalence. In subjects from South Xinjiang, lower educational level and reported drinking were each independently associated with higher KSHV seroprevalence. Furthermore, the antibody titer was significantly lower in both south and north KSHV seropositive individuals compared with KS patients, as analyzed by gradient dilution (P < 0.001).

Conclusion

KSHV is highly prevalent in the general Uygur population in both South and North Xinjiang. Interestingly, the infection rate of KSHV in these two geographical areas did not correlate well with KS incidence. Perhaps unknown factors exist that promote the progression of KSHV infection to KS development in the local minority groups.

Effects of tobacco smoking on cancer and cardiovascular disease in urban black South Africans

Demographic and lifestyle information from 9690 black patients diagnosed with cancer or cardiovascular disease was collected in an ongoing case–control study in Johannesburg, South Africa. Compared to never smokers, the odds ratio (OR) for lung cancer among current smokers was 16.3 (95% confidence interval (CI), 9.6–27.6) for men and 6.4 (95% CI, 4.0–10.4) for women. The corresponding OR for other smoking-related cancers was 4.6 (95% CI, 3.7–5.7) among men and 1.9 (95% CI, 1.6–2.2) among women, and for cardiovascular disease, 3.4 (95% CI, 2.1–5.4) among men and 1.5 (95% CI, 1.1–2.1) among women. Risks were higher among smokers than former smokers, and all risk estimates increased with increasing levels of smoking duration and intensity. Non-electric domestic fuel was associated with approximately 60% increase in the risk of smoking-related cancer, but not cardiovascular disease. Risks for cancers of cervix, oesophagus, oral cavity/pharynx, stomach, larynx, pancreas and anogenital region, as well as squamous cell carcinoma of skin were all significantly higher among current than never-smokers, with ORs ranging from 1.5 for cervix (95% CI, 1.2–1.8) to 14.7 for larynx (95% CI, 7.2–30). The risks of tobacco-related disease reported here are similar to that currently observed in Western countries, even though cigarette consumption is relatively low in this population.

Traditional home-brewed beer consumption and iron status in patients with esophageal cancer and healthy control subjects from Transkei, South Africa

Consumption of home-brewed beer is associated with dietary iron excess and a high incidence of esophageal cancer in Transkei, South Africa. We examined the relationship between home-brewed beer consumption and body iron status in 234 patients with esophageal squamous cell carcinoma and 595 control subjects residing in Transkei. Subjects were screened for iron overload using transferrin saturation >45%, and/or serum ferritin >200 microg/l for women and >300 microg/l for men. A questionnaire was administered to all subjects, and iron content of randomly selected home-brewed beer samples was determined. The iron content of home-brewed beer was 258-fold higher than the commercial Castle Lager beer produced by South African Breweries. The prevalence of home-brewed beer consumption was 30.1% in esophageal cancer patients and 15.5% in control subjects and was found not to be a risk factor for esophageal cancer after adjustment for age, sex, and tobacco consumption (male subjects, odds ratio= 1.6 (95% confidence interval [CI]: 0.7-4.5); female subjects, odds ratio=1.7 (95% CI: 0.7-4.5). Iron overload as determined by transferrin saturation and elevated serum ferritin was observed in 4.3% of patients with esophageal cancer and 0.7% of control subjects and was not associated with the consumption of home-brewed beer. Consumption of home-brewed beer is not a risk factor for esophageal cancer and is not linked with iron overload in either cancer patients or control subjects; however, iron overload is likely to result from a combination of dietary intake and a genetic component.

Kaposi's sarcoma-associated herpesvirus: clinical, diagnostic, and epidemiological aspects

Kaposi's sarcoma-associated herpesvirus (KSHI) is one of the few viruses proven to be associated with tumorigenesis in humans. Its causal association with all clinical and epidemiological variants of Kaposi's sarcoma (KS) is well established. KSHV is also involved in the pathogenesis of primary effusion lymphoma (PEL) and a subset of multicentric Castleman's disease (MCD). Possible associations of KSHV with other clinical settings have been extensively examined. The findings from several of these studies are contradictory and are yet to be resolved. Concentrated effort over the last decade, since the initial discovery of KSHV, led to the development of several experimental systems that resulted in a better comprehension of the biological characteristics of KSHV and set the stage for the understanding of mechainisms by which diseases are induced by the virus. The development of molecular, histological, and serological tools for KSHV diagnosis allowed researchers to track the transmission and to study the epidemiology of KSHV. These assays have been applied, in particular in ambiguous cases, in order to confirm clinically and pathologically based diagnoses. Here, we review the advances in the clinical, experimental, diagnostic, and epidemiological research of KSHV.

Aspects épidémiologiques de l'herpèsvirus humain 8 (HHV-8) et du sarcome de Kaposi

HHV-8 belongs to the herpesviridae family, to the gammaherpesvirinae subfamily, and to the rhadinovirus genus. Whereas several viral homologues exist in non human primates, HHV-8 is the only rhadinovirus known in human. HHV-8 is mainly the etiological agent of the four clinico-epidemiological forms of Kaposi's sarcoma (classic, endemic, post-transplant, and epidemic/HIV associated). HHV-8 is not an ubiquitous virus. It is mainly endemic in areas of high endemicity for classic or endemic Kaposi's sarcoma including the Mediterranean area and most of East and Central Africa. Its prevalence varies in the adult population, from less than 5% in the USA and Northern Europe to more than 50% in some regions of the African continent and around 10 to 20% in Italy and Greece. One can estimate that several hundred million people are HHV-8 infected worldwide with at least 150 million on the African continent. Modes of infection seem different in low and highly endemic areas. In low endemic areas, HHV-8 is mainly present in the male homosexual population, where this herpesvirus is transmitted during sexual contacts. In contrast, in highly endemic areas, as Central Africa, HHV-8 transmission occurs mainly from mother to child and between siblings. Heterosexual transmission remains low as well as transmission through blood products. Saliva seems to play a major role in the viral transmission, and may be a reservoir for HHV-8.

Kaposi's sarcoma in kidney transplant recipients: a 23-year experience

BACKGROUND

Kaposi's sarcoma (KS) is a relatively common malignancy after kidney transplantation, accounting for up to 80% of all malignancies in developing countries.

AIM

To assess the frequency of KS in renal transplant recipients, and determine the impact of demographic factors, immunosuppression and treatment options.

DESIGN

Retrospective study in a single centre in South Africa.

METHODS

Charts and pathology reports of 542 recipients of 623 kidney allografts treated at our institution between 1976 and 1999 were reviewed.

RESULTS

After a mean follow-up of 6.4 years, 21 (3.9%) recipients had KS, representing 47.7% of all post-transplant malignancies. KS accounted for more post-transplant cancers in non-White than White patients (79.1% vs. 11.7%, p < 0.001). KS was equally common in males and females, and was not more frequent under cyclosporine. Skin involvement was universal; visceral disease occurred in six patients (28.6%). Sixteen (94.1%) patients with limited skin disease and two (100%) with superficial nodal disease responded to withdrawal or reduction of immunosuppression. Renal function was preserved when immunosuppression was reduced instead of withdrawn (p = 0.02). Patients with vital organ involvement succumbed rapidly to KS. Post-mortem examination revealed more extensive disease than was suspected clinically.

DISCUSSION

Ethnic differences exist in the frequency of KS in patients residing in the same geographical area. Since withdrawal results in graft loss, reducing immunosuppression should be first-line treatment for patients with disease limited to skin, and possibly for disease of the superficial lymph nodes. The malignant behaviour of KS, and extent of pathological involvement, cast doubt on the idea that KS is a hyperplasia rather than a true malignancy.