Burkitt's Lymphoma in Africa; a Review of the Epidemiology and Etiology

Burkitt's lymphoma (BL) was first described in Eastern Africa; initially thought to be a sarcoma of the jaw. Shortly it became well known that this was a distinct form of Non Hodgkin's lymphoma.The disease has given insight in all aspects of cancer research and care. Its peculiar epidemiology has led to the discovery of Epstein Barr virus (EBV) and its importance in the cause of several viral illnesses and malignancies.The highest incidence and mortality rates of BL are seen in Eastern Africa. BL affects mainly children; and boys are more susceptible than girls. Evidence for a causal relationship between EBV and BL in the endemic form is fairly strong. Frequency of association between EBV and BL varies between different patient groups and different parts of the world. EBV may play a role in the pathogenesis of BL by deregulation of the oncogene c-MYC by chromosomal translocation.Although several studies suggest an association between malaria and BL; there has never been a conclusive population study in support of a direct role of malaria in causation of BL.The emergence of HIV and a distinct subtype of BL in HIV infected have brought a new dimension to the disease particularly in areas where both HIV and BL are endemic. BL has been reported as a common neoplasmin HIV infected patients; but not in other forms of immuno-depression; and the occurrence of BL seems to be higher amongst HIV positive adults; while the evidence of an association amongst children is still disputed.The role of other possible risk factors such as low socio-economical status; exposure to a plant species common in Africa called Euphorbiaceae; exposure to pesticies and to other infections such as schistosomiasis and arbovirus (an RNA virus trans- mitted by insect vectors) remain to be elucidated

The value of a clinical definition for epidemic KS in predicting HIV seropositivity in Africa

Kaposi's sarcoma (KS) in African adults can present in endemic (non-HIV-related) and epidemic (HIV-related) forms. We evaluated the usefulness of a clinical case definition for epidemic KS in predicting HIV seropositivity. A total of 235 patients with KS presenting to the Uganda Cancer Institute from January 1; 1988 to March 31; 1990 were evaluated with history and physical examination. Symptomatic patients underwent chest radiography and upper gastrointestinal endoscopy. One hundred seventy-four patients (80pc) underwent HIV ELISA testing with Western blot confirmation. The clinical case definition had a 91pc sensitivity and a 95pc specificity in predicting HIV seropositivity. Oral KS was the most sensitive specific site of involvement in predicting HIV seropositivity. The clinical case definition is useful in assessing patients to determine prognosis and likelihood of responding to aggressive therapy

To Establish Haematological Reference Ranges among Indigenous Normal Ugandans

Methodology: Eligible subjects were HIV-1 negative; with no demonstratable medical or emotional problems. The parameters considered were absolute lymphocyte counts (AL C); absolute CD4 and CD8 (ACD4; ACD8) and CD4/CD8 count ratio (ABSR). The central 95area under the distribution curve (ACD) of the parameters of interest was considered as well as mean distributions between the sexes. Results: 183 subjects; 69(37.7) females and 114 (62.3) males were submitted to the study. The 95range for the combined groupe for ALC was 1452.5 - 4447.5; for ACD4 558.6-2332.8; for ACD8 252.0-1396.1; and for ABSR 0.682 - 4.37. There was a significant difference (p0.5) in mean ALC and mean (ABSR between sexes. Discussion: This p[ilot study was necessitated by the absence of up-to-date haematological and especially immunologic parameters (CD4; CD8) among normal Ugandans. Currently many laboratories and clinicians use North American and European haematologic reference; and also use various manual methods for determination of CD4 and CD8. These ranges which were established with more accurate method of flow cytometry gives a scientists in Uganda (and by implication Central Africa) and calls for a more extensive study to establish more representative and accurate haematological and immunological parameters