Sebastian Lucas

Disease in children infected with HIV in Abidjan, Cote d'Ivoire.

Abstract Objective: To document the range of disease in African children infected with HIV. Design: Necropsy results in consecutive children aged 1 month or more who were HIV positive and in children who were HIV negative for comparison; IgA western blots on serum samples from children under 2 years of age who were positive for HIV-1 to test the validity of routine HIV serology. Setting: Largest hospital in Abidjan, Cote dIvoire. Subjects: 78 children who were HIV positive and 77 children who were HIV negative on whom a necropsy was performed; their median ages at death were 18 and 21 months respectively. 36 HIV positive children and 29 HIV negative children were 1-14 months old; 42 HIV positive and 48 HIV negative children were >/=15 months old. Main outcome measures: Cause of death and prevalence of diseases confirmed pathologically. Results: Respiratory tract infections were more common in HIV positive than in HIV negative children (73 (94%) v 52 (68%); P<0.05), and were aetiologically heterogeneous. Pneumocystis carinii pneumonia was found in 11 out of 36 (31%) HIV positive children aged <15 months, but in no HIV negative children. Among older children measles was more common in HIV positive children (8/42 (19%) v 2/48 (4%); P<0.06). Pyogenic meningitis was present in similar proportions of HIV positive and HIV negative children aged <15 months (7/36 (19%) and 7/29 (24%)). In HIV positive children tuberculosis (1/78), lymphocytic interstitial pneumonitis (1/78), and HIV encephalitis (2/78) were rare. Conclusions: There is greater overlap between diseases associated with HIV infection and other common health problems in African children than there is in adults. Compared with adults, HIV positive children had a high prevalence of P carinii pneumonia and a low prevalence of tuberculosis. Measles, but not malaria, was associated with HIV infection. Key messages Key messages In regions with a poor clinical infrastructure necropsy provides information that cannot be obtained otherwise This survey of children aged under 1 month to 12 years who died in Abidjan, Cote dIvoire, found that a fifth were positive for HIV infection with a median age at death of 18 months Almost a third of HIV positive children under 15 months old had Pneumocystis carinii pneumonia, a rate similar to that found in affected children in industrialised countries but much higher than the rate in affected adults in Abidjan Measles was more common in children who were HIV positive, suggesting that vaccination would be a feasible intervention

Use of polymerase chain reaction to assess efficacy of leprosy chemotherapy

The assessment of chemotherapy efficacy in leprosy is difficult, since the only reliable method for determining whether the causative organism, Mycobacterium leprae, is viable depends on its growth in mouse foot pads. In an attempt to replace this expensive, time-consuming test, methods based on the polymerase chain reaction (PCR) have been developed. These methods depend on detection of DNA, which is more susceptible to degradation on cell death than are other cell components, so should be a more accurate indicator of viability. We have used a specific PCR assay to detect M leprae DNA in skin biopsy samples from leprosy patients. By use of limiting dilution PCR (LD-PCR), the concentration of M leprae DNA in the original sample could be measured. The DNA concentration was more closely correlated with the morphological index (derived from a staining technique that distinguishes morphologically intact and damaged bacteria) than with the number of bacteria visible (bacterial index, BI, which counts both alive and dead bacteria). In a longitudinal study of multibacillary patients on multi-drug therapy, skin biopsy samples were collected before treatment and 3, 6, 12, and 24 months after the start of therapy. While the BI showed little or no change during treatment, the number of genomes detected by PCR fell sharply, in parallel with the MI. We propose that PCR can be used as a rapid measure of M leprae viability and that this approach can be used for monitoring individual leprosy patients and for assessment of existing and new regimens. The method may be applicable to other infectious diseases in which culture of the causative organism is slow or impossible.

Does the immunopathology induced by schistosome eggs potentiate parasite survival

Infection with schistosomes is accompanied by inflammatory lesions resembling delayed hypersensitivity reactions, that are induced by eggs in host tissues. Here Michael Doenhoff and his colleagues demonstrate that T-cell-deprived mice excrete much fewer eggs than do intact control animals. From the results of serum and cell transfer experiments, they conclude that immune processes assist egg expulsion and thus contribute to the parasites success.

Expansion of surveillance case definition for AIDS in resource-poor countries.

The discussions about the expansion of the Centers for Disease Control and Prevention (CDC) surveillance case definition for AIDS in adolescents and adults have not addressed the needs of developing countries which have been using the 1987 CDC definition and the Bangui Caracas and Abidjan definitions. None of these definitions fully includes the indicator diseases (tuberculosis recurrent pneumonia and invasive cervical cancer) that are now part of the expanded CDC definition. In the expanded CDC and European case definitions HIV-associated tuberculosis the commonest infection in AIDS patients in Africa is included. An expanded case definition for resource-poor countries is proposed. An adult (> 12 years) is judged to have AIDS if a test for HIV infection is positive and one or more of the following criteria is present: 1) wasting syndrome (>10% body weight loss with diarrhea or fever for at least 1 month); 2) tuberculosis; 3) candida esophagitis 4) cryptococcal meningitis or chronic neurological disease; 5) Kaposis sarcoma; 6) clinically diagnosed life-threatening pneumonia or sepsis (pneumonia salmonella septicaemia pyomyositis or nonmeningococcal meningitis); and 7) invasive carcinoma of the cervix. HIV serological testing is needed or the Bangui definition could be used where such tests are onerous. Where resources are scarce regular surveys to estimate the incidence and mortality rates of AIDS may be more informative than case counting. A redesigned surveillance for HIV disease would measure the burden and death attributable to HIV a well as encourage early interventions for the infected by making HIV infections and deaths reportable; by monitoring the use of health care resources by HIV-infected persons; and by tracking only the diseases associated with HIV that are of public health importance such as tuberculosis.

Malignant Tumors In Children of Northeastern Zaire A Comparison of Distribution Patterns

In an effort to better understand the epidemiology of cancer in Zaire, a retrospective review of biopsy-proven malignant tumors was undertaken. Of 188 biopsies taken from children aged 0-15 years over a 4.5 year period, 73 (39%) revealed malignancy. Fifty-six percent of patients with malignant tumors were boys. Lymphoma was the most common tumor (28 patients, 15 with Burkitts Lymphoma). Sarcoma (15 patients), carcinoma (8 patients), Wilms Tumor (6 patients), and retinoblastoma (5 patients) were also seen. Lymphomas were most heavily represented in the first 5 years of life, while sarcoma and carcinoma accounted for most of the malignancies in children after 10 years of age. Lymphomas and sarcomas are relatively more common in Zaire than in North America and Europe, while leukemia and central nervous system tumors are notably less common in Zaire. In view of current limitations on health care in rural Zaire, cancer care should be directed toward early diagnosis, quick referral for appropriate surgical care, and use of the limited arsenal of chemotherapy.