Biomedical subjects

M Konde

Publications and source records attributed to M Konde.

4 recordsLinked to original sources

PubMed1994

Goitrous endemic in Guinea.

We identified a major goitrous area in the Republic of Guinea, characterised by an overall goitre prevalence of 70% in adults. Thyroid swelling was sometimes present at birth and affected 55% of schoolchildren. A difference between sexes appeared at puberty. Endemic cretinism, mainly in its myxoedematous form, was found in about 2% of goitrous patients. In this region, iodine deficiency is the primary causative factor (median urinary concentrations of 16 micrograms/L, and in 69% of inhabitants below the critical threshold of 20 micrograms/L). The diet contained substantial amounts of thiocyanate anions (median 6 mg/L in urine and in 27%, more than 10 mg/L) likely to further depress iodine bioavailability. Other dietary compounds, notably flavonoids were suspected to contribute. Overall nutritional and general health appeared satisfactory. The affected population is borderline euthyroid with a trend towards hypothyroidism in protracted disease. This area of Guinea may be regarded as the epicentre of the west African endemic and as one of the most severely goitrous regions ever described, requiring urgent public health measures.

Adolescent↗

PubMed1993

Use of a rapid test and an ELISA for HIV antibody screening of pooled serum samples in Lubumbashi, Zaire.

Pools with a size of 3 and 5 were prepared by mixing one HIV confirmed HIV-1 seropositive serum with either 2 or 4 HIV seronegative sera at the Regional HIV Laboratory in Lubumbashi, Zaire. These pools were assessed in a blind fashion by ELISA (Vironostika anti-HTLV-III microELISA system, Organon Technika). Similarly constituted pools of 3 samples were assayed by a rapid test with visual reading (HIVCHEK 1 + 2, Dupont de Nemours). With the HIVCHEK, pooling was achieved on the test device itself by dropping consecutively 3 different serum samples on the devices's membrane. After the last serum was soaked in, wash fluid and conjugate were added. Results of the pooling experiments were compared with testing sera individually. The ELISA results from pools and from individual tested samples matched completely if, and only if, the final dilution of individual samples in the reagent medium was the same as recommended by the manufacturer for testing of individual samples. With the HIVCHEK a sensitivity of 99-100% was obtained with pooled sera. Both approaches seemed sensitive enough to enable their use for screening of blood donors and patient management, but a prospective study to validate these preliminary results is necessary.

Democratic Republic of the Congo↗

PubMed1992

Prevention of blood-borne HIV transmission using a decentralized approach in Shaba, Zaire.

OBJECTIVE: To prevent blood transfusion-acquired HIV infection with a decentralized approach to HIV screening of blood donors, using an instrument-free rapid test. SETTING: Shaba province, Zaire (496,877 km2). METHODS: The programme consisted of training health-care workers, distribution of a rapid HIV-antibody test (DuPont's HIVCHEK) for screening of all blood donations, and quality control of testing by a regional reference centre. RESULTS: Over a 2-year period, 11,940 rapid tests were distributed to 37 hospitals, covering 75% of all hospital beds outside the copper mine's health system in Shaba. Eighty-five per cent of the tests were used to screen blood donors (5.4% positive test rate) and 13% to test patients (39.7% positive test rate). At least 265 cases of HIV-positive blood donation were prevented, at an estimated cost of 137-279 ECU per case. Only 26% of initially positive specimens reached the central laboratory for supplemental testing, and sterile transfusion equipment and blood-grouping reagents were frequently unavailable. The lack of transport and communications and a deteriorating health system were major constraints. CONCLUSIONS: District hospitals in Africa are often long distances from major cities, difficult to reach for most of the year, and perform a small number of transfusions. In this context a classical centralized regional blood bank may not be a feasible option to ensure safe blood transfusions. However, safe blood transfusion can be achieved with a decentralized approach using a rapid test, provided that minimum standards of health-care services are available.

Blood Banks↗

PubMed1991

A simplified and less expensive strategy for confirming anti HIV-1 screening results in a diagnostic laboratory in Lubumbashi, Zaire.

The conventional algorithm for HIV testing based on the confirmation of all positive anti-HIV screening reactions by Western blot (WB) is too expensive for developing countries. We investigated the validity of confirming positive screening assay reactions by a second screening test, limiting the use of the supplemental assay to the discrepant test results (algorithm 3), or screening all sera with 2 different assays and retesting all discrepant results by a supplemental assay (algorithm 4) on a panel of 519 sera in a regional reference laboratory in Lubumbashi, Zaire. Combining the Vironostika anti-HTLV-III ELISA with HIV Chek 1 + 2 or Clonatec Rapid HIV 1/2 Ab on all samples and retesting the discrepant results in WB or a line immunoassay (INNO-LIA) (algorithm 4), yielded a sensitivity of 100% and specificities of 98.4% and 99.0% respectively, at costs of 7.3 US $ and 9.3 US $ per test, respectively, for a 40% prevalence of HIV antibody positive samples. The conventional algorithm scored a sensitivity of 97.1% and a specificity of 100% for 11.3 US $ per test. The testing strategy of combining HIV Chek 1 + 2 and Clonatec Rapid HIV 1/2 Ab, an interesting option for small isolated centra, had a 96.6% sensitivity, but yielded only a slightly better specificity of 99.0%, as compared to 97.8% for HIV Chek alone. The price of combining the two simple assays using algorithm 3 was 6.8 US $ per test, using algorithm 4 was 10.6 US $. HIV testing strategies based on ELISA and a simple HIV test are a valuable alternative for reference laboratories faced with a high prevalence of HIV positive samples.

AIDS Serodiagnosis↗