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J Gardon

Publications and source records attributed to J Gardon.

18 recordsLinked to original sources

Ocular findings after ivermectin treatment of patients with high Loa loa microfilaremia.

Hemorrhages in the palpebral conjunctiva (HPCs) have been recorded in patients living in an area endemic for loiasis who developed serious reactions after ivermectin treatment. A study was designed to evaluate the frequency of these lesions, and to identify risk factors associated with their appearance. The conjunctivae of 1,682 patients who complained of reactions were systematically examined. HPCs were found in 41 patients. The initial mean Loa loa microfilaremia in the individuals with HPCs was 14,900 microfilariae (mf) per mL, as compared with 14.5 mf/mL in the other patients. Mansonella perstans microfilaremia and male gender were also associated with HPCs. Post-treatment fundus examinations were performed on 37 patients, and a close relationship was found between the occurrence of HPCs and the presence of retinal lesions. The vascular pathological processes leading to the ocular lesions may be similar to those which occur at the cerebral level in patients harboring high L. loa microfilaremia who develop neurologic troubles after ivermectin treatment. Retinal lesions may represent a special feature of the Loa-related encephalopathies useful for differential diagnosis, and the HPCs may be useful as an alarm sign to identify those individuals who might develop serious reactions after ivermectin treatment.

Adolescent↗

Three probable cases of Loa loa encephalopathy following ivermectin treatment for onchocerciasis.

Over the past nine years, more than 12 million people exposed to Onchocerca volvulus infection have received at least one dose of ivermectin, almost all without serious adverse reactions. Since 1991, however, several cases with neurologic manifestations, including coma, have been reported after ivermectin treatment of persons infected with O. volvulus who also had concomitant Loa loa infection with very high microfilaremia (> 50,000 microfilariae/ml of blood). In 1995, four criteria were established to define probable cases of Loa encephalopathy temporally related to treatment with ivermectin (PLERI). The present paper describes three PLERI cases recorded in Cameroon and compares them with two others reported previously. Disorders of consciousness began 3-4 days after treatment. The objective neurologic signs were variable. The conditions improved favorably in three patients who benefited from early hospitalization and good nursing; their disorders of consciousness lasted only 2-3 days; the results of clinical examination became normal after one month and electroencephalographic abnormalities disappeared after 5-7 months. Conversely, late diagnosis and delay in proper management in two others probably led to worsening of the condition and to fatal outcome related to the usual complications of coma. In addition to these cases, patients w with high Loa microfilaremia also developed milder neurologic manifestations causing functional impairment lasting for at least one week after treatment. Before launching mass ivermectin distribution programs to control onchocerciasis in central Africa, communities in which the intensity of concomitant L. loa microfilaremia is high need to be identified, and specific educational measures and monitoring strategies should be developed and applied before they are treated.

Adolescent↗

Serious reactions after mass treatment of onchocerciasis with ivermectin in an area endemic for Loa loa infection.

BACKGROUND: In 1995, the World Bank launched an African Programme for Onchocerciasis Control to eliminate Onchocerca volvulus disease from 19 African countries by means of community-based ivermectin treatment (CBIT). Several cases of encephalopathy have been reported after ivermectin in people heavily infected with microfilariae of Loa loa (loiasis). We assessed the incidence of serious events in an area where onchocerciasis and loiasis are both endemic. METHODS: Ivermectin (at 150 micrograms/kg) was given to 17877 people living in the Lékié area of Cameroon. 50 microL samples of capillary blood were taken during the daytime before treatment from all adults (aged > or = 15 years), and the numbers of L loa and Mansonella perstans microfilariae in them were counted. Patients were monitored for 7 days after treatment. Adverse reactions were classified as mild, marked, or serious. Serious reactions were defined as those associated with a functional impairment that required at least a week of full-time assistance to undertake normal activities. We calculated the relative risk of developing marked or serious reactions for increasing L loa microfilarial loads. Risk factors for serious reactions were identified and assessed with a logistic regression model. FINDINGS: 20 patients (0-11%) developed serious reactions without neurological signs but associated with a functional impairment lasting more than a week. Two other patients were in coma for 2-3 days, associated with L loa microfilariae in cerebrospinal fluid. Occurrence of serious reactions was related to the intensity of pretreatment L loa microfilaraemia. The relative risk of developing marked or serious reactions was significantly higher when the L loa load exceeded 8000 microfilariae/mL; for serious reactions, the risk is very high (odds ratio > 1000) for loads above 50000 microfilariae/mL. INTERPRETATION: Epidemiological surveys aimed at assessing the intensity of infection with L loa microfilariae should be done before ivermectin is distributed for onchocerciasis control in areas where loiasis is endemic. In communities at risk, monitoring procedures should be established and adhered to during CBIT so that people developing serious reactions may receive appropriate treatment.

Adolescent↗

Prevalences of Loa loa microfilaraemia throughout the area endemic for the infection.

Several cases of encephalopathy recorded in Cameroon since 1991 were in patients with very high, coincident, Loa loa microfilaraemias who had been treated with ivermectin for onchocerciasis. There was thus an urgent need to identify those areas where loiasis is hyperendemic, and where specific monitoring procedures should be developed if large-scale ivermectin treatment of onchocerciasis is to be implemented. In the present review, the available data on Loa endemicity are detailed and maps showing the prevalence of Loa microfilaraemia throughout the area endemic for the infection are presented. By superimposing these maps on those which show where onchocerciasis is meso- or hyper-endemic, it is now possible to identify several areas, in south-eastern Nigeria, southern and central Cameroon, the south of the Central African Republic, Equatorial Guinea, Gabon, and the north and west of the Democratic Republic of the Congo (ex-Zaire), where ivermectin treatment, although indicated, is most likely to lead to adverse reactions because of L. loa infections. Additional surveys, to delineate the areas highly infected with L. loa more accurately, are required.

Adolescent↗

[AIDS and health personnel in Ivory Coast].

During the second half of 1993, a survey to assess awareness, attitudes, habits, and behavior with regard to HIV and AIDS was performed among health care workers in the Cote d'Ivoire. A total of 90 health care workers, 42 in Abidjan and 48 in Daloa, were surveyed. The majority (87%) were women. Understanding of the terms "AIDS" and "seropositivity" was good as was knowledge of AIDS-related symptoms. Awareness was better among newly recruited workers and nurses than among orderlies. Appreciation of risk was strongly linked with the notion of high-risk population. The occupational nature of the risk was clearly understood and anxiety in this regard was increased by uncertainty as to modes of secondary transmission and lack of preventive measures. On the individual and personal level protection consisted mainly in reducing the number of partners and outside activities. There was a great demand for training and information. As a result of the uncertainties revealed in this survey there appears to be a reluctance or refusal to perform certain procedures or treat certain patients and even a tendency to abandon the health care profession.

Acquired Immunodeficiency Syndrome↗

[Secondary effects of the treatment of hypermicrofilaremic loiasis using ivermectin].

In the last ten years ivermectin appeared an efficient and safe alternative to diethylcarbamazine which is known to induce severe adverse reactions in loiasis, including encephalitis. After these results, large scale ivermectin treatments against onchocerciasis were carried out in Central Africa where loiasis is also endemic; and seven cases of severe reaction were reported in Cameroon since 1991, during these mass ivermectin treatments. In order to study adverse reactions in patients harbouring high load of Loa loa microfilariae (mf), we realized careful hospital based treatment in 112 patients with more than 3,000 mf/ml (ml) blood. Patients received once 200 micrograms ivermectin per kilogram at day 0 (D0). Clinical examination was made daily during the four following days (D1 to D4). Blood and urine samples were analysed before treatment and at D1 and D3. Lumbar puncture was made at D1 for 39 patients with more than 10,000 mf/ml; at D3 for the 49 following patients without consideration for the level of parasitaemia, and at D0 and D3 for ten voluntary patients. For analysis the patients were distributed in 3 groups according to initial parasitaemia: the first group included 50% out of the patients, those whose parasitaemia was fewer than 15,000 mf/ml blood; the second group included 25% patients whose parasitaemia was between 15,000 and 30,000 mf/ml; the third group included the last 25% patients whose parasitaemia was higher than 30,000 mf per ml blood. Adverse reactions were observed in 71% out of the patients. Symptoms described were fever, pruritus, headache, arthralgia. Most symptoms appeared 24 to 36 hours after treatment. Temperature increased significantly in group 3. Microfilaraemia decreased by 85% in the 3 groups during the 4 days following treatment. C-reactive-protein increased dramatically after treatment in all patients (p < 10(-4)). Some patients presented blood in urine in three groups but haematuria reached 35% of patients in group 3. Proteinuria is noted among 33% of all patients but 20% in group 1 and 2 versus 70% in group 3. Loa loa mf were observed in urine of half the patients, but in low amounts (< 10 mf per 50 ml urine). In cerebro-spinal fluid (CSF), some mf appeared at D1 or D3 in people heavily infected with Loa loa, reaching 80% of the patients of group 3. LP made at D0 in ten patients with parasitaemia higher than 30,000 mf/ml blood confirmed that CSF was naturally microfilaria free before treatment. One patient presented severe troubles with fever, asthenia and conscience troubles beginning at D3, reactive coma at D4, renal impairment with transitory anuria; progressive improvement in 2 weeks and complete recovery at D22; he presented 102 mf/ml CSF at D6. The study confirmed that ivermectin treatment is generally well tolerated. Among people with high Loa loa parasitaemia the symptoms after treatment are frequent but mild. However severe cases with conscience troubles are possible, and may occur in about 1% of subjects with more than 3,000 mf/ml blood. Severity of adverse reactions was linked to level of parasitaemia before treatment. The critical parasitaemia level which could lead to expect serious adverse effects seems to be 30,000 ml/ml blood. These informations should induce carefulness to carry out large scale treatments against filariosis in endemic areas of Loa loa.

Adult↗

[Comparison between various methods of pregnancy screening during a large-scale ivermectin treatment in Cameroon].

During a mass treatment with ivermectin which is contraindicated to pregnant women, authors made a screening for pregnancy by questioning 2,580 women from 15 to 45 years old. 1,409 of these women were also interrogated by a female physician assisted by a native matron to detect pregnant women. In 1,798 women, at least one immunological pregnancy test has been used in the field. A nine months follow-up was made to check answers. Women's knowledge led to a good appreciation of pregnancy as they correctly appreciated their pregnancy from the second month: specificity was good (98%) but sensitivity was moderate (71%). Conclusions made by gynecological team after detailed questionnaire were more sensitive (80%), but specificity decrease dramatically to 59%. Combinations of several items in the questionnaire showed no benefit. Sensitivity of the various immunological pregnancy tests tried was included in 70 to 90% and specificity was varying from 87 to 97%. Simple questioning of women was the most efficient method (efficiency value was 94% against 63% for interview and 92% for pregnancy tests). However, the use of this method induced the risk that about 29% of women have been treated although they were pregnant.

Adolescent↗

[Epidemiological features of retroviral infection by HTLV-1 in central Africa].

Subsaharian Africa is the most important reservoir of HTLV1 virus but its epidemiology is not well-known. The authors have studied from 1987 to 1990 the situation in 6 countries in Central Africa. The already described routes of transmission are present: through blood transfusions (but it's not such a common practice), heterosexual transmission (but it doesn't seem to be as important as in other continents), and mother to child transmission through breast feeding. Nevertheless, environmental factors--which have to investigated--could play a role for transmission, among them one could think to vectors and parasites.

Adolescent↗

Proposals for a new therapeutic strategy for simple Plasmodium falciparum malaria attacks in Cameroon.

From simplified in vivo tests, authors set up a cartography of the sensitivity of Plasmodium falciparum to amino-4-quinolines in Cameroon; they also evaluated the clinical and parasitological efficacy of different therapeutic protocols which make use of amino-4-quinolines, quinine, mefloquine and halofantrine. All these drugs are administered orally. They recommend maintaining home medication with chloroquine at the dose of 25 mg/kg over 3 days, conserving quinine for use in the case of a possible failure. The use of most recent antimalarials can be proposed only as a last resort.

Administration, Oral↗

Ivermectin-based control of onchocerciasis in northern Cameroon: individual factors influencing participation in community treatment.

A study aimed at determining individual factors associated with participation in community treatment with ivermectin was conducted in a village hyperendemic for onchocerciasis in northern Cameroon. The respective influences of sex, age, place of residence, distance between the compound and the dosing point, compound size, and participation in treatment by authoritative individuals in the compound was evaluated using univariate and multivariate analysis. Participation in treatment was closely associated with the attitude of the compound heads. Participation of compound heads in treatment increased as the household size increased, and as the distance to the distribution point diminished. This may be explained by the fact that getting information on health programmes is easier in large households whose members are involved in various social activities, and in compounds located near the village centre. Staff involved in health education should take this issue into account, and try to ensure circulation of information particularly to those living in small or remote compounds.

Adolescent↗