Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022568 (keratitis)
 5,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ivermectin seems to be a safe and effective treatment for onchocerciasis when given in a single dose, but less is known about the effects of repeated doses. Also, there seem to be differences in its effectiveness in anterior and posterior segment ocular disease. The ocular effects of ivermectin were studied in 586 villagers who were taking part in a double-blind, placebo-controlled, randomised trial in Sierra Leone. Only those who had received four doses, with 6-month intervals, of ivermectin or placebo were eligible. The 296 ivermectin-treated subjects and the 272 who received placebo were comparable with respect to age, sex, Onchocerca infection, blindness, and visual impairment before treatment. After treatment, the ivermectin group had less anterior segment disease than the placebo group, with significantly lower prevalences of microfilariae in the anterior chamber and cornea, and punctate keratitis (all p less than 0.001), and iritis (p less than 0.05). There was no significant difference in the prevalence of sclerosing keratitis, optic atrophy, or chorioretinitis between the groups. Visual acuities tended to be better in the ivermectin group, but the difference was not significant. There was a small but significant (p less than 0.01) excess of vascular sheathing in the ivermectin group. These differences persisted when subjects who were blind or visually impaired at baseline were excluded from analysis. The long-term effects of ivermectin, particularly on posterior segment disease, need further evaluation. In the mean time, the mass distribution of ivermectin should be promoted for all communities with hyperendemic onchocerciasis at risk of anterior segment disease.
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PMID:Effects of repeated doses of ivermectin on ocular onchocerciasis: community-based trial in Sierra Leone. 168 43

In a double blind study Ivermectin has been compared to a placebo in 234 male and female with onchocerciasis who had more than 20 microfilariae per milligram of skin and moderate ocular involvement. Patient was randomized to receive a simple oral dose of Ivermectin 100, 150 and 200 micrograms/kg or placebo. The following was 12 months. The decrease of microfilarodermia since to the 3rd day was from 72.8 to 79.3% of initial rate. At six months it was more than 91% and more than 87% in 12 months. Ocular microfilariae, initially between 12 and 23 stay lower than 2 at 12 months. Punctuated keratitis disappear and did not recidive still 6 months in patients with persistent microfilariae. Ivermectin produce only few side effects. Negative waves have been observed on ECG but without any clinical signs. The Power efficient dose seen to be 100 micrograms/kg.
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PMID:[Ivermectin and human onchocerciasis. A study of 234 onchocerciasis patients in the Republic of Mali]. 304 72

The conditions were examined for in vitro antibody-mediated adherence of granulocytes to microfilariae of Onchocera volvulus and Dirofilaria immitis. Reactivity in human sera from patients in endemic foci in Sudan was specific for O. volvulus and no reactions were observed with heterologous Onchocerca species or with Mansonella perstans. Microfilariae from skin, nodules or adult female worms were satisfactory targets for cell adherence, and the cells involved were almost exclusively eosinophils. The reaction was inhibited by indomethacin but not by nordihydroguaiaretic acid, an inhibitor of leukotriene production. Agents that slowed or stopped microfilarial motility (e.g. nifedipine, lidocaine, chloroquine) inhibited the reaction, probably by reducing target/cell contact. Ivermectin did not enhance the reaction, and in the absence of cells exerted only slight effects on the movement of microfilariae at higher concentrations (greater than 10 micrograms/ml). Antibody activity was labile, and did not persist well through freeze-thaw cycles. Some differences between homologous and heterologous mixtures (microfilariae/cells/serum) were seen but they could not be resolved satisfactorily. There were no apparent geographical differences between microfilariae from different foci in Sudan. In the D. immitis system neutrophils were the dominant cell type adhering to microfilariae, and the activity was stable to storage and freeze-thaw. No enhancement was detectable with diethylcarbamazine. Antibody activity was absorbable with microfilarial antigens and was reduced by agents that inhibited microfilarial motility. In dogs, adherence-mediating antibody was seen only in amicrofilaraemic animals with occult infection, and in only a minority of these sera. In humans the relationship to clinical findings was less clear, but patients with punctate keratitis were the most likely to have positive serum and were the most reactive in the assay. This system may therefore offer some insights into disease mechanisms in vivo, and its molecular mechanisms deserve further characterization.
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PMID:Cell adherence to microfilariae of Onchocerca volvulus: a comparative study. 359 20

In the onchocerciasis-endemic rain forest area of the Rumpi Hills in southwestern Cameroon, a community-based trial of ivermectin, given either once or twice a year over a three-year period (1988-1991), confirmed that the drug is a potent microfilaricide. The side effects recorded following the first treatment were edema, fever, pruritus, generalized body pains and lymphadenitis. Following subsequent treatments, the same adverse reactions were recorded, but these were generally milder when compared with those of the first treatment. The prevalence of skin microfilaria (mf) was more reduced in zone two, in which treatment was given every six months (76.9% reduction at the end of one year) than in the zone one, in which treatment was given once a year (7.4% reduction). In both zones, the impact of the drug in reducing the intensity of infection was more significant than that for prevalence. Besides pruritus, other skin symptoms were not significantly modified by ivermectin treatment. Ivermectin reduced the prevalence of ocular mf as well as the mf load of the anterior chamber of the eye, resulting in improvement of certain eye lesions such as punctate keratitis, anterior uveitis, and papillary anomalies. There was also some improvement in visual acuity. The level of participation of the village populations was somewhat low, ranging from 52% to 66%, despite excitement over the drug's additional benefit of expelling intestinal round worms.
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PMID:A community-based trial of ivermectin for onchocerciasis control in the forest of southwestern Cameroon: clinical and parasitologic findings after three treatments. 842 94