Response of children with Plasmodium falciparum to chloroquine and development of a national malaria treatment policy in Zaire

In vivo sensitivity of Plasmodium falciparum to chloroquine was evaluated in 4 of 9 regions of Zaire in 1985 to develop a national strategy for treatment of malaria. Children less than 5 years of age were treated with either a single dose of chloroquine base, 10 mg/kg, or a dose of 25 mg/kg given over 3 d. A modified 7-day World Health Organization in vivo test was used with follow-up 2, 3 and 7 d after the start of treatment. 339 children were studied. In Bwamanda 92% of children were aparasitaemic 7 days after chloroquine, 10 mg/kg, but in Kinshasa only 44% were free of parasites after 25 mg/kg chloroquine. The mean drop in parasite density among those who did not clear parasites by day 7 was greater than 98% of the initial value. Although the parasite density decreased markedly, the failure of most subjects to become aparasitaemic indicated a marked decrease in parasite sensitivity since 1983. Only one child of 51 who were initially febrile remained febrile, although 14 (28%) of these had resistant parasites. The decrease in parasitaemia and temperature, even among children with resistant strains, led the Ministry of Health to recommend 25 mg/kg chloroquine as first line treatment for fever/malaria in their national malaria control plan. The plan includes drug sensitivity surveillance and a referral system for patients who do not respond to chloroquine treatment.     

ACUTE PSYCHOSIS ASSOCIATED WITH ABRUPT WITHDRAWAL OF CARBAMAZEPINE FOLLOWING INTOXICATION

SUMMARY Carbamazepine is regularly used in the treatment of trigeminal neuralgia. Although exacerbation of psychosis has been described following abrupt discontinuation of carbamazepine in chronic schizophrenics, a withdrawal syndrome has not been reported previously in patients treated for trigeminal neuralgia. The case presented here suggests that abrupt withdrawal of toxic concentrations of carbamazepine may precipitate a withdrawal reaction, which is manifest some days after discontinuation of the drug. Therefore it may be advisable to withdraw therapy slowly in these situations.     

Mechanisms of cocaine-induced sensitization

Sorg, Barbara A. and Jeffery D. Steketee: Mechanisms of Cocaine-Induced Sensitization. Prog. Neuro-Psychopharmacol. & Biol. Psychiat. 1992, 16(6): 1003–1012.

1. 1. Rats pretreated with repeated footshock demonstrated an augmentation in cocaineinduced locomotor activity and extracellular dopamine concentrations in the nucleus accumbens.

2. 2. Pertussis toxin injections into the A10 region also led to cocaine- induced enhancement in extracellular dopamine levels in the nucleus accumbens and a strong trend towards elevated locomotor activity.

3. 3. Repeated treatment with cocaine led to a blockade of the footshock-induced increase in extracellular dopamine in the medial prefrontal cortex.

4. 4. Prior treatment with pertussis toxin microinjection into the A10 region resulted in enhanced levels of tissue dopamine metabolites in the medial prefrontal cortex following footshock stress.

5. 5. The pertussis toxin- and daily stress-induced behavioral and neurochemical sensitization suggest that behavioral sensitization to these stimuli involves a loss of inhibitory tone on A10 dopamine cells.

Babesiosis in Wisconsin. A new focus of disease transmission

A confirmed case of human babesiosis was identified in August 1983 in a 54-year-old asplenic Wisconsin resident. Babesia microti was identified as the causative agent by blood smear morphology and hamster inoculation techniques. The patient's wife had clinically confirmed Lyme disease in 1981 and had serologic evidence (immunofluorescent antibody to a B microti titer of 1:1,024) of recent Babesia infection in August 1983. Mice (Peromyscus species) trapped on the patients' property and elsewhere in their Wisconsin county of residence were infected with B microti. Lyme disease and babesiosis have the same tick vector and animal reservoir; serum samples from 116 Wisconsin and Minnesota residents with clinically confirmed Lyme disease between 1980 and 1983 were tested, and none were found to have concurrent Babesia infection. This area of Wisconsin is identified as a new focus for babesiosis transmission, but the risk of transmission seems to be low.     

Temporomandibular joint arthrography: comparison of morbidity with ionic and low osmolality contrast media

We compared patient morbidity associated with temporomandibular joint (TMJ) arthrography using both meglumine/sodium diatrizoate (60%) and the new monoacidic dimer, Hexabrix, in a double-blind randomized clinical trial in 31 patients. Patients experienced maximal discomfort from TMJ arthrography with the initial joint filling and joint distension; this rapidly resolved over 10 minutes. Delayed exacerbation of pain is less than described for shoulder arthrography. The newer contrast media promise to decrease patient morbidity with arthrography.     

Field application of a colorimetric method of assaying chloroquine and desethylchloroquine in urine

In a study in western Kenya of malaria-infected adult women who had been treated with chloroquine, we compared the level of chloroquine and its principal metabolite, desethylchloroquine, in urine, measured using a newly developed modified Haskins test, with the level of chloroquine in whole blood, determined by high-performance liquid chromatography. Over a 28-day follow-up period, 277 matched urine and blood samples from 81 women were evaluated. A high correlation was observed between the level of chloroquine in whole blood (in μg/l) and that of chloroquine + desethylchloroquine in urine (in mg/l). The test was easily performed and may be useful for monitoring use of chloroquine in a community and determining pre-study or post-treatment ingestion or absorption of the drug in in vivo studies of parasite sensitivity.