Microsatellite characterization of Plasmodium falciparum from cerebral and uncomplicated malaria patients in southern Vietnam

If parasite genotype influences the clinical course of malaria, we expect that isolates from patients with similar pathology would be more closely related than would be expected by chance. To explore this prediction, we typed nine microsatellite markers in sympatric Plasmodium falciparum isolates from cerebral and uncomplicated malaria patients from Vietnam. Temporal structure and linkage disequilibrium were also examined in this data set.     

The internal medicine subinternship: a curriculum needs assessment

Despite broad acceptance of the internal medicine subinternship rotation by the undergraduate medical education community, only a small fraction of programs provide students with explicit learning objectives. To design a curriculum for the medical subinternship, we surveyed 3 different groups of educational stakeholders--subinternship directors, residency program directors, and housestaff--in order to identify and prioritize the competencies that should be learned during this rotation. This study provides a starting point for the development of a structured curriculum for the fourth-year subinternship rotation.     

Bilateral near-infrared monitoring of the cerebral concentration and oxygen-saturation of hemoglobin during right unilateral electro-convulsive therapy

Reductions in right prefrontal cerebral blood flow have been correlated with symptomatic improvement in depressed individuals receiving electroconvulsive therapy (ECT). Non-invasive near infrared spectroscopy has previously been shown to reliably measure changes in cerebral hemoglobin concentrations and oxygen saturation. In this study, we measured the concentration and oxygen saturation of hemoglobin on the right and left frontal brain regions of nine patients during right unilateral ECT. In all patients, we have found that the electrically induced seizure causes a stronger cerebral deoxygenation on the side ipsilateral to the electrical current (-21+/-5%) with respect to the contralateral side (-6+/-4%). On the brain side ipsilateral to the ECT electrical discharge, we have consistently observed a discharge-induced decrease in the total hemoglobin concentration, i.e. in the cerebral blood volume, by -7+/-3 microM, as opposed to an average increase by 6+/-3 microM on the contralateral side. The ipsilateral decrease in blood volume is assigned to a vascular constriction associated with the electrical discharge, as indicated by the observed decrease in cerebral oxy-hemoglobin concentration and minimal change in deoxy-hemoglobin concentration during the electrical discharge on the side of the discharge. These findings provide indications about the cerebral hemodynamic/metabolic mechanisms associated with ECT, and may lead to useful parameters to predict the individual clinical outcome of ECT.     

Molecular assessment of drug resistance in Plasmodium falciparum from Bahr El Gazal province, Sudan

AIMS: To assess resistance to chloroquine (CQ) and sulphadoxine/pyrimethamine (SP) in a Sudanese parasite population. METHODS: Recurrent security problems in Akuem, Sudan, prevented us from conducting a classical in vivo treatment efficacy study. Instead we genotyped key mutations in the chloroquine resistance transporter (pfcrt), the multidrug resistance gene (pfmdr1), dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps). We genotyped the K76T mutation in pfcrt and the N86Y mutation in (pfmdr) by restriction digestion of fluorescent end-labelled polymerase chain reaction (PCR) products, while we genotyped codons 16, 51, 59, 108 and 164 in dhfr and codons 436, 437, 540, 581 and 613 in dhps by primer extension in 100 blood samples. RESULTS: Sixty-three percent of parasites carried the 76T mutation at pfcrt critical for CQ resistance, while 31% carried the 86Y mutation at pfmdr that is associated with, although not essential, for CQ resistance. We found five dhfr alleles: 60% of infections contained wild-type dhfr alleles, 3% had one mutation, 34% had two mutations, while 3% had three mutations. We found three dhps alleles: 47% were wild type, 44% had one mutation, while 9% had two mutations. CONCLUSIONS: We expect high levels of treatment failure (RI-RIII) with CQ (20-40%) and predict efficient treatment with SP. However, dhfr alleles with three mutations (51I, 59R, 108N) are present as are dhps alleles with two mutations (437G, 540E). Successful treatment with SP is therefore likely to be short-lived.     

Relapsed and late-onset Nipah encephalitis

An outbreak of infection with the Nipah virus, a novel paramyxovirus, occurred among pig farmers between September 1998 and June 1999 in Malaysia, involving 265 patients with 105 fatalities. This is a follow-up study 24 months after the outbreak. Twelve survivors (7.5%) of acute encephalitis had recurrent neurological disease (relapsed encephalitis). Of those who initially had acute nonencephalitic or asymptomatic infection, 10 patients (3.4%) had late-onset encephalitis. The mean interval between the first neurological episode and the time of initial infection was 8.4 months. Three patients had a second neurological episode. The onset of the relapsed or late-onset encephalitis was usually acute. Common clinical features were fever, headache, seizures, and focal neurological signs. Four of the 22 relapsed and late-onset encephalitis patients (18%) died. Magnetic resonance imaging typically showed patchy areas of confluent cortical lesions. Serial single-photon emission computed tomography showed the evolution of focal hyperperfusion to hypoperfusion in the corresponding areas. Necropsy of 2 patients showed changes of focal encephalitis with positive immunolocalization for Nipah virus antigens but no evidence of perivenous demyelination. We concluded that a unique relapsing and remitting encephalitis or late-onset encephalitis may result as a complication of persistent Nipah virus infection in the central nervous system.     

Prominent pruritic periumbilical papules: allergic contact dermatitis to nickel

We report a case series of 38 children with suspected allergic contact dermatitis (ACD) to nickel who presented with prominent subumbilical and periumbilical papules and a generalized, lichenoid papular dermatitis resembling an id reaction. We speculated that this was an ACD to nickel and performed patch tests in 9 (24%) of these patients. All 9 (100%) patients had positive patch test results for nickel, thus confirming the diagnosis.     

Will new human papillomavirus diagnostics improve cervical cancer control efforts?

With the causal link between specific types of human papillomavirus (HPV) and cervical cancer firmly established, efforts have turned to assessing the relative merits of offering HPV testing in screening, triage, and posttreatment management. Many unanswered questions remain, but a growing body of evidence supports a role for HPV testing in cervical cancer prevention programs. Already, clinical centers that serve thousands of women in Europe and the United States have incorporated HPV DNA tests in triage algorithms.