“Background: Malaria rapid diagnostic tests (RDTs) are now


“Background: Malaria rapid diagnostic tests (RDTs) are now widely used for prompt on-site diagnosis in remote endemic areas where reliable microscopy is absent. Aberrant results, whereby negative test results occur at high parasite densities, have been variously reported for over a decade and have led to questions regarding the reliability of the tests in clinical use.\n\nMethods: PF-3084014 In the first trial, serial dilutions of recombinant HRP2 antigen were tested on an HRP2-detectiing RDT. In a second trial, serial dilutions of culture-derived Plasmodium falciparum parasites were tested against three HRP2detecting RDTs.\n\nResults: A prozone-like effect occurred in RDTs at a high concentration

of the target antigen, histidine-rich protein-2 (above 15,000 ng/ml), a level that corresponds to more than 312000 Protein Tyrosine Kinase inhibitor parasites per mu L. Similar results were noted on three RDT products using dilutions of cultured parasites up to a parasite density of 25%. While reduced line intensity was observed, no false negative results occurred.\n\nConclusions: These results suggest that false-negative malaria RDT results will rarely occur due to a prozone-like effect in high-density infections, and other causes are more likely. However, RDT line intensity is poorly indicative of parasite density in high-density infections and RDTs should, therefore, not be considered quantitative. Immediate management

of suspected severe malaria should rely on clinical assessment or microscopy. Evaluation against high concentrations of antigen should be considered BMS-754807 inhibitor in malaria RDT product development and lot-release testing, to ensure that very weak or false negative results will not occur at antigen concentrations that might be seen clinically.”
“Electrical impedance tomography (EIT) is a non-invasive, radiation-free functional imaging technique, which

allows continuous bedside measurement of regional lung ventilation. Pneumothorax is an uncommon but nevertheless potentially dangerous incident that may arise unexpectedly. We report an incident of an accidental tension pneumothorax during an experimental ventilation study in a pig that was continuously monitored by EIT. The early sign of the occurring pneumothorax, prior to all clinical signs, was a fast increase of end-expiratory impedance in the ventral part of the right lung indicating that non-ventilated air entered this part, followed by a disappearance of ventilation in this region. At the same time the ventilation-related impedance changes of the left lung remained almost unchanged. The pneumothorax onset was localized using a newly introduced pneumothorax dynamics map directly derived from dynamic EIT data. We conclude that non-invasive EIT may be helpful as a tool to detect the development of a pneumothorax, which could be of particular interest during invasive procedures such as insertion of a central venous catheter.

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