How to Estimate the Cost of Point-of-Care CD4 Testing in Program Settings: An Example Using the Alere Pima™ Analyzer in South Africa

Integrating POC CD4 testing technologies into HIV counseling and testing (HCT) programs may improve post-HIV testing linkage to care and treatment. As evaluations of these technologies in program settings continue, estimates of the costs of POC CD4 tests to the service provider will be needed and estimates have begun to be reported. Without a consistent and transparent methodology, estimates of the cost per CD4 test using POC technologies are likely to be difficult to compare and may lead to erroneous conclusions about costs and cost-effectiveness. This paper provides a step-by-step approach for estimating the cost per CD4 test from a provider's perspective. As an example, the approach is applied to one specific POC technology, the Pima™ Analyzer. The costing approach is illustrated with data from a mobile HCT program in Gauteng Province of South Africa. For this program, the cost per test in 2010 was estimated at $23.76 (material costs =$8.70; labor cost per test = $7.33; and equipment, insurance, and daily quality control =$7.72). Labor and equipment costs can vary widely depending on how the program operates and the number of CD4 tests completed over time. Additional costs not included in the above analysis, for on-going training, supervision, and quality control, are likely to increase further the cost per test. The main contribution of this paper is to outline a methodology for estimating the costs of incorporating POC CD4 testing technologies into an HCT program. The details of the program setting matter significantly for the cost estimate, so that such details should be clearly documented to improve the consistency, transparency, and comparability of cost estimates

Avaliação da adsorção de tetraciclina em adsorvente convencional e modificado com cloreto de ferro, sulfato de cobre e peróxido de hidrogênio : análise regenerativa e aplicação em matriz aquosa real

A tetraciclina (TC) é uma droga lícita amplamente utilizada no âmbito farmacêutico. Considerada um indicador de contaminação antropogênica, é de grande interesse o estudo de técnicas eficazes para sua remoção. O processo de adsorção pode ser considerado um tratamento complementar ao tratamento convencional de água e efluentes. Nesse contexto, o presente trabalho tem como objetivo determinar as condições operacionais ótimas e o mecanismo de adsorção para a remoção de TC, utilizando sólido adsorvente convencional (CA) e modificado por cloreto de ferro (CAFe), sulfato de cobre (CA-Cu) e peróxido de hidrogênio (CA-H2O2), além de avaliar suas aplicações em matriz aquosa sintética e real e diferentes técnicas de regeneração. Na adsorção em batelada foram avaliadas as influências do pH (2 – 10), concentração de adsorvente (5 – 80 g.L-1) e tempo de contato (5 – 300 min). Foi realizada a investigação da cinética, do equilíbrio e da termodinâmica de adsorção. Analisaram-se a influência da temperatura, o tipo de solvente e o tempo de sonificação, respectivamente, para os três métodos regenerantes do sólido adsorvente – térmico, químico e ultrassônico. Para avaliar o tratamento com matriz aquosa real, a caracterização da carga poluidora e detecção de tetraciclina foram realizadas antes e após o processo de adsorção. Por fim, para confirmar suas propriedades, os materiais adsorventes foram caracterizados com análises de pHPCZ, MEV, DRX, FTIR e isotermas de adsorção/dessorção de N2. Os resultados mostraram que as condições ótimas de adsorção de TC para o sólido convencional são pH 4,0, tempo de retenção de 120 minutos e dosagem de adsorvente de 30 g.L-1. Os sólidos modificados se destacam, uma vez que não foi necessária a realização do ajuste de pH, apresentaram uma cinética inicial mais rápida e proporcionaram uma redução de no mínimo 50% de massa de adsorvente (15, 10 e 5 g.L-1 para CA-H2O2, CA-Fe e CA-Cu, respectivamente) necessária para a adsorção da tetraciclina, comparado com o sólido sem tratamento. Além disso, apresentaram uma maior área superficial e volume de mesoporos e não comprometeram a estrutura do material após a modificação. O modelo de pseudossegunda ordem foi o que melhor representou a cinética de adsorção do fármaco estudado. A isoterma de Redlich-Peterson descreveu o equilíbrio da TC nas três temperaturas, para todos os sólidos adsorventes. O estudo termodinâmico indicou que a adsorção foi espontânea, favorável e endotérmica. O tratamento com matriz aquosa real confirmou que a etapa de coagulação/floculação não consegue remover por completo a tetraciclina. Por fim, na etapa regenerativa, a eficiência de regeneração alcançou valores acima de 85%. Entre as três técnicas empregadas, o tratamento térmico a 200 °C foi selecionado como o agente regenerativo ótimo para o estudo, apresentando uma capacidade regenerativa de 90% até o sexto ciclo. De forma geral, este trabalho apresenta grande potencial em termos de remoção do micropoluente emergente tetraciclina, tanto em matriz aquosa sintética como real além uma possibilidade eficaz de regeneração e reutilização do sólido adsorvente saturado, minimizando resíduos e custos de tratamento.Tetracycline (TC) is a licit drug widely used in the pharmaceutical field. Considered an indicator of anthropogenic contamination, it is of great interest to study effective techniques for its removal. The adsorption process can be considered as a complementary treatment to conventional water and wastewater treatment. In this context, the present work aims to determine the optimal operating conditions and the adsorption mechanism for the removal of tetracycline drug (TC) using conventional adsorbent solid (CA) and modified by iron chloride (CA-Fe), copper sulfate (CA-Cu) and hydrogen peroxide (CA-H2O2), besides evaluating their applications in real aqueous matrix and different regeneration techniques. In batch adsorption the influences of pH (2 - 10), concentration of adsorbent (5 - 80 g.L-1) and contact time (5 - 300 min) were evaluated. The kinetics, equilibrium and adsorption thermodynamics were investigated. The influence of temperature, type of solvent and sonification time, respectively, were analyzed for the three regenerative methods of the adsorbent solid - thermal, chemical and ultrasonic. To evaluate the treatment with real aqueous matrix, the characterization of the pollutant charge and tetracycline detection were performed before and after the adsorption process. Finally, to confirm their properties, the adsorbent materials were characterized with pHPCZ, SEM, XRD, FTIR and N2 adsorption/desorption isotherms. The results showed that the optimum TC adsorption conditions for the conventional solid are at pH 4.0, retention time of 120 minutes and adsorbent dosage of 30 g.L-1. The modified solids stand out as no pH adjustment was required, had a faster initial kinetics and provided a minimum of 50% reduction in adsorbent mass (15, 10 and 5 gL-1 for CA-H2O2, CA-Fe and CA-Cu, respectively) for tetracycline adsorption compared to the untreated solid. Moreover, they presented a larger surface area and volume of mesoporous and did not compromise the material structure after modification. The pseudo-second order model best represented the adsorption kinetics of the studied drug. The Redlich-Peterson isotherm described the equilibrium of TC at all three temperatures for all adsorbent solids. The thermodynamic study indicated that the adsorption was spontaneous and favorable, besides increasing with the temperature increase. The actual aqueous matrix treatment confirmed that the coagulation/flocculation step cannot completely remove tetracycline. Finally, in the regenerative stage, the regeneration efficiency reached values above 85%. Among the three techniques employed, heat treatment at 200 ° C was selected as the optimal regenerative agent for the study, with a regenerative capacity of 90% until the sixth cycle. In general, this work has great potential in terms of removal of the emerging micro-pollutant tetracycline, both in synthetic and real aqueous matrix and an effective possibility of regeneration and reuse of saturated adsorbent solid, minimizing waste/treatment costs

Evaluation of different POCT devices for glucose measurement in a clinical neonatal setting.

Hypoglycaemia is a major cause of neonatal morbidity and may induce long-term developmental sequelae. Clinical signs of hypoglycaemia in neonatal infants are unspecific or even absent, and therefore, precise and accurate methods for the assessment of glycaemia are needed. Glycaemia measurement in newborns has some particularities like a very low limit of normal glucose concentration compared to adults and a large range of normal haematocrit values. Many bedside point-of-care testing (POCT) systems are available, but literature about their accuracy in newborn infants is scarce and not very convincing. In this retrospective study, we identified over a 1-year study period 1,324 paired glycaemia results, one obtained at bedside with one of three different POCT systems (Elite? XL, Ascensia? Contour? and ABL 735) and the other in the central laboratory of the hospital with the hexokinase reference method. All three POCT systems tended to overestimate glycaemia values, and none of them fulfilled the ISO 15197 accuracy criteria. The Elite XL appeared to be more appropriate than Contour to detect hypoglycaemia, however with a low specificity. Contour additionally showed an important inaccuracy with increasing haematocrit. The bench analyzer ABL 735 was the most accurate of the three tested POCT systems. Both of the tested handheld glucometers have important drawbacks in their use as screening tools for hypoglycaemia in newborn infants. ABL 735 could be a valuable alternative, but the blood volume needed is more than 15 times higher than for handheld glucometers. Before daily use in the newborn population, careful clinical evaluation of each new POCT system for glucose measurement is of utmost importance