[Leucocyte esterase as a reliable diagnostic, cost-effective and fast in knee infections]. / Esterasa leucocitaria como prueba diagnóstica eficaz, económica y rápida ante un proceso infeccioso articular de rodilla.

BACKGROUND: The articular infection represents a challenge due to its complexity and its devastating effect when not treated promptly. We have various diagnostic studies: cultures, ESR, CRP, count of leukocytes, among others but none is specific, it takes more than 30 minutes to complete and require complex infrastructure. In this study we determine the sensitivity and specificity of the leukocyte esterase for detection of an infectious process joint in Mexican population. MATERIAL AND METHODS: From November 2015 to April 2016 was obtained synovial fluid from patients with diagnosis of knee infection with or without implant and without infection with degenerative pathology of the knee. It assessed the sample through the COMBI-SCREEN 11SYS leukocyte esterase with reading colorimetric test at two minutes determining positive for infection: two crosses, the remainder of the sample was sent to culture. RESULTS: We perform the test in 64 samples of synovial fluid of knee joint 19 diagnosed with infection and 45 without infection. Was obtained a sensitivity 100%, specificity of 88.24%, PPV 68.42% and PNV 100%, kappa index 0.753 using the program IBM SPSS Statistics 22, Python ver. 2.7. CONCLUSIONS: Leukocyte esterase is a fast, economical and effective to detect an infectious process against one inflammatory with high probability of success. This study showed an index of concordance 0.753 Kappa, proving to be reproducible so recommend be implemented in the emergency department at the national level.

ANTECEDENTES: La infección articular es un reto ortopédico por la complejidad diagnóstica y sus efectos devastadores al no tratarse oportunamente. Se cuenta con diversos estudios de diagnóstico: cultivo, VSG, PCR, conteo de leucocitos, entre otros, pero ninguno es preciso, tardan más de 30 minutos en realizarse y requieren una infraestructura compleja. En este estudio se determina la sensibilidad y especificidad de la esterasa leucocitaria para la detección de un proceso infeccioso articular en población mexicana. MATERIAL Y MÉTODOS: de Noviembre de 2015 a Abril de 2016 se obtuvo líquido sinovial de pacientes con diagnóstico de infección articular con o sin implante y sin infección con patología degenerativa de rodilla. Se evaluó la muestra mediante el test de esterasa leucocitaria COMBI-SCREEN 11SYS con lectura colorimétrica a los dos minutos, determinando positivo para infección: dos cruces, el resto de la muestra fue enviado a cultivo. RESULTADOS: Se aplicó el test a 64 muestras de líquido sinovial de rodilla, 19 diagnosticadas con infección articular y 45 sin infección. Se obtuvo una sensibilidad 100%, especificidad 88.24% VPP 68.42% y VPN 100%, índice de concordancia kappa 0.753 mediante el programa IBM SPSS Statistics 22, Python versión 2.7. CONCLUSIONES: La esterasa leucocitaria es una prueba rápida, económica y eficaz para detectar un proceso infeccioso contra un proceso inflamatorio con alta probabilidad de acierto. Este estudio presentó un índice de concordancia kappa de 0.753, demostrando ser reproducible, por lo que se recomienda implementarse en los servicios de urgencias a nivel nacional.

Esterasa leucocitaria como prueba diagnóstica eficaz, económica y rápida ante un proceso infeccioso articular de rodilla / Leucocyte esterase as a reliable diagnostic, cost-effective and fast in knee infections

Resumen: Antecedentes: La infección articular es un reto ortopédico por la complejidad diagnóstica y sus efectos devastadores al no tratarse oportunamente. Se cuenta con diversos estudios de diagnóstico: cultivo, VSG, PCR, conteo de leucocitos, entre otros, pero ninguno es preciso, tardan más de 30 minutos en realizarse y requieren una infraestructura compleja. En este estudio se determina la sensibilidad y especificidad de la esterasa leucocitaria para la detección de un proceso infeccioso articular en población mexicana. Material y métodos: de Noviembre de 2015 a Abril de 2016 se obtuvo líquido sinovial de pacientes con diagnóstico de infección articular con o sin implante y sin infección con patología degenerativa de rodilla. Se evaluó la muestra mediante el test de esterasa leucocitaria COMBI-SCREEN 11SYS con lectura colorimétrica a los dos minutos, determinando positivo para infección: dos cruces, el resto de la muestra fue enviado a cultivo. Resultados: Se aplicó el test a 64 muestras de líquido sinovial de rodilla, 19 diagnosticadas con infección articular y 45 sin infección. Se obtuvo una sensibilidad 100%, especificidad 88.24% VPP 68.42% y VPN 100%, índice de concordancia kappa 0.753 mediante el programa IBM SPSS Statistics 22, Python versión 2.7. Conclusiones: La esterasa leucocitaria es una prueba rápida, económica y eficaz para detectar un proceso infeccioso contra un proceso inflamatorio con alta probabilidad de acierto. Este estudio presentó un índice de concordancia kappa de 0.753, demostrando ser reproducible, por lo que se recomienda implementarse en los servicios de urgencias a nivel nacional.

Abstract: Background: The articular infection represents a challenge due to its complexity and its devastating effect when not treated promptly. We have various diagnostic studies: cultures, ESR, CRP, count of leukocytes, among others but none is specific, it takes more than 30 minutes to complete and require complex infrastructure. In this study we determine the sensitivity and specificity of the leukocyte esterase for detection of an infectious process joint in Mexican population. Material and methods: From November 2015 to April 2016 was obtained synovial fluid from patients with diagnosis of knee infection with or without implant and without infection with degenerative pathology of the knee. It assessed the sample through the COMBI-SCREEN 11SYS leukocyte esterase with reading colorimetric test at two minutes determining positive for infection: two crosses, the remainder of the sample was sent to culture. Results: We perform the test in 64 samples of synovial fluid of knee joint 19 diagnosed with infection and 45 without infection. Was obtained a sensitivity 100%, specificity of 88.24%, PPV 68.42% and PNV 100%, kappa index 0.753 using the program IBM SPSS Statistics 22, Python ver. 2.7. Conclusions: Leukocyte esterase is a fast, economical and effective to detect an infectious process against one inflammatory with high probability of success. This study showed an index of concordance 0.753 Kappa, proving to be reproducible so recommend be implemented in the emergency department at the national level.

Is there yet any place for reagent strips in diagnosing spontaneous bacterial peritonitis in cirrhotic patients? An accuracy and cost-effectiveness study in Brazil.

BACKGROUND: Diagnosis of spontaneous bacterial peritonitis (SBP) is currently based on ascitic cell counting, but there is a need for a more simple and rapid diagnostic tool. The objectives of this study are to evaluate the accuracy of reagent strips in diagnosing SBP and compare their costs with total and differential cell counts. PATIENTS AND METHODS: 71 cirrhotic in- and outpatients were consecutively included (159 samples). Spontaneous bacterial peritonitis was defined as neutrophil cells >or= 250/microL. The cutoff values for each reagent strip were defined by a receiver operating characteristic (ROC) curve. Sensitivity (S), Specificity (Sp), Positive and Negative Predictive Values (PPV and NPV), Accuracy (Ac) and cost-effectiveness (US$) in comparison to cell count exam were calculated. RESULTS: Spontaneous bacterial peritonitis was diagnosed in 17 patients (23.9%), 11 of them with positive culture (64.7%). The best cutoff points found in ROC curves were 1+ for Multistix 10 SG and ca. 75 for Choiceline 10 (Multistix 10 SG S = 80%, Sp = 98.5%, PPV = 90.9%, NPV = 96.2%, Ac = 95%; Choiceline 10 S = 76.9%, Sp = 97.7%, PPV = 87%, NPV = 95.6%, Ac = 94%). In terms of cost-effectiveness by cost/accuracy, cell count was 41.5, Multistix 10 SG 0.57, and Choiceline 10, 0.19 (P < 0.001). CONCLUSION: Reagent strips are a useful tool for diagnosing SBP in cirrhotic patients, but they have some limitations. Strips are especially indicated when total and differential cell counts are not quickly available or sometimes unavailable. They are also indicated as screening test in emergency rooms to anticipate the diagnosis of SBP and allow its early treatment. It's an interesting option in developing countries.

Assessment of monocytic component in acute myelomonocytic and monocytic/monoblastic leukemias by a chemiluminescent assay.

INTRODUCTION: Classically, the monocytic component of acute myelomonocytic (FAB-M4) and acute monocytic/monoblastic (FAB-M5) leukemias is demonstrated by nonspecific esterase positivity in cytochemical stainings. We have previously demonstrated that non-specific esterases from normal monocytes can be determined by a chemiluminescent method. In the present study, we investigated whether this assay can also determine the monocytic component of FAB-M4 and FAB-M5 and distinguish these acute myeloid leukemia (AML) categories. MATERIALS AND METHODS: Bone marrow samples were obtained from 66 patients with AML (M0, two cases; M1, 12 cases; M2, 13 cases; M3, 10 cases; M4, 11 cases; M5, 12 cases; M6, two cases; M7, four cases). Cells were incubated with a standard reaction mixture and chemiluminescence was measured for 10 min. Two parameters were assessed, the peak (PLE) and the integrated light emission (ILE). RESULTS: Both PLE and ILE were higher in FAB-M4 and FAB-M5 subtypes compared to other AML subtypes (P<0.001). In addition, the classification of AML cases into FAB-M4, FAB-M5 and nonmonocytic subtypes based on ILE analysis was concordant with alpha-naphthyl acetate esterase (ANAE) in 97% of cases (kappa coefficient 0.94, P<0.001). CONCLUSIONS: These findings indicate that this chemiluminescent assay was able to determine the monocytic component of FAB-M4 and FAB-M5 cells, and the classification of AML subtypes based on chemiluminescent analysis strongly agreed with the cytochemical ANAE-staining. In conclusion, this chemiluminescent assay is a simple, fast and objective method, which may be useful as an alternative tool in the differential diagnosis of AML subtypes.

Towards a cost effective strategy for cutinase production by a recombinant Saccharomyces cerevisiae: strain physiological aspects.

Although the physiology and metabolism of the growth of yeast strains has been extensively studied, many questions remain unanswered where the induced production of a recombinant protein is concerned. This work addresses the production of a Fusarium solani pisi cutinase by a recombinant Saccharomyces cerevisiae strain induced through the use of a galactose promoter. The strain is able to metabolise the inducer, galactose, which is a much more expensive carbon source than glucose. Both the transport of galactose into the cell-required for the induction of cutinase production-and galactose metabolism are highly repressed by glucose. Different fermentation strategies were tested and the culture behaviour was interpreted in view of the strain metabolism and physiology. A fed-batch fermentation with a mixed feed of glucose and galactose was carried out, during which simultaneous consumption of both hexoses was achieved, as long as the glucose concentration in the medium did not exceed 0.20 g/l. The costs, in terms of hexoses, incurred with this fermentation strategy were reduced to 23% of those resulting from a fermentation carried out using a more conventional strategy, namely a fed-batch fermentation with a feed of galactose.

Cytochemical staining and flow cytometry methods applied to the diagnosis of acute leukemia in the pediatric population: an assessment of relative usefulness.

BACKGROUND: Cytochemical staining has been used in the diagnosis of acute leukemia for more than 20 years. The general availability of flow cytometers and an extensive panel of antibody reagents useful for characterizing blood cell lineage question the usefulness of continuing routine use of the cytochemical staining for the diagnosis of acute leukemia. PATIENTS AND METHODS: Test results were evaluated in 122 (n = 122; 112 with acute lymphocytic leukemia and 10 with acute myeloid leukemia) patients selected from among 320 patients with acute leukemia at Texas Children's Hospital in 1997 and 1998. Results were selected for review if the clinical encounter represented the initial diagnostic work-up and if data were available from cytochemical staining and flow cytometry studies. RESULTS: Cell lineage classification derived from flow cytometry and cytochemical stains were in agreement in all cases. Definitive diagnoses were feasible using flow cytometry results alone in 120 of 122 patients (98.4%) as compared with only 99 of 122 patients (81.2%) when only cytochemical staining results were considered. In two patients with inconclusive flow cytometry results, cytochemical staining alone provided information sufficient for diagnosis. CONCLUSIONS: Results from this study indicate that with few exceptions, flow cytometry studies alone provide sufficient information for diagnosis and management of acute leukemia in children. Nevertheless, cytochemical staining should be available for those cases in which flow cytometry results fail to allow a definitive diagnosis. A modified testing protocol is recommended.

Simultaneous subtyping of group specific component and esterase D by isoelectric focusing on agarose gels.

A quick, sensitive and economical technique has been developed to subtype GC and ESD simultaneously on the same agarose IEF gel. This method could be a useful tool for forensic application.

The slide centrifuge gram stain as a urine screening method.

A slide centrifuge Gram stain procedure was performed to screen for bacteriuria 4161 urine specimens submitted in urine preservative tubes for routine culture. For slide centrifuge Gram staining, each urine sample was mixed well. Thereafter, 0.2 mL of each sample was placed, using a pipette, into a slide centrifuge chamber and centrifuged at 2,000 rpm for 5 minutes. The slides were heat fixed, Gram stained, and read by laboratory personnel who scanned 12 consecutive oil-immersion fields using a set pattern. The presence of the same organism in six or more fields was defined as a positive urine screen. Urine samples were cultured using a 0.001-mL loop and a comparison of culture growth with slide centrifuge screening was made. When growth of 100,000 or more colony-forming units per milliliter (CFU/mL) was the reference for comparison, the screen had a sensitivity rate of 98%, a specificity rate of 90%, a negative predictive value of 99%, and a positive predictive value of 65%. When a lower colony count of 10,000 or more CFU/mL was the reference for comparison, the screen had a sensitivity rate of 88%, a specificity rate of 95%, a negative predictive value of 96%, and a positive predictive value of 84%. The slide centrifuge Gram stain is a very sensitive screening method to detect bacteriuria in an adult male population.

[Assessment of cholesterol esterase activity in the duodenal contents of man]. / Opredelenie aktivnosti kholesterolésterazy v duodenal'nom soderzhimom cheloveka.

In 20 healthy patients the cholesterol esterase activity in duodenal content was examined. The cholesterol ether of o-coumaric acid was used as a substrate. Increase of the cholesterol esterase activity was noted after stimulation of pancreozymin and secretin. The cholesterol esterase concentration in duodenal content changes in more wide range than the index of the output. The cholesterol esterase output is the most significant informative index. There is not any cholesterol esterase activity in bile, gastric juice and saliva. The results obtained have shown that the main part of the estimated cholesterol esterase activity has a pancreatic base. The investigation of the cholesterol esterase activity in duodenal content may be used in the study of the exocrine function of pancreas.

An acute and subacute neurotoxicity assessment of trichlorfon.

The toxicity of trichlorfon (O,O-dimethyl-2,2,2,-trichloro-1-hydroxyethylphosphonate, Dipterex, Dylox), reported to elicit delayed neurotoxicity in man and chickens, was studied by administering single subcutaneous doses of 100 or 300 mg/kg to adult White Leghorn hens. At 24 h posttreatment, the birds were observed for visible signs of neurotoxicity, were euthanized, and samples of blood plasma, brain, and spinal cord (cervical and thoracic regions) were obtained for quantification of cholinesterase and neurotoxic esterase (NTE) activities. In subacute studies, hens were dosed with trichlorfon (100 mg/kg) every 72 h for a total of six doses. Seventy-two hours after the final dose the hens were euthanized, the brains, spinal cords, and distal sciatic nerves were removed for enzymatic and (or) histological examination. Parallel acute and subacute studies were conducted using diisopropyl phosphorofluoridate (DFP), a known neurotoxic agent, at subcutaneous dosages of 1.0 mg/kg. In the acute studies, both DFP and trichlorfon markedly inhibited tissue cholinesterase activities but only DFP elicited a significant inhibition of NTE. In the subacute studies, DFP produced a characteristic central-peripheral distal axonopathy in the 18-day period of study which was confirmed by clinical and morphological evidence and by marked inhibition of neuronal NTE. Trichlorfon caused little or no obvious neurotoxicity, an observation that was supported by minimal morphological changes and impairment of walking ability and no inhibition of brain or spinal cord NTE.

Assessment of the delayed neurotoxic potential of isopropyl triphenylphosphate using a nontraditional testing strategy.

The potential of isopropyl triphenyl phosphate (ITP) to produce delayed neurotoxicity in hens was examined using several techniques. ITP contained O,O,O-triphenyl phosphate (24%), O-o-isopropylphenyl O,O-diphenyl phosphate (25%), O,O-diisopropyl-phenyl O-phenyl phosphate (20%), O-o, p-diisopropylphenyl O,O-diphenyl phosphate (18%) and O-p-isopropylphenyl O,O-diphenyl phosphate (6%). Hens treated twice, 3 wk apart, with doses of ITP as high as 11.7 g/kg showed no clinical signs of delayed neurotoxicity and only mild signs of general toxicity. Furthermore, none showed even subtle neurohistologic changes suggestive of delayed neurotoxicity. ITP produced dose-dependent inhibition of hen plasma cholinesterase and brain neurotoxic esterase (NTE). The study was continued because NTE inhibition has been shown to be a reliable predictor of organophosphates that produce delayed neurotoxicity. ITP was administered prior to tri-o-tolyl phosphate (TOCP) challenge in order to determine if it altered development of TOCP delayed neurotoxicity. ITP neither enhanced nor reduced the onset or severity of neurotoxicity produced by TOCP. The time-course for brain and spinal cord NTE inhibition by ITP and TOCP were compared and found to be different. The maximum brain NTE inhibition produced by ITP (doses up to 11.7 g/kg) was never complete (always less than 90%), and spinal cord NTE inhibition was significantly less than that produced in the brain. In contrast, brain and spinal cord inhibition produced by 500 mg TOCP/kg were equal and greater than 90%. This testing regimen showed that ITP produced an effect on NTE at the biochemical level without producing clinical or neurohistologic abnormalities in treated hens. Furthermore, this biochemical effect was qualitatively different than that produced by the delayed neurotoxicant TOCP.