The VES-Matic 5 system: performance of a novel instrument for measuring erythrocyte sedimentation rate

OBJECTIVES

The VES-Matic 5 is an automated analyzer that assesses erythrocyte sedimentation rate based on a modified Westergren sedimentation technique. Instrument performance was established by addressing the recommendations of the International Council for Standardization in Haematology.

METHODS

Comparison against the reference Westergren method was performed for all samples, and further for the low, middle, and upper third of the analytical range. Intra-run precision, inter-run precision, and interference studies were further assessed. This study included the evaluation of reference ranges.

RESULTS

The comparison of methods by Passing-Bablok analysis has shown a good agreement without systematic or proportional differences. The regression equation was y=-0.646 + 0.979x. The mean bias of -0.542 was obtained by Bland-Altman analysis and the upper limit of 8.03 with the lower limit of -9.11 can be considered clinically acceptable. Intra-run and inter-run precision were good for each parameter and interference studies did not show any significant bias with exception of anemia samples, which showed a proportional difference when comparing high erythrocyte sedimentation rate values. Using the local adult reference population, we verified the reference ranges in comparison to those available in the literature, and according to the Clinical Laboratory Standards Institute (CLSI) EP28-A3C document. We determined the upper limit partitioned by gender and the following age groups: from 18 to 50, from 50 to 70, and over 70.

CONCLUSIONS

The VES-Matic 5 analyzer presented good comparability with the reference method. As there are commercial quality control and suitable external quality assessment (EQA) material and programs, the VES-Matic 5 can be employed appropriately for routine purposes.

OUP accepted manuscript

Objective

To identify the potential prognostic value of lymphocyte subsets in COVID-19 patients, where lymphopenia is a common finding.

Methods

In 353 COVID-19 inpatients and 40 controls T cell subsets with markers of senescence and exhaustion were studied by flow cytometry.

Results

In severe illness, total lymphocytes B, NK, and all T subsets were dampened. Senescent CD4+, but mainly CD8+T cells, increased in patients with respect to controls. The most significant index predicting fatal outcome was neutrophils/CD3+T ratio.

Conclusion

In conclusion, an altered T cell pattern underlies COVID-19 severity and is involved in predicting the outcome.

Reduced muscle mass as predictor of intensive care unit hospitalization in COVID-19 patients

Purpose

To evaluate if reduced muscle mass, assessed with Computed Tomography (CT), is a predictor of intensive care unit (ICU) hospitalization in COVID-19 patients.

Methods

In this Institution Review Board approved study, we retrospectively evaluated COVID-19 patients treated in our tertiary center from March to November 2020 who underwent an unenhanced chest CT scan within three weeks from hospitalization.We recorded the mean Hounsfield Unit (Hu) value of the right paravertebral muscle at the level of the 12^th thoracic vertebra, the hospitalization unit (ICU and COVID-19 wards), clinical symptoms, Barthel Index, and laboratory findings.Logistic regression analysis was applied to assess if muscle loss (Hu<30) is a predictor of ICU admission and outcome.Fisher’s exact and Student’s tests were applied to evaluate if differences between patients with and without muscle loss occurred (p<0.05).

Results

One-hundred-fifty patients matched the inclusion criteria (46 females; mean age±SD 61.3±15 years-old), 36 treated in ICU. Patients in ICU showed significantly lower Hu values (29±24 vs 39.4±12, p = 0.001). Muscle loss was a predictor of ICU admission (p = 0.004).Patients with muscle loss were significantly older (73.4±10 vs 56.4±14 years), had lower Barthel Index scores (54.4±33 vs 85.1±26), red blood-cell count (3.9±1 vs 4.6±1×10¹²L⁻¹), and Hb levels (11.5±2 vs 13.2±2g/l) as well as higher white blood-cell count (9.4±7 vs 7.2±4×10⁹L⁻¹), C-reactive protein (71.5±71 vs 44±48U/L), and lactate dehydrogenase levels (335±163 vs 265.8±116U/L) (p<0.05, each).

Conclusions

Muscle loss seems to be a predictor of ICU hospitalization in COVID-19 patients and radiologists reporting chest CT at admission should note this finding in their reports.

Monocyte distribution width (MDW) parameter as a sepsis indicator in intensive care units

OBJECTIVES

Patients in Intensive Care Units (ICU) are a high-risk population for sepsis, recognized as a major cause of admission and death. The aim of the current study was to evaluate the diagnostic accuracy and prognostication of monocyte distribution width (MDW) in sepsis for patients admitted to ICU.

METHODS

Between January and June 2020, we conducted a prospective observational study during the hospitalization of 506 adult patients admitted to the ICU. MDW was evaluated in 2,367 consecutive samples received for routine complete blood counts (CBC) performed once a day and every day during the study. Sepsis was diagnosed according to Sepsis-3 criteria and patients enrolled were classified in the following groups: no sepsis, sepsis and septic shock.

RESULTS

MDW values were significantly higher in patients with sepsis or septic shock in comparison to those within the no sepsis group [median 26.23 (IQR: 23.48-29.83); 28.97 (IQR: 21.27-37.21); 21.99 (IQR: 19.86-24.36) respectively]. ROC analysis demonstrated that AUC is 0.785 with a sensitivity of 66.88% and specificity of 77.79% at a cut-off point of 24.63. In patients that developed an ICU-acquired sepsis MDW showed an increase from 21.33 [median (IQR: 19.47-21.72)] to 29.19 [median (IQR: 27.46-31.47)]. MDW increase is not affected by the aetiology of sepsis, even in patients with COVID-19. In sepsis survivors a decrease of MDW values were found from the first time to the end of their stay [median from 29.14 (IQR: 26.22-32.52) to 25.67 (IQR: 22.93-30.28)].

CONCLUSIONS

In ICU, MDW enhances the sepsis detection and is related to disease severity.

Validation of a composed COVID-19 chest radiography score: the CARE project

OBJECTIVES

The aim of this study was to validate a composed coronavirus disease 2019 (COVID-19) chest radiography score (CARE) based on the extension of ground-glass opacity (GG) and consolidations (Co), separately assessed, and to investigate its prognostic performance.

METHODS

COVID-19-positive patients referring to our tertiary centre during the first month of the outbreak in our area and with a known outcome were retrospectively evaluated. Each lung was subdivided into three areas and a three-grade score assessing the extension of GG and Co was used. The CARE was derived from the sum of the subscores. A mixed-model ANOVA with post hoc Bonferroni correction was used to evaluate whether differences related to the referring unit (emergency room, COVID-19 wards and intensive care unit (ICU)) occurred. Logistic regression analyses were used to investigate the impact of CARE, patients' age and sex on the outcome. To evaluate the prognostic performance of CARE, receiver operating characteristic curves were computed for the entire stay and at admission only.

RESULTS

A total of 1203 chest radiographs of 175 patients (120 males; mean age 67.81±15.5 years old) were examined. On average, each patient underwent 6.8±10.3 radiographs. Patients in ICU as well as deceased patients showed higher CARE scores (p<0.05, each). Age, Co and CARE significantly influenced the outcome (p<0.05 each). The CARE demonstrated good accuracy (area under the curve (AUC)=0.736) using longitudinal data as well as at admission only (AUC=0.740). A CARE score of 17.5 during hospitalisation showed 75% sensitivity and 69.9% specificity.

CONCLUSIONS

The CARE was demonstrated to be a reliable tool to assess the severity of pulmonary involvement at chest radiography with a good prognostic performance.

An in vitro model to mimic the thrombotic occlusion of small vessels in catastrophic antiphospholipid syndrome (CAPS)

Platelet activation and decrease in platelet count characterize the development of the most feared form of antiphospholipid syndrome (APS), i.e. catastrophic APS (CAPS). We aimed to assess if immuno-affinity purified anti-β2-glycoprotein I (aβ2GPI) antibodies enhance platelet activation inducing a significant flow obstruction in a platelet function analyzer (PFA). Affinity purified aβ2GPI antibodies were obtained from 13 triple positive patients with a strong lupus anticoagulant (LA) and high titers of IgG anticardiolipin antibodies (aCL) and IgG aβ2GPI. Platelet activation stimulated by adenosine diphosphate (ADP) in the presence or absence of aβ2GPI was measured by the expression of P-selectin on platelet surface using flow cytometry. P-selectin expression remained close to baseline when normal whole blood was incubated with aβ2GPI alone. When stimulated using aβ2GPI combined with ADP, P-selectin expression (28.42 ± 5.15% vs. 20.98 ± 3.94%, p = 0.0076) was significantly higher than ADP alone. Closure time of normal whole blood passed through the PFA was significantly shorter using affinity purified aβ2GPI than control IgG both in Col/ADP (160.1 ± 62.1 s vs. 218.6 ± 43.8 s; p = 0.021) and Col/EPI cartridges (149.5 ± 26.7 s vs. 186.9 ± 45.5 s; p = 0.030). Thus, platelet activation is enhanced by aβ2GPI antibodies with a consequent premature closure in a PFA, possibly resembling that in microcirculation in patients with CAPS.

Automated measurement of the erythrocyte sedimentation rate: method validation and comparison

Background

Development of automated analyzers for erythrocyte sedimentation rate (ESR) has imposed the need for extensive validation prior to their implementation in routine practice, to ensure comparability with the reference Westergren method. The aim of our study was to perform the analytical validation of two automated ESR analyzers, the Ves-Matic Cube 200 and the TEST1.

Methods

Validation was performed according to the recent International Council for Standardization in Hematology recommendations and included determination of intrarun and inter-run precision, assessment of sample carryover, hemolysis interference, sensitivity to fibrinogen, method comparison with the gold standard Westergren method and stability test.

Results

The highest intrarun imprecision was obtained for the low ESR range (33.5% for Ves-Matic Cube; 37.3% for TEST1) while inter-run coefficients of variation on three levels were much better for the TEST1 (0%, 2% and 1.2%) compared to the Ves-Matic Cube 200 on two levels (24.9% and 5.8%). Both Ves-Matic Cube 200 and TEST1 showed no statistically significant difference when compared with Westergren. Bland-Altman analysis yielded overall insignificant mean biases for all comparisons, but a wider dispersion of results and 95% limits of agreement for comparisons including the Ves-Matic Cube 200. Carryover was considered insignificant, while hemolysis had a negative effect on all assessed ESR methods. The highest sensitivity to fibrinogen was observed for the Ves-Matic Cube 200, followed by Westergren and the least sensitive was the TEST1.

Conclusions

The obtained results proved the analytical validity of the TEST1 and the Ves-Matic Cube 200, and high comparability with the gold standard Westergren method, showing obvious improvements in standardization of ESR methods.

Ves-Matic CUBE 200: is modified Westergren method for erythrocyte sedimentation rate a valid alternative to the gold standard?

Ves-Matic CUBE 200 is an automated erythrocyte sedimentation rate (ESR) analyser based on the modified Westergren principle of measurement. In this study, we aimed to assess its analytical performance following the key points addressed by the International Council for Standardization in Haematology and the comparability with the gold standard Westergren method. Comparison of the two methods yielded a correlation coefficient of 0.852, no significant bias and a small constant difference between compared results. Intrarun coefficients of variation (CV) ranged from 2.2% to 22.2%, the higher being for lower ESR values, while inter-run CVs were 19.7% for the normal range and 3.0% for the abnormal range. This study proved the analytical validity of the Ves-Matic CUBE 200 and its high comparability with the Westergren method, showing obvious improvements in the technology applied for automated determination of ESR and a valuable step forward in standardisation of ESR methods.

Relevance of pre-analytical blood management on the emerging cardiovascular protein biomarkers TWEAK and HMGB1 and on miRNA serum and plasma profiling

BACKGROUND

Disease-independent sources of biomarker variability include pre-analytical, analytical and biological variance. The aim of the present study was to evaluate whether the pre-analytical phase has any impact on the emerging heart disease TWEAK and HMGB1 protein markers and miRNA biomarkers, and whether peptidome profiling allows the identification of pre-analytical quality markers.

METHODS

An assessment was made of sample type (serum, EDTA-Plasma, Citrate-Plasma, ACD-plasma, Heparin-plasma), temperature of sample storage (room temperature or refrigerated), time of sample storage (0.5, 3, 6 and 9h) and centrifugation (one or two-step). Aliquots of all processed samples were immediately frozen (-80°C) before analysis. Proteins were assayed by ELISAs, miRNA expression profile by microarray and peptidome profiling by MALDI-TOF/MS.

RESULTS

Temperature, time and centrifugation had no impact on TWEAK and HMGB1 results, which were significantly influenced by matrix type, TWEAK levels being significantly higher (F=194.7, p<0.0001), and HMGB1 levels significantly lower (F=36.32, p<0.0001) in serum than in any other plasma type. Unsuitable miRNA results were obtained using Heparin-plasma. Serum miRNA expression profiles depended mainly on temperature, while EDTA-plasma miRNA expression profiles were strongly affected by the centrifugation method used. MALDI-TOF/MS allowed the identification of seven features as indices of pre-analytical serum (m/z at 1206, 1350, 1865 and 2021) or EDTA-plasma (m/z 1897, 2740 and 2917) degradation.

CONCLUSIONS

Serum and EDTA-plasma allow the analysis of both proteins and miRNA emerging biomarkers of heart diseases. Refrigerated storage prevents an altered miRNA expression profile also in cases of a prolonged time-interval between blood drawing and processing.

Computer-based-limited and personalised education management maximise appropriateness of vitamin D, vitamin B12 and folate retesting

Aim

To identify the best management strategy for improving the appropriateness of vitamin D, vitamin B12 and folate retesting.

Methods

The study was conducted between 3 November 2012 and 8 June 2015, with inpatients and outpatients being considered separately. After an observational reference period (3 November 2012 to 14 September 2013), an information technology (IT)-based permissive strategy (16 September 2013 to 27 July 2014) followed by a limiting strategy was used to manage the demand for inpatient retesting. For outpatients, an educational strategy period (28 July 2014 to 16 December 2014) with direct contact between medical personnel and general practitioners (GPs) was followed by a post-educational period without any restriction. Data from a total of 66 496 patients for vitamin D, 14 618 for vitamin B12 and 14 445 for folate were retrieved from the laboratory IT system. The main outcomes measures were inappropriate vitamin D, vitamin B12 and folate retesting. The minimal retesting intervals were 90 (vitamin D) or 180 days (vitamin B12 and folate).

Results

In the absence of a laboratory demand strategy, the frequency of inappropriate retesting for vitamin D, vitamin B12 and folate was 60%, 94% and 93%, respectively, for inpatients, and 27%, 87% and 87%, respectively, for outpatients. A limiting IT-based demand management strategy reduced inappropriate retesting for vitamin D (36%), but not for vitamin B12 and folate. The educational strategy was followed by a reduction in inappropriate retesting among outpatients (16% for vitamin D, 72% for vitamin B12 and folate).

Conclusions

Laboratory demand management based on an IT-limiting management strategy or on education of the referring physicians appears helpful in maximising appropriate retesting.

Performance criteria and quality indicators for the post-analytical phase

Quality indicators (QIs) used as performance measurements are an effective tool in accurately estimating quality, identifying problems that may need to be addressed, and monitoring the processes over time. In Laboratory Medicine, QIs should cover all steps of the testing process, as error studies have confirmed that most errors occur in the pre- and post-analytical phase of testing. Aim of the present study is to provide preliminary results on QIs and related performance criteria in the post-analytical phase.

This work was conducted according to a previously described study design based on the voluntary participation of clinical laboratories in the project on QIs of the Working Group “Laboratory Errors and Patient Safety” (WG-LEPS) of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC).

Overall, data collected highlighted an improvement or stability in performances over time for all reported indicators thus demonstrating that the use of QIs is effective in the quality improvement strategy. Moreover, QIs data are an important source for defining the state-of-the-art concerning the error rate in the total testing process. The definition of performance specifications based on the state-of-the-art, as suggested by consensus documents, is a valuable benchmark point in evaluating the performance of each laboratory.

Laboratory tests play a relevant role in the monitoring and evaluation of the efficacy of patient outcome thus assisting clinicians in decision-making. Laboratory performance evaluation is therefore crucial to providing patients with safe, effective and efficient care.

A Randomized Trial of Pharmacogenetic Warfarin Dosing in Naïve Patients with Non-Valvular Atrial Fibrillation

Genotype-guided warfarin dosing have been proposed to improve patient’s management. This study is aimed to determine whether a CYP2C9- VKORC1- CYP4F2-based pharmacogenetic algorithm is superior to a standard, clinically adopted, pharmacodynamic method. Two-hundred naïve patients with non-valvular atrial fibrillation were randomized to trial arms and 180 completed the study. No significant differences were found in the number of out-of-range INRs (INR<2.0 or >3.0) (p = 0.79) and in the mean percentage of time spent in the therapeutic range (TTR) after 19 days in the pharmacogenetic (51.9%) and in the control arm (53.2%, p = 0.71). The percentage of time spent at INR>4.0 was significantly lower in the pharmacogenetic (0.7%) than in the control arm (1.8%) (p = 0.02). Genotype-guided warfarin dosing is not superior in overall anticoagulation control when compared to accurate clinical standard of care.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01178034.

TNFA Haplotype Genetic Testing Improves HLA in Estimating the Risk of Celiac Disease in Children

Background

TNF-α and IFN-γ play a role in the development of mucosal damage in celiac disease (CD). Polymorphisms of TNFA and IFNG genes, as well as of the TNFRSF1A gene, encoding the TNF-α receptor 1, might underlie different inter-individual disease susceptibility over a common HLA risk background. The aims of this study were to ascertain whether five SNPs in the TNFA promoter (-1031T>C,-857C>T,-376G>A,-308G>A,-238G>A), sequence variants of the TNFRSF1A gene and IFNG +874A>T polymorphism are associated with CD in a HLA independent manner.

Methods

511 children (244 CD, 267 controls) were genotyped for HLA, TNFA and INFG (Real Time PCR). TNFRSF1A variants were studied (DHPLC and sequence).

Results

Only the rare TNFA-1031C (OR=0.65, 95% CI:0.44-0.95), -857T (OR=0.42, 95% CI:0.27-0.65), -376A (OR=2.25, 95% CI:1.12-4.51) and -308A (OR=4.76, 95% CI:3.12-7.26) alleles were significantly associated with CD. One TNFRSF1A variant was identified (c.625+10A>G, rs1800693), but not associated with CD. The CD-correlated TNFA SNPs resulted in six haplotypes. Two haplotypes were control-associated (CCGG and TTGG) and three were CD-associated (CCAG, TCGA and CCGA). The seventeen inferred haplotype combinations were grouped (A to E) based on their frequencies among CD. Binary logistic regression analysis documented a strong association between CD and HLA (OR for intermediate risk haplotypes=178; 95% CI:24-1317; OR for high risk haplotypes=2752; 95% CI:287-26387), but also an HLA-independent correlation between CD and TNFA haplotype combination groups. The CD risk for patients carrying an intermediate risk HLA haplotype could be sub-stratified by TNFA haplotype combinations.

Conclusion

TNFA promoter haplotypes associate with CD independently from HLA. We suggest that their evaluation might enhance the accuracy in estimating the CD genetic risk.

Performance criteria and quality indicators for the pre-analytical phase

The definition, implementation and monitoring of valuable analytical quality specifications have played a fundamental role in improving the quality of laboratory services and reducing the rates of analytical errors. However, a body of evidence has been accumulated on the relevance of the extra-analytical phases, namely the pre-analytical steps, their vulnerability and impact on the overall quality of the laboratory information. The identification and establishment of valueable quality indicators (QIs) represents a promising strategy for collecting data on quality in the total testing process (TTP) and, particularly, for detecting any mistakes made in the individual steps of the pre-analytical phase, thus providing useful information for quality improvement projects. The consensus achieved on the developed list of harmonized QIs is a premise for the further step: the identification of achievable and realistic performance targets based on the knowledge of the state-of-the-art. Data collected by several clinical laboratories worldwide allow the classification of performances for available QIs into three levels: optimum, desirable and minimum, in agreement with the widely accepted proposal for analytical quality specifications.

Inflammation and pancreatic cancer: molecular and functional interactions between S100A8, S100A9, NT-S100A8 and TGFβ1

BACKGROUND

In order to gain further insight on the crosstalk between pancreatic cancer (PDAC) and stromal cells, we investigated interactions occurring between TGFβ1 and the inflammatory proteins S100A8, S100A9 and NT-S100A8, a PDAC-associated S100A8 derived peptide, in cell signaling, intracellular calcium (Cai2+) and epithelial to mesenchymal transition (EMT). NF-κB, Akt and mTOR pathways, Cai2+ and EMT were studied in well (Capan1 and BxPC3) and poorly differentiated (Panc1 and MiaPaCa2) cell lines.

RESULTS

NT-S100A8, one of the low molecular weight N-terminal peptides from S100A8 to be released by PDAC-derived proteases, shared many effects on NF-κB, Akt and mTOR signaling with S100A8, but mainly with TGFβ1. The chief effects of S100A8, S100A9 and NT-S100A8 were to inhibit NF-κB and stimulate mTOR; the molecules inhibited Akt in Smad4-expressing, while stimulated Akt in Smad4 negative cells. By restoring Smad4 expression in BxPC3 and silencing it in MiaPaCa2, S100A8 and NT-S100A8 were shown to inhibit NF-κB and Akt in the presence of an intact TGFβ1 canonical signaling pathway. TGFβ1 counteracted S100A8, S100A9 and NT-S100A8 effects in Smad4 expressing, not in Smad4 negative cells, while it synergized with NT-S100A8 in altering Cai2+ and stimulating PDAC cell growth. The effects of TGFβ1 on both EMT (increased Twist and decreased N-Cadherin expression) and Cai2+ were antagonized by S100A9, which formed heterodimers with TGFβ1 (MALDI-TOF/MS and co-immuno-precipitation).

CONCLUSIONS

The effects of S100A8 and S100A9 on PDAC cell signaling appear to be cell-type and context dependent. NT-S100A8 mimics the effects of TGFβ1 on cell signaling, and the formation of complexes between TGFβ1 with S100A9 appears to be the molecular mechanism underlying the reciprocal antagonism of these molecules on cell signaling, Cai2+ and EMT.

Pancreatic tumors and immature immunosuppressive myeloid cells in blood and spleen: role of inhibitory co-stimulatory molecules PDL1 and CTLA4. An in vivo and in vitro study

BACKGROUND

Blood and spleen expansion of immature myeloid cells (IMCs) might compromise the immune response to cancer. We studied in vivo circulating and splenic T lymphocyte and IMC subsets in patients with benign and malignant pancreatic diseases. We ascertained in vitro whether pancreatic adenocarcinoma (PDAC)-associated IMC subsets are induced by tumor-derived soluble factors and whether they are immunosuppressive focusing on the inhibitory co-stimulatory molecules PDL1 and CTLA4.

METHODOLOGY AND PRINCIPAL FINDINGS

103 pancreatic and/or splenic surgical patients were enrolled including 52 PDAC, 10 borderline and 10 neuroendocrine tumors (NETs). Lymphocytes and IMCs were analysed by flow cytometry in blood, in spleen and in three PDAC cell conditioned (CM) or non conditioned PBMC. PDL1 and CTLA4 were studied in 30 splenic samples, in control and conditioned PBMC. IMCs were FACS sorted and co-coltured with allogenic T lymphocytes. In PDAC a reduction was found in circulating CD8(+) lymphocytes (p = 0.004) and dendritic cells (p = 0.01), which were reduced in vitro by one PDAC CM (Capan1; p = 0.03). Blood myeloid derived suppressive cells (MDSCs) CD33(+)CD14(-)HLA-DR(-) were increased in PDAC (p = 0.022) and were induced in vitro by BxPC3 CM. Splenic dendritic cells had a higher PDL1 expression (p = 0.007), while CD33(+)CD14(+)HLA-DR(-) IMCs had a lower CTLA4 expression (p = 0.029) in PDAC patients. In vitro S100A8/A9 complex, one of the possible inflammatory mediators of immune suppression in PDAC, induced PDL1 (p = 0.018) and reduced CTLA4 expression (p = 0.028) among IMCs. IMCs not expressing CTLA4 were demonstrated to be immune suppressive.

CONCLUSION

In PDAC circulating dendritic and cytotoxic T cells are reduced, while MDSCs are increased and this might favour tumoral growth and progression. The reduced CTLA4 expression found among splenic IMCs of PDAC patients was demonstrated to characterize an immune suppressive phenotype and to be consequent to the direct exposure of myeloid cells to pancreatic cancer derived products, S100A8/A9 complex in particular.

New screening tests enrich anti-transglutaminase results and support a highly sensitive two-test based strategy for celiac disease diagnosis

BACKGROUND

The identification of specific serological algorithms allowing the diagnosis of celiac disease (CD) is a new challenge for both the clinic and the laboratory. We compared the diagnostic accuracy of three new tests proposed for CD screening with that of the well established IgA tTG, and ascertained whether any combination of these tools might enhance accuracy in diagnosing CD.

METHODS

In sera from 329 CD and 374 control children, the following were assayed: IgA tTG; IgA/IgG, which identify tTG-gliadin complexes (Aeskulisa Celi Check and CeliCheck IgGA); IgA/IgG, which identify deamidated gliadin peptides and tTG (QUANTA Lite(TM) h-tTG/DGP Screen).

RESULTS

When specificity was set at 100%, the most sensitive index of CD was IgA tTG (75.7%, cut-off=100U), followed by QUANTA Lite(TM) h-tTG/DGP Screen (65.3%, cut-off 145U), Aeskulisa Celi Check (62.6%, cut-off 909U/mL) and CeliCheck IgGA (59.6%, cut-off 977U/mL). Three algorithms were obtained by combining IgA tTG with each of the new tests. The algorithm obtained by measuring IgA tTG and QUANTA Lite(TM) h-tTG/DGP Screen allowed the correct identification of CD in 78.7% of cases (negative predictive value=97.3%).

CONCLUSIONS

The two-test based strategy could be used for the cost effective diagnosis of CD.

VKORC1, CYP2C9 and CYP4F2 genetic-based algorithm for warfarin dosing: an Italian retrospective study

Aim: A total of 371 patients under stable warfarin therapy were retrospectively selected to develop a pharmacogenetic algorithm to identify the individual maintenance dose. Materials & methods: The variables that were entered into the algorithm were: VKORC1, CYP2C9 and CYP4F2 polymorphisms, body surface area and age. Results: The percentage of cases whose predicted mean weekly warfarin dose was within 20% of the actual maintenance dose was 51.8% considering patients overall, and were 36.2, 66.2 and 55.4%, respectively, taking into account patients requiring low (≤25 mg/week), intermediate (25–45 mg/week) and high (≥45 mg/week) doses. The algorithm could correctly assign 73.8 and 63.2% of patients to the low- and high-dose regimens, respectively. We developed and validated a pharmacogenetic algorithm in a series of Italian patients, we then tested, in the same series of italian patients, the formulas of three published algorithms. These three algorithms were developed and validated by their authors in a series of patients different from our own. The performance of our algorithm in our patients series was slightly higher than that achieved when using the three other algorithms in our patients series. Conclusion: The high predictive accuracy of low and high warfarin requirements of our algorithm warrants its application in prospective studies for clinical validation.

Serum thyroid hormone concentrations and weight loss relationships in eight obese women during semistarvation

Eight obese female patients were studied over a period of 15 days whilst on 300 kcal diet. Serum levels of thyroxine and free throxine index were not altered significantly by semistarvation. A TRH test performed before and after the diet showed no appreciable change. Weight loss was intially rapid but later slowed despite good patients compliance. Serum concentrations of T 3 and reverse T 3 (rT3) early decreased (p less than 0.01) and increased (p less than 0.05) respectively, but returned towards control levels even before discontinuation of semistarvation. There was a positive correlation between the percentage decrease in body weight and the percentage increase in serum rT 3 (p less than 0.001), and a negative correlation between decrease in body weight and decrease in serum T 3 (p less than 0.001). Our results do not suggest that the variations in serum triiodothyronines limit the weight loss; it is probable, on the contrary, that the weight loss promotes the observed variations in thyroid hormones by as yet unknown adaptive metabolic forces.

[Carbohydrate metabolism in gross obesity]

Results obtained in an investigation of two groups of obese and grossly obese subjects are presented. Poorer carbohydrate tolerance was noted in the latter. Blood insulin patterns after oral glucose loading, however, were less easy to interpret. Overall, the values were much the same in the two groups. Nevertheless, analysis of the curves showed that the grossly obese displayed a later peak.

Glucose tolerance in jejunoileal bypass for morbid obesity: a fifteen month follow-up

Twelve patients with body weight varying from 106 to 163 Kg, underwent jejunoileal bypass operations; their oral glucose tolerance tests (oGTT) were evaluated before the operation and one, five, and fifteen months afterwards. The lowering of the glycemic curve and the decrease of the insulinemia values during oGTT have been studied in relation to intestinal absorption deficit and weight loss. It is concluded that weight loss was the main factor determining the improvement of glucose metabolism.

[Physiopathological correlations between carbohydrate and lipid metabolicm and obesity]

Sugar and fat metabolism were studied in a group of obese women without diabetes. Blood triglicerides and cholesterol were, on average, within normal limits, though endogenous hypertriglyceridaemia was noted in a few cases. Triglycerides were significantly related to blood sugar (baseline and after glucose loading), whereas there was no significant connection with blood insulin. The meaning of these results is discussed.