White blood cell count: a valuable tool for suspecting Cushing's syndrome.

PURPOSE: Simple screening tests to determine whether Cushing's syndrome (CS) should be ruled out are lacking. Tools that enable early diagnosis could reduce morbidity and associated sequelae. The potential of glucocorticoid-induced changes in the white blood cell (WBC) count for raising suspicion of CS is assessed. METHODS: This was a retrospective case‒control study. The WBC counts of 73 cases with CS and 146 matched controls were compared. The number of leukocytes (Leu), the number and percentage of neutrophils (N, Np), the number and percentage of lymphocytes (L, Lp), neutrophil-to-lymphocyte differences in the number and percentage (N-L, Np-Lp), neutrophil-to-lymphocyte ratio in the number and percentage (NLR, NLRp), and leukocyte-to-lymphocyte differences (Leu-L) were evaluated. The area under the ROC curve (AUC) was calculated for each of these parameters. Reference values were estimated that could help disclose occult CS. RESULTS: All ten parameters showed significant differences between cases and controls. The AUC was greater than 0.7 for all ten parameters, and was the best for the NLRp and Lp (AUC: 0.89). An Lp of 23.9% showed a diagnostic accuracy of 84.9% for the diagnosis of CS. The concordance of an Lp below 24% and more than 8000 leucocytes had a PPV of 78.2% for CS, while the pairing of an Lp over 24% and a Leu below 8000 cells had an NPV of 97.3% for CS. CONCLUSION: WBC count assessment can be an effective tool to raise suspicion of CS, prompting diagnostic testing. This simple and universally available test may allow earlier diagnosis of CS before highly evolved phenotypes develop.

Vertical cutoff methods in serum protein electrophoresis for the measurement of monoclonal protein concentrations: Which is best?

BACKGROUND: Monoclonal protein (M-protein) concentrations are measured by serum protein electrophoresis (SPE). Two methods are used for demarcating the M-protein area in the electropherogram: perpendicular drop (PD) and tangent skimming (TS). The aim of this study was tocompare both methods and to establish which is the most accurate and precise. METHODS: We studied 24 sera containing M-protein (5-44 g/L). The systematic error (SE) was evaluated in a dilution series of 12 sera. Within-day, between-day, and interobserver variability were assessed. SPE was performed by capillary and agarose gel electrophoresis. M-protein concentrations were measured using both cutoff methods. RESULTS: The PD method shows a constant SE ranged 1.00-2.27 g/L, while constant SE for TS is ranged -0.30--0.57 g/L. None of the cutoff methods or electrophoretic methods showed a proportional SE, with the exception of the TS method in capillary electrophoresis for ß-migrating M-protein. The PD method was more precise than the TS method in all three estimates of imprecision. An increased CV for concentrations < 10 g/L in between-day imprecision was observed with the TS method. Interobserver imprecision was greater for M-protein concentrations < 17 g/L for both cutoff methods (14.85%, 26.42% respectively). CONCLUSIONS: Despite being less precise, the TS method provides a more accurate measurement of M-protein concentration.

Estudio de la ferropenia en el laboratorio clínico / Laboratory evaluation of iron deficiency

El hierro es un elemento químico esencial para todos los organismos vivos, necesario para un amplio espectro de funciones metabólicas vitales. La exploración del metabolismo del hierro puede ser difícil en algunas situaciones, tales como en el paciente con una enfermedad crónica, por la respuesta de los biomarcadores frente a la inflamación. En los últimos años el laboratorio clínico ha incorporado nuevos biomarcadores a los tradicionalmente empleados, con el fin de mejorar su contribución al diagnóstico y seguimiento de la ferropenia. Se ha realizado una búsqueda sistemática de la evidencia científica publicada en los diez últimos años para los siguientes biomarcadores: el diagnóstico morfológico de la sangre periférica, los índices hematimétricos, y las concentraciones plasmáticas de transferrina (y sus índices), ferritina, receptor soluble de transferrina y hemoglobina, en la ferropenia. Se emiten recomendaciones para estos biomarcadores en relación al diagnóstico y manejo del paciente ferropénico

Iron is an essential chemical element for all living organisms, and is required for a broad spectrum of vital metabolic functions. The study of iron metabolism can be challenging in some situations, such as in patients with chronic diseases, due to the effect of inflammation response. In recent years, clinical laboratory research has introduced new biomarkers to those commonly used, with the aim of improving the diagnosis and management of iron deficiency. In this work, a systematic search of the scientific evidence reported during the last decade has been made for the following biomarkers: morphological diagnosis of peripheral blood, hematimetric indices, and plasma concentrations of transferrin (and its indices), ferritin, transferrin receptor, and haemoglobin, in iron deficiency. Recommendations are made for these biomarkers related to the diagnosis and management of the iron-deficient patient

Assessment of Kidney Graft Function Evolution Measured by Creatinine and Cystatin C.

INTRODUCTION: The 2013 Kidney Disease Outcomes Quality Initiative Clinical Practice Guideline suggests measuring cystatin C (sCys) in adults with glomerular filtration rate (GFR) based on creatinine (sCr) between 45 and 59 mL/min/1.73 m2 if confirmation of chronic kidney disease (CKD) is required. There is not enough evidence to recommend the use of sCys or sCr to estimate GFR in kidney transplant recipients. OBJECTIVES: Our aims were to describe the evolution of sCr, sCys, and GFR in a group of kidney transplant patients and to determine their association with some markers of morbidity at 1 year. METHODS: A total of 54 patients were included. Analytical and clinical data were recorded. Renal function was analyzed using the CKD Epidemiology Collaboration (EPI) sCr equation and CKD-EPI sCys equation. RESULTS: sCys-estimated GFR was higher than estimated from sCr by CKD-EPI. The values of sCys have more variability than those of sCr. The agreement between the stages of CKD by sCr or sCys-estimated GFR measured by Cohen's kappa coefficient was only fair. One-year CKD-associated variables correlated differently with sCr and sCys-estimated GFR. Hemoglobin, uric acid, calcium, and phosphorus related to sCr-estimated GFR, whereas serum albumin was associated with sCys-estimated GFR. CONCLUSIONS: sCys values have a higher variability than sCr in kidney transplant recipients. sCys- or sCr-based GFRs have a nonsimilar behavior in these patients with weak agreement to stratify CKD stages and a different relationship to CKD-related comorbid conditions.