ABSTRACT
BACKGROUND: A single midnight serum cortisol (MSC) test has been reported to possess the best sensitivity and specificity for diagnosing Cushing's syndrome (CS). However, this test requires patient hospitalization, making it costly. This paper aims to compare the hospital budget impact and accuracy of using midnight salivary cortisol (MSVC), as opposed to MSC, in the diagnosis of hypercortisolism. METHODS: 77 patients with at least two high urinary free cortisol (UFC) values (>360 nmol/24 h) were selected from 611 patients with clinical symptoms of CS. The costs of the method to confirm the diagnosis of hypercortisolism was calculated comparing Option A using MSC (UFCx2, low-dose dexamethasone suppression test [LDDST]) that requires patient hospitalization versus Option B using MSVC (UFCx2, LDDST) in which the evaluation is done outside the Hospital. A budget impact analysis for one year was developed, and a sensitivity analysis in different scenarios was performed. Reproducibility and diagnostic performance of MSVC and MSC were also measured. RESULTS: Salivary cortisol is a sound analytical method for evaluating free serum cortisol due to its classification accuracy, good imprecision, linearity, and stability. AUC(ROC) comparison between MSVC and MSC shows no significant differences. The substitution of the MSC for MSVC in our hospital could save between 16,762 and 132,804 in one year. CONCLUSIONS: The use of MSVC in the diagnosis of hypercortisolism can result in a substantial decrease in the budget impact, without losing diagnosis accuracy and reliability, a significant advantage considering the current emphasis on reducing the financial burden of health care.
Subject(s)
Budgets , Cushing Syndrome/diagnosis , Hydrocortisone/analysis , Saliva/chemistry , Female , Hospital Costs , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Introducción. Los auto-anticuerpos son marcadores útiles en el inicio de la diabetes mellitus autoinmune, como apoyo diagnóstico. El objetivo de este trabajo fue conocer la prevalencia de autoanticuerpos en el inicio de diabetes en nuestro medio, medidos mediante ELISA y valorar su papel diagnóstico en diabetes autoinmune. Material y métodos. Muestra de 111 pacientes con diabetes de inicio: 61 tipo 1 (incluye 12 diabetes autoinmune latente del adulto [LADA]) y 50 tipo 2. Grupo control 64 no diabéticos. Se analizaron antidescarboxilasa del ácido glutámico GADA, anti-tirosina fosfatasa de membrana IA-2 y anti-insulina IAA, mediante enzimoinmunoanálisis ELISA en microplaca. Se realizó estudio observacional descriptivo para valoración de pruebas diagnósticas. Programa estadístico PASW Statistics versión 18. Resultados. GADA(+): 78,7% DM1; 83,3% LADA; 2,0% DM2; 1,6% control. IA-2(+): 52,2% DM1; 45,5% LADA; 16,4% DM2; 12,5% control. IAA(+): 10,3% DM1; 18% LADA; 6,0% DM2; 1,7% control. GADA e IA-2 diferenciaron significativamente (p<0,0001) a los pacientes con diabetes autoinmune. No así IAA. Área bajo curva receiver operating characteristics (ROC): GADA=0,90 (p<0,0001); IA-2=0,74 (p<0,0001); IAA=0,57 (p=0,126). Criterio límite GADA(+) > 5,5 U/mL (sensibilidad 79%, especificidad 98%) e IA-2(+) > 6,0 U/mL (sensibilidad 54%, especificidad 84%). Análisis de factores riesgo asociados: Odds ratio GADA=51,44 e IA-2=4,64. Conclusiones. En nuestro estudio, la prevalencia de GADA en el inicio de diabetes es alta y su determinación eficaz en el diagnóstico de diabetes autoinmune. IA-2 incrementó 4,6 veces la probabilidad diagnóstica. IAA medidos mediante nuestro test ELISA no han mostrado valor como marcadores en la diabetes autoinmune, aunque esto no descarta su utilidad en otras patologías (AU)
Autoantibodies are useful markers for clinical onset of autoimmune diabetes, and as a diagnostic supports. The aim of this study was to determine the prevalence of autoantibodies at the onset diabetes mellitus in our environment, measured by an ELISA technique, and to assess its role as autoimmune diabetes diagnostic support. Material and methods. A sample of 111 patients with diabetes onset was studied, which included, 61 type 1 diabetes (12 Latent Autoimmune Diabetes in Adults (LADA) and 50 type 2 diabetes. Control group: 64 non-diabetics. Antibodies glutamic acid decarboxylase antibodies (GADA), membrane phosphatase anti-tyrosine (IA-2), and anti-insulin (IAA) were determined by enzyme immunoassay ELISA microplates. A descriptive observational study was conducted to the measure diagnostic tests using the software PASW Statistics version 18. Results. GADA(+): 78.7% DM1; 2.0% DM2; 1.6% control. IA-2(+): 52.2% DM1; 45.5% LADA; 16.4% DM2; 12.5% control. IAA(+): 10.3% DM1; 18.0% LADA; 6.0% DM2; 1.7% control. Comparing means, autoimmune diabetics were significantly differentiated (P<.0001) by GADA and IA-2 values, but not with IAA. The area under the Curve using software Receiver Operating Characteristics (ROC): GADA=0.90 (P<.0001), IA-2=0.74 (P<.0001), IAA=0.57 (P=.126). Optimal cut off for GADA>5.5U/mL (sensitivity 79%, specificity 98%) and IA-2>6.0U/mL (sensitivity 54%, specificity 84%). On analysing risk factors associated with autoimmune diabetes diagnosis, the calculated Odds ratio gave GADA=51.44 and IA-2=4.64. Conclusions. In this study GADA(+) prevalence is high at diabetes onset, and its calculation has been effective for autoimmune diabetes diagnosis. IA-2 increases diagnostic probability 4.6 times. Anti-insulin antibodies measured by ELISA test did not demonstrate value for autoimmune diabetes diagnosis and classification, although its usefulness is not excluded for the diagnosis support of other diseases (AU)
