Open AccessCirculatory histidine levels as predictive indicators of disease activity in takayasu arteritis
Author(s) -
Kumar Umesh,
Mehta Pankti,
Kumar Sandeep,
Jain Avinash,
Guleria Anupam,
Kumar R Venkatesh,
Misra Ramnath,
Kumar Dinesh
Publication year - 2021
Publication title -
analytical science advances
Language(s) - English
Resource type - Journals
ISSN - 2628-5452
DOI - 10.1002/ansa.202000181
Subject(s) - interquartile range , receiver operating characteristic , medicine , histidine , gastroenterology , analysis of variance , arteritis , circulatory system , chemistry , biochemistry , enzyme
Background and objective Quantitative assessment of disease activity is important for effective management of patients with autoimmune inflammatory diseases (AIDs) including Takayasu arteritis (TA). Histidine supplementation alleviates inflammation and has strong anti‐oxidative effects as well. The present study aims to evaluate the diagnostic potential of circulatory histidine for predicting disease activity in TA. Methods The serum metabolic profiles on 98 TA‐patients and 77 normal controls (NC) samples were measured at high‐resolution 800 MHz NMR spectrometer employing standard 1D‐ 1 H‐CPMG NMR experiments. The NMR spectral data were processed and concentrations of histidine and other circulatory metabolites were estimated with respect to formate (as an internal reference) and compared using ANOVA based on Tukey's multiple comparison test and statistical significance was considered at P ‐value < 0.05. The correlations of histidine with plasma CRP and ESR levels were evaluated using Spearman‐ r method. Data were expressed as median (interquartile‐range [IQR]). Results Histidine levels were significantly decreased in active TA patients (23.90; IQR:16.10) compared to both inactive TA patients (35.50, IQR:24.30) and NC (42.80, IQR:22.10), whereas there was no significant difference between inactive TA and NC. For TA patients, the histidine levels correlated negatively with clinical markers of inflammation, that is, ESR ( r = ‐0.19, P < .078) and with the CRP ( r = ‐0.26, P < .013). Further, the receiver‐operating‐characteristic (ROC) curve analysis was performed to test the diagnostic potential of histidine for differentiating active from inactive disease. The area under the ROC curve (AUROC) value equal to 0.65 [95% CI = 0.54‐0.76] revealed its moderate discriminatory ability. Compared to other circulatory metabolites, the discriminatory performance of histidine was also found to be in the moderate range (highest AUROC‐value of 0.76 was found for glutamine‐to‐glucose ratio (QGR). Conclusion The study demonstrated the altered circulatory histidine levels in TA patients that may serve as a surrogate marker for improving the diagnostic screening of active and inactive TA patients.