Tuberculosis (TB) is a chronic respiratory infectious disease caused by
The association between MLR and risk of mycobacterial infections has been first reported in rabbits in the 1920s by Florence Sabin and colleagues [
A total of 151 patients with active TB and 129 healthy controls were included into the study. Patients combined with other pathogen infection were excluded. All patients’ information was collected from the clinical data of The Fifth People’s Hospital of Taiyuan between March 1, 2017, and September 1, 2018. Healthy controls were selected from people of physical examination in Shanxi Provincial People’s Hospital. The study was approved by the ethical committee of the Fifth People’s Hospital of Taiyuan.
All inpatients were diagnosed and treated in accordance with Chinese Guidelines on the Diagnosis and Treatment of tuberculosis. Discharge criteria includes the following: negative sputum smear for acid-fast bacilli, negative culture for sputum mycobacterium, chest X-rays improved, absorption of pleural effusion, the erythrocyte sedimentation depressing, or enlarged lymph nodes shrinking.
EDTA blood specimens of all patients were collected at the first day of admission and discharge. Leukocyte differential counts were performed by standard procedures on a Sysmex automated hematology analyzer. The MLR was calculated as the quotient of the absolute monocyte and lymphocyte counts.
All quantitative data were presented using median and interquartile range. A nonparametric Wilcoxon matched pairs test was used to compare the variables before treatment and after treatment in TB patients. The Mann–Whitney
A total of 151 patients with active TB were included into the study. They were all inpatients diagnosed with pulmonary TB, intestinal TB, pelvic TB, TB peritonitis, and TB pleurisy from the Fifth People’s Hospital of Taiyuan between March 1, 2017, and September 1, 2018. The mean age of the 151 patients was 36 ± 16.58 years, and 91 (60%) were male. The average hospitalization time was 39.93 ± 13.19 days. The healthy control group consisted of 75 males and 54 females, with an overall mean age of 38 ± 11.7 years. There was no significant difference in age (
We measured peripheral WBC counts in TB patients before treatment and on discharge to assess the variation of WBC subpopulations. As shown in Figure
Comparison of the WBC absolute count in patients and healthy control: (a) leukocytes; (b) neutrophils; (c) lymphocytes; (d) monocytes. Data are presented with the boxplot graph reporting the median and the interquartile rang (
We calculated the ratio of monocytes to lymphocytes to evaluate the impact of active TB disease and anti-TB therapy on the MLR. The MLR of patients before treatment was 0.45 (IQR: 0.28–0.67), which was higher significantly than healthy controls (0.20, IQR: 0.17–0.25) (
We divided patients into different groups by gender, age, and TB location to assess the change of MLR between before treatment and on discharge. As shown in Table
MLR of patients before treatment and on discharge in different subgroups.
|
Before treatment | On discharge |
|
|
---|---|---|---|---|
Gender | ||||
Male | 90 | 0.50 (0.32–0.69) | 0.35 (0.26–0.54) | <0.001 |
Female | 61 | 0.37 (0.24–0.62) | 0.30 (0.20–0.39) | <0.001 |
Age | <0.001 | |||
<30 y | 75 | 0.47 (0.28–0.69) | 0.32 (0.26–0.46) | <0.001 |
30–55 y | 46 | 0.38 (0.25–0.61) | 0.29 (0.21–0.41) | <0.001 |
>55 y | 30 | 0.47 (0.32–0.77) | 0.35 (0.23–0.59) | <0.001 |
Location | <0.001 | |||
Pulmonary TB | 120 | 0.44 (0.26–0.45) | 0.32 (0.25–0.45) | <0.001 |
Extrapulmonary TB | 31 | 0.49 (0.27–0.77) | 0.37 (0.24–0.48) | 0.001 |
Interactions between mycobacterium and host immune system resulted in the outcome of tuberculosis [
Naranbhai et al. found that MLR could predict the risk of developing tuberculosis during follow-up by analyzing the peripheral blood cells of 1,336 South African infants aged 3-4 months [
In order to evaluate the effect of anti-TB therapy on MLR, we analyzed the difference between before treatment and on discharge. We found that the MLR of patients on discharge decreased significantly, which suggested that the MLR may be changed with anti-TB therapy. At the same time, the differences were analyzed in different ages, genders, and TB location, respectively. The results showed there was statistically significant difference in all groups, which indicated that the factors did not influence the change of MLR. Wang et al. [
Current indicators to evaluate the efficacy of TB therapy have sputum smear with acid-fast bacilli turning negative, the sputum
In present, there are little evidence about the MLR and tuberculosis. Our research as a retrospective study has several limitations. Firstly, the sample size was small. Secondly, we only collected the data of peripheral blood at the time of discharge. The MLR after treatment should be collected to forecast the long-term prognosis. Besides, the MLR may have a value in early detection of treatment. The MLR should be collected in different times of treatment to make the study more valuable. Thirdly, the MLR is a nonspecific biomarker which is affected by the combination of inflammation, immune system diseases, and other tumors. The MLR of active TB patients should be compared with other respiratory disease patients to provide more information. Further studies should endeavor to assess more detailed information.
To sum up, our study showed that the MLR, as a simple, convenience, and low-cost marker, may be used for diagnosis and evaluates the response of therapy in active TB. However, more large-scale and prospective studies are needed to confirm the reliability of this study. Of course, the test cannot replace clinical symptoms and traditional examinations and should be used together to get more perfect results.
The datasets used or analyzed during the current study are available from the corresponding author on reasonable request.
The authors declare that there are no conflicts of interest.
XZ and WW contributed to the literature search, conception and design, statistical analysis, and the initial draft of the manuscript. LW, YL, and FY provided the original material and collected data. LZ edited drafts of the manuscript.
The authors thank all patients and control individuals that participated in this research. This work was supported by the Foundation of Children’s Hospital of Shanxi Province (no. 201716 to XZ).