Accuracy of C-reactive protein and a differentiated white cell count in diagnosing tuberculosis
Background: Tuberculosis (TB) is treatable with a high cure rate. In South Africa, 70% of pulmonary TB is microbiologically confirmed. Autopsy studies of HIV-positive people found 45.7% undiagnosed TB cases. Objectives: The primary objective investigated whether CRP and a differentiated white cell...
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| Format: | Article |
| Language: | English |
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AOSIS
2023-05-01
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| Series: | Southern African Journal of Infectious Diseases |
| Subjects: | |
| Online Access: | https://sajid.co.za/index.php/sajid/article/view/481 |
| _version_ | 1827909638213861376 |
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| author | Gideon Ruder Richard M.N. Carter Gina Joubert |
| author_facet | Gideon Ruder Richard M.N. Carter Gina Joubert |
| author_sort | Gideon Ruder |
| collection | DOAJ |
| description | Background: Tuberculosis (TB) is treatable with a high cure rate. In South Africa, 70% of pulmonary TB is microbiologically confirmed. Autopsy studies of HIV-positive people found 45.7% undiagnosed TB cases.
Objectives: The primary objective investigated whether CRP and a differentiated white cell count (WCC) and ratios thereof are useful screening tools for TB.
Method: This retrospective cross-sectional study included adult patients admitted to two tertiary hospitals in Bloemfontein with TB workups between April 2016 and September 2019. National Health Laboratory Service (NHLS) provided laboratory data. Tuberculosis Xpert® MTB/RIF, Xpert® MTB/RIF Ultra and TB culture were used as reference standard for TB diagnosis.
Results: The study population comprised 1294 patients; 15.1% had TB, 56.0% were male and 63.1% HIV-positive. Patients with TB were younger (p 0.0001; 95% CI: –8;–3 years). In the total population, WCC had the highest area under the curve (0.59). White cell count (p 0.0001), neutrophils (p = 0.0003) and lymphocytes (p = 0.0394) were lower in TB patients, and CRP-WCC ratio (CWR) (p = 0.0009) and CRP-lymphocyte ratio (CLR) (p = 0.0386) higher. In HIV-positive patients, WCC (p = 0.0003), neutrophils (p = 0.002) and lymphocytes (p = 0.0491) were lower in TB patients and CWR (p = 0.0043) higher. No parameter reached the World Health Organization screening targets of 70% specificity with 90% sensitivity.
Conclusion: Differentiated WCC and CRP are not useful in screening hospitalised patients for TB in our setting.
Contribution: Our study guides future research to augment current screening and diagnostic algorithms for TB, specifically in advanced HIV disease. |
| first_indexed | 2024-03-13T01:40:30Z |
| format | Article |
| id | doaj.art-31eaf13c99d840d685377269d3a13c69 |
| institution | Directory Open Access Journal |
| issn | 2312-0053 2313-1810 |
| language | English |
| last_indexed | 2024-03-13T01:40:30Z |
| publishDate | 2023-05-01 |
| publisher | AOSIS |
| record_format | Article |
| series | Southern African Journal of Infectious Diseases |
| spelling | doaj.art-31eaf13c99d840d685377269d3a13c692023-07-03T14:10:23ZengAOSISSouthern African Journal of Infectious Diseases2312-00532313-18102023-05-01381e1e910.4102/sajid.v38i1.481267Accuracy of C-reactive protein and a differentiated white cell count in diagnosing tuberculosisGideon Ruder0Richard M.N. Carter1Gina Joubert2Department of Internal Medicine, Faculty of Health Sciences, University of the Free State, BloemfonteinDepartment of Internal Medicine, Faculty of Health Sciences, University of the Free State, BloemfonteinDepartment of Biostatistics, Faculty of Health Sciences, University of the Free State, BloemfonteinBackground: Tuberculosis (TB) is treatable with a high cure rate. In South Africa, 70% of pulmonary TB is microbiologically confirmed. Autopsy studies of HIV-positive people found 45.7% undiagnosed TB cases. Objectives: The primary objective investigated whether CRP and a differentiated white cell count (WCC) and ratios thereof are useful screening tools for TB. Method: This retrospective cross-sectional study included adult patients admitted to two tertiary hospitals in Bloemfontein with TB workups between April 2016 and September 2019. National Health Laboratory Service (NHLS) provided laboratory data. Tuberculosis Xpert® MTB/RIF, Xpert® MTB/RIF Ultra and TB culture were used as reference standard for TB diagnosis. Results: The study population comprised 1294 patients; 15.1% had TB, 56.0% were male and 63.1% HIV-positive. Patients with TB were younger (p 0.0001; 95% CI: –8;–3 years). In the total population, WCC had the highest area under the curve (0.59). White cell count (p 0.0001), neutrophils (p = 0.0003) and lymphocytes (p = 0.0394) were lower in TB patients, and CRP-WCC ratio (CWR) (p = 0.0009) and CRP-lymphocyte ratio (CLR) (p = 0.0386) higher. In HIV-positive patients, WCC (p = 0.0003), neutrophils (p = 0.002) and lymphocytes (p = 0.0491) were lower in TB patients and CWR (p = 0.0043) higher. No parameter reached the World Health Organization screening targets of 70% specificity with 90% sensitivity. Conclusion: Differentiated WCC and CRP are not useful in screening hospitalised patients for TB in our setting. Contribution: Our study guides future research to augment current screening and diagnostic algorithms for TB, specifically in advanced HIV disease.https://sajid.co.za/index.php/sajid/article/view/481c-reactive proteinempiric tuberculosis treatmentneutrophil-lymphocyte ratiohiv-positive peoplesmear-negative tuberculosissouth africawhite cell count |
| spellingShingle | Gideon Ruder Richard M.N. Carter Gina Joubert Accuracy of C-reactive protein and a differentiated white cell count in diagnosing tuberculosis Southern African Journal of Infectious Diseases c-reactive protein empiric tuberculosis treatment neutrophil-lymphocyte ratio hiv-positive people smear-negative tuberculosis south africa white cell count |
| title | Accuracy of C-reactive protein and a differentiated white cell count in diagnosing tuberculosis |
| title_full | Accuracy of C-reactive protein and a differentiated white cell count in diagnosing tuberculosis |
| title_fullStr | Accuracy of C-reactive protein and a differentiated white cell count in diagnosing tuberculosis |
| title_full_unstemmed | Accuracy of C-reactive protein and a differentiated white cell count in diagnosing tuberculosis |
| title_short | Accuracy of C-reactive protein and a differentiated white cell count in diagnosing tuberculosis |
| title_sort | accuracy of c reactive protein and a differentiated white cell count in diagnosing tuberculosis |
| topic | c-reactive protein empiric tuberculosis treatment neutrophil-lymphocyte ratio hiv-positive people smear-negative tuberculosis south africa white cell count |
| url | https://sajid.co.za/index.php/sajid/article/view/481 |
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