1. `
COMPARATIVE ACCURACY OF CARTRIDGE BASED NUCLEIC ACID AMPLIFICATION TEST AND SPUTUM MICROSCOPY FOR DIAGNOSIS OF PULMONARY TUBERCULOSIS IN HIV POSITIVE PATIENTS.

2. TB- HIV CO-INFECTION
Prevalence of pulmonary TB in HIV positive patients in India
10-15 percent in patients without respiratory symptoms
20-30 percent in patients with respiratory symptoms (1)
HIV patient has 50 % lifetime risk of developing tuberculosis as compared to 10 percent in HIV negative person in India (1)
1. The situation of HIV/M.Tuberculosis Co-infection in India. P.Seth.The open Infectious Disease Journal .2011;5:51-59

3. Performance of Sputum Microscopy in HIV patients
Poor sensitivity (35%-50 %) of sputum microscopy in HIV patients due to lesser number of cavities. (1)
Need for alternative measures :
Rule based tests
NAAT
Culture
1. Diagnosis and treatment of TB in HIV patients. C.Padmapriyadrshini et al. IJMR.201;130:850-65

4. Detection of pulmonary tuberculosis in HIV patients
WHO : CBNAAT
RNTCP : Sputum Microscopy

5. Performance of CBNAAT in HIV patients
CBNAAT : Real-time PCR assay , cartridge based ,no processing needed, sensitive as well as specific

6. Evidence for CBNAAT in HIV patients

7. Aims and objectives
To find out comparative accuracy of CBNAAT and sputum microscopy in HIV positive patients
To find out prevalence of Rifampicin Ressistance in HIV positive patients
Meta-analysis of CBNAAT in HIV patients incorporating our data and new studies missed by cochrane review.

8. Methodology
. We assessed HIV positive adults referred to with pulmonary symptoms suggestive of tuberculosis
. two sputum samples for microscopy using ZN stain ,one sputum sample for CBNAAT and one sputum sample for BACTEC based culture in each patient

9. Methodology
. Using BACTEC culture positive as gold standard, we determined comparative sensitivity, specificity,Positive Predictive Value, Negative Predictive value, Positive Likelihood Ratio and Negative Likelihood Ratio of CBNAAT and sputum microscopy using SPSS 15.0 software .
. We also did a meta-analysis combining various studies across the world with our study to determine pooled test performance of CBNAAT using MetaDisc 1.4 software.

10. Results :Sputum microscopy
. Out of 100 screened patients ,90 included with adequate sputum volume, 33 were culture positive and 57 were culture negative

11. Results :sputum microscopy

12. Results :CBNAAT

13. Results :CBNAAT
CBNAAT picked up 14 extra cases missed by Sputum microscopy. 2/29 patients were Rifampicin ressistant

14. Comparative Accuracy :ROC curves

15. Comparative Accuracy :ROC curves

16. Meta-analysis of Evidence

17. Meta-analysis of Evidence

18. Meta-analysis of Evidence

19. Conclusion
CBNAAT performs better than sputum microscopy in diagnosis of pulmonary tuberculosis in HIV patient
CBNAAT can tell about Rifampicin Ressistance Quickly
CBNAAT has proved superior to sputum microscopy in cochrane review and meta-analysis done by us
CBNAAT is recommended as first line modality for diagnosis of tuberculosis in HIV patients and re-treatment cases.
CBNAAT is an add-on in diagnosis of pulmonary tb in HIV negative smear negative cases with suspicion of kochs chest

20. Case : Utility of negative CBNAAT
A 40 year old HIV positive male presents with cough for two weeks , sputum AFB – 1+, CBNAAT negative

21. Case : Utility of negative CBNAAT

22. Case : Utility of negative CBNAAT
Diagnosis : Atypical Mycobacterial infection.