Evaluation of GeneXpert MTB/RIF as a diagnostic tool in patients with sputum smear-negative TB in a high HIV burden region in Nigeria

2020 ◽  
Vol 114 (9) ◽  
pp. 697-699
Author(s):  
Abdulwasiu Bolaji Tiamiyu ◽  
Garba Iliyasu ◽  
Farouq Muhammad Dayyab ◽  
Zaiyad Garba Habib ◽  
Sirajo Haliru Tambuwal ◽  
...  

Abstract Background There are challenges in the diagnosis of TB in people with smear-negative pulmonary TB (SNPTB) in resource-limited settings. We evaluated the diagnostic usefulness of Xpert MTB/RIF compared with TB culture among SNPTB. Methods The study was a cross-sectional study among patients with SNPTB. The Xpert MTB/RIF tests and sputum culture (using Lowenstein-Jensen medium) were performed. Sensitivity and specificity were calculated. Results Of 150 patients studied, the sensitivity and specificity of GeneXpert MTB/RIF were 81.8 and 97.4%, respectively. Conclusion The sensitivity and specificity of Xpert MTB/RIF assay was comparative with culture in SNPTB patients.

Author(s):  
Tade Bagbi ◽  
Ningthoukhongjam Reema ◽  
S. Bhagyabati Devi ◽  
Thangjam Gautam Singh ◽  
Mohammad Jaleel ◽  
...  

Abstract Introduction Tuberculosis (TB) in people living with human immunodeficiency virus (PLHIV) is difficult to diagnose due to fewer organisms in sputum and extrapulmonary samples. Sputum culture takes 4 to 8 weeks for growth of the mycobacteria. Delayed treatment for TB in PLHIV leads to increased mortality. This study evaluated cartridge-based nucleic acid amplification test (CBNAAT) as a diagnostic tool for diagnosis of pulmonary TB (PTB) and extrapulmonary TB (EPTB) in PLHIV in the second most HIV prevalent state in India and for comparing its efficacy between Ziehl–Neelsen (ZN) staining sputum smear–positive and sputum smear–negative TB. Methods This cross-sectional study was conducted in RIMS, Imphal, with 167 PLHIV patients, age 15 years or older, having signs and symptoms of TB. Appropriate samples for sputum microscopy and CBNAAT were sent. Conclusion The overall sensitivity of sputum smear for acid-fast bacillus (AFB) was found to be 30.71% and that of CBNAAT was 38.57%. Sensitivity of CBNAAT for sputum smear–positive and sputum smear–negative TB was 100 and 11.3%, respectively. Sensitivity of ZN smear for AFB of EPTB sample was 48.1% and that of CBNAAT was 59.25%. In both PTB and EPTB, CBNAAT showed an increase in diagnosis of microbiologically confirmed PTB cases by 7.8 and 11.1%, respectively, over and above the cases diagnosed by ZN smear microscopy. Rifampicin resistance was detected in five patients. We conclude that CBNAAT is a rapid test with better sensitivity in diagnosis of PTB and EPTB in PLHIV, compared with ZN smear microscopy. It detects rifampicin resistance for multidrug-resistant TB and helps in early treatment intervention.


BMJ Open ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. e020590 ◽  
Author(s):  
Henok Getachew Tegegn ◽  
Yonas Getaye Tefera ◽  
Daniel Asfaw Erku ◽  
Kaleab Taye Haile ◽  
Tamrat Befekadu Abebe ◽  
...  

2021 ◽  
Vol 49 (1) ◽  
Author(s):  
Teresia Maina ◽  
Annie Willetts ◽  
Moses Ngari ◽  
Abdullahi Osman

Abstract Background Tuberculosis (TB) remains a top global health problem and its transmission rate among contacts is higher when they are cohabiting with a person who is sputum smear-positive. Our study aimed to describe the prevalence of TB among student contacts in the university and determine factors associated with TB transmission. Methods We performed a cross-sectional study with an active contact case finding approach among students receiving treatment at Kilifi County Hospital from January 2016 to December 2017. The study was conducted in a public university in Kilifi County, a rural area within the resource-limited context of Kenya. The study population included students attending the university and identified as sharing accommodation or off-campus hostels, or a close social contact to an index case. The index case was defined as a fellow university student diagnosed with TB at the Kilifi County Hospital during the study period. Contacts were traced and tested for TB using GeneXpert. Results Among the 57 eligible index students identified, 51 (89%) agreed to participate. A total of 156 student contacts were recruited, screened and provided a sputum sample. The prevalence of TB (GeneXpert test positive/clinical diagnosis) among all contacts was 8.3% (95% CI 4.5–14%). Among the 8.3% testing positive 3.2% (95% CI 1.0–7.3%) were positive for GeneXpert only. Sharing a bed with an index case was the only factor significantly associated with TB infection. No other demographic or clinical factor was associated with TB infection. Conclusion Our study identified a high level of TB transmission among university students who had contact with the index cases. The study justifies further research to explore the genetic sequence and magnitude of TB transmission among students in overcrowded university in resource limited contexts.


BMJ Open ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. e037913
Author(s):  
Mala George ◽  
Geert-Jan Dinant ◽  
Efrem Kentiba ◽  
Teklu Teshome ◽  
Abinet Teshome ◽  
...  

ObjectivesTo evaluate the performance of the predictors in estimating the probability of pulmonary tuberculosis (PTB) when all versus only significant variables are combined into a decision model (1) among all clinical suspects and (2) among smear-negative cases based on the results of culture tests.DesignA cross-sectional study.SettingTwo public referral hospitals in Tigray, Ethiopia.ParticipantsA total of 426 consecutive adult patients admitted to the hospitals with clinical suspicion of PTB were screened by sputum smear microscopy and chest radiograph (chest X-ray (CXR)) in accordance with the Ethiopian guidelines of the National Tuberculosis and Leprosy Program. Discontinuation of antituberculosis therapy in the past 3 months, unproductive cough, HIV positivity and unwillingness to give written informed consent were the basis of exclusion from the study.Primary and secondary outcome measuresA total of 354 patients were included in the final analysis, while 72 patients were excluded because culture tests were not done.ResultsThe strongest predictive variables of culture-positive PTB among patients with clinical suspicion were a positive smear test (OR 172; 95% CI 23.23 to 1273.54) and having CXR lesions compatible with PTB (OR 10.401; 95% CI 5.862 to 18.454). The regression model had a good predictive performance for identifying culture-positive PTB among patients with clinical suspicion (area under the curve (AUC) 0.84), but it was rather poor in patients with a negative smear result (AUC 0.64). Combining all the predictors in the model compared with only the independent significant variables did not really improve its performance to identify culture-positive (AUC 0.84–0.87) and culture-negative (AUC 0.64–0.69) PTB.ConclusionsOur finding suggests that predictive models based on clinical variables will not be useful to discriminate patients with culture-negative PTB from patients with culture-positive PTB among patients with smear-negative cases.


Author(s):  
R. Behzadmehr ◽  
E. Nejadkehkha

Despite many advances in the diagnosis, screening, and rapid treatment of tuberculosis, it is still a public health concern in the world. Due to the importance of this issue in diagnosis and reduction of transmission of infection and treatment of the disease especially where this study is conducted due to the high prevalence of tuberculosis, this study was done to determine The relationship between sputum smear positivity grade and chest X-ray findings in pulmonary tuberculosis patients in a hospital in southeast of Iran. This cross-sectional study was performed on all patients with pulmonary TB referencing the health centers in Zabol city, southeast of Iran from 1 January 2015 to 30 December 2020. Sputum smear and radiographic findings of the chest X-ray were evaluated. Data was collected using a form of information and finally analyzed by SPSS 22. Out of 101 patients examined in the present study, 71 were women and 30 were men. The mean age of the patients was 62.68 ± 13.61 years. The frequency of opacity in patients with grades 1, 2, and 3 was 71.4, 78.5, and 76.5%, respectively. Frequency of cavitation in patients with Grade 1, 2 and 3 was 11.5%, 28.5% and 52.9% respectively (P value 0.001). The frequency of reticulonodular presentations in patients with grade 1, 2, and 3 was 24.2, 7.1, and 0%, respectively.  In general, the results of this study showed that, with increasing grading of smears (1+, 2+, and 3+), the frequency of cavitation presentation increased significantly and the frequency of reticulonodular presentations decreased significantly. In general, the results of this study showed that, with increasing grading of smears (, the frequency of Cavitation presentation increased significantly and the frequency of reticulonodular presentations decreased significantly. The findings of the present study can help physicians better diagnose TB.


Author(s):  
Nivedita Sinha ◽  
Alpana Singh ◽  
BD Banerjee ◽  
Rachna Agarwal ◽  
Himsweta Srivastva

Indroduction: Miscarriage is the most common complication of pregnancy. Defective implantation is one of the common causes of miscarriage. Pregnancy Associated Plasma Protein-A (PAPP-A) is secreted from syncytiotrophoblast and it enables trophoblast invasion. Few studies have shown association of PAPP-A with miscarriage. However, there is limited data available to establish the role of PAPP-A as a predictive marker of miscarriage, especially in Indian population. Aim: To determine the potential of maternal PAPP-A level estimation in asymptomatic women in late first trimester (10-13 weeks) with viable foetus in predicting subsequent miscarriage. Materials and Methods: This was an observational, cross-sectional study conducted from November 2016 to April 2018 at University College of Medical Science and Guru Teg Bahadur Hospital, Delhi, India. Asymptomatic pregnant women (N=500) at 10-13 weeks of gestation were recruited from an antenatal clinic after confirmation of foetal viability. A 2 mL of blood sample was collected and serum PAPP-A level was measured. Independent t-test and Chi-square test was used to compare continuous data and Mann-Whitney U test was used to compare PAPP-A Multiple of Median (MOM). Logistic regression was used to estimate risk of miscarriage. Results: Out of 500 participants, 9 were lost to follow-up. From remaining N=491, 32 (6.5%) women had a miscarriage. PAPP-A levels were significantly decreased in miscarriage group compared to ongoing pregnancy group with median MOM 0.116 (0.080-0.17) and 1.25 (0.665-3.249) respectively (p-value <0.001). PAPP-A MOM value of ≤10th percentile sensitivity and specificity of detection of miscarriage was 81.25% and 94.98% and at ≤5th percentile sensitivity and specificity was 40.62% and 97.82%, respectively. Lower the percentile cut-off of serum PAPP-A value, higher was the specificity and positive predictive value for prediction of miscarriage. By applying logistic regression we found that if PAPP-A MOM decreases by 1 unit the chances of miscarriage increased by 1.2 times. By this model 63.2% of cases could be explained (Nagelkerke R Square=0.632). For prediction of pregnancies likely to miscarry, the area under Receiver Operator Characteristic (ROC) curve (95% CI) was 0.969 (0.955-0.983). Conclusion: Low serum PAPP-A levels from asymptomatic women in late 1st trimester is a good predictive marker of miscarriage.


Author(s):  
Jovilia Abong ◽  
Victoria Dalay ◽  
Ivor Langley ◽  
Ewan Tomeny ◽  
Danaida Marcelo ◽  
...  

Setting A high proportion of notified tuberculosis cases in the Philippines are clinically diagnosed (63%) as opposed to bacteriologically confirmed. Better understanding of this phenomenon is required to improve tuberculosis control. Objectives To determine the percentage of Smear Negative Presumptive Tuberculosis patients that would be diagnosed by GeneXpert; compare clinical characteristics of patients diagnosed as tuberculosis cases; and review the impact that the current single government physician and a reconstituted Tuberculosis Diagnostic committee (Expert Panel) may have on tuberculosis over-diagnosis. Design This is a cross-sectional study of 152 patients 15-85 years old with two negative Direct Sputum Smear Microscopy results, with abnormal chest X-ray who underwent GeneXpert testing and review by an Expert Panel. Results 31% (48/152) of the sample were Xpert positive. 93% (97/104) of GeneXpert negatives were clinically diagnosed by a Single Physician. Typical symptoms and X-ray findings were higher in bacteriologically confirmed tuberculosis. When compared to GeneXpert results, the Expert panel&rsquo;s sensitivity for active tuberculosis was high (97.5%, 39/40) but specificity was low (40.2%, 35/87). Conclusion Using the GeneXpert would increase the level of bacteriologically confirmed tuberculosis substantially among presumptive Tuberculosis. An Expert panel will greatly reduce over-diagnosis usually seen when a decision is made by a Single Physician.


2020 ◽  
Author(s):  
Aude Christelle Ka'e ◽  
Samuel Martin Sosso ◽  
Joseph Fokam ◽  
Rachel Kamgaing Simo ◽  
Sara Riwom Essama ◽  
...  

Abstract Background: Toxoplasmosis remains a neglected common opportunistic infection in immunocompromised individuals, who are mainly people living with HIV (PLWHIV) in whom reactivation of toxoplasmosis may occur with advanced HIV conditions in resource-limited settings (RLS). Our objective was to evaluate the correlation between the anti-toxoplasmic IgG (Tg-IgG) concentration and the immuno-virological status of PLWHIV.Methods : A prospective and cross-sectional study was conducted among PLWHIV aged>18 years from February to November 2018 at the Chantal BIYA international Reference Centre. Blood samples were collected from eligible consenting PLWHIV; Tg-IgG level was assessed by quantitative ELISA, CD4-T lymphocytes counts were measured by flow cytometry and HIV-1 plasma viral load (PVL) measurement by real-time-PCR. Data were analysed using Excel and Graph Pad softwares; with p<0.05 considered statistically significant.Results : A total of 100 PLWHIV were enrolled: 56% seropositive for IgG anti- Toxoplasma gondii, 33% seronegative and 11% indeterminate results. According to viremia, 100% (19/19) of those with PVL>1000 copies/mL were seropositive to Tg-IgG versus 52.85% (37/70) of those with PVL<1000 copies/mL (median [IQR] IgG concentration 152.78 [139.24-444.43] versus 34.44 [13.04-36.47] IU/mL, respectively); p<0.0001. According to CD4, 100% (11/11) of those with T-CD4<200 cells/µL were seropositive to Tg-IgG versus 57.69% (45/78) of those with T-CD4>200 cells/µL (median IgG [IQR] 432.92 [145.06-450.47] versus 35.01 [15.01-38.01] IU/mL, respectively); p<0.0001. Interestingly, there were moderate-positive and strong-negative correlations respectively with HIV-1 PVL (r = 0.54; p<0.0001) and T-CD4 (r = -0.70; p<0.0001) as compared to Tg-IgG concentration. After adjusting for age, gender, immune status and PVL in logistic regression, only poor immune status (T-CD4<200 cells/µL) was independently associated to Tg-IgG seropositivity (p=0.0004).Conclusion : In a typical RLS like Cameroon, about half of PLWHIV might be seropositive to Tg-IgG. Of relevance, decreasing immunity appears with risk of increasing IgG anti- T gondii concentration, which suggests a relapse of toxoplasmosis. Thus, in the context of immunodeficiency, routine quantification of Tg-IgG would alleviate the programmatic burden of this opportunistic infection in RLS with generalized HIV epidemics.


Sign in / Sign up

Export Citation Format

Share Document