Journal Article > ResearchFull Text
Malar J. 2017 October 28; Volume 16 (Issue 1); 449.; DOI:10.1186/s12936-017-2094-3
Oyet C, Roh ME, Kiwanuka G, Orikiriza P, Wade M, et al.
Malar J. 2017 October 28; Volume 16 (Issue 1); 449.; DOI:10.1186/s12936-017-2094-3
BACKGROUND
Early diagnosis of suspected malaria cases with a rapid diagnostic test (RDT) has been shown to be an effective malaria control tool used in many resource-constrained settings. However, poor quality control and quality assurance hinder the accurate reporting of malaria diagnoses. Recent use of a portable, battery operated RDT reader (Deki Reader™, Fio Corporation) has shown to have high agreement with visual inspection across diverse health centre settings, however evidence of its feasibility and usability during cross sectional surveys are limited. This study aimed to evaluate the performance of the Deki Reader™ in a cross-sectional survey of children from southwestern Uganda.
METHODS
A two-stage, stratified cluster sampling survey was conducted between July and October 2014 in three districts of southwestern Uganda, with varying malaria transmission intensities. A total of 566 children aged 6-59 months were included in the analysis. Blood samples were collected and tested for malaria using: the SD Bioline Malaria Ag Pf/Pan RDT and microscopy. Results were compared between visual inspection of the RDT and by the Deki Reader™. Diagnostic performance of both methods were compared to gold-standard microscopy.
RESULTS
The sensitivity and specificity of the Deki Reader™ was 94.1% (95% CI 69.2-99.6%) and 95.6% (95% CI 93.4-97.1%), respectively. The overall percent agreement between the Deki Reader™ and visual RDT inspection was 98.9% (95% CI 93.2-99.8), with kappa statistic of 0.92 (95% CI 0.85-0.98).
CONCLUSIONS
The findings from this study suggest that the Deki Reader™ is comparable to visual inspection and performs well in detecting microscopy-positive Plasmodium falciparum cases in a household survey setting. However, the reader's performance was highly dependent on ensuring adequate battery life and a work environment free of dirt particles.
Early diagnosis of suspected malaria cases with a rapid diagnostic test (RDT) has been shown to be an effective malaria control tool used in many resource-constrained settings. However, poor quality control and quality assurance hinder the accurate reporting of malaria diagnoses. Recent use of a portable, battery operated RDT reader (Deki Reader™, Fio Corporation) has shown to have high agreement with visual inspection across diverse health centre settings, however evidence of its feasibility and usability during cross sectional surveys are limited. This study aimed to evaluate the performance of the Deki Reader™ in a cross-sectional survey of children from southwestern Uganda.
METHODS
A two-stage, stratified cluster sampling survey was conducted between July and October 2014 in three districts of southwestern Uganda, with varying malaria transmission intensities. A total of 566 children aged 6-59 months were included in the analysis. Blood samples were collected and tested for malaria using: the SD Bioline Malaria Ag Pf/Pan RDT and microscopy. Results were compared between visual inspection of the RDT and by the Deki Reader™. Diagnostic performance of both methods were compared to gold-standard microscopy.
RESULTS
The sensitivity and specificity of the Deki Reader™ was 94.1% (95% CI 69.2-99.6%) and 95.6% (95% CI 93.4-97.1%), respectively. The overall percent agreement between the Deki Reader™ and visual RDT inspection was 98.9% (95% CI 93.2-99.8), with kappa statistic of 0.92 (95% CI 0.85-0.98).
CONCLUSIONS
The findings from this study suggest that the Deki Reader™ is comparable to visual inspection and performs well in detecting microscopy-positive Plasmodium falciparum cases in a household survey setting. However, the reader's performance was highly dependent on ensuring adequate battery life and a work environment free of dirt particles.
Journal Article > ResearchFull Text
East Afr Med J. 2017 March 31; Volume 6 (Issue 2); 383.; DOI:10.4102/ajlm.v6i2.383
Orikiriza P, Nyehangane D, Atwine D, Kisakye JJ, Kassaza K, et al.
East Afr Med J. 2017 March 31; Volume 6 (Issue 2); 383.; DOI:10.4102/ajlm.v6i2.383
BACKGROUND
To confirm presence of Mycobacterium tuberculosis complex, some tuberculosis culture laboratories still rely on para-nitrobenzoic acid (PNB), a traditional technique that requires sub-culturing of clinical isolates and two to three weeks to give results. Rapid identification tests have improved turnaround times for mycobacterial culture results. Considering the challenges of the PNB method, we assessed the performance of the SD Bioline TB Ag MPT64 assay by using PNB as gold standard to detect M. tuberculosis complex from acid-fast bacilli (AFB) positive cultures.
OBJECTIVES
The aim of this study was to determine the sensitivity, specificity and turnaround time of the SD MPT64 assay for identification of M. tuberculosis complex, in a setting with high prevalence of tuberculosis and HIV.
METHODS
A convenience sample of 690 patients, with tuberculosis symptoms, was enrolled at Epicentre Mbarara Research Centre between April 2010 and June 2011. The samples were decontaminated using NALC-NaOH and re-suspended sediments inoculated in Mycobacterium Growth Indicator Tubes (MGIT) media, then incubated at 37 °C for a maximum of eight weeks. A random sample of 50 known negative cultures and 50 non-tuberculous mycobacteria isolates were tested for specificity, while sensitivity was based on AFB positivity. The time required from positive culture to reporting of results was also assessed with PNB used as the gold standard.
RESULTS
Of the 138 cultures that were AFB-positive, the sensitivity of the SD MPT64 assay was 100.0% [95% CI: 97.3 - 100] and specificity was 100.0% (95% CI, 96.4 - 100). The median time from a specimen receipt to confirmation of strain was 10 days [IQR: 8-12] with SD MPT64 and 24 days [IQR: 22-26] with PNB.
CONCLUSION
The SD MPT64 assay is comparable to PNB for identification of M. tuberculosis complex and reduces the time to detection.
To confirm presence of Mycobacterium tuberculosis complex, some tuberculosis culture laboratories still rely on para-nitrobenzoic acid (PNB), a traditional technique that requires sub-culturing of clinical isolates and two to three weeks to give results. Rapid identification tests have improved turnaround times for mycobacterial culture results. Considering the challenges of the PNB method, we assessed the performance of the SD Bioline TB Ag MPT64 assay by using PNB as gold standard to detect M. tuberculosis complex from acid-fast bacilli (AFB) positive cultures.
OBJECTIVES
The aim of this study was to determine the sensitivity, specificity and turnaround time of the SD MPT64 assay for identification of M. tuberculosis complex, in a setting with high prevalence of tuberculosis and HIV.
METHODS
A convenience sample of 690 patients, with tuberculosis symptoms, was enrolled at Epicentre Mbarara Research Centre between April 2010 and June 2011. The samples were decontaminated using NALC-NaOH and re-suspended sediments inoculated in Mycobacterium Growth Indicator Tubes (MGIT) media, then incubated at 37 °C for a maximum of eight weeks. A random sample of 50 known negative cultures and 50 non-tuberculous mycobacteria isolates were tested for specificity, while sensitivity was based on AFB positivity. The time required from positive culture to reporting of results was also assessed with PNB used as the gold standard.
RESULTS
Of the 138 cultures that were AFB-positive, the sensitivity of the SD MPT64 assay was 100.0% [95% CI: 97.3 - 100] and specificity was 100.0% (95% CI, 96.4 - 100). The median time from a specimen receipt to confirmation of strain was 10 days [IQR: 8-12] with SD MPT64 and 24 days [IQR: 22-26] with PNB.
CONCLUSION
The SD MPT64 assay is comparable to PNB for identification of M. tuberculosis complex and reduces the time to detection.
Journal Article > ResearchFull Text
PLOS One. 2015 February 6; Volume 10 (Issue 2); DOI:10.1371/journal.pone.0118191
Orikiriza P, Tibenderana B, Siedner MJ, Mueller YK, Byarugaba F, et al.
PLOS One. 2015 February 6; Volume 10 (Issue 2); DOI:10.1371/journal.pone.0118191
There are limited data on region-specific drug susceptibility of tuberculosis (TB) in Uganda. We performed resistance testing on specimens collected from treatment-naive patients with pulmonary TB in Southwestern Uganda for first and second line anti-TB drugs. We sought to provide data to guide regional recommendations for empiric TB therapy.
Journal Article > ResearchSubscription Only
Pediatrics. 2023 March 23; Online ahead of print; DOI:10.1542/peds.2022-057912
Bonnet MMB, Nordholm AC, Ssekyanzi B, Byamukama O, Orikiriza P, et al.
Pediatrics. 2023 March 23; Online ahead of print; DOI:10.1542/peds.2022-057912
BACKGROUND AND OBJECTIVES:
Children experience high tuberculosis (TB)-related mortality but causes of death among those with presumptive TB are poorly documented. We describe the mortality, likely causes of death, and associated risk factors among vulnerable children admitted with presumptive TB in rural Uganda.
METHODS:
We conducted a prospective study of vulnerable children, defined as <2 years of age, HIV-positive, or severely malnourished, with a clinical suspicion of TB. Children were assessed for TB and followed for 24 weeks. TB classification and likely cause of death were assessed by an expert endpoint review committee, including insight gained from minimally invasive autopsies, when possible.
RESULTS:
Of the 219 children included, 157 (71.7%) were <2 years of age, 72 (32.9%) were HIV-positive, and 184 (84.0%) were severely malnourished. Seventy-one (32.4%) were classified as “likely tuberculosis” (15 confirmed and 56 unconfirmed), and 72 (32.9%) died. The median time to death was 12 days. The most frequent causes of death, ascertained for 59 children (81.9%), including 23 cases with autopsy results, were severe pneumonia excluding confirmed TB (23.7%), hypovolemic shock due to diarrhea (20.3%), cardiac failure (13.6%), severe sepsis (13.6%), and confirmed TB (10.2%). Mortality risk factors were confirmed TB (adjusted hazard ratio [aHR] = 2.84 [95% confidence interval (CI): 1.19–6.77]), being HIV-positive (aHR = 2.45 [95% CI: 1.37–4.38]), and severe clinical state on admission (aHR = 2.45 [95% CI: 1.29–4.66]).
CONCLUSIONS:
Vulnerable children hospitalized with presumptive TB experienced high mortality. A better understanding of the likely causes of death in this group is important to guide empirical management.
Children experience high tuberculosis (TB)-related mortality but causes of death among those with presumptive TB are poorly documented. We describe the mortality, likely causes of death, and associated risk factors among vulnerable children admitted with presumptive TB in rural Uganda.
METHODS:
We conducted a prospective study of vulnerable children, defined as <2 years of age, HIV-positive, or severely malnourished, with a clinical suspicion of TB. Children were assessed for TB and followed for 24 weeks. TB classification and likely cause of death were assessed by an expert endpoint review committee, including insight gained from minimally invasive autopsies, when possible.
RESULTS:
Of the 219 children included, 157 (71.7%) were <2 years of age, 72 (32.9%) were HIV-positive, and 184 (84.0%) were severely malnourished. Seventy-one (32.4%) were classified as “likely tuberculosis” (15 confirmed and 56 unconfirmed), and 72 (32.9%) died. The median time to death was 12 days. The most frequent causes of death, ascertained for 59 children (81.9%), including 23 cases with autopsy results, were severe pneumonia excluding confirmed TB (23.7%), hypovolemic shock due to diarrhea (20.3%), cardiac failure (13.6%), severe sepsis (13.6%), and confirmed TB (10.2%). Mortality risk factors were confirmed TB (adjusted hazard ratio [aHR] = 2.84 [95% confidence interval (CI): 1.19–6.77]), being HIV-positive (aHR = 2.45 [95% CI: 1.37–4.38]), and severe clinical state on admission (aHR = 2.45 [95% CI: 1.29–4.66]).
CONCLUSIONS:
Vulnerable children hospitalized with presumptive TB experienced high mortality. A better understanding of the likely causes of death in this group is important to guide empirical management.
Journal Article > ResearchAbstract
Pediatr Infect Dis J. 2017 August 2; Volume 37 (Issue 2); 147-152.; DOI:10.1097/INF.0000000000001727
Bonnet MMB, Nansumba M, Bastard M, Orikiriza P, Kyomugasho N, et al.
Pediatr Infect Dis J. 2017 August 2; Volume 37 (Issue 2); 147-152.; DOI:10.1097/INF.0000000000001727
BACKGROUND
Mortality among children with presumptive tuberculosis (TB) empiric TB treatment can be high. We describe the predictors of death among children with presumptive TB, and the relation between treatment and mortality.
METHODS
A prospective cohort of children with presumptive TB who underwent clinical assessment, chest radiograph, tuberculin skin test and sputum bacterial tests for TB was followed up for 3 months. TB diagnosis was based on mycobacterial, clinical and radiologic findings. Predictors of deaths were determined using cox regression model.
RESULTS
Of 360 children included in the analysis, 31.4% were younger than 2 years; 31.6% were HIV infected and 11.3% were severely malnourished. One hundred forty (38.9%) were diagnosed with TB, 18 (13%) of whom were bacteriologically confirmed. At 3 months of follow up, 25 of 360 (6.9%) children had died: 15 of 140 (10.7%) were receiving TB treatment versus 10 of 220 (4.5%) were not receiving treatment (P = 0.025). Severely malnourished children [adjusted hazard ratio (aHR), 9.86; 95% confidence interval (CI): 3.11-31.23] and those with chest radiographs suggestive of TB (aHR, 4.20; 95% CI: 0.93-19.01) were more likely to die. Children receiving empiric TB treatment had an increased risk of death (aHR, 2.37; 95% CI: 1.01-5.55) compared with children without treatment after adjustment for age, sex, HIV status and Bacillus Calmette-Guérin (BCG) vaccination.
CONCLUSIONS
The high mortality in children receiving empirically TB treatment highlights the difficulty in diagnosing childhood TB, the increased likelihood of starting treatment in critically ill children and in children with chronic disease, and the possibility of misdiagnosis. It strengthens the need to invest further in early TB detection and diagnosing nonsevere illness.
Mortality among children with presumptive tuberculosis (TB) empiric TB treatment can be high. We describe the predictors of death among children with presumptive TB, and the relation between treatment and mortality.
METHODS
A prospective cohort of children with presumptive TB who underwent clinical assessment, chest radiograph, tuberculin skin test and sputum bacterial tests for TB was followed up for 3 months. TB diagnosis was based on mycobacterial, clinical and radiologic findings. Predictors of deaths were determined using cox regression model.
RESULTS
Of 360 children included in the analysis, 31.4% were younger than 2 years; 31.6% were HIV infected and 11.3% were severely malnourished. One hundred forty (38.9%) were diagnosed with TB, 18 (13%) of whom were bacteriologically confirmed. At 3 months of follow up, 25 of 360 (6.9%) children had died: 15 of 140 (10.7%) were receiving TB treatment versus 10 of 220 (4.5%) were not receiving treatment (P = 0.025). Severely malnourished children [adjusted hazard ratio (aHR), 9.86; 95% confidence interval (CI): 3.11-31.23] and those with chest radiographs suggestive of TB (aHR, 4.20; 95% CI: 0.93-19.01) were more likely to die. Children receiving empiric TB treatment had an increased risk of death (aHR, 2.37; 95% CI: 1.01-5.55) compared with children without treatment after adjustment for age, sex, HIV status and Bacillus Calmette-Guérin (BCG) vaccination.
CONCLUSIONS
The high mortality in children receiving empirically TB treatment highlights the difficulty in diagnosing childhood TB, the increased likelihood of starting treatment in critically ill children and in children with chronic disease, and the possibility of misdiagnosis. It strengthens the need to invest further in early TB detection and diagnosing nonsevere illness.
Journal Article > ResearchAbstract
J Clin Microbiol. 2019 October 16
Ardizzoni E, Orikiriza P, Ssuuna C, Nyehangane D, Gumsboga M, et al.
J Clin Microbiol. 2019 October 16
Background: Xpert MTB/RIF (Xpert) and culture are the most reliable methods for tuberculosis diagnosis but are still poorly accessible in many low resource countries. We aimed to assess the effect of OMNIgene® SPUTUM (OM-S) and ethanol in preserving sputum for Xpert and OM-S for mycobacteria growth indicator tube (MGIT) testing over a period of 15 and 8 days respectively.
Methods: Sputum were collected from newly diagnosed smear-positive patients. For Xpert, pooled samples were split into 5 aliquots: 3 for Xpert on day 0, 7 and 15 days without additive and 2 with either OM-S or ethanol at day 15. For MGIT, 2 aliquots were tested without preservative and 2 with OM-S at 0 and 8 days.
Results: A total of 48 and 47 samples were included in the analysis for Xpert and culture. With Xpert, using Day 0 as reference, untreated samples stored for 7 and 15 days showed concordance of 45/46 (97.8%) and 46/48 (95.8%). For samples preserved with OM-S or ethanol for 15 days compared with untreated samples processed at day 0 or after 15 days, OM-S concordance was 46/48(95.8%) and 47/48(97.9%), while ethanol was 44/48 (91.7%) and 45/48 (93.8%). With MGIT, concordance between untreated and OM-S treated samples was 21/41(51.2%) at Day 0 and 21/44(47.7%) at day8.
Conclusions: Xpert equally detected TB in OM-S treated and untreated samples up to 15 days but showed slightly lower detection in ethanol treated samples. Among OM-S treated samples, MGIT positivity was significantly lower compared to untreated samples at both time-points.
Methods: Sputum were collected from newly diagnosed smear-positive patients. For Xpert, pooled samples were split into 5 aliquots: 3 for Xpert on day 0, 7 and 15 days without additive and 2 with either OM-S or ethanol at day 15. For MGIT, 2 aliquots were tested without preservative and 2 with OM-S at 0 and 8 days.
Results: A total of 48 and 47 samples were included in the analysis for Xpert and culture. With Xpert, using Day 0 as reference, untreated samples stored for 7 and 15 days showed concordance of 45/46 (97.8%) and 46/48 (95.8%). For samples preserved with OM-S or ethanol for 15 days compared with untreated samples processed at day 0 or after 15 days, OM-S concordance was 46/48(95.8%) and 47/48(97.9%), while ethanol was 44/48 (91.7%) and 45/48 (93.8%). With MGIT, concordance between untreated and OM-S treated samples was 21/41(51.2%) at Day 0 and 21/44(47.7%) at day8.
Conclusions: Xpert equally detected TB in OM-S treated and untreated samples up to 15 days but showed slightly lower detection in ethanol treated samples. Among OM-S treated samples, MGIT positivity was significantly lower compared to untreated samples at both time-points.
Journal Article > ResearchFull Text
J Clin Microbiol. 2016 March 30; Volume 54 (Issue 6); 1520-1527.; DOI:10.1128/JCM.00017-16
Boum Y II, Kim S, Orikiriza P, Acuña-Villaorduña C, Vinhas S, et al.
J Clin Microbiol. 2016 March 30; Volume 54 (Issue 6); 1520-1527.; DOI:10.1128/JCM.00017-16
Sputum acid-fast bacilli (AFB) smear microscopy has suboptimal sensitivity but remains the most commonly used laboratory test to diagnose pulmonary tuberculosis (TB). We prospectively evaluated the small membrane filtration (SMF) method that concentrates AFB in a smaller area to facilitate detection to improve the diagnostic performance of microscopy. We enrolled adults with suspicion of pulmonary TB from health facilities in southwestern Uganda. Clinical history, physical examination, and 3 sputum samples were obtained for direct fluorescent AFB smear, SMF, Xpert MTB/RIF, and MGIT culture media. Sensitivity and specificity were estimated for SMF, AFB smear, and Xpert MTB/RIF, using MGIT as the reference standard. The analysis was stratified according to HIV status. From September 2012 to April 2014, 737 participants were included in the HIV-infected stratum (146 [20.5%] were culture positive) and 313 were in the HIV-uninfected stratum (85 [28%] were culture positive). In HIV-infected patients, the sensitivity of a single SMF was 67.4% (95% confidence interval [CI], 59.9% to 74.1%); for AFB, 68.0% (95% CI, 60.6% to 74.6%); and for Xpert MTB/RIF, 91.0% (95% CI, 85.0% to 94.8%). In HIV-uninfected patients, the corresponding sensitivities were 72.5% (95% CI, 62.1% to 80.9%), 80.3% (95% CI, 70.8% to 87.2%), and 93.5% (95% CI, 85.7% to 97.2%). The specificity for all 3 tests in both HIV groups was ≥96%. In this setting, the SMF method did not improve the diagnostic accuracy of sputum AFB. The Xpert MTB/RIF assay performed well in both HIV-infected and -uninfected groups.
Journal Article > ResearchFull Text
BMC Pregnancy Childbirth. 2020 July 2; Volume 20 (Issue 1); DOI:10.1186/s12884-020-03047-y
Oloya S, Lyczkowski D, Orikiriza P, Irama M, Boum Y II, et al.
BMC Pregnancy Childbirth. 2020 July 2; Volume 20 (Issue 1); DOI:10.1186/s12884-020-03047-y
Background
While congenital syphilis is a significant public health problem that can cause severe disabilities, little is known about the situation in Uganda. We describe prevalence, associated factors and clinical presentation of congenital syphilis in Mbarara, Uganda.
Methods
A cross sectional study was carried out among mother- newborn dyads from the postnatal ward of Mbarara Regional Referral Hospital (MRRH). After obtaining informed consent, a structured questionnaire was used to capture data on risk factors for congenital syphilis. A finger prick was performed on the mothers for Treponema Pallidum Haemagglutination Assay (TPHA). If TPHA was positive, a venous blood sample was collected from the mother to confirm active infection using Rapid Plasma Reagin (RPR). Venous blood was drawn from a newborn if the mother tested positive by TPHA and RPR. A newborn with RPR titres 4 times higher than the mother was considered to have congenital syphilis. We fit logistic regression models to determine factors associated with congenital syphilis.
Results
Between June and September 2015, we enrolled 2500 mothers and 2502 newborns. Prevalence of syphilis was 3.8% (95% CI 3.1–4.6) among newborn infants and 4.1% (95% CI 3.4–5.0) among their mothers. Maternal age <25 years, past history of genital ulcer, a past history of abnormal vaginal discharge, and not receiving treatment of at least one of genital ulcer, genital itching, lower abdominal pain and abnormal vaginal discharge in the current pregnancy were the risk factors associated with congenital syphilis. The most common clinical feature was hepatosplenomegaly.
Conclusions
We found higher-than-expected syphilis sero-prevalence rates in a high risk population of postnatal mothers and their newborns in Uganda. Bridge populations for syphilis may include mothers not tested during pregnancy, who are usually married and not treated. In accordance with our results, the national policy for syphilis control in Uganda should be strengthened to include universal syphilis screening amongst mother-newborn pairs in postnatal clinics with subsequent partner notification.
While congenital syphilis is a significant public health problem that can cause severe disabilities, little is known about the situation in Uganda. We describe prevalence, associated factors and clinical presentation of congenital syphilis in Mbarara, Uganda.
Methods
A cross sectional study was carried out among mother- newborn dyads from the postnatal ward of Mbarara Regional Referral Hospital (MRRH). After obtaining informed consent, a structured questionnaire was used to capture data on risk factors for congenital syphilis. A finger prick was performed on the mothers for Treponema Pallidum Haemagglutination Assay (TPHA). If TPHA was positive, a venous blood sample was collected from the mother to confirm active infection using Rapid Plasma Reagin (RPR). Venous blood was drawn from a newborn if the mother tested positive by TPHA and RPR. A newborn with RPR titres 4 times higher than the mother was considered to have congenital syphilis. We fit logistic regression models to determine factors associated with congenital syphilis.
Results
Between June and September 2015, we enrolled 2500 mothers and 2502 newborns. Prevalence of syphilis was 3.8% (95% CI 3.1–4.6) among newborn infants and 4.1% (95% CI 3.4–5.0) among their mothers. Maternal age <25 years, past history of genital ulcer, a past history of abnormal vaginal discharge, and not receiving treatment of at least one of genital ulcer, genital itching, lower abdominal pain and abnormal vaginal discharge in the current pregnancy were the risk factors associated with congenital syphilis. The most common clinical feature was hepatosplenomegaly.
Conclusions
We found higher-than-expected syphilis sero-prevalence rates in a high risk population of postnatal mothers and their newborns in Uganda. Bridge populations for syphilis may include mothers not tested during pregnancy, who are usually married and not treated. In accordance with our results, the national policy for syphilis control in Uganda should be strengthened to include universal syphilis screening amongst mother-newborn pairs in postnatal clinics with subsequent partner notification.
Journal Article > ResearchFull Text
Clin Microbiol Infect. 2018 May 8; Volume 37 (Issue 8); 1465-1473.; DOI:10.1007/s10096-018-3272-0
Orikiriza P, Nansumba M, Nyehangane D, Bastard M, Mugisha IT, et al.
Clin Microbiol Infect. 2018 May 8; Volume 37 (Issue 8); 1465-1473.; DOI:10.1007/s10096-018-3272-0
The Xpert MTB/RIF assay is a major advance for diagnosis of tuberculosis (TB) in high-burden countries but is limited in children by their difficulty to produce sputum. We investigated TB in sputum and stool from children with the aim of improving paediatric TB diagnosis. A prospective cohort of children with presumptive TB, provided two sputum or induced sputum at enrolment in a regional referral hospital in Uganda. Stool was collected from those started on TB treatment. All specimen were tested for Xpert MTB/RIF, mycobacteria growth indicator tube (MGIT), Lowenstein Jensen cultures and microscopy (except stool). We compared TB detection between age categories and assessed the performance of Xpert MTB/RIF in sputum and stool. Of the 392 children enrolled, 357 (91.1%) produced at least one sputum sample. Sputum culture yield was 13/357 (3.6%): 3/109 (2.6%), 3/89 (3.2%), 3/101 (2.6%) and 4/44 (8.2%) among children of < 2, 2-5, ≥ 5-10 and > 10 years, respectively (p = 0.599). Xpert MTB/RIF yield was 14/350 (4.0%): 3/104 (2.9%), 4/92 (4.3%), 3/88 (2.9%) and 4/50 (.0%), respectively (p = 0.283). Sensitivity and specificity of Xpert MTB/RIF in sputum against sputum culture were 90.9% (95% CI 58.7-99.8) and 99.1% (99.1-99.8). In stool, it was 55.6% (21.2-86.3) and 98.2% (98.2-100) against Xpert MTB/RIF and culture in sputum. Only a minority of children had microbiologically confirmed TB with a higher proportion in children above 10 years. Although sensitivity of Xpert MTB/RIF in stool was low, with good optimization, it might be a good alternative to sputum in children.
Journal Article > ResearchAbstract Only
Eur Respir J. 2021 June 17; Volume 59 (Issue 1); 2101116.; DOI:10.1183/13993003.01116-2021
Orikiriza P, Smith JS, Ssekyanzi B, Nyehangane D, Mugisha IT, et al.
Eur Respir J. 2021 June 17; Volume 59 (Issue 1); 2101116.; DOI:10.1183/13993003.01116-2021
BACKGROUND
Non-sputum-based diagnostic approaches are crucial in children at high risk of disseminated tuberculosis (TB) who cannot expectorate sputum. We evaluated the diagnostic accuracy of stool Xpert MTB/RIF and urine AlereLAM tests in this group of children.
METHODS
Hospitalised children with presumptive TB and either age <2 years, HIV-positive or with severe malnutrition were enrolled in a diagnostic cohort. At enrolment, we attempted to collect two urine, two stool and two respiratory samples. Urine and stool were tested with AlereLAM and Xpert MTB/RIF, respectively. Respiratory samples were tested with Xpert MTB/RIF and mycobacterial culture. Both a microbiological and a composite clinical reference standard were used.
RESULTS
The study analysed 219 children; median age 16.4 months, 72 (32.9%) HIV-positive and 184 (84.4%) severely malnourished. 12 (5.5%) and 58 (28.5%) children had confirmed and unconfirmed TB, respectively. Stool and urine were collected in 219 (100%) and 216 (98.6%) children, respectively. Against the microbiological reference standard, the sensitivity and specificity of stool Xpert MTB/RIF was 50.0% (6/12, 95% CI 21.1–78.9%) and 99.1% (198/200, 95% 96.4–99.9%), while that of urine AlereLAM was 50.0% (6/12, 95% 21.1–78.9%) and 74.6% (147/197, 95% 67.9–80.5%), respectively. Against the composite reference standard, sensitivity was reduced to 11.4% (8/70) for stool and 26.2% (17/68) for urine, with no major difference by age group (<2 and ≥2 years) or HIV status.
CONCLUSIONS
The Xpert MTB/RIF assay has excellent specificity on stool, but sensitivity is suboptimal. Urine AlereLAM is compromised by poor sensitivity and specificity in children.
Non-sputum-based diagnostic approaches are crucial in children at high risk of disseminated tuberculosis (TB) who cannot expectorate sputum. We evaluated the diagnostic accuracy of stool Xpert MTB/RIF and urine AlereLAM tests in this group of children.
METHODS
Hospitalised children with presumptive TB and either age <2 years, HIV-positive or with severe malnutrition were enrolled in a diagnostic cohort. At enrolment, we attempted to collect two urine, two stool and two respiratory samples. Urine and stool were tested with AlereLAM and Xpert MTB/RIF, respectively. Respiratory samples were tested with Xpert MTB/RIF and mycobacterial culture. Both a microbiological and a composite clinical reference standard were used.
RESULTS
The study analysed 219 children; median age 16.4 months, 72 (32.9%) HIV-positive and 184 (84.4%) severely malnourished. 12 (5.5%) and 58 (28.5%) children had confirmed and unconfirmed TB, respectively. Stool and urine were collected in 219 (100%) and 216 (98.6%) children, respectively. Against the microbiological reference standard, the sensitivity and specificity of stool Xpert MTB/RIF was 50.0% (6/12, 95% CI 21.1–78.9%) and 99.1% (198/200, 95% 96.4–99.9%), while that of urine AlereLAM was 50.0% (6/12, 95% 21.1–78.9%) and 74.6% (147/197, 95% 67.9–80.5%), respectively. Against the composite reference standard, sensitivity was reduced to 11.4% (8/70) for stool and 26.2% (17/68) for urine, with no major difference by age group (<2 and ≥2 years) or HIV status.
CONCLUSIONS
The Xpert MTB/RIF assay has excellent specificity on stool, but sensitivity is suboptimal. Urine AlereLAM is compromised by poor sensitivity and specificity in children.