Sputum smear microscopy for tuberculosis (TB) diagnosis lacks sensitivity in HIV-infected symptomatic patients and increases the likelihood that mycobacterial infections particularly disseminated TB will be missed; delays in diagnosis can be fatal. Given the duration for MTB growth in blood culture, clinical predictors of MTB bacteremia may improve early diagnosis of mycobacteremia. We describe the predictors and mortality outcome of mycobacteremia among HIV-infected sputum smear-negative presumptive TB patients in a high prevalence HIV/TB setting.
Between January and November 2011, all consenting HIV-infected adults suspected to have TB (presumptive TB) were consecutively enrolled. Diagnostic assessment included sputum smear microscopy, urine Determine TB lipoarabinomannan (LAM) antigen test, mycobacterial sputum and blood cultures, chest X-ray, and CD4 cell counts in addition to clinical and socio-demographic data. Patients were followed for 12 months post-enrolment.
Of 394 sputum smear-negative participants [female, 63.7%; median age (IQR) 32 (28–39) years], 41/394 (10.4%) had positive mycobacterial blood cultures (mycobacteremia); all isolates were M. tuberculosis (MTB). The median CD4 cell count was significantly lower among patients with mycobacteremia when compared with those without (CD4 31 versus 122 cells/μL, p < 0.001). In a multivariate analysis, male gender [OR 3.4, 95%CI (1.4-7.6), p = 0.005], CD4 count <100 cells/μL [OR 3.1, 95% CI (1.1-8.6), p = 0.030] and a positive lateral flow urine TB LAM antigen test [OR 15.3, 95%CI (5.7-41.1), p < 0.001] were significantly associated with mycobacteremia. At 12 months of follow-up, a trend towards increased mortality was observed in patients that were MTB blood culture positive (35.3%) compared with those that were MTB blood culture negative (23.3%) (p = 0.065).
Mycobacteremia occurred in 10% of smear-negative patients and was associated with higher mortality compared with smear-negative patients without mycobacteremia. Advanced HIV disease (CD4 < 100 cells/mm3), male gender and positive lateral flow urine TB LAM test predicted mycobacteremia in HIV-infected smear-negative presumptive TB patients in this high prevalence TB/HIV setting.
Predictors; Mortality; Mycobacterial infections; Bacteremia; Smear- negative; HIV; LAM; Sub-Saharan Africa
Despite the recent innovations in tuberculosis (TB) and multi-drug resistant TB (MDR-TB) diagnosis, culture remains vital for difficult-to-diagnose patients, baseline and end-point determination for novel vaccines and drug trials. Herein, we share our experience of establishing a BSL-3 culture facility in Uganda as well as 3-years performance indicators and post-TB vaccine trials (pioneer) and funding experience of sustaining such a facility.
Between September 2008 and April 2009, the laboratory was set-up with financial support from external partners. After an initial procedure validation phase in parallel with the National TB Reference Laboratory (NTRL) and legal approvals, the laboratory registered for external quality assessment (EQA) from the NTRL, WHO, National Health Laboratories Services (NHLS), and the College of American Pathologists (CAP). The laboratory also instituted a functional quality management system (QMS). Pioneer funding ended in 2012 and the laboratory remained in self-sustainability mode.
The laboratory achieved internationally acceptable standards in both structural and biosafety requirements. Of the 14 patient samples analyzed in the procedural validation phase, agreement for all tests with NTRL was 90% (P <0.01). It started full operations in October 2009 performing smear microscopy, culture, identification, and drug susceptibility testing (DST). The annual culture workload was 7,636, 10,242, and 2,712 inoculations for the years 2010, 2011, and 2012, respectively. Other performance indicators of TB culture laboratories were also monitored. Scores from EQA panels included smear microscopy >80% in all years from NTRL, CAP, and NHLS, and culture was 100% for CAP panels and above regional average scores for all years with NHLS. Quarterly DST scores from WHO-EQA ranged from 78% to 100% in 2010, 80% to 100% in 2011, and 90 to 100% in 2012.
From our experience, it is feasible to set-up a BSL-3 TB culture laboratory with acceptable quality performance standards in resource-limited countries. With the demonstrated quality of work, the laboratory attracted more research groups and post-pioneer funding, which helped to ensure sustainability. The high skilled experts in this research laboratory also continue to provide an excellent resource for the needed national discussion of the laboratory and quality management systems.
Electronic supplementary material
The online version of this article (doi:10.1186/1478-4505-13-4) contains supplementary material, which is available to authorized users.
Acceptable quality standards; Biosafety level 3; Feasibility; Resource limited countries; TB culture
The burden of non-communicable diseases (NCDs) in low- and middle-income countries (LMICs) is accelerating. Given that the capacity of health systems in LMICs is already strained by the weight of communicable diseases, these countries find themselves facing a double burden of disease. NCDs contribute significantly to morbidity and mortality, thereby playing a major role in the cycle of poverty, and impeding development.
Integrated approaches to health service delivery and healthcare worker (HCW) training will be necessary in order to successfully combat the great challenge posed by NCDs.
In 2013, we formed the Uganda Initiative for Integrated Management of NCDs (UINCD), a multidisciplinary research collaboration that aims to present a systems approach to integrated management of chronic disease prevention, care, and the training of HCWs.
Through broad-based stakeholder engagement, catalytic partnerships, and a collective vision, UINCD is working to reframe integrated health service delivery in Uganda.
Non-communicable diseases; Health system strengthening; Integration; Multi-sectoral collaboration
In a large prospective study in Kampala, Uganda, we found that case investigation can be effective (10% yield) in early detection of active tuberculosis in children <15 years old, with 71% culture confirmation.
Background. Tuberculosis is a large source of morbidity and mortality among children. However, limited studies characterize childhood tuberculosis disease, and contact investigation is rarely implemented in high-burden settings. In one of the largest pediatric tuberculosis contact investigation studies in a resource-limited setting, we assessed the yield of contact tracing on childhood tuberculosis and indicators for disease progression in Uganda.
Methods. Child contacts aged <15 years in Kampala, Uganda, were enrolled from July 2002 to June 2009 and evaluated for tuberculosis disease via clinical, radiographic, and laboratory methods for up to 24 months.
Results. Seven hundred sixty-one child contacts were included in the analysis. Prevalence of tuberculosis in our child population was 10%, of which 71% were culture-confirmed positive. There were no cases of disseminated tuberculosis, and 483 of 490 children (99%) started on isoniazid preventative therapy did not develop disease. Multivariable testing suggested risk factors including human immunodeficiency virus (HIV) status (odds ratio [OR], 7.90; P < .001), and baseline positive tuberculin skin test (OR, 2.21; P = .03); BCG vaccination was particularly protective, especially among children aged ≤5 years (OR, 0.23; P < .001). Adult index characteristics such as sex, HIV status, and extent or severity of disease were not associated with childhood disease.
Conclusions. Contact tracing for children in high-burden settings is able to identify a large percentage of culture-confirmed positive tuberculosis cases before dissemination of disease, while suggesting factors for disease progression to identify who may benefit from targeted screening.
pediatric; child; tuberculosis; risk factors; contact tracing
Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) remains a poorly understood complication in HIV-TB patients receiving antiretroviral therapy (ART). TB-IRIS could be associated with an exaggerated immune response to TB-antigens. We compared the recovery of IFNγ responses to recall and TB-antigens and explored in vitro innate cytokine production in TB-IRIS patients.
In a prospective cohort study of HIV-TB co-infected patients treated for TB before ART initiation, we compared 18 patients who developed TB-IRIS with 18 non-IRIS controls matched for age, sex and CD4 count. We analyzed IFNγ ELISpot responses to CMV, influenza, TB and LPS before ART and during TB-IRIS. CMV and LPS stimulated ELISpot supernatants were subsequently evaluated for production of IL-12p70, IL-6, TNFα and IL-10 by Luminex.
Before ART, all responses were similar between TB-IRIS patients and non-IRIS controls. During TB-IRIS, IFNγ responses to TB and influenza antigens were comparable between TB-IRIS patients and non-IRIS controls, but responses to CMV and LPS remained significantly lower in TB-IRIS patients. Production of innate cytokines was similar between TB-IRIS patients and non-IRIS controls. However, upon LPS stimulation, IL-6/IL-10 and TNFα/IL-10 ratios were increased in TB-IRIS patients compared to non-IRIS controls.
TB-IRIS patients did not display excessive IFNγ responses to TB-antigens. In contrast, the reconstitution of CMV and LPS responses was delayed in the TB-IRIS group. For LPS, this was linked with a pro-inflammatory shift in the innate cytokine balance. These data are in support of a prominent role of the innate immune system in TB-IRIS.
HIV counselling and testing and linkage to care are crucial for successful HIV prevention and treatment. Abbreviated counselling could save time; however, its effect on HIV risk is uncertain and methods to improve linkage to care have not been studied.
We did this factorial randomised controlled study at Mulago Hospital, Uganda. Participants were randomly assigned to abbreviated or traditional HIV counselling and testing; HIV-infected patients were randomly assigned to enhanced linkage to care or standard linkage to care. All study personnel except counsellors and the data officer were masked to study group assignment. Participants had structured interviews, given once every 3 months. We compared sexual risk behaviour by counselling strategy with a 6·5% non-inferiority margin. We used Cox proportional hazards analyses to compare HIV outcomes by linkage to care over 1 year and tested for interaction by sex. This trial is registered with ClinicalTrials.gov (NCT00648232).
We enrolled 3415 participants; 1707 assigned to abbreviated counselling versus 1708 assigned to traditional. Unprotected sex with an HIV discordant or status unknown partner was similar in each group (232/823 [27·9%] vs 251/890 [28·2%], difference −0·3%, one-sided 95% CI 3·2). Loss to follow-up was lower for traditional counselling than for abbreviated counselling (adjusted hazard ratio [HR] 0·61, 95% CI 0·44–0·83). 1003 HIV-positive participants were assigned to enhanced linkage (n=504) or standard linkage to care (n=499). Linkage to care did not have a significant effect on mortality or receipt of co-trimoxazole. Time to treatment in men with CD4 cell counts of 250 cells per μL or fewer was lower for enhanced linkage versus standard linkage (adjusted HR 0·60, 95% CI 0·41–0·87) and time to HIV care was decreased among women (0·80, 0·66–0·96).
Abbreviated HIV counselling and testing did not adversely affect risk behaviour. Linkage to care interventions might decrease time to enrolment in HIV care and antiretroviral treatment and thus might affect secondary HIV transmission and improve treatment outcomes.
US National Institute of Mental Health.
Diagnosis of pleural tuberculosis (TB) using routinely available diagnostic methods is challenging due to the paucibacillary nature of the disease. Histopathology and pleural tissue TB culture involves an invasive procedure which requires expertise and appropriate equipment, both often unavailable in many health units. Xpert MTB/Rif test has been widely evaluated in sputum specimens but data on its performance in pleural TB is scarce. We evaluated the accuracy of Cepheid's Xpert MTB/Rif test on pleural fluid in the diagnosis of pleural TB in Uganda.
Consenting adult patients with exudative pleural effusions underwent pleural biopsy and the tissue obtained subjected to Lowenstein-Jensen and mycobacterial growth indicator tube MTB cultures and histopathology. Pleural fluid for Xpert MTB/Rif testing was also collected. Data on socio-demographic characteristics, clinical symptoms, HIV status and CD4 count were also collected. Sensitivity, specificity, positive and negative predictive values of Xpert MTB/Rif test on pleural fluid in pleural TB diagnosis were calculated using pleural tissue MTB culture and/or histopathology as the reference standard.
Of the 116 participants [female 50%, mean age 34 (SD ±13], 87/116 (75%) had pleural TB confirmed on pleural tissue culture and/or histopathology. The Xpert MTB/Rif test identified 25 (28.7%) of the 87 confirmed pleural TB cases. The sensitivity and specificity of Xpert MTB/Rif test were 28.7% and 96.6% respectively while the positive and negative predictive values were 96.1% and 31.1% respectively.
Xpert MTB/Rif test on pleural fluid does not accurately diagnose pleural TB and therefore cannot be used as an initial evaluation test in patients with suspected pleural TB. New, rapid and accurate tests for the diagnosis of pleural TB are still warranted.
Interferon-γ (IFN-γ) is a key cytokine in the immune response to Mycobacterium tuberculosis (Mtb). Many studies established IFN-γ responses are influenced by host genetics, however differed widely by the study design and heritability estimation method. We estimated heritability of IFN-γ responses to Mtb culture filtrate (CF), ESAT-6, and Antigen 85B (Ag85B) in 1,104 Ugandans from a household contact study. Our method separately evaluates shared environmental and genetic variance, therefore heritability estimates were not upwardly biased, ranging from 11.6% for Ag85B to 22.9% for CF. Subset analyses of individuals with latent Mtb infection or without human immunodeficiency virus infection yielded higher heritability estimates, suggesting 10–30% of variation in IFN-γ is caused by a shared environment. Immunosuppression does not negate the role of genetics on IFN-γ response. These estimates are remarkably close to those reported for components of the innate immune response. These findings have implications for the interpretation of IFN-γ response assays and vaccine studies.
Despite sustained exposure to a person with pulmonary tuberculosis (TB), some M. tuberculosis (Mtb) exposed individuals maintain a negative tuberculin skin test (TST). Our objective was to characterize these persistently negative TST (PTST-) individuals and compare them to TST converters (TSTC) and individuals who are TST positive at study enrollment.
During a TB household contact study in Kampala, Uganda, PTST-, TSTC, and TST + individuals were identified. PTST- individuals maintained a negative TST over a 2 year observation period despite prolonged exposure to an infectious tuberculosis (TB) case. Epidemiological and clinical characteristics were compared, a risk score developed by another group to capture risk for Mtb infection was computed, and an ordinal regression was performed.
When analyzed independently, epidemiological risk factors increased in prevalence from PTST- to TSTC to TST+. An ordinal regression model suggested age (p < 0.01), number of windows (p < 0.01) and people (p = 0.07) in the home, and sleeping in the same room (p < 0.01) were associated with PTST- and TSTC. As these factors do not exist in isolation, we examined a risk score, which reflects an accumulation of risk factors. This compound exposure score did not differ significantly between PTST-, TSTC, and TST+, except for the 5–15 age group (p = 0.009).
Though many individual factors differed across all three groups, an exposure risk score reflecting a collection of risk factors did not differ for PTST-, TSTC and TST + young children and adults. This is the first study to rigorously characterize the epidemiologic risk profile of individuals with persistently negative TSTs despite close exposure to a person with TB. Additional studies are needed to characterize possible epidemiologic and host factors associated with this phenotype.
Transmission risk factors; Latent Mtb infection; Exposure; Household characteristics; PPD test
Background. Systemic immune activation is a strong predictor of progression of human immunodeficiency virus type 1 (HIV-1) disease and a prominent feature of infection with Mycobacterium tuberculosis.
Objective. To understand the role of systemic immune activation and microbial translocation in HIV/tuberculosis dually infected patients over the full spectrum of HIV-1 immunodeficiency, we studied circulating sCD14 and lipopolysaccharide (LPS) and their relationship to HIV-1 activity.
Methods. Two cohorts of HIV/tuberculosis subjects defined by CD4 T-cell count at time of diagnosis of tuberculosis were studied: those with low (<350/μL) and those with high (≥350/μL) CD4 T-cell count. Circulating soluble CD14 (sCD14) and LPS were assessed.
Results. Levels of sCD14 were higher in HIV/tuberculosis with high (≥350/μL) as compared to low CD4 T-cell count (P < .001). Whereas sCD14 levels remained elevated in HIV/tuberculosis subjects with lower CD4 T-cell counts despite treatment of tuberculosis, in HIV/tuberculosis patients with higher CD4 T-cell count (≥350/μL), levels declined regardless of whether highly active antiretroviral therapy (HAART) was included with the anti-tuberculosis regimen. Circulating LPS levels in HIV/tuberculosis patients with CD4 T-cell count ≥350/μL were unaffected by treatment of tuberculosis with or without HAART.
Conclusion. During HIV/tuberculosis, systemic immune activation is dissociated from microbial translocation. Changes in circulating sCD14 and LPS are dependent on CD4 T-cell count.
HIV-1; tuberculosis; LPS; soluble CD14
Healthy household contacts (HHC) of individuals with Tuberculosis (TB) with Tuberculin Skin Test (TST) conversions are considered to harbor latent Mycobacterium tuberculosis (Mtb), and at risk for TB. The immunologic, clinical, and public health implications of TST reversions that occur following Isoniazid preventive therapy (IPT) remain controversial.
To measure frequency of TST reversion following IPT, and variation in interferon-gamma (IFN-γ) responses to Mtb, in healthy Ugandan TB HHC with primary Mtb infection evidenced by TST conversion.
Prospective cohort study of healthy, HIV-uninfected, TST-negative TB HHC with TST conversions. Repeat TST was performed 12 months following conversion (3 months following completion of 9 month IPT course) to assess for stable conversion vs. reversion. Whole blood IFN-γ responses to Mtb antigen 85B (MtbA85B) and whole Mtb bacilli (wMtb) were measured in a subset (n = 27 and n = 42, respectively) at enrollment and TST conversion, prior to initiation of IPT.
Of 122 subjects, TST reversion was noted in 25 (20.5%). There were no significant differences in demographic, clinical, or exposure variables between reverters and stable converters. At conversion, reverters had significantly smaller TST compared to stable converters (13.7 mm vs 16.4 mm, respectively; p = 0.003). At enrollment, there were no significant differences in IFN-γ responses to MtbA85B or wMTB between groups. At conversion, stable converters demonstrated significant increases in IFN-γ responses to Ag85B and wMtb compared to enrollment (p = 0.001, p<0.001, respectively), while there were no significant changes among reverters.
TST reversion following IPT is common following primary Mtb infection and associated with unique patterns of Mtb-induced IFN-γ production. We have demonstrated that immune responses to primary Mtb infection are heterogeneous, and submit that prospective longitudinal studies of cell mediated immune responses to Mtb infection be prioritized to identify immune phenotypes protective against development of TB disease.
As part of site development for clinical trials in novel TB vaccines, a cohort of infants was enrolled in eastern Uganda to estimate the incidence of tuberculosis. The study introduced several mortality reduction strategies, and evaluated the mortality among study participants at two years. The specific of objective of this sub-study was to estimate 2 year mortality and associated factors in this community-based cohort.
A community based cohort of 2500 infants was enrolled from birth up to 8 weeks of age and followed for 1–2 years. During follow up, several mortality reduction activities were implemented to enhance cohort survival and retention. The verbal autopsy process was used to assign causes of death.
A total of 152 children died over a median follow up period of 2.0 years. The overall crude mortality rate was 60.8/1000 or 32.9/1000 person years with 40 deaths per 1000 for children who died in their first year of life. Anaemia, malaria, diarrhoeal diseases and pneumonia were the top causes of death. There was no death directly attributed to tuberculosis. Significant factors associated with mortality were young age of a mother and child’s birth place not being a health facility.
The overall two year mortality in the study cohort was unacceptably high and tuberculosis disease was not identified as a cause of death. Interventions to reduce mortality of children enrolled in the cohort study did not have a significant impact. Clinical trials involving infants and young children in this setting will have to strengthen local maternal and child health services to reduce infant and child mortality.
Mortality; Infants; Factors associated with mortality; Verbal autopsy
Up to 40% of HIV-infected individuals receiving Highly Active Antiretroviral Therapy (HAART) have poor CD4+ T-cell recovery. The role of natural killer (NK) cells in immune recovery during HAART is not well understood. We described the profiles of NK cell subsets and their expression of activating receptor, NKG2D and cytotoxicity receptor NKp46 among suboptimal immune responders to despite four years of suppressive HAART.
A case control study utilized frozen peripheral blood mononuclear cells (PBMC) from a cohort of HIV-infected adults that initiated HAART in 2004/5, at CD4 < 200 cells/μl. Cases were ‘suboptimal’ responders; patients within the lowest quartile of CD4+ T-cell reconstitution, with a median CD4 count increase of 129 (-43-199) cells/μl (difference between CD4 count at baseline and after 4 years of HAART) and controls were ‘super-optimal’ responders; patients within the highest quartile of CD4 T-cell reconstitution with a median CD4 count increase of 528 (416-878) cells/μl). Expression of NK cell lineage markers (CD56+/-CD16+/-) and receptors NKG2D and NKp46, was measured among PBMC from 29 cases of ‘suboptimal’ responders’ and 23 controls of ‘super-optimal responders’, and compared among ‘suboptimal’ and ‘super-optimal’ responders. NK cell populations were compared using the Holm Sidak multiple comparison test and p values < 0.05 were considered statistically significant. Data was analyzed using FLOWJO and GraphPad Prism 6.
‘Suboptimal responders’ had a higher proportion of cytokine producing CD56++CD16+/- (CD56bri) NK cells than the ‘super-optimal responders’ p = 0.017, and CD56neg NK cells were lower among suboptimal than super-optimal responders (p = 0.007). The largest NK cell subset, CD56dim, was comparable among suboptimal responders and ‘super-optimal immune responders’. Expression of NKG2D and NKp46 receptors on NK cell subsets (CD56bri, CD56neg and CD56dim), was comparable among ‘suboptimal’ and ‘super-optimal’ immune responders.
The pro-inflammatory CD56++CD16-- NK cells were higher among ‘suboptimal’ responders relative to ‘super-optimal’ responders, despite four years of suppressive HAART. Alteration of NK cell populations could inhibit host immune responses to infections among suboptimal responders. We recommend further analysis of NK cell function among suboptimal immune responders in order to inform targeted interventions to optimize immune recovery among HAART-treated adults.
Natural killer cells; Suppressive antiretroviral therapy; HAART; Suboptimal immune recovery; HAART; Sub-saharan Africa
Good mentoring is a key variable for determining success in completing a doctoral program. We identified prevailing mentoring practices among doctoral students and their mentors, identified common challenges facing doctoral training, and proposed some solutions to enhance the quality of the doctoral training experience for both candidates and mentors at Makerere University College of Health Sciences (MakCHS).
This cross-sectional qualitative evaluation was part of the monitoring and evaluation program for doctoral training. All doctoral students and their mentors were invited for a half-day workshop through the MakCHS mailing list. Prevailing doctoral supervision and mentoring guidelines were summarised in a one-hour presentation. Participants were split into two homogenous students’ (mentees’) and mentors’ groups to discuss specific issues using a focus group discussion (FGD) guide, that highlighted four main themes in regard to the doctoral training experience; what was going well, what was not going well, proposed solutions to current challenges and perceived high priority areas for improvement. The two groups came together again and the note-takers from each group presented their data and discussions were recorded by a note-taker.
Twelve out of 36 invited mentors (33%) and 22 out of 40 invited mentees (55%) attended the workshop. Mentors and mentees noted increasing numbers of doctoral students and mentors, which provided opportunities for peer mentorship. Delays in procurement and research regulatory processes subsequently delayed students’ projects. Similarly, mentees mentioned challenges of limited; 1) infrastructure and mentors to support basic science research projects, 2) physical office space for doctoral students and their mentors, 3) skills in budgeting and finance management and 4) communication skills including conflict resolution. As solutions, the team proposed skills’ training, induction courses for doctoral students-mentor teams, and a Frequently Asked Questions’ document, to better inform mentors’, mentees’ expectations and experiences.
Systemic and infrastructural limitations affect the quality of the doctoral training experience at MaKCHS. Clinical and biomedical research infrastructure, in addition to training in research regulatory processes, procurement and finance management, communication skills and information technology, were highlighted as high priority areas for strategic interventions to improve mentoring within doctoral training of clinician scientists.
Mentorship; Doctoral training; Supervision; Capacity building; Health care; Low and middle income countries; Uganda
There are limited data on perceptions of health professionals on challenges faced by cervical cancer patients seeking healthcare in the developing countries. We explored the views of operational level health professionals on perceived barriers to cervical screening and early help–seeking for symptomatic cervical cancer and the proposed remedies to the challenges.
Fifteen key informant interviews were held with health professionals including medical directors, gynecologists, medical officers, nurses and midwives in the gynecology and obstetrics departments of two hospitals in northern Uganda during August 2012 to April 2013. We used content analysis techniques to analyze the data.
Health professionals’ perceived barriers to cervical cancer care included: (i) patients and community related barriers e.g. lack of awareness on cervical cancer and available services, discomfort with exposure of women’s genitals and perceived pain during pelvic examinations, and men’s lack of emotional support to women (ii) individual healthcare professional’s challenges e.g. inadequate knowledge and skills about cervical cancer management; (iii) health facility related barriers e.g. long distances and lack of transport to cervical cancer screening and care centers, few gynecologists and lack of pathologists, delayed histology results, lack of established palliative care services and inadequate pain control; and (iv) health policy challenges e.g. lack of specialized cancer treatment services, and lack of vaccination for human papilloma virus. Other challenges included increased number of cervical cancer patients and late stage of cervical cancer at presentations.
Operational level healthcare professionals in northern Uganda reported several practical challenges facing cervical cancer care that influence their decisions, management goals and practices. The challenges and proposed remedies can inform targeted interventions for early detection, management, and control of cervical cancer in Uganda.
Barriers to care; Cervical cancer; Northern Uganda; Healthcare professionals
Biomarkers associated with response to therapy in tuberculosis could have broad clinical utility. We postulated that the frequency of Mycobacterium tuberculosis (Mtb) specific CD8+ T cells, by virtue of detecting intracellular infection, could be a surrogate marker of response to therapy and would decrease during effective antituberculosis treatment.
Objectives: We sought to determine the relationship of Mtb specific CD4+ T cells and CD8+ T cells with duration of antituberculosis treatment.
Materials and Methods
We performed a prospective cohort study, enrolling between June 2008 and August 2010, of HIV-uninfected Ugandan adults (n = 50) with acid-fast bacillus smear-positive, culture confirmed pulmonary TB at the onset of antituberculosis treatment and the Mtb specific CD4+ and CD8+ T cell responses to ESAT-6 and CFP-10 were measured by IFN-γ ELISPOT at enrollment, week 8 and 24.
There was a significant difference in the Mtb specific CD8+ T response, but not the CD4+ T cell response, over 24 weeks of antituberculosis treatment (p<0.0001), with an early difference observed at 8 weeks of therapy (p = 0.023). At 24 weeks, the estimated Mtb specific CD8+ T cell response decreased by 58%. In contrast, there was no significant difference in the Mtb specific CD4+ T cell during the treatment. The Mtb specific CD4+ T cell response, but not the CD8+ response, was negatively impacted by the body mass index.
Our data provide evidence that the Mtb specific CD8+ T cell response declines with antituberculosis treatment and could be a surrogate marker of response to therapy. Additional research is needed to determine if the Mtb specific CD8+ T cell response can detect early treatment failure, relapse, or to predict disease progression.
Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) remains a poorly understood complication in HIV-TB co-infected patients initiating antiretroviral therapy (ART). The role of the innate immune system in TB-IRIS is becoming increasingly apparent, however the potential involvement in TB-IRIS of a leaky gut and proteins that interfere with TLR stimulation by binding PAMPs has not been investigated before. Here we aimed to investigate the innate nature of the cytokine response in TB-IRIS and to identify novel potential biomarkers.
From a large prospective cohort of HIV-TB co-infected patients receiving TB treatment, we compared 40 patients who developed TB-IRIS during the first month of ART with 40 patients matched for age, sex and baseline CD4 count who did not. We analyzed plasma levels of lipopolysaccharide (LPS)-binding protein (LBP), LPS, sCD14, endotoxin-core antibody, intestinal fatty acid-binding protein (I-FABP) and 18 pro-and anti-inflammatory cytokines before and during ART.
We observed lower baseline levels of IL-6 (p = 0.041), GCSF (p = 0.036) and LBP (p = 0.016) in TB-IRIS patients. At IRIS event, we detected higher levels of LBP, IL-1RA, IL-4, IL-6, IL-7, IL-8, G-CSF (p ≤ 0.032) and lower I-FABP levels (p = 0.013) compared to HIV-TB co-infected controls. Only IL-6 showed an independent effect in multivariate models containing significant cytokines from pre-ART (p = 0.039) and during TB-IRIS (p = 0.034).
We report pre-ART IL-6 and LBP levels as well as IL-6, LBP and I-FABP levels during IRIS-event as potential biomarkers in TB-IRIS. Our results show no evidence of the possible contribution of a leaky gut to TB-IRIS and indicate that IL-6 holds a distinct role in the disturbed innate cytokine profile before and during TB-IRIS. Future clinical studies should investigate the importance and clinical relevance of these markers for the diagnosis and treatment of TB-IRIS.
Clinical and immunological data about HIV in older adults from low and middle income countries is scarce. We aimed to describe differences between younger and older adults with HIV starting antiretroviral therapy in two low–income African countries.
Setting: HIV clinics in Uganda and Zimbabwe.
Design: Secondary exploratory cross-sectional analysis of the DART randomized controlled trial.
Outcome Measures: Clinical and laboratory characteristics were compared between adults aged 18-49 years (younger) and ≥ 50 years (older), using two exploratory multivariable logistic regression models, one with HIV viral load (measured in a subset pre-ART) and one without.
A total of 3316 eligible participants enrolled in DART were available for analysis; 219 (7%) were ≥ 50 years and 1160 (35%) were male. Across the two adjusted regression models, older adults had significantly higher systolic blood pressure, lower creatinine clearance and were consistently less likely to be females compared to younger adults with HIV. Paradoxically, the models separately suggested that older adults had statistically significant (but not clinically important) higher CD4+ cell counts and higher plasma HIV–1 viral copies at initiation. Crude associations between older age and higher baseline hemoglobin, body mass index, diastolic blood pressure and lower WHO clinical stage were not sustained in the adjusted analysis.
Our study found clinical and immunological differences between younger and older adults, in a cohort of Africans starting antiretroviral therapy. Further investigations should explore how these differences could be used to ensure equity in service delivery and affect outcomes of antiretroviral therapy.
Tuberculosis (TB) remains a global health threat with 9 million new cases and 1.4 million deaths per year. In order to develop a protective vaccine, we need to define the antigens expressed by Mycobacterium tuberculosis (Mtb), which are relevant to protective immunity in high-endemic areas.
We analysed responses to 23 Mtb antigens in a total of 1247 subjects with different HIV and TB status across 5 geographically diverse sites in Africa (South Africa, The Gambia, Ethiopia, Malawi and Uganda). We used a 7-day whole blood assay followed by IFN-γ ELISA on the supernatants. Antigens included PPD, ESAT-6 and Ag85B (dominant antigens) together with novel resuscitation-promoting factors (rpf), reactivation proteins, latency (Mtb DosR regulon-encoded) antigens, starvation-induced antigens and secreted antigens.
There was variation between sites in responses to the antigens, presumably due to underlying genetic and environmental differences. When results from all sites were combined, HIV- subjects with active TB showed significantly lower responses compared to both TST- and TST+ contacts to latency antigens (Rv0569, Rv1733, Rv1735, Rv1737) and the rpf Rv0867; whilst responses to ESAT-6/CFP-10 fusion protein (EC), PPD, Rv2029, TB10.3, and TB10.4 were significantly higher in TST+ contacts (LTBI) compared to TB and TST- contacts fewer differences were seen in subjects with HIV co-infection, with responses to the mitogen PHA significantly lower in subjects with active TB compared to those with LTBI and no difference with any antigen.
Our multi-site study design for testing novel Mtb antigens revealed promising antigens for future vaccine development. The IFN-γ ELISA is a cheap and useful tool for screening potential antigenicity in subjects with different ethnic backgrounds and across a spectrum of TB and HIV infection states. Analysis of cytokines other than IFN-γ is currently on-going to determine correlates of protection, which may be useful for vaccine efficacy trials.
When manifested as Mycobacterium tuberculosis (MTB) bacteremia, disseminated MTB infection clinically mimics other serious blood stream infections often hindering early diagnosis and initiation of potentially life-saving anti-tuberculosis therapy. In a cohort of hospitalized HIV-infected Ugandan patients with severe sepsis, we report the frequency, management and outcomes of patients with MTB bacteremia and propose a risk score based on clinical predictors of MTB bacteremia.
We prospectively enrolled adult patients with severe sepsis at two Ugandan hospitals and obtained blood cultures for MTB identification. Multivariable logistic regression modeling was used to determine predictors of MTB bacteremia and to inform the stratification of patients into MTB bacteremia risk categories based on relevant patient characteristics.
Among 368 HIV-infected patients with a syndrome of severe sepsis, eighty-six (23%) had MTB bacteremia. Patients with MTB bacteremia had a significantly lower median CD4 count (17 vs 64 lymphocytes/mm3, p<0.001) and a higher 30-day mortality (53% vs 32%, p = 0.001) than patients without MTB bacteremia. A minority of patients with MTB bacteremia underwent standard MTB diagnostic testing (24%) or received empiric anti-tuberculosis therapy (15%). Independent factors associated with MTB bacteremia included male sex, increased heart rate, low CD4 count, absence of highly active anti-retroviral therapy, chief complaint of fever, low serum sodium and low hemoglobin. A risk score derived from a model containing these independent predictors had good predictive accuracy [area under the curve = 0.85, 95% CI 0.80–0.89].
Nearly 1 in 4 adult HIV-infected patients hospitalized with severe sepsis in 2 Ugandan hospitals had MTB bacteremia. Among patients in whom MTB was suspected, standard tests for diagnosing pulmonary MTB were inaccurate for correctly classifying patients with or without bloodstream MTB infection. A MTB bacteremia risk score can improve early diagnosis of MTB bacteremia particularly in settings with increased HIV and MTB co-infection.
Dysglycemia during sepsis is associated with poor outcomes in resource-rich settings. In resource-limited settings, hypoglycemia is often diagnosed clinically without the benefit of laboratory support. We studied the utility of point-of-care glucose monitoring to predict mortality in severely septic patients in Uganda.
Prospective observational study.
One national and two regional referral hospitals in Uganda.
We enrolled 532 patients with sepsis at three hospitals in Uganda. The analysis included 418 patients from the three sites with inhospital mortality data, a documented admission blood glucose concentration, and evidence of organ dysfunction at admission (systolic blood pressure ≤100 mm Hg, lactate > 4 mmol/L, platelet number <100,000/µL, or altered mental status).
Measurements and Main Results
We evaluated the association between admission point-of-care blood glucose concentration and inhospital mortality. We also assessed the accuracy of altered mental status as a predictor of hypoglycemia. Euglycemia occurred in 33.5% (140 of 418) of patients, whereas 16.3% (68 of 418) of patients were hypoglycemic and 50.2% (210 of 418) were hyperglycemic. Univariate Cox regression analyses comparing inhospital mortality among hypoglycemic (35.3% [24 of 68], hazard ratio 2.0, 95% confidence interval 1.2–3.6, p = .013) and hyperglycemic (29.5% [62 of 210], hazard ratio 1.5, 95% confidence interval 0.96–2.4, p = .08) patients to euglycemic (19.3% [27 of 140]) patients showed statistically significantly higher rates of inhospital mortality for patients with hypoglycemia. Hypoglycemia (adjusted hazard ratio 1.9, 95% confidence interval 1.1–3.3, p = .03) remained significantly and independently associated with inhospital mortality in the multivariate model. The sensitivity and specificity of altered mental status for hypoglycemia were 25% and 86%, respectively.
Hypoglycemia is an independent risk factor for inhospital mortality in patients with severe sepsis and cannot be adequately assessed by clinical examination. Correction of hypoglycemia may improve outcomes of critically ill patients in resource-limited settings.
Africa; hypoglycemia; mortality; outcomes; severe sepsis; Uganda
The world health organization (WHO) declared tuberculosis (TB) a global emergency, mainly affecting people in sub-Saharan Africa. However there is little data about the burden of TB among adolescents. We estimated the prevalence and incidence of TB and assessed factors associated with TB among adolescents aged 12–18 years in a rural population in Uganda in order to prepare the site for phase III clinical trials with novel TB vaccines among adolescents.
In a prospective cohort study, we recruited 5000 adolescents and followed them actively, every 6 months, for 1–2 years. Participants suspected of having TB were those who had any of; TB signs and symptoms, history of TB contact or a positive tuberculin skin test (TST) of ≥10 mm. Laboratory investigations included sputum smear microscopy and culture.
Of the 5000 participants, eight culture confirmed cases of TB were found at baseline: a prevalence of 160/100,000 (95% confidence interval (CI), 69–315). There were 13 incident TB cases detected in an average of 1.1 person years: an incidence of 235/100,000 person years (95% CI, 125–402). None of the confirmed TB cases were HIV infected. Predictors for prevalent TB disease were: a history of TB contact and a cough ≥ 2 weeks at baseline and being out of school, while the only predictor for incident TB was a positive TST during follow-up.
The TB incidence among adolescents in this rural part of Uganda seemed too low for a phase III TB vaccine trial. However, the study site demonstrated capability to handle a large number of participants with minimal loss to follow-up and its suitability for future clinical trials. Improved contact tracing in TB program activities is likely to increase TB case detection among adolescents. Future studies should explore possible pockets of higher TB incidence in urban areas and among out of school youth.
Vitamin D deficiency has been reported among patients with tuberculosis in Africa despite abundant sunshine. Vitamin D plays a fundamental role in improving anti tuberculosis immunity, reducing progression and severity of TB in humans.
In this descriptive cross sectional study, 260 hospitalized adults with a confirmed diagnosis of TB were enrolled into the study from the pulmonology wards of Mulago national referral and teaching hospital, Uganda. The serum concentrations of 25-hydroxyvitamin D or 25 (OH) D were determined by an electrochemilumniscence immunoassay. Vitamin D deficiency, vitamin D insufficiency, severe and very severe vitamin D deficiency were defined as serum 25(OH) D concentrations of ≤ 20 ng/ml, 21–29 ng/ml, < 10 ng/ml and <5 ng/ml respectively.
Majority of the study participants were males (146, 56.2%) and < 35 years (154, 59.2%). The mean age ± SD was 34.7 ± 9.5 years. Two hundred eight (80%) patients were HIV co-infected with a median CD4 count of 68 cells/mm3 (IQR: 17–165). The prevalence of vitamin D deficiency, vitamin D insufficiency, severe and very severe vitamin D deficiency among the hospitalized adult tuberculosis patients was 44.2%, 23.5%, 13.5% and 4.2% respectively. The median (IQR) vitamin D concentration in ng/ml was 22.55 (14.59-33.31).
Vitamin D deficiency was more prevalent in patients with hypoalbuminemia (97.4%), anemia (86.1%), HIV co-infected patients with CD4 count <200cells/mm3 (83.2%) and hypocalcemia corrected for serum albumin levels (67%).
Vitamin D deficiency is very common among hospitalized adult tuberculosis patients in Uganda especially in patients with hypoalbuminemia, anemia, HIV co-infected patients with CD4 count <200cells/mm3 and hypocalcemia corrected for serum albumin levels.
Vitamin D deficiency; Tuberculosis; Uganda
In sub-Saharan Africa, sepsis is an important cause of mortality but optimal sepsis management including fluid resuscitation, early antibiotic administration and patient monitoring is limited by a lack of supplies and skilled health workers.
To evaluate whether early, monitored sepsis management provided by a study medical officer can improve survival among patients with severe sepsis admitted to two public hospitals in Uganda.
DESIGN, SETTING and PATIENTS
A prospective before and after study of an intervention cohort (n=426) with severe sepsis receiving early, monitored sepsis management compared to an observation cohort (n=245) of similarly ill patients with severe sepsis receiving standard management after admission to the medical wards of two Ugandan hospitals.
Early sepsis management provided by a dedicated study medical officer comprised of fluid resuscitation, early antibiotics and regular monitoring in the first 6 hours of hospitalization.
Kaplan-Meier survival and unadjusted and adjusted Cox proportional hazards analysis were used to compare the effect of early, monitored sepsis management on 30-day mortality between the intervention cohort (enrolled May 2008 to May 2009) and observation cohort (enrolled July 2006 to November 2006).
The majority (86%) of patients in both cohorts were HIV-infected. Median fluid volume provided in the first 6 hours of hospitalization was higher in intervention than observation cohort patients (3000 vs. 500 mL, p<0.001) and a greater proportion of intervention cohort patients received antibacterial therapy in less than one hour (67% vs 30.4%, p<0.001). Mortality at 30 days was significantly lower in the intervention cohort compared to the observation cohort (33.0% vs 45.7%, log-rank p=0.005). After adjustment for potential confounders, the hazard of 30-day mortality was 26% less in the intervention cohort compared to the observation cohort (adjusted HR=0.74, 95% CI=0.55–0.98). Mortality among the 13% of intervention patients who developed signs of respiratory distress was associated with baseline illness severity rather than fluid volume administered.
Early, monitored management of severely septic patients in Uganda improves survival and is feasible and safe even in a busy public referral hospital.
Sepsis; Management Bundle; Fluid Therapy; Uganda; Africa; Mortality; Pulmonary Edema