Sex and HIV Differences in Preserved Ratio Impaired Spirometry (PRISm) Among Ugandans Postpneumonia.

Background: Preserved ratio impaired spirometry (PRISm), defined as a normal ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (≥0.70) with low FEV1 (<80% predicted), has been associated with increased mortality in the general population. Female sex has been associated with increased odds of PRISm in people without HIV. People with HIV (PWH) are at increased risk for lung function abnormalities, but whether HIV modifies the effect of sex on PRISm development is largely unknown. Methods: Adults with and without HIV underwent baseline followed by serial spirometry after completing therapy for pneumonia, predominantly tuberculosis (TB), in Kampala, Uganda. Using generalized estimating equations adjusted for age, body mass index, smoking, biomass fuel exposure, HIV, and TB status, we compared individuals with PRISm with those with normal spirometry. These models were stratified by HIV status. Results: Of 339 baseline participants, 153 (45%) were women; 129 (38%) had HIV, of whom 53% were women. Overall, 105/339 participants (31%) had PRISm at baseline. HIV was associated with lower odds of PRISm (adjusted odds ratio [aOR], 0.38; 95% CI, 0.21-0.68; P = .001). Female sex trended toward increased odds of PRISm among all participants (aOR, 1.65; 95% CI, 0.99-2.75; P = .052). The association between female sex and PRISm tended to be stronger among PWH (aOR, 3.16; 95% CI, 1.14-8.76; P = .03) than among those without HIV (aOR, 1.34; 95% CI, 0.73-2.45; P = .34); this study was underpowered to detect an HIV-sex interaction of this magnitude (P = .30). Conclusions: Among Ugandan adults who recovered from pneumonia, female sex was associated with increased odds and HIV with decreased odds of PRISm, suggesting independent sex and HIV effects on PRISm pathogenesis.

Sex modifies the risk of HIV-associated obstructive lung disease in Ugandans postpneumonia.

OBJECTIVES: Spirometric abnormalities are frequent, and obstructive lung disease (OLD) is a common comorbidity among people with HIV (PWH). HIV increases the risk of many comorbidities to a greater degree in women than in men. Few studies have evaluated whether sex modifies the HIV-associated risk of OLD. DESIGN AND METHODS: To evaluate the associations between sex and HIV with abnormal lung function, women and men with and without HIV underwent spirometric testing after completing therapy for pneumonia, including tuberculosis (TB), in Kampala, Uganda. OLD was defined as a postbronchodilator forced expiratory volume in the first second to forced vital capacity (FEV 1 /FVC) ratio less than 0.70. Associations between sex, HIV, and lung function were evaluated using multivariable regression models including sex-by-HIV interaction terms after adjusting for age, BMI, smoking status, and TB status. RESULTS: Among 348 participants, 147 (42%) were women and 135 (39%) were HIV-positive. Sixteen (11%) women and 23 men (11%) had OLD. The HIV-sex interaction was significant for obstructive lung disease ( P  = 0.04). In the adjusted stratified analysis, women with HIV had 3.44 (95% CI 1.11-12.0; P  = 0.04) increased odds of having OLD compared with men with HIV. Women without HIV did not have increased odds of having OLD compared with men without HIV. CONCLUSION: HIV appears to increase the risk of OLD to a greater degree in women than in men in an urban Ugandan setting. The mechanistic explanation for this interaction by sex remains unclear and warrants further study.

Feasibility and Sensitivity of Saliva GeneXpert MTB/RIF Ultra for Tuberculosis Diagnosis in Adults in Uganda.

The objective of this prospective observational study carried out at China-Uganda Friendship Hospital-Naguru in Kampala, Uganda, was to determine the performance of GeneXpert MTB/RIF Ultra (Xpert Ultra) molecular testing on saliva for active tuberculosis (TB) disease among consecutive adults undergoing TB diagnostic evaluation who were Xpert Ultra positive on sputum. We calculated sensitivity to determine TB diagnostic performance in comparison to a composite reference standard of Mycobacterium tuberculosis liquid and solid cultures on two spot sputum specimens. Xpert Ultra on a single saliva sample had a sensitivity of 90% (95% confidence interval [CI], 81 to 95%) relative to the composite sputum culture-based reference standard, similar to the composite sensitivity of 87% (95% CI, 77 to 94%) for fluorescence microscopy (FM) for acid-fast bacilli on two sputum smears. The sensitivity of salivary Xpert Ultra was 24% lower (95% CI for difference, 2 to 48%; P = 0.003) among persons living with HIV (71%; 95% CI, 44 to 90%) than among persons living without HIV (95%; 95% CI, 86 to 99%) and 46% higher (95% CI, 14 to 77%; P < 0.0001) among FM-positive (96%; 95% CI, 87 to 99%) than among FM-negative (50%; 95% CI, 19 to 81%) patients. The semiquantitative Xpert Ultra grade was systematically higher in sputum than in a paired saliva sample from the same patient. In conclusion, molecular testing of saliva for active TB diagnosis was feasible and almost as sensitive as molecular testing of sputum in a high TB burden setting. IMPORTANCE Tuberculosis is among the leading causes of morbidity and mortality worldwide, in large part because >3 million people go undiagnosed and untreated each year. Sputum has been the mainstay for TB diagnosis for over a century but can be difficult for patients to produce. In addition, the vigorous coughing required during sputum collection can lead to infection of nearby individuals and health workers. In this case-only study, applying the ultra-sensitive GeneXpert MTB/RIF Ultra molecular diagnostic assay to saliva detected 90% of culture-confirmed TB cases among 81 adults who were undergoing TB evaluation at the outpatient department of a general hospital in Uganda and tested sputum GeneXpert MTB/RIF Ultra positive. These results suggest that saliva may be a feasible and sensitive alternative to sputum for TB diagnosis, thereby meeting two key metrics proposed by the World Health Organization in its target performance profile for a nonsputum test for TB.

Accuracy of GenoQuick MTB test in detection of Mycobacterium tuberculosis in sputum from TB presumptive patients in Uganda.

Objective: The objective of the study was to determine the diagnostic performance of the GenoQuick MTB test on heated sputum against the conventional Lowenstein-Jensen Mycobacterium tuberculosis culture as the reference method for tuberculosis diagnosis. Introduction: Fast, reliable, and easy-to-use tests for tuberculosis diagnosis are essential to achieving the Sustainable Development Goal of diagnosing and treating 90% of tuberculosis patients by 2030. We evaluated the diagnostic performance of the GenoQuick MTB, a polymerase chain reaction-lateral flow test, in Uganda, a resource-constrained, high tuberculosis- and HIV-burden setting. Methods: Fresh sputum samples from presumptive tuberculosis patients at Mulago Hospital were tested for M. tuberculosis using smear microscopy, GenoQuick MTB test, and Lowenstein-Jensen culture. For the GenoQuick MTB test, mycobacterial DNA was extracted by heating sputum at 95°C for 30 min while DNA amplification and detection were done following the manufacturer's protocol (Hain Lifescience, Nehren, Germany). Sensitivity, specificity, and kappa agreements were calculated against Lowenstein-Jensen M. tuberculosis culture as a reference test using STATA V12. Results: Of the 86 tested samples, 30.2% had culture-confirmed pulmonary tuberculosis. Overall, sensitivity was higher for GenoQuick MTB (81%, 95% confidence interval: 60%-93%) than for smear microscopy (69%, 95% confidence interval: 48%-86%). Among people living with HIV, sensitivity was identical for GenoQuick MTB and smear tests (75%, 95% confidence interval: 42%-95%). Contrastingly, smear had a higher overall specificity (98%, 95% confidence interval: 91%-100%) than for GenoQuick MTB (92%, 95% confidence interval: 81%-97%). A similar trend of specificity was observed among the people living with HIV for smear microscopy (100%, 95% CI: 87%-100%) and for GenoQuick MTB (96%, 95% confidence interval: 81%-100%). Conclusion: The GenoQuick MTB test could be a potential tuberculosis diagnostic test given its higher sensitivity. Evaluation of this test in larger studies is recommended.

Pneumonia surveillance with culture-independent metatranscriptomics in HIV-positive adults in Uganda: a cross-sectional study.

BACKGROUND: Pneumonia is a leading cause of death worldwide and is a major health-care challenge in people living with HIV. Despite this, the causes of pneumonia in this population remain poorly understood. We aimed to assess the feasibility of metatranscriptomics for epidemiological surveillance of pneumonia in patients with HIV in Uganda. METHODS: We performed a retrospective observational study in patients with HIV who were admitted to Mulago Hospital, Kampala, Uganda between Oct 1, 2009, and Dec 31, 2011. Inclusion criteria were age 18 years or older, HIV-positivity, and clinically diagnosed pneumonia. Exclusion criteria were contraindication to bronchoscopy or an existing diagnosis of tuberculosis. Bronchoalveolar lavage fluid was collected within 72 h of admission and a combination of RNA sequencing and Mycobacterium tuberculosis culture plus PCR were performed. The primary outcome was detection of an established or possible respiratory pathogen in the total study population. FINDINGS: We consecutively enrolled 217 patients during the study period. A potential microbial cause for pneumonia was identified in 211 (97%) patients. At least one microorganism of established respiratory pathogenicity was identified in 113 (52%) patients, and a microbe of possible pathogenicity was identified in an additional 98 (45%). M tuberculosis was the most commonly identified established pathogen (35 [16%] patients; in whom bacterial or viral co-infections were identified in 13 [37%]). Streptococcus mitis, although not previously reported as a cause of pneumonia in patients with HIV, was the most commonly identified bacterial organism (37 [17%] patients). Haemophilus influenzae was the most commonly identified established bacterial pathogen (20 [9%] patients). Pneumocystis jirovecii was only identified in patients with a CD4 count of less than 200 cells per mL. INTERPRETATION: We show the feasibility of using metatranscriptomics for epidemiologic surveillance of pneumonia by describing the spectrum of respiratory pathogens in adults with HIV in Uganda. Applying these methods to a contemporary cohort could enable broad assessment of changes in pneumonia aetiology following the emergence of SARS-CoV-2. FUNDING: US National Institutes of Health, Chan Zuckerberg Biohub.

High Mycobacterium tuberculosis Bacillary Loads Detected by Tuberculosis Molecular Bacterial Load Assay in Patient Stool: a Potential Alternative for Nonsputum Diagnosis and Treatment Response Monitoring of Tuberculosis.

Not all patients produce sputum, yet most available TB tests use sputum. We investigated the utility of a novel RNA-based quantitative test, the tuberculosis molecular bacterial load assay (TB-MBLA), for the detection and quantification of Mycobacterium tuberculosis in stool. Stools from 100 adult individuals were treated with OMNIgene-sputum reagent and tested using Xpert MTB/RIF ultra (Xpert ultra), auramine O smear microscopy (smear), mycobacterial growth indicator tube (MGIT), and Lowenstein-Jensen (LJ) cultures. The remaining portions were frozen at -20°C and later tested by TB-MBLA. MGIT sputum culture was used as a TB confirmatory test and reference for stool tests. Sixty-one of 100 participants were already confirmed TB positive by MGIT sputum culture, 20 (33%) of whom were HIV coinfected. TB-MBLA detected M. tuberculosis in 57/100 stool samples, including 49 already confirmed for TB. The mean bacterial load measured by stool TB-MBLA was 5.67 ± 1.7 log10 estimated CFU (eCFU) per mL in HIV-coinfected participants, which was higher than the 4.83 ± 1.59 log10 eCFU per mL among the HIV-negative participants (P = 0.04). The sensitivities (95% confidence intervals [CI]) of stool assays were 80% (68 to 89) and 90% (79 to 98) for TB-MBLA and Xpert ultra, which were both higher than the 44% (32 to 58), 64% (51 to 76), and 62% (45 to 77) for smear, MGIT, and Lowenstein-Jensen (LJ) stool cultures, respectively. The specificity (95% CI) of stool assays was highest for smear, at 97% (87 to 100), followed by Xpert ultra at 91% (76 to 98), TB-MBLA at 79% (63 to 90), LJ at 80% (64 to 91), and MGIT at 62% (45 to 77). Twenty-six percent of MGIT and 21% of LJ stool cultures were indeterminate due to contamination. Detection and quantification of viable M. tuberculosis bacilli in stool raises its utility as an alternative to sputum as a sample type for TB diagnosis. IMPORTANCE This paper highlights the value of stool as a sample type for diagnosis of tuberculosis. While other studies have used DNA-based assays like the Xpert MTB/RIF and culture to detect Mycobacterium tuberculosis in stool, this is the first study that has applied TB-MBLA, an RNA-based assay, to quantify TB bacteria in stool. The high microbial density and diversity in stool compromises the specificity and sensitivity of culture-based tests due to overgrowth of non-M. tuberculosis flora. Consequently, TB-MBLA becomes the most sensitive and specific test for the detection and quantification of viable TB bacteria in stool. Most crucially, this study raises the possibility of a nonsputum alternative sample type for diagnosis of TB among people who have difficulty in producing sputum.

Association between common telomere length genetic variants and telomere length in an African population and impacts of HIV and TB.

Prior studies in predominantly European (Caucasian) populations have discovered common genetic variants (single nucleotide polymorphisms, SNPs) associated with leukocyte telomere length (LTL), but whether these same variants affect LTL in non-Caucasian populations are largely unknown. We investigated whether six genetic variants previously associated with LTL (TERC (rs10936599), TERT (rs2736100), NAF1 (7675998), OBFC1 (rs9420907), ZNF208 (rs8105767), and RTEL1 (rs755017)) are correlated with telomere length (TL) in peripheral blood mononuclear cells (PBMCs) in a cohort of Africans living with and without HIV and undergoing evaluation for tuberculosis (TB). We found OBFC1 and the genetic sum score of the effect alleles across all six loci to be associated with shorter TL (adjusted for age, gender, HIV status, and smoking pack-years (p < 0.02 for both OBFC1 and the genetic sum score). In an analysis stratified by HIV status, the genetic sum score is associated with LTL in both groups with and without HIV. On the contrary, a stratified analysis according to TB status revealed that in the TB-positive subgroup, the genetic sum score is not associated with LTL, whereas the relationship remains in the TB-negative subgroup. The different impacts of HIV and TB on the association between the genetic sum score and LTL indicate different modes of modification and suggest that the results found in this cohort with HIV and TB participants may not be applied to the African general population. Future studies need to carefully consider these confounding factors.

Predictors of Mortality Among Hospitalized Patients With Lower Respiratory Tract Infections in a High HIV Burden Setting.

INTRODUCTION: Lower respiratory tract infections (LRTIs) are a leading cause of mortality in sub-Saharan Africa. Triaging identifies patients at high risk of death, but laboratory tests proposed for use in severity-of-illness scores are not readily available, limiting their clinical use. Our objective was to determine whether baseline characteristics in hospitalized participants with LRTI predicted increased risk of death. METHODS: This was a secondary analysis from the Mulago Inpatient Non-invasive Diagnosis-International HIV-associated Opportunistic Pneumonias (MIND-IHOP) cohort of adults hospitalized with LRTI who underwent standardized investigations and treatment. The primary outcome was all-cause mortality at 2 months. Predictors of mortality were determined using multiple logistic regression. RESULTS: Of 1887 hospitalized participants with LRTI, 372 (19.7%) died. The median participant age was 34.3 years (interquartile range, 28.0-43.3 years), 978 (51.8%) were men, and 1192 (63.2%) were HIV-positive with median CD4 counts of 81 cells/µL (interquartile range, 21-226 cells/µL). Seven hundred eleven (37.7%) participants had a microbiologically confirmed diagnosis. Temperature <35.5°C [adjusted odds ratio (aOR) = 1.77, 95% confidence intervals (CI): 1.20 to 2.60; P = 0.004], heart rate >120/min (aOR = 1.82, 95% CI: 1.37 to 2.43; P < 0.0001), oxygen saturation <90% (aOR = 2.74, 95% CI: 1.97 to 3.81; P < 0.0001), being bed-bound (aOR = 1.88, 95% CI: 1.47 to 2.41; P < 0.0001), and being HIV-positive (aOR = 1.49, 95% CI: 1.14 to 1.94; P = 0.003) were independently associated with mortality at 2 months. CONCLUSIONS: Having temperature <35.5°C, heart rate >120/min, hypoxia, being HIV-positive, and bed-bound independently predicts mortality in participants hospitalized with LRTI. These readily available characteristics could be used to triage patients with LRTI in low-income settings. Providing adequate oxygen, adequate intravenous fluids, and early antiretroviral therapy (in people living with HIV/AIDS) may be life-saving in hospitalized patients with LRTI.

Effect of anti-retroviral therapy on oxidative stress in hospitalized HIV-infected adults with and without TB.

BACKGROUND: HIV infection and opportunistic infections cause oxidative stress (OS), which is associated with tissue damage. Anti-retroviral therapy (ART) is used to treat HIV and decrease the risk of opportunistic infections, but it is unclear whether ART reduces OS. Association of ART with OS was investigated. METHODS: We stratified a convenience sample of frozen serum or plasma from HIV-infected, ART-naïve (n=21); HIV-infected, ART-treated (n=14); HIV and PTB co-infected, ART-naïve (n=21); HIV and PTB co-infected, ART-treated (n=25) patients. Controls (n=21) were HIV-negative adults without TB symptoms. Concentration of OS markers namely: transaminases (ALT and AST), gamma glutamyl transpeptidase (GGT), albumin, total protein, malondialdehyde (MDA), vitamin C, and total anti-oxidant status (TAS) were determined. RESULTS: AST (p<0.001), GGT (p<0.001), total protein (p=0.001) and MDA (p<0.001) were higher in HIV patients compared to controls. Vitamin C (P<0.0001) and albumin (p<0.01) were lower in HIV-patients relative to controls. ART was only associated with higher albumin (p=0.001), higher GGT (p=0.02) and lower vitamin C (p=0.009). HIV and PTB co-infection was only significantly associated with higher GGT (p=0.01) and AST (p=0.03). CONCLUSION: We identified severe OS among HIV-patients. ART was associated with both increased and reduced markers of OS hence suggesting that ART may not attenuate OS.