A Two-Faced Gut Microbiome: Butyrogenic and Proinflammatory Bacteria Predominate in the Intestinal Milieu of People Living with HIV from Western Mexico.

HIV infection results in marked alterations in the gut microbiota (GM), such as the loss of microbial diversity and different taxonomic and metabolic profiles. Despite antiretroviral therapy (ART) partially ablating gastrointestinal alterations, the taxonomic profile after successful new ART has shown wide variations. Our objective was to determine the GM composition and functions in people living with HIV (PLWHIV) under ART in comparison to seronegative controls (SC). Fecal samples from 21 subjects (treated with integrase strand-transfer inhibitors, INSTIs) and 18 SC were included. We employed 16S rRNA amplicon sequencing, coupled with PICRUSt2 and fecal short-chain fatty acid (SCFA) quantification by gas chromatography. The INSTI group showed a decreased α-diversity (p < 0.001) compared to the SC group, at the expense of increased amounts of Pseudomonadota (Proteobacteria), Segatella copri, Lactobacillus, and Gram-negative bacteria. Concurrently, we observed an enrichment in Megasphaera and Butyricicoccus, both SCFA-producing bacteria, and significant elevations in fecal butyrate in this group (p < 0.001). Interestingly, gut dysbiosis in PLWHIV was characterized by a proinflammatory environment orchestrated by Pseudomonadota and elevated levels of butyrate associated with bacterial metabolic pathways, as well as the evident presence of butyrogenic bacteria. The role of this unique GM in PLWHIV should be evaluated, as well as the use of butyrate-based supplements and ART regimens that contain succinate, such as tenofovir disoproxil succinate. This mixed profile is described for the first time in PLWHIV from Mexico.

Gut Bacterial Communities in HIV-Infected Individuals with Metabolic Syndrome: Effects of the Therapy with Integrase Strand Transfer Inhibitor-Based and Protease Inhibitor-Based Regimens.

Antiretroviral therapies (ART) are strongly associated with weight gain and metabolic syndrome (MetS) development in HIV-infected patients. Few studies have evaluated the association between gut microbiota and integrase strand transfer inhibitor (INSTI)-based and protease inhibitor (PI)-based regimens in HIV-infected patients with MetS. To assess this, fecal samples were obtained from HIV-infected patients treated with different regimens (16 PI + MetS or 30 INSTI + MetS) and 18 healthy controls (HCs). The microbial composition was characterized using 16S rRNA amplicon sequencing. The INSTI-based and PI-based regimens were associated with a significant decrease in α-diversity compared to HCs. The INSTI + MetS group showed the lowest α-diversity between both regimens. A significant increase in the abundance of short-chain fatty acid (SCFA)-producing genera (Roseburia, Dorea, Ruminococcus torques, and Coprococcus) was observed in the PI + MetS group, while Prevotella, Fusobacterium, and Succinivibrio were significantly increased in the INSTI + MetS group. Moreover, the Proteobacteria/Firmicutes ratio was overrepresented, and functional pathways related to the biosynthesis of LPS components were increased in the INSTI + MetS group. The gut microbiota of patients receiving INSTIs showed a more pronounced dysbiosis orchestrated by decreased bacterial richness and diversity, with an almost complete absence of SCFA-producing bacteria and alterations in gut microbiota functional pathways. These findings have not been previously observed.

Effect of antiretroviral therapy on decreasing arterial stiffness, metabolic profile, vascular and systemic inflammatory cytokines in treatment-naïve HIV: A one-year prospective study.

INTRODUCTION: Cardiovascular disease is a major cause of death among people living with HIV (PLH). Non-treated PLH show increased levels of inflammation and biomarkers of vascular activation, and arterial stiffness as a prognostic cardiovascular disease risk factor. We investigated the effect of one year of ART on treatment-naïve HIV(+) individuals on arterial stiffness and inflammatory and vascular cytokines. METHODS: We cross-sectionally compared aortic stiffness via tonometry, inflammatory, and vascular serum cytokines on treatment-naïve (n = 20) and HIV (-) (n = 9) matched by age, sex, metabolic profile, and Framingham score. We subsequently followed young, treatment-naïve individuals after 1-year of ART and compared aortic stiffness, metabolic profile, and inflammatory and vascular serum biomarkers to baseline. Inflammatory biomarkers included: hs-CRP, D-Dimer, SAA, sCD163s, MCP-1, IL-8, IL-18, MRP8/14. Vascular cytokines included: myoglobin, NGAL, MPO, Cystatin C, ICAM-1, VCAM-1, and MMP9. RESULTS: Treatment-naïve individuals were 34.8 years old, mostly males (95%), and with high smoking prevalence (70%). Baseline T CD4+ was 512±324 cells/mcL. cfPWV was similar between HIV(-) and treatment-naïve (6.8 vs 7.3 m/s; p = 0.16) but significantly decreased after ART (-0.52 m/s; 95% CI -0.87 to -0.16; p0.006). Almost all the determined cytokines were significantly higher compared to controls, except for MCP-1, myoglobin, NGAL, cystatin C, and MMP-9. At follow-up, only total cholesterol and triglycerides increased and all inflammatory cytokines significantly decreased. Regarding vascular cytokines, MPO, ICAM-1, and VCAM-1 showed a reduction. D-Dimer tended to decrease (p = 0.06) and hs-CRP did not show a significant reduction (p = 0.17). CONCLUSION: One year of ART had a positive effect on reducing inflammatory and vascular cytokines and arterial stiffness.

Oral Manifestations Associated with HIV/AIDS Patients.

Oral manifestations are early and important clinical indicators of Human Immunodeficiency Virus (HIV) infection since they can occur in up to 50% of HIV-infected patients and in up to 80% of patients at the AIDS stage (<200 CD4+ T lymphocytes). Oral health is related to physical and mental well-being because the presence of some lesions can compromise dental aesthetics, and alter speech, chewing, and swallowing, thus impacting the quality of life of patients. For this reason, it is necessary to integrate, as part of the medical treatment of HIV-positive patients, the prevention, diagnosis, and control of oral health. It is essential that health professionals have the power to identify, diagnose, and treat oral pathologies through clinical characteristics, etiological agents, and risk factors, both local and systemic. A diagnosis at an early stage of injury allows optimizing and prioritizing oral treatments, especially in acute pathologies, such as gingivitis and necrotizing periodontitis. In this group of patients, the development of strategies for the prevention, control, and reduction of these pathologies must be prioritized in order to reduce morbidity and mortality in this group of patients.

Escherichia/Shigella, SCFAs, and Metabolic Pathways-The Triad That Orchestrates Intestinal Dysbiosis in Patients with Decompensated Alcoholic Cirrhosis from Western Mexico.

Gut microbiota undergoes profound alterations in alcohol cirrhosis. Microbiota-derived products, e.g., short chain fatty acids (SCFA), regulate the homeostasis of the gut-liver axis. The objective was to evaluate the composition and functions of the intestinal microbiota in patients with alcohol-decompensated cirrhosis. Fecal samples of 18 patients and 18 healthy controls (HC) were obtained. Microbial composition was characterized by 16S rRNA amplicon sequencing, SCFA quantification was performed by gas chromatography (GC), and metagenomic predictive profiles were analyzed by PICRUSt2. Gut microbiota in the cirrhosis group revealed a significant increase in the pathogenic/pathobionts genera Escherichia/Shigella and Prevotella, a decrease in beneficial bacteria, such as Blautia, Faecalibacterium, and a decreased α-diversity (p < 0.001) compared to HC. Fecal SCFA concentrations were significantly reduced in the cirrhosis group (p < 0.001). PICRUSt2 analysis indicated a decrease in acetyl-CoA fermentation to butyrate, as well as an increase in pathways related to antibiotics resistance, and aromatic amino acid biosynthesis. These metabolic pathways have been poorly described in the progression of alcohol-related decompensated cirrhosis. The gut microbiota of these patients possesses a pathogenic/inflammatory environment; therefore, future strategies to balance intestinal dysbiosis should be implemented. These findings are described for the first time in the population of western Mexico.

In vitro Azole antifungals susceptibility of Candida spp. isolates from HIV-infected patients with periodontitis.

OBJECTIVE: The objective of the present study was to determine the in vitro Azole antifungals susceptibility of Candida spp. strains isolated from HIV-positive patients with periodontitis. METHODS: Oral examination was performed in 500 HIV-positive patients, of which 228 were included in the study for having periodontitis which and separated in two groups based on their TCD4+ T-cells: (A) n = 110 (≤200 CD4+); (B) n = 118 (>200 CD4+). Candida spp. were isolated from the subgingival biofilm and crevicular fluid by seeding on CHROMagar plates and confirmed by endpoint PCR and MALDI-TOF. The susceptibility test in vitro for five antifungals was performed using the disc diffusion method. RESULTS: From the 228 HIV-positive patients with periodontitis, 174 were positive to Candida spp., and 204 isolations were obtained. 138 (67.64%) were C. albicans, and 66 (32.35%) were Candida non-albicans species. The most frequent Candida non-albicans species in order of frequency were C. glabrata with 48 (23.52%), C. tropicalis with 10 (4.9%), C. krusei with 7 (3.43%), and C. dubliniensis with 1 (0.49%). All species presented resistance to any antifungal: 149 to 5-fluorocytosine (73.0%), 149 to fluconazole (73.0%), and 144 to voriconazole (70.7%). Miconazole and econazole presented the highest susceptibility rates with 129 (63.2%) and 130 (63.7%) isolations, respectively. CONCLUSION: The Candida spp. involved in periodontitis of HIV-positive patients have a multi-resistant feature. It is necessary to implement recurrent research regarding the antifungal resistance of the Candida spp. that take part in periodontitis pathogenesis to promote an effective treatment in HIV patients.

Clinical features associated with neurosyphilis in people living with HIV and late latent syphilis.

BACKGROUND: The diagnosis of neurosyphilis is a challenge, and the criteria for deciding when to perform a lumbar puncture are still controversial, especially in people living with HIV with a late latent syphilis diagnosis. METHODS: Retrospective analysis of demographic, clinical, and laboratory data of people with HIV and documented late latent syphilis or syphilis of unknown duration with a cerebrospinal fluid VDRL test. RESULTS: 122 patients were evaluated, of whom 52 had the diagnosis of neurosyphilis. Patients with and without neurosyphilis presented a similar viral load and lymphocyte CD4+ T-cell count. Neurological symptoms (OR 6.4, 95% CI 2.1-22.4; p < 0.01), serum VDRL titers of 1:32 (p<0.01), 1:64 (p = 0.055), and ≥1:128 (p < 0.001) were associated with neurosyphilis. Furthermore, serum VDRL ≥1:32 were associated with (OR 24.9, 95% CI 5.45-154.9; p < 0.001) or without (OR 6.5, 95% CI 2.0-29.2; p = 0.004) neurological symptoms with neurosyphilis; however, VDRL ≤1:16 with neurological symptoms can be associated with neurosyphilis (OR 7.6, 95% CI 1.03-64.3; p = 0.046). CONCLUSION: Neurological symptoms, particularly headache, were predictors of neurosyphilis in people with HIV irrespective of their viral load and lymphocyte CD4+ T-cell count in late latent syphilis. A serum VDRL ≥1:32 increased the risk of neurosyphilis in patients with or without any symptoms.

Diagnostic accuracy of antigen detection in urine and molecular assays testing in different clinical samples for the diagnosis of progressive disseminated histoplasmosis in patients living with HIV/AIDS: A prospective multicenter study in Mexico.

BACKGROUND: The progressive disseminated histoplasmosis (PDH) has been associated with severe disease and high risk of death among people living with HIV (PLWHIV). Therefore, the purpose of this multicenter, prospective, double-blinded study done in ten Mexican hospitals was to determine the diagnostic accuracy of detecting Histoplasma capsulatum antigen in urine using the IMMY ALPHA Histoplasma EIA kit (IAHE), clarus Histoplasma GM Enzyme Immunoassay (cHGEI IMMY) and MiraVista Histoplasma Urine Antigen LFA (MVHUALFA); as well as the Hcp100 and 1281-1283220SCAR nested PCRs in blood, bone-marrow, tissue biopsies and urine. METHODOLOGY/PRINCIPAL FINDINGS: We included 415 PLWHIV older than 18 years of age with suspicion of PDH. Using as diagnostic standard recovery of H. capsulatum in blood, bone marrow or tissue cultures, or histopathological exam compatible, detected 108 patients (26%, [95%CI, 21.78-30.22]) with proven-PDH. We analyzed 391 urine samples by the IAHE, cHGEI IMMY and MVHUALFA; the sensitivity/specificity values obtained were 67.3% (95% CI, 57.4-76.2) / 96.2% (95% CI, 93.2-98.0) for IAHE, 91.3% (95% CI, 84.2-96.0) / 90.9% (95% CI, 87.0-94.0) for cHGEI IMMY and 90.4% (95% CI, 83.0-95.3) / 92.3% (95% CI, 88.6-95.1) for MVHUALFA. The Hcp100 nested PCR was performed on 393, 343, 75 and 297, blood, bone marrow, tissue and urine samples respectively; the sensitivity/specificity values obtained were 62.9% (95%CI, 53.3-72.5)/ 89.5% (95%CI, 86.0-93.0), 65.9% (95%CI, 56.0-75.8)/ 89.0% (95%CI, 85.2-92.9), 62.1% (95%CI, 44.4-79.7)/ 82.6% (95%CI, 71.7-93.6) and 34.9% (95%CI, 24.8-46.2)/ 67.3% (95%CI, 60.6-73.5) respectively; and 1281-1283220SCAR nested PCR was performed on 392, 344, 75 and 291, respectively; the sensitivity/specificity values obtained were 65.3% (95% CI, 55.9-74.7)/ 58.8% (95%CI, 53.2-64.5), 70.8% (95%CI, 61.3-80.2)/ 52.9% (95%CI, 46.8-59.1), 71.4% (95%CI, 54.7-88.2)/ 40.4% (95%CI, 26.4-54.5) and 18.1% (95%CI, 10.5-28.1)/ 90.4% (95%CI, 85.5-94.0), respectively. CONCLUSIONS/SIGNIFICANCE: The cHGEI IMMY and MVHUALFA tests showed excellent performance for the diagnosis of PDH in PLWHIV. The integration of these tests in clinical laboratories will certainly impact on early diagnosis and treatment.

ZBTB gene expression in HIV patients: a possible new molecular mechanism of viral control.

HIV infects its target cell and integrates into its genome as an essential step in its replication cycle. Proviral DNA is also subjected to the same transcriptional regulation as the host cell genome by its own transcriptional factors, with activating or repressive activity. There is a clear interaction between the presence of transcriptional repressors and a decrease in the rate of HIV replication, promoting gene silencing in infected cells, which serve as viral reservoirs. This represents a major obstacle for HIV eradication. The ZBTB gene family comprises 49 genes that encode transcription factors that have a repressor function in differentiation and development of cells of the lymphopoietic lineage, including the main target cells of HIV, CD4+ T cells. In this cross-sectional study, we evaluated the expression profile of ZBTB genes in CD4+ T cells of HIV-positive individuals with different levels of infection control. We found upregulation of gene expression of ZBTB4 (p < 0.01), ZBTB7B (p < 0.001), and ZBTB38 (p < 0.05) and downregulation of ZBTB16 (p < 0.01) in HIV-positive patients compared to HIV-negative individuals. Interestingly, in a deeper analysis, we observed that elite controllers had the highest levels of expression of the ZBTB38, ZBTB2, HIC1, ZBTB7A, ZBTB7B (ThPOK) and ZBTB4 genes, showing 2.56- to 7.60-fold upregulation compare to the ART-naïve group. These results suggest a possible contribution of these ZBTB transcriptional repressors in HIV-positive patients and a possible new molecular mechanism of viral control.

Aortic stiffness and central hemodynamics in treatment-naïve HIV infection: a cross-sectional study.

BACKGROUND: Human immunodeficiency virus (HIV) infection is associated with a greater risk of cardiovascular disease (CVD). HIV infection causes a chronic inflammatory state and increases oxidative stress which can cause endothelial dysfunction and arterial stiffness. Aortic stiffness measured by carotid femoral-pulse wave velocity (cfPWV) and central hemodynamics are independent cardiovascular risk factors and have the prognostic ability for CVD. We assessed cfPWV and central hemodynamics in young individuals with recent HIV infection diagnosis and without antiretroviral therapy. We hypothesized that individuals living with HIV would present greater cfPWV and central hemodynamics (central systolic blood pressure and pulse pressure) compared to uninfected controls. METHODS: We recruited 51 treatment-naïve individuals living with HIV (HIV(+)) without previous CVD and 51 age- and sex-matched controls (HIV negative (-)). We evaluated traditional CVD risk factors including metabolic profile, blood pressure (BP), smoking, HIV viral load, and CD4+ T-cells count. Arterial stiffness and central hemodynamics were evaluated by cfPWV, central systolic BP, and central pulse pressure (cPP) via applanation tonometry. RESULTS: HIV(+) individuals presented a greater prevalence of smoking, reduced high-density lipoprotein cholesterol, and body mass index. 65.9% of HIV(+) individuals exhibited lymphocyte CD4+ T-cells count < 500 cells/µL. There was no difference in brachial or central BP between groups; however, HIV(+) individuals showed significantly lower cPP. We observed a greater cfPWV (mean difference = 0.5 m/s; p < 0.01) in HIV(+) compared to controls, even after adjusting for heart rate, mean arterial pressure and smoking. CONCLUSION: In the early stages of infection, non-treated HIV individuals present a greater prevalence of traditional CVD risk factors, arterial stiffness, and normal or in some cases central hemodynamics.

Microbiome alterations are related to an imbalance of immune response and bacterial translocation in BDL-rats.

OBJECTIVES: Bacterial translocation in patients with cirrhosis is an important triggering factor for infections and mortality. In the bile duct ligation (BDL) model, crucial players of bacterial translocation are still unknown. This study aims to determine the interrelation between microbiome composition in the colon, mesenteric lymph nodes, and liver, as well as the local inflammatory microenvironment in the BDL model. MATERIALS AND METHODS: Liver damage was assayed by Masson trichrome staining, and hepatic enzymes. The diversity of microbiota in colon stools, mesenteric lymph nodes, and liver was determined by 16S rRNA pyrosequencing. Cytokine expression in mesenteric lymph nodes was analyzed by qRT-PCR. RESULTS: Our results show that Proteobacteria was the predominant phylum found to translocate to mesenteric lymph nodes and liver in cirrhotic rats. Bile duct ligation induces a drastic intestinal dysbiosis, revealed by an increased relative abundance of Sarcina, Clostridium, Helicobacter, Turicibacter, and Streptococcus genera. However, beneficial bacteria, such as Lactobacillus, Prevotella and Ruminococcus were found to be notably decreased in BDL groups. Mesenteric pro-inflammatory (TNF-α, IL-1ß, IL-6, TLR-4) and regulatory (TGF-ß, Foxp3, and IL-10) molecules at 30 days post-BDL were significantly increased. Conversely, TGF-ß and Foxp3 were significantly augmented at 8 days post-BDL. CONCLUSION: Dysbiosis in the colon and mesenteric lymph nodes is linked to an imbalance in the immune response; therefore, this may be an important trigger for bacterial translocation in the BDL model.

Diagnostic accuracy cohort study and clinical value of the Histoplasma urine antigen (ALPHA Histoplasma EIA) for disseminated histoplasmosis among HIV infected patients: A multicenter study.

BACKGROUND: The Histoplasma urine antigen (HUAg) is the preferred method to diagnose progressive disseminated histoplasmosis (PDH) in HIV patients. In 2007, IMMY ALPHA Histoplasma EIA was approved for clinical for on-site use, and therefore useful for regions outside the United States. However, ALPHA-HUAg is considered inferior to the MVista-HUAg which is only available on referral. We aim to evaluate the diagnostic accuracy of ALPHA-HUAg. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a multicenter, prospective, diagnostic test study in two secondary and eight tertiary-care facilities in Mexico. We included HIV patient with PDH suspicion and evaluated ALPHA-HUAg diagnostic accuracy using as reference standard the Histoplasma capsulatum growth on blood, bone marrow, and tissue cultures or compatible histopathologic exam (PDH-proven). We evaluated the results of 288 patients, 29.5% (85/288; 95% confidence interval [CI], 24.3-35.1) had PDH. The sensitivity of ALPHA-HUAg was 67.1% (95% CI, 56-76.8%) and the specificity was 97.5% (95% CI, 94.3%-99.1%). The positive likelihood ratio was 27.2 (95% CI; 11.6-74.4). In 10.5% of the PDH-proven patients, a co-existing opportunistic infection was diagnosed, mostly disseminated Mycobacterium avium complex infection. CONCLUSIONS/SIGNIFICANCE: We observed a high specificity but low sensitivity of IMMY-HUAg. The test may be useful to start early antifungals, but a culture-based approach is necessary since co-infections are frequent and a negative IMMY-HUAg result does not rule out PDH.

Follicular CD8 T cells accumulate in HIV infection and can kill infected cells in vitro via bispecific antibodies.

Cytolytic CD8 T cells play a crucial role in the control and elimination of virus-infected cells and are a major focus of HIV cure efforts. However, it has been shown that HIV-specific CD8 T cells are infrequently found within germinal centers (GCs), a predominant site of active and latent HIV infection. We demonstrate that HIV infection induces marked changes in the phenotype, frequency, and localization of CD8 T cells within the lymph node (LN). Significantly increased frequencies of CD8 T cells in the B cell follicles and GCs were found in LNs from treated and untreated HIV-infected individuals. This profile was associated with persistent local immune activation but did not appear to be directly related to local viral replication. Follicular CD8 (fCD8) T cells, despite compromised cytokine polyfunctionality, showed good cytolytic potential characterized by high ex vivo expression of granzyme B and perforin. We used an anti-HIV/anti-CD3 bispecific antibody in a redirected killing assay and found that fCD8 T cells had better killing activity than did non-fCD8 T cells. Our results indicate that CD8 T cells with potent cytolytic activity are recruited to GCs during HIV infection and, if appropriately redirected to kill HIV-infected cells, could be an effective component of an HIV cure strategy.

Rectal Plasmablastic Lymphoma in HIV/AIDS: Two Cases.

Plasmablastic lymphoma is an aggressive variant of large B-cells lymphoma in which the infection by Human Immunodeficiency Virus and Epstein-Barr herpesvirus are involved. This recently denominated neoplasia has a special tropism through the oral cavity. However, its presence has been reported in the digestive tract, abdominal cavity and retroperitoneum. We describe two Human Immunodeficiency Virus infected patient cases with rectal presentation of PL in the HIV service of the Hospital Civil de Guadalajara.