Clinical and immunologic predictors of death after an acute opportunistic infection: results from ACTG A5164

Admission C-Reactive Protein-to-Albumin Ratio Predicts the 180-Day Mortality of AIDS-Related Pneumocystis Pneumonia

Assessment tools are necessary for the adequate stratification of patients with AIDS-related pneumocystis pneumonia (PCP). The aim of this study was to evaluate the ability of severity assessment scores and inflammation- and nutrition-based parameters for predicting the 180-day mortality of AIDS-related PCP. This was a retrospective cohort study of patients with AIDS-related PCP admitted at the Beijing Di-Tan Hospital. The CURB-65 score, Pneumonia Severity Index (PSI) score, Acute Physiology And Chronic Health Evaluation II (APACHE II) score, C-reactive protein-to-albumin ratio (CAR), procalcitonin, neutrophil-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, and platelet-to-lymphocyte ratio during the first 24 h of intensive care unit admission were analyzed. The prognostic values of the severity assessment scores and biomarkers for 180-day mortality were evaluated using receiver operating characteristic (ROC) curves and integrated discrimination improvement (IDI) indexes. A total of 123 patients with AIDS-related PCP were included. Fifty-five patients were dead, and 68 were still alive at 180 days after admission. CAR, CURB-65, PSI, and APACHE II were independent predictors of 180-day mortality. The optimal cutoff value of CAR was 2.0 mg/g [area under the ROC curve = 0.844, 95% credential interval (CI) = 0.776-0.913], and CAR >2.0 mg/g increased the prognostic value of all three severity assessment scores, with an IDI index of 5.1% for the CURB-65 score, 8.1% for the PSI score, and 4.1% for the APACHE II score (all p < .05). Combining CAR >2.0 mg/g enhanced the capability of CURB-65, APACHE II, and PSI in predicting the 180-day mortality of patients with AIDS-related PCP.

A Model to Predict In-Hospital Mortality in HIV/AIDS Patients with Pneumocystis Pneumonia in China: The Clinical Practice in Real World

We aimed to develop and validate a predictive model to evaluate in-hospital mortality risk in HIV/AIDS patients with PCP in China. 1001 HIV/AIDS patients with PCP admitted in the Beijing Ditan hospital from August 2009 to January 2018 were included in this study. Multivariate Cox proportional hazard model was used to identify independent risk factors of death, and a predictive model was devised based on risk factors. The overall in-hospital mortality was 17.3%. The patients were randomly assigned into derivation cohort (801cases) and validation cohort (200 cases) in 8:2 ratio, respectively, in which in derivation cohort we found that 7 predictors, including LDH >350U/L, HR>130 times/min, room air PaO₂ <70mmHg, later admission to ICU, Anemia (HGB≤90g/L), CD4<50cells/ul, and development of a pneumothorax, were associated with poor prognosis in HIV/AIDS patients with PCP and were included in the predictive model. The model had excellent discrimination with AUC of 0.904 and 0.921 in derivation and validation cohort, respectively. The predicted scores were divided into two groups to assess the in-hospital mortality risk: low-risk group (0-11 points with mortality with 2.15-12.77%) and high-risk group (12-21 points with mortality with 38.78%-81.63%). The cumulative mortality rate also indicated significant difference between two groups with Kaplan-Meier curve (p<0.001). A predictive model to evaluate mortality in HIV/AIDS patients with PCP was constructed based on routine laboratory and clinical parameters, which may be a simple tool for physicians to assess the prognosis in HIV/AIDS patients with PCP in China.

A Low Frequency of IL-17-Producing CD8+ T-Cells Is Associated With Persistent Immune Activation in People Living With HIV Despite HAART-Induced Viral Suppression

Immune activation is the hallmark of HIV infection, even in patients with highly active anti-retroviral therapy (HAART)-induced viral suppression. A major cause of immune activation during HIV infection is the intestinal microbial translocation as a consequence, among other factors, of the decrease and/or dysfunction of interleukin (IL)-17-producing T-cells, due to their role promoting the integrity of the intestinal barrier. A population of IL-17-producing CD8⁺ T-cells (Tc17 cells), characterized by the expression of CD161, has been described, but its relation with the persistent immune activation in non-viremic people living with HIV (PLWH) on HAART is unclear. By flow cytometry, we characterized the activation phenotype (evaluated by the expression of HLA-DR and CD38) of circulating CD161-expressing CD8⁺ T-cells; in addition, we explored the functionality of polyclonally-stimulated Tc17 cells in PLWH under HAART-induced viral suppression, and in healthy individuals. Finally, we determined the association of Tc17 cells with the expression of cellular and soluble activation markers. Circulating CD161-expressing CD8⁺ T-cells were decreased in PLWH compared with healthy individuals, despite their similar basal activation state. After polyclonal stimulation, IL-17 production was higher in CD8⁺ T-cells co-expressing HLA-DR and CD38 in healthy individuals. In contrast, although PLWH had a higher frequency of HLA-DR⁺ CD38⁺ CD8⁺ T-cells after stimulation, they had a lower production of IL-17. Interferon (IFN)-γ-producing CD8⁺ T-cells (Tc1 cells) were increased in PLWH. The low Tc17 cells response was associated with a high expression of CD38 and programmed death 1 protein, high levels of soluble CD14 and the treatment duration. Finally, to explore potential immunomodulatory strategies, the in vitro effect of the anti-inflammatory agent sulfasalazine was assessed on Tc17 cells. Interestingly, a decreased inflammatory environment, death of activated CD8⁺ T-cells, and an increased frequency of Tc17 cells were observed with sulfasalazine treatment. Thus, our findings suggest that activated CD8⁺ T-cells have a marked capacity to produce IL-17 in healthy individuals, but not in PLWH, despite HAART. This dysfunction of Tc17 cells is associated with the persistent immune activation observed in these patients, and can be partially restored by anti-inflammatory agents.

Full blood count values as a predictor of poor outcome of pneumonia among HIV-infected patients

BACKGROUND

To evaluate the predictive value of analytical markers of full blood count that can be assessed in the emergency department for HIV infected patients, with community-acquired pneumonia (CAP).

METHODS

Prospective 3-year study including all HIV-infected patients that went to our emergency department with respiratory clinical infection, more than 24-h earlier they were diagnosed with CAP and required admission. We assessed the different values of the first blood count performed on the patient as follows; total white blood cells (WBC), neutrophils, lymphocytes (LYM), basophils, eosinophils (EOS), red blood cells (RBC), hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, red blood cell distribution width (RDW), platelets (PLT), mean platelet volume, and platelet distribution width (PDW). The primary outcome measure was 30-day mortality and the secondary, admission to an intensive care unit (ICU). The predictive power of the variables was determined by statistical calculation.

RESULTS

One hundred sixty HIV-infected patients with pneumonia were identified. The mean age was 42 (11) years, 99 (62%) were male, 79 (49%) had ART. The main route of HIV transmission was through parenteral administration of drugs. Streptococcus pneumonia was the most frequently identified etiologic agent of CAP The univariate analysis showed that the values of PLT (p < 0.009), EOS (p < 0.033), RDW (p < 0.033) and PDW (p < 0.09) were predictor of mortality, but after the logistic regression analysis, no variable was shown as an independent predictor of mortality. On the other hand, higher RDW (OR = 1.2, 95% CI 1.1-1.4, p = 0.013) and a lower number of LYM (OR 2.2, 95% CI 1.1-2.2; p = 0.035) were revealed as independent predictors of admission to ICU.

CONCLUSION

Red blood cell distribution and lymphocytes were the most useful predictors of disease severity identifying HIV infected patients with CAP who required ICU admission.

Country of residence is associated with distinct inflammatory biomarker signatures in HIV-infected patients

BACKGROUND

Inflammation and coagulation biomarkers are independent predictors of morbidity and mortality in HIV-infected patients. The impact of country of residence on these biomarkers is unknown and was investigated in persons at similar stages of HIV infection.

METHODS

Cryopreserved plasma specimens were analysed from 267 ART-naive patients with CD4 cell counts <100 cells/μl from Mexico (n=124) and South Africa (n=143). Biomarkers were compared and dimension reduction analyses were performed to highlight biosignatures according to nationality, gender and tuberculosis co-infection.

RESULTS

Mexican patients were significantly different from South Africans with regard to age, gender, CD4 cell count, haemoglobin, presence of AIDS-defining illness and prevalence of active tuberculosis. After adjusting for baseline characteristics, patients from Mexico had higher levels of IFN-γ, IL-8, and CXCL-10 whereas patients from South Africa had higher levels of fibrinogen, LTB4, P-selectin, protein S, and sCD40 ligand. The effect of country on the profile of biomarker expression was stronger than gender differences and tuberculosis co-infection.

CONCLUSION

Inflammation and coagulation biomarkers vary significantly by country. Further studies are needed to evaluate how these differences may contribute to HIV pathogenesis and prognosis in diverse populations and how they can be accounted for in studies using biomarkers as surrogate end points.

Immune activation during acute HIV infection and the impact of early antiretroviral therapy

PURPOSE OF REVIEW

The purpose of this review is to outline recent data pertaining to mechanisms of immune activation in acute infection and describe new developments that seek to determine if early antiretroviral treatment can mitigate chronic immune activation.

RECENT FINDINGS

Following the detection of HIV RNA, highly activated CD8 T cells expand and peak approximately 2 weeks following peak viral load whereas levels of proinflammatory soluble markers coincide with a rise in viral load. Immune activation during acute infection is driven by many factors including pyroptosis, replicative capacity of the infecting virus, and loss of Th17 cells within the gut. Early antiretroviral therapy (ART), particularly if initiated in Fiebig I (HIV IgM-), preserved mucosal CD4 T cells, possibly preventing the release of microbial products associated with immune activation. Viral reservoirs were restricted by the early initiation of ART, and heightened systemic immune activation was partially prevented compared with chronic HIV infection. A strong correlation was found between the size of the viral reservoir and cellular immune activation.

SUMMARY

The timing of immune activation during acute infection occurs shortly after exposure. Recent studies demonstrated that ART mitigates inflammatory responses, preserves CD4 T cells, and limits reservoir seeding if provided early in acute HIV infection.

Unique cytokine and chemokine patterns in bronchoalveolar lavage are associated with specific causative pathogen among HIV infected patients with pneumonia, in Medellin, Colombia

We wanted to investigate the pro-inflammatory cytokine/chemokine profile associated with the etiological agents identified in HIV patients. Immunosuppressed patients admitted to two hospitals in Medellin, Colombia, with clinical and radiographic diagnosis of pneumonia were enrolled in the study. After consent, bronchoalveolar lavage (BAL) was collected for bacterial, mycobacterial and fungal diagnosis. All patients were followed for a year. A stored BAL sample was used for cytokine/chemokine detection and measurement using commercial, magnetic human cytokine bead-based 19-plex assays. Statistical analysis was performed by assigning cytokine/chemokine concentrations levels into <25 percentile (lower), 25-75 percentile (normal) and >75 percentile (higher). Principal component analysis (PCA) and Kruskal-Wallis analysis were conducted to identify the clustering of cytokines with the various infectious etiologies (fungi, Mycobacterium tuberculosis - MTB, and bacteria). Average age of patients was 35, of whom 77% were male, and the median CD4 count of 33cells/μl. Of the 57 HIV infected patients, in-hospital mortality was 12.3% and 33% died within a year of follow up. The PCA revealed increased IL-10, IL-12, IL-13, IL-17, Eotaxin, GCSF, MIP-1α, and MIP-1β concentrations to be associated with MTB infection. In patients with proven fungal infection, low concentrations of IL-1RA, IL-8, TNF-α and VEGF were identified. Bacterial infections displayed a distinct cytokine pattern and were not misclassified using the MTB or fungi cytokine patterns (p-value<0.0001). Our results indicate a unique pattern of pro-inflammatory cytokine/chemokine, allowing differentiation between bacterial and non-bacterial pathogens. Moreover, we found distinct, if imperfectly discriminatory, cytokine/chemokine patterns associated with MTB and fungal infections.