Diagnostic performance of CL Detect rapid-immunochromatographic test for cutaneous leishmaniasis: a systematic review and meta-analysis.

BACKGROUND: Sensitive, robust, and fast point-of-care tests are needed for cutaneous leishmaniasis (CL) diagnosis. The recently developed CL Detect rapid test (InBios) for detecting Leishmania peroxidoxin antigen has been evaluated in several studies. However, diagnostic performances were controversial. Therefore, this systematic review and meta-analysis aimed to determine the pooled sensitivity and specificity of CL Detect for CL diagnosis. METHODS: PubMed, Scopus, EMBASE, ScienceDirect, and Google Scholar were sources of articles. We included studies reporting the diagnostic accuracy of CL Detect and CL-suspected patients in the English language. The methodological qualities of the included studies were appraised using the quality assessment of diagnostic accuracy studies-2 (QUADAS-2). Meta-analysis was conducted using Stata 14.2 and R software. RESULTS: A total of 9 articles were included. The study sample size ranged from 11 to 274. The sensitivities of the individual studies ranged from 23 to 100%, and the specificities ranged from 78 to 100%. Pooled sensitivity and specificity were 68% (95% CI, 41-86%) and 94% (95% CI, 87-97%), respectively. AUC displayed 0.899. Pooled sensitivity was lower (47%, 95% CI, 34-61%) when PCR was used as a reference than microscopy (83%, 95% CI, 39-97%). Pooled sensitivity was lower (48%, 95% CI, 30-67%) for all lesion durations compared to ≤ 4 months (89%, 95% CI, 43-99%). CONCLUSIONS: CL Detect has poor sensitivity and does not meet the minimal sensitivity of 95% of target product profiles designed for CL point-of-care tests. Currently, the CL Detect test looks unsuitable for CL diagnosis, despite its high specificity. Findings are limited by the low number of studies available. Further large-scale studies are recommended. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022323497.

Helminth species-specific effects on IFN-γ producing T cells during active and latent tuberculosis.

BACKGROUND: Interferon-γ (IFN-γ) is a key cytokine inducing protective immune responses during tuberculosis (TB) infection. Helminth-induced immune responses may affect IFN-γ production by T cells, although its connection with disease severity and immune recovery during treatment is unexplored. We investigated the species-specific effect of helminths on the IFN-γ production by T cells in relation to disease severity during active and latent TB infection (LTBI). METHODS: In this study, 69 active pulmonary TB patients (PTB), 28 with LTBI and 66 healthy controls were included. Active TB was diagnosed using GenXpert MTB/RIF while QuantiFERON test (QFT) was used for the screening of healthy community controls (CCs) and for the diagnosis of LTBI. Helminth infection was identified by routine diagnosis whereas clinical disease severity was evaluated by the TB score. Intracellular IFN-γ production of T cells in stimulated peripheral blood mononuclear cells (PBMCs) was analyzed by flow cytometry using TB antigens (PPD), the polyclonal T cell activator staphylococcal enterotoxin B (SEB), or medium as unstimulated control. RESULTS: Helminth infected CCs and LTBI subjects showed a significant reduction of IFN-γ+ CD4+ T cells by PPD-stimulation compared to non-helminth infected control groups. The significant reduction in the frequency of IFN-γ+ T cells in both latent and active PTB patients following SEB stimulation was mostly attributed to Schistosoma mansoni infection, whereas Ascaris lumbricoides, Schistosoma mansoni, and hookworm infection contributed equally in CCs. Following anti-helminthic and anti-TB treatment for 2 months, the frequency of IFN-γ+ CD4 T cells in helminth coinfected PTB was restored to levels of helminth negative PTB before treatment. Helminth coinfected PTB patients with an intermediate and severe clinical course had reduced capacity for production of IFN-γ+ T cells compared to the corresponding non-helminth infected PTB. CONCLUSION: We found a reduction in IFN-γ producing T cells by helminth coinfection which was restored following anti-helminthic treatment. This reduction was helminth species-dependent in an exploratory sub-analysis and correlated to increased disease severity.

Association of Cytotoxic T-Lymphocyte Antigen-4 Gene Polymorphism with Type 1 Diabetes Mellitus: In silico Analysis of Biological Features of CTLA-4 Protein on Ethiopian Population.

Background: T1DM is a chronic organ-specific T-cell-mediated autoimmune disease characterized by the selective destruction of ß-cells in the islets of Langerhans, resulting in insulin deficiency and hyperglycemia. Genes for cytotoxic T lymphocyte-associated antigen 4 have been hypothesized as possible contender genes for T1DM vulnerability. However, it has not been studied in the Ethiopian population yet. Objective: The aim of the study was to investigate CTLA-4 exon 1 was linked to A49G polymorphism with T1DM and its biological features of CTLA-4 among T1DM patients, in Ethiopia. Methods: A case-control study was done from December 2019 to March 2020 on 210 study participants (105 T1DM patients and 105 healthy controls). Polymerase Chain Reaction amplification with forward and reverse primers was followed by restriction fragment length polymorphism and gel electrophoresis to determine gene polymorphism. Bioinformatics data of SNP was retrieved from National Centers for Biotechnology Information databases. The chi-square test and logistic regression were used. Statistical significance was defined as a P-value of less than 0.05. Results: The CTLA-4 (+A49G) gene polymorphism was observed on 56 (26.7%) study participants, 39 (18.57%) of T1DM patients, and 17 (0.08%) were controls. In T1DM and controls, the frequency of the A allele was 73.3% and 89.5%, while the G allele was 26.7% and 10.5%, respectively. The G allele was found to be associated with T1DM (OR=3.1; 95% CI, 1.82 -5.32; P=0.001). Statistical analysis revealed an association between the likelihood of T1DM and GG genotype of the CTLA-4 (+A49G) gene polymorphism (OR=3.11; 95% CI, 1.37-10.90; P=0.01). Further in silico analyzed the SNP to assess its biological features. Conclusion: The study showed as CTLA-4 (+A49G) gene polymorphism is linked with T1DM in the Ethiopian population.

Helminth species dependent effects on Th1 and Th17 cytokines in active tuberculosis patients and healthy community controls.

Despite that the impact of different helminth species is not well explored, the current dogma states that helminths affect the Th1/Th2 balance which in turn affects the risk of tuberculosis (TB) reactivation and severity of disease. We investigated the influence of helminth species on cytokine profiles including IL-17A in TB patients and healthy community controls (CCs). In total, 104 newly diagnosed pulmonary TB patients and 70 HIV negative and QuantiFERON negative CCs in Gondar, Ethiopia were included following helminth screening by stool microscopy. Plasma samples and ex vivo stimulation of peripheral blood mononuclear cells (PBMCs) with purified protein derivative (PPD) and Staphylococcus enterotoxin B (SEB) was used to determine cytokine profiles by cytometric bead array. In CCs, Ascaris lumbricoides or Schistosoma mansoni infections were associated with an impaired Th1-type response (IFN-gamma, IL-6 and TNF-alpha) in PBMCs mainly with SEB stimulations, whereas in TB patients only hookworm infection showed a similar pattern. Among CCs, the IL-17A response in PBMCs stimulated with SEB was higher only for S. mansoni, whereas in TB patients, the elevated systemic IL-17A plasma level was significantly suppressed in hookworm infected TB patients compared to patients without helminth coinfection. Following treatment of TB and helminth infection there was a general decrease in ex vivio IL-10 and TNF-alpha production in unstimulated, PPD or SEB stimulated PBMCs that was the most pronounced and significant in TB patients infected with S. mansoni, whereas the follow-up levels of IFN-gamma and IL-17A was significantly increased only in TB patients without helminth coinfection from PBMCs stimulated mainly with SEB. In summary, in addition to confirming helminth specific effects on the Th1/Th2 response before and after TB treatment, our novel finding is that IL-17A was impaired in helminth infected TB patients especially for hookworm, indicating a helminth species-specific immunoregulatory effect on IL-17A which needs to be further investigated.

Hematological profiles of visceral leishmaniasis patients before and after treatment of anti-leishmanial drugs at University of Gondar Hospital; Leishmania Research and Treatment Center Northwest, Ethiopia.

BACKGROUND: Visceral leshimaniasis is a parasitic disease characterized by systemic infection of phagocytic cells and an intense inflammatory response. The progression of the disease or treatment may have an effect on hematological parameters of these patients'. Thus, the current study sought to compare the hematological profiles of visceral leishmaniasis patients before and after treatment with anti-leishmaniasis drugs. METHOD: An institutional-based retrospective cohort study was conducted among visceral leishmaniasis patients admitted to the University of Gondar comprehensive specialized referral hospital leishmaniasis research and treatment centre between September 2013 and August 2018. Hematological profiles were extracted from the laboratory registration book before and after treatment. Data were entered to Epi-info and exported to SPSS for analysis. Descriptive statistics were summarized using frequency and percentage to present with the table. The mean, standard deviation, median, and interquartile range were used to present the data. Furthermore, using the paired t-test and the Wilcoxon Signed rank test, the mean difference for normally and non-normally distributed data was compared. Spearman and Pearson correlation analysis were used to describe the relationship between hematological parameters and various variables. A P value of 0.05 was considered statistically significant. RESULT: With the exception of the absolute neutrophil count, all post-treatment hematological parameters show a significant increase when compared to pre-treatment levels. Prior to treatment, the prevalence of anemia, leukopenia, and thrombocytopenia was 85.5, 83.4, and 75.8%, respectively, whereas it was 58.3, 38.2, and 19.2% following treatment. Furthermore, parasite load was found to have a statistically significant negative correlation with hematological profiles, specifically with white blood cell and red blood cell parameters. CONCLUSION: According to our findings, patients with visceral leishmaniasis had improved hematological profiles after treatment. The effect of treatment on parasite proliferation and concentration within visceral organs, in which the parasite load could directly affect the patient's hematological profiles, may be associated with the change in hematological profiles.

Opportunistic Cryptococcal Antigenemia in the HAART Era at HIV Epidemic Settings of Northwest Ethiopia.

BACKGROUND: Cryptococcus neoformans is a frequent opportunistic infection in patients with the acquired immunodeficiency syndrome. While the advent of ART reduces the occurrence of cryptococcal meningitis in HIV patients, cryptococcal disease remains a leading cause of morbidity and mortality in the developing world especially in sub-Saharan Africa which is the epicenter of HIV. This study aimed to assess the cryptococcal antigenemia, CD4+ Th cell counts, HIV RNA viral load, and clinical presentations among HIV-positive patients in Northwest Ethiopia. METHOD: A total of two hundred (200) HIV-positive patients were recruited for this study. Cryptococcus antigenemia prevalence in plasma samples of HIV-positive patients was determined by using Antigen lateral flow assay (CrAg-LFA) also, and CD4+ Th cell counts and HIV-RNA levels were quantified from blood specimen. Patients' demographic data, clinical manifestation, and concurrent opportunistic infection were recorded. RESULT: The sex distributions of study participants were 105(52.5%) male and 94(47.5%) female with an age range of 15-65 (mean 39.42 ± 9) years. All patients had a CD4+ T-cell count <100 cells/µl with the median 54 cells/µl and median HIV-RNA viral load 2.16 × 105 RNA copies/ml (50-3.66 × 105 RNA copies/ml); the prevalence of cryptococcal antigenemia was found to be 4% in HIV-positive patients. More than half and two third of CrAg-positive patients had a CD4 count <25 cells/µl and HIV viral load >10,000 copies/ml, respectively, as well; Tuberculosis, Candidiasis, and herpes zoster are the most often observed concurrent infections while cryptococcal antigenemia is significantly associated with oral candidiasis (p < 0.001). CONCLUSION: Although the advent of ART, early diagnosis of cryptococcosis, and application of antifungal interventions, HIV-induced cryptococcal antigenemia positivity in HIV infected individuals is still the countries' big challenge. Thus, stringent follow-up and case management should be considered.

Whole Blood Stimulation Assay as a Treatment Outcome Monitoring Tool for VL Patients in Ethiopia: A Pilot Evaluation.

Visceral leishmaniasis (VL) is a lethal disease if left untreated. Current treatments produce variable rates of treatment failure and toxicity without sterile cure, rendering treatment efficacy monitoring essential. To avoid repeated invasive tissue aspirates as well as empirical treatment, there is a need for new tools that allow a less-invasive and early assessment of treatment efficacy in the field. Cross-sectional studies have suggested levels of cytokines/chemokines after whole blood stimulation as good markers of cure, but longitudinal studies are lacking. In this study, we followed 13 active VL cases in an endemic area in Ethiopia by measuring the production of IFN-γ, TNF-α, IP-10, IL-2, IL-10, MCP-1, and MIG before, during, and at the end of treatment. After 24 hours of stimulation of whole blood with soluble Leishmania antigen, we observed an early, robust, and incremental increase of IFN-γ, TNF-α, and IP-10 levels in all patients during treatment. Moreover, based on the IFN-γ levels that showed an average 13-fold increase from the time of diagnosis until the end of treatment, we could almost perfectly discriminate active from cured status. Similar concentrations and patterns were found in stimulation assays with the two main Leishmania species. The levels of IFN-γ, IP-10, or TNF-α also seemed to be inversely associated with the parasite load at baseline. Despite a 1/10 drop in concentrations, similar patterns were observed in IFN-γ and IP-10 levels when dried plasma spots were stored at 4°C for an average of 225 days. All the above evidence suggests a detectable restoration of cell-mediated immunity in VL and its association with parasite clearance. With a potential application in rural settings by means of dried plasma spots, we recommend to further explore the early diagnostic value of such assays for treatment efficacy monitoring in large cohort studies including treatment failure cases.

Seroprevalence of HIV among pregnant women in Ethiopia: a systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis aimed to determine the pooled prevalence of HIV among pregnant women in Ethiopia. RESULT: PubMed, EMBASE, Science Direct and Google scholar databases were searched to retrieve 15 relevant articles based on the inclusion criteria. A total of 13,746 participants were included in the original studies and considered in this analysis. Among subjects, 717 were infected with HIV only, and 12 were HIV-HBV co-infected pregnant women. In this meta-analysis, the pooled prevalence of HIV among pregnant women in Ethiopia was 5.74% (95% CI 3.96-7.53%). Regional analysis showed that 9.50% (95% CI 7.76-11.23%) in Amhara, 4.80% (95% CI 3.12-6.49%) in Addis Ababa, 2.14% (95% CI - 0.54 to 4.82%) in SNNP and 4.48% (95% CI 2.56-6.41%) in Oromia region. Besides, six studies reported HIV-HBV co-infection and the pooled prevalence was 0.68% (95% CI 0.27-1.08%) among pregnant women in Ethiopia.

Disease severity in patients with visceral leishmaniasis is not altered by co-infection with intestinal parasites.

Visceral leishmaniasis (VL) is a neglected tropical disease that affects the poorest communities and can cause substantial morbidity and mortality. Visceral leishmaniasis is characterized by the presence of Leishmania parasites in the spleen, liver and bone marrow, hepatosplenomegaly, pancytopenia, prolonged fever, systemic inflammation and low body mass index (BMI). The factors impacting on the severity of VL are poorly characterized. Here we performed a cross-sectional study to assess whether co-infection of VL patients with intestinal parasites influences disease severity, assessed with clinical and haematological data, inflammation, cytokine profiles and BMI. Data from VL patients was similar to VL patients co-infected with intestinal parasites, suggesting that co-infection of VL patients with intestinal parasites does not alter disease severity.

Visceral Leishmaniasis Patients Display Altered Composition and Maturity of Neutrophils as well as Impaired Neutrophil Effector Functions.

Immunologically, active visceral leishmaniasis (VL) is characterized by profound immunosuppression, severe systemic inflammatory responses, and an impaired capacity to control parasite replication. Neutrophils are highly versatile cells, which play a crucial role in the induction as well as the resolution of inflammation, the control of pathogen replication, and the regulation of immune responses. Neutrophil functions have been investigated in human cutaneous leishmaniasis; however, their role in human VL is poorly understood. In the present study we evaluated the activation status and effector functions of neutrophils in patients with active VL and after successful anti-leishmanial treatment. Our results show that neutrophils are highly activated and have degranulated; high levels of arginase, myeloperoxidase, and elastase, all contained in neutrophils' granules, were found in the plasma of VL patients. In addition, we show that a large proportion of these cells are immature. We also analyzed effector functions of neutrophils that are essential for pathogen clearance and show that neutrophils have an impaired capacity to release neutrophil extracellular traps, produce reactive oxygen species, and phagocytose bacterial particles, but not Leishmania parasites. Our results suggest that impaired effector functions, increased activation, and immaturity of neutrophils play a key role in the pathogenesis of VL.