Bacterial sepsis in patients with visceral leishmaniasis in Northwest Ethiopia

Hematological and Clinical Features Associated with Initial Poor Treatment Outcomes in Visceral Leishmaniasis Patients with and without HIV Coinfection in Gondar, Northwest Ethiopia

Ethiopia is among the countries with a high leishmaniasis burden. In this retrospective review, we aimed to determine hematological and clinical features associated with initial poor treatment outcomes of visceral leishmaniasis (VL) patients. The majority of VL cases in this study had leucopenia (94.3%), thrombocytopenia (87.1%), and anemia (85.9%). HIV coinfection was present in 7.0% (n = 23) of VL cases. At the center, VL patients without HIV coinfection were treated with sodium stibogluconate and paromomycin combination, whereas HIV coinfected cases were treated with AmBisome and miltefosine combination therapy. End-of-treatment cure rates among HIV-positive and HIV-negative visceral leishmaniasis cases, respectively, were 52.2% and 96.9%. Case fatality rates were 34.8% and 2.7% in HIV-positive and HIV-negative cases, respectively. Overall, non-survivors in this study were more likely to have HIV (55.0% vs. 4.1%, p < 0.001), sepsis (15.0% vs. 1.4%, p = 0.019), and dyspnea (40.0% vs. 2.7%, p < 0.001) at admission. In this regard, particular attention to the management of superimposed disease conditions at admission, including sepsis, HIV, and dyspnea, is needed to improve VL patients’ treatment outcomes. The inadequacy of the current treatments, i.e., AmBisome and miltefosine combination therapy, for HIV coinfected visceral leishmaniasis patients requires further attention as it calls for new treatment modalities.

[Pancytopenia and B-symptoms - an unexpected souvenir?]

HISTORY

 The 79-year-old patient was admitted with recurring fever, weight loss, night sweat, a decrease in physical capacity and hematomas of the extremities.

FINDINGS

 The patient presented with pancytopenia, elevated CRP and impaired renal function. A splenomegaly was evident in abdominal sonography. A bone marrow aspiration was performed.

DIAGNOSIS

 Histopathologic examination revealed a visceral Leishmaniasis. The diagnosis was confirmed by PCR from peripheral blood.

THERAPY AND COURSE

 After initiation of liposomal amphotericin B haematopoiesis recovered and CRP decreased. Initially the renal function deteriorated with prolongated improvement in the course of therapy.

CONCLUSIONS

 Pancytopenia and corresponding symptoms are suspect for visceral Leishmaniasis also in patients supposed to be immunocompetent with travel history of endemic regions.

Leishmania and its relationships with bacteria

Leishmaniasis is a zoonotic and neglected disease, which represents an important public health problem worldwide. Different species of Leishmania are associated with different manifestations, and a practical problem that can worsen the condition of hosts infected with Leishmania is the secondary infection caused by bacteria. This review aims to examine the importance and prevalence of bacteria co-infection during leishmaniasis and the nature of this ecological relationship. In the cases discussed in this review, the facilitation phenomenon, defined as any interaction where the action of one organism has a beneficial effect on an organism of another species, was considered in the Leishmania-bacteria interaction, as well as the effects on one another and their consequences for the host.

Estimates of gene ensemble noise highlight critical pathways and predict disease severity in H1N1, COVID-19 and mortality in sepsis patients

Finding novel biomarkers for human pathologies and predicting clinical outcomes for patients is challenging. This stems from the heterogeneous response of individuals to disease and is reflected in the inter-individual variability of gene expression responses that obscures differential gene expression analysis. Here, we developed an alternative approach that could be applied to dissect the disease-associated molecular changes. We define gene ensemble noise as a measure that represents a variance for a collection of genes encoding for either members of known biological pathways or subunits of annotated protein complexes and calculated within an individual. The gene ensemble noise allows for the holistic identification and interpretation of gene expression disbalance on the level of gene networks and systems. By comparing gene expression data from COVID-19, H1N1, and sepsis patients we identified common disturbances in a number of pathways and protein complexes relevant to the sepsis pathology. Among others, these include the mitochondrial respiratory chain complex I and peroxisomes. This suggests a Warburg effect and oxidative stress as common hallmarks of the immune host-pathogen response. Finally, we showed that gene ensemble noise could successfully be applied for the prediction of clinical outcome namely, the mortality of patients. Thus, we conclude that gene ensemble noise represents a promising approach for the investigation of molecular mechanisms of pathology through a prism of alterations in the coherent expression of gene circuits.

Bacterial Profile among Patients with Suspected Bloodstream Infections in Ethiopia: A Systematic Review and Meta-Analysis

INTRODUCTION

The burden of bloodstream infections (BSIs) has been warranted in Ethiopia. Globally, the emergency and raised resistance rate of bacterial antimicrobial resistance is becoming a prominent problem, and it is difficult to treat patients having sepsis. In this review, we aimed to determine the pooled prevalence of bacterial isolates among presumptive patients with bloodstream infections in Ethiopia.

METHODS

A systematic search was performed from PubMed/MEDLINE, Scopus, HINARI, ScienceDirect, and Google Scholar electronic databases using PRISMA guidelines. The data analysis was carried out using STATATM version 14 after the records were cleaned and sorted out.

RESULTS

A total of 26 studies with 8,958 blood specimens and 2,382 culture-positive bacterial isolates were included for systematic review and meta-analysis. The meta-analysis derived a pooled culture-positive bacterial prevalence which was 25.78% (95% CI: 21.55-30.01%). The estimated pooled prevalence of Gram-positive and Gram-negative bacterial isolates was 15.50% (95% CI: 12.84-18.15%) and 10.48 % (95% CI: 8.32-12.63%), respectively. The two common Gram-positive bacteria isolated from patients suspected of BSIs were coagulase-negative Staphylococcus with a pooled prevalence of 5.75% (95% CI: 4.58-6.92%) and S. aureus 7.04 % (95% CI: 5.37-8.72%). Similarly, the common Gram-negative bacterial isolates and their estimated pooled prevalence were E. coli 1.69% (95% CI: 1.21-2.16%), Klebsiella species 7.04 % (95% CI: 5.37-8.72%), Pseudomonas species 0.39% (95% CI: 0.08-0.70%), Salmonella species 1.09% (95% CI: 0.79-1.38%), and Streptococcus pyogenes 0.88% (95% CI: 0.54-1.22%).

CONCLUSION

The prevalence of bacterial isolates among presumptive patients suspected to BSIs in Ethiopia remains high. Furthermore, we found a remarkable variation in the pathogen distribution across the study setting.

Prognostic factors for mortality among patients with visceral leishmaniasis in East Africa: Systematic review and meta-analysis

BACKGROUND

Visceral leishmaniasis (VL) is a vector-borne disease that is deadly if left untreated. Understanding which factors have prognostic value may help to focus clinical management and reduce case fatality. However, information about prognostic factors is scattered and conflicting. We conducted a systematic review and meta-analysis to identify prognostic factors for mortality among VL patients in East Africa.

METHODOLOGY/PRINCIPAL FINDINGS

The review protocol was registered in PROSPERO (CRD42016043112). We included studies published in English after 1970 describing VL patients treated in East African health facilities. To be included, studies had to report on associations between clinical or laboratory factors and mortality during admission or during VL treatment, with a minimal study size of ten patients. Conference abstracts and evaluations of genetic or immunological prognostic factors were excluded. We searched for studies in MEDLINE and four other databases in December 2018. To assess the risk of bias in observational studies and clinical trials, we used the Quality in Prognostic Studies (QUIPS) tool. We included 48 studies in the systematic review, describing 150,072 VL patients of whom 7,847 (5.2%) died. Twelve prognostic factors were evaluated in five or more studies and these results were submitted to meta-analysis producing one pooled crude odds ratio (OR) per prognostic factor. The following factors were strongly (OR>3) and significantly (P-value<0.05) associated with mortality: jaundice (OR = 8.27), HIV (OR = 4.60), tuberculosis (OR = 4.06), age >45 years (OR = 3.69), oedema (OR = 3.52), bleeding (OR = 3.37), and haemoglobin ≤6.5 g/dl (OR = 3.26). Factors significantly and moderately (OR between one and three) associated with death were severe malnutrition, long duration of illness, young age (<5 years), and large spleen size.

CONCLUSIONS/SIGNIFICANCE

These prognostic factors can be identified by health professionals in resource-constrained settings. They should be considered as "core" prognostic factors in future studies that aim at improving the prognosis of VL patients.

Fatal progression of experimental visceral leishmaniasis is associated with intestinal parasitism and secondary infection by commensal bacteria, and is delayed by antibiotic prophylaxis

Leishmania donovani causes visceral leishmaniasis (VL), which is typically fatal without treatment. There is substantial variation between individuals in rates of disease progression, response to treatment and incidence of post-treatment sequelae, specifically post-kala-azar dermal leishmaniasis (PKDL). Nevertheless, the majority of infected people are asymptomatic carriers. Hamsters and mice are commonly used as models of fatal and non-fatal VL, respectively. Host and parasite genetics are likely to be important factors, but in general the reasons for heterogeneous disease presentation in humans and animal models are poorly understood. Host microbiota has become established as a factor in cutaneous forms of leishmaniasis but this has not been studied in VL. We induced intestinal dysbiosis in mice and hamsters by long-term treatment with broad-spectrum antibiotics in their drinking water. There were no significant differences in disease presentation in dysbiotic mice. In contrast, dysbiotic hamsters infected with L. donovani had delayed onset and progression of weight loss. Half of control hamsters had a rapid progression phenotype compared with none of the ABX-treated animals and the nine-month survival rate was significantly improved compared to untreated controls (40% vs. 10%). Antibiotic-treated hamsters also had significantly less severe hepatosplenomegaly, which was accompanied by a distinct cytokine gene expression profile. The protective effect was not explained by differences in parasite loads or haematological profiles. We further found evidence that the gut-liver axis is a key aspect of fatal VL progression in hamsters, including intestinal parasitism, bacterial translocation to the liver, malakoplakia and iron sequestration, none of which occurred in non-progressing murine VL. Diverse bacterial genera were cultured from VL affected livers, of which Rodentibacter was specifically absent from ABX-treated hamsters, indicating this pathobiont may play a role in promoting disease progression. The results provide experimental support for antibiotic prophylaxis against secondary bacterial infections as an adjunct therapy in human VL patients.

Prevalence estimates of human immunodeficiency virus (HIV) infection among visceral leishmaniasis infected people in Northwest Ethiopia: a systematic review and meta-analysis

Background

In Ethiopia, by the end of 2018, an estimated 690,000 people are infected with HIV and the annual cases of Visceral Leishmaniasis (VL) is estimated to be between 4000 and 5000 with over 3.2 million people are at risk. Northwest Ethiopia accounts for over 60% cases of VL in the country. Prevalence of HIV infection among VL infected people in Ethiopia has not yet been synthesized. Therefore, we aimed to estimate the pooled prevalence of HIV infection among VL infected people in Northwest Ethiopia with the hope that it would guide the development of a more robust and cost-effective intervention strategies.

Methods

In this systematic review and meta-analysis, we searched six international databases: PubMed, Ovid MEDLINE®, Embase, Scopus, Google Scholar, and ProQuest Dissertations & Theses. We also searched reference lists of included studies and Ethiopian universities electronic thesis and dissertation repositories. The search was performed until June 30,2019. Funnel plot symmetry visualization confirmed by Egger’s regression asymmetry test and Begg rank correlation methods was used to assess publication bias. Pooled prevalence estimate was calculated using Der Simonian and Laird’s random Effects model. We went further to perform univariate meta-regression and subgroup analysis to identify a possible sources of heterogeneity among the studies. STATA software (version 14, Texas, USA) was used for analysis.

Results

From 1286 citations identified by our search, 19 relevant studies with 5355 VL infected individuals were included in this meta-analysis. The pooled prevalence of HIV infection among VL infected individuals in Northwest Ethiopia was 24% (95%CI: 17–30%). The result of sensitivity analysis demonstrated that the pooled prevalence estimate was robust and not one-study dependent. The pooled prevalence estimate of HIV infection among VL infected people in Northwest Ethiopia ranged from 20.88% (95%CI: 15.91–25.86) to 24.86% (95%CI: 18.57–31.14) after a single study was deleted.

Conclusions

The burden of HIV infection in people infected with VL in Northwest Ethiopia is considerably high. Integrating HIV/AIDS surveillance among VL infected people would improve case detection as well as prevention and control of disease spread.

Disorganization of spleen compartments and dermatitis in canine visceral leishmaniasis

Canine visceral leishmaniasis is associated with splenic changes that may interfere with the surveillance of blood borne antigens. Dogs with terminal visceral leishmaniasis present with a variety of skin lesions that may reflect a failure of the immune system to cope with infection. In this study, we compare the frequency of dermatitis in dogs from an endemic area of visceral leishmaniasis and take account of the following parameters: presence/absence of laboratory markers of infection and susceptibility to visceral leishmaniasis, and presence/absence of splenic structural changes associated with severe forms of the disease. Dermatitis was present in 48 of 64 (75%) of the animals. Dermatitis was more frequent in animals with positive splenic culture and negative leishmanin skin test (14/15, 93%) than in non-infected controls (P = 0.01). Diffuse dermatitis was present only in animals with evidence of Leishmania infection. Diffuse dermatitis was also more frequent in animals with positive (9/27, 33%) as opposed to negative (3/34, 9%) serology against Leishmania (P = 0.01). Presence of dermatitis correlated with both perisplenitis (P = 0.03) and with an increase in plasma cell density in the splenic tissue (P = 0.02). Diffuse dermatitis also correlated with splenic lymphoid tissue disorganization (P = 0.03) and germinal center atrophy (P < 0.01). The relationship between chronic dermatitis and spleen disorganization suggests an impairment of immune response to deal with skin aggressions in dogs with severe forms of visceral leishmaniasis. It also suggest that skin biopsy can be used in a model to define severity of canine visceral leishmaniasis.

Prevalence and antimicrobial resistance of coagulase negative staphylococci clinical isolates from Ethiopia: a meta-analysis

Background

Antimicrobial resistant Coagulase-negative Staphylococci (CoNS) have limited treatment options, rendered diseases untreatable and made hospitals to be reservoirs of the resistant strains. The aim of this study was to estimate the pooled prevalence and antimicrobial resistance of clinical isolates of CoNS from Ethiopia.

Results

The electronic database search yielded 6511 articles of which 21 met predefined inclusion criteria. The pooled prevalence of CoNS from Ethiopia was 12% (95% confidence interval (CI): 8, 16%). The analyses revealed high level of CoNS resistance to methicilin (37%[95% CI: 21, 55%]), vancomycin (911%[95% CI: 0, 35%]), penicillin (58%[95% CI: 42, 74%]), amoxicillin (42%[95% CI: 23, 61%]), amoxicillin-clavulanate (27%[95% CI: 2, 27%]), ampicillin (64%[95% CI: 46, 80%]), tetracycline (60% [95% CI: 49, 70%]), doxycycline (36%[95% CI:19,55%]), Sulfamethoxazole-trimethoprim (50%[95% CI: 36, 64%]), ceftriaxone (27% [95% CI: 18, 38%]), cephalothin (32% [95% CI: 7, 62%]), norfloxacin (39%[95% CI: 24, 56%]), chloramphenicol (40%[95% CI: 23, 58%]), clindamycin (11% [95% CI: 2, 27%]), ciprofloxacin (14%[95% CI: 6, 22%]), gentamicin (27%[95% CI:19,36%]) and erythromycin (30%[95% CI:20%,42%]). High heterogeneity, I² ranging from 69.04 to 96.88%; p-values ≤0.01, was observed. Eggers’ test did not detect publication bias for the meta-analyses and low risk of bias was observed in included studies.

Conclusions

CoNS has gotten resistant to commonly used antimicrobials from Ethiopia. There is a need of launching national antimicrobial treatment, development and implementation of policy guidelines to contain the threat. Further research focusing on factors promoting resistance and the effect of resistance on treatment outcome studies are warranted.

Electronic supplementary material

The online version of this article (10.1186/s12866-018-1188-6) contains supplementary material, which is available to authorized users.

The initial effectiveness of liposomal amphotericin B (AmBisome) and miltefosine combination for treatment of visceral leishmaniasis in HIV co-infected patients in Ethiopia: A retrospective cohort study

BACKGROUND

North-west Ethiopia faces the highest burden world-wide of visceral leishmaniasis (VL) and HIV co-infection. VL-HIV co-infected patients have higher (initial) parasitological failure and relapse rates than HIV-negative VL patients. Whereas secondary prophylaxis reduces the relapse rate, parasitological failure rates remain high with the available antileishmanial drugs, especially when administered as monotherapy. We aimed to determine the initial effectiveness (parasitologically-confirmed cure) of a combination of liposomal amphotericin B (AmBisome) and miltefosine for treatment of VL in HIV co-infected patients.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a retrospective cohort study at a Médecins Sans Frontières-supported health center in north-west Ethiopia. We included VL-HIV co-infected adults, treated for VL between January 2011 and August 2014, with AmBisome infusion (30 mg/kg total dose) and miltefosine orally for 28 days (100 mg/day). Proportions of initial treatment outcome categories were calculated. Predictors of initial parasitological failure and of death were determined using multivariable logistic regression. Of the 173 patients included, 170 (98.3%) were male and the median age was 32 years. The proportion of patients with primary VL (48.0%) and relapse VL (52.0%) were similar. The majority had advanced HIV disease (n = 111; 73.5%) and were on antiretroviral therapy prior to VL diagnosis (n = 106; 64.2%). Initial cure rate was 83.8% (95% confidence interval [CI], 77.6-88.6); death rate 12.7% (95% CI, 8.5-18.5) and parasitological failure rate 3.5% (95% CI, 1.6-7.4). Tuberculosis co-infection at VL diagnosis was predictive of parasitological failure (adjusted odds ratio (aOR), 8.14; p = 0.02). Predictors of death were age >40 years (aOR, 5.10; p = 0.009), hemoglobin ≤6.5 g/dL (aOR, 5.20; p = 0.002) and primary VL (aOR, 8.33; p = 0.001).

CONCLUSIONS/SIGNIFICANCE

Initial parasitological failure rates were very low with AmBisome and miltefosine combination therapy. This regimen seems a suitable treatment option. Knowledge of predictors of poor outcome may facilitate better management. These findings remain to be confirmed in clinical trials.

Tuberculosis in Visceral Leishmaniasis-Human Immunodeficiency Virus Coinfection: An Evidence Gap in Improving Patient Outcomes?

Background

Visceral leishmaniasis (VL)-human immunodeficiency virus (HIV) coinfection remains a major problem in Ethiopia, India, and Brazil. Tuberculosis (TB), a treatable factor, could contribute to high mortality (up to 25%) in VL-HIV coinfection. However, the current evidence on the prevalence and clinical impact of TB in VL-HIV coinfection is very limited. In previous reports on routine care, TB prevalence ranged from 5.7% to 29.7%, but information on how and when TB was diagnosed was lacking.

Methods

Field observations suggest that TB work-up is often not done systematically, and it is only done in patients who do not respond well to VL treatment. Here, we advocate high-quality diagnostic studies in VL-HIV-coinfected patients, during which all patients are systematically screened for TB, including a comprehensive work-up, to obtain reliable estimates.

Results

Cost-effective and feasible diagnostic algorithms can be developed for field use, and this can be integrated in VL clinical guidelines.

Conclusions

An accurate diagnosis of TB can allow clinicians to assess its clinical impact and evaluate the impact of early TB diagnosis.

Antimicrobial Resistance of Sterile Site Infections in Sub-Saharan Africa: A Systematic Review

Sparse data exist from sub-Saharan Africa (SSA) on the prevalence of antimicrobial resistance (AMR). A prior review of antimicrobial resistance in SSA from 1990 to 2013 showed a high prevalence of AMR to commonly used antibiotics in this setting. We reviewed the literature published since 2013. Four databases (PubMed, EMBASE, Cochrane, and African Journals Online) were searched for articles between February 2013 and March 2016 with a focus on sterile site infections (bacteremia, urinary tract infections [UTIs], and meningitis). We focused on the original World Health Organization–identified priority pathogens and antibiotics, prior to the release of the most recently updated and expanded list in 2017. There were 19 eligible studies: bacteremia (12), UTI (6), and meningitis (1). Eight studies were from Western and Central Africa, 8 from Eastern Africa, and 4 from Southern Africa. Prevalence of Escherichia coli resistance to third-generation cephalosporins ranged from 0% to 75%. No studies reported resistance to carbapenems among Klebsiella spp. Prevalence of fluoroquinolone resistance ranged from 8.3% to 100% among E. coli and 0% to 15% among Salmonella spp. Prevalence of resistance to penicillin among Streptococcus pneumoniae isolates ranged from 25% to 100%. Testing for extended-spectrum beta-lactamase was reported in 7 studies (range, 1.3–60% among tested isolates). Methods for evaluating AMR varied across studies; standardized approaches are needed in the region. Testing for mechanisms of resistance is low even in research settings, but important mechanisms of resistance such as ESBL production are present.

Resistance of Staphylococcus aureus to antimicrobial agents in Ethiopia: a meta-analysis

Background

Emergence of antimicrobial resistance by Staphylococcus aureus has limited treatment options against its infections. The purpose of this study was to determine the pooled prevalence of resistance to different antimicrobial agents by S. aureus in Ethiopia.

Methods

Web-based search was conducted in the databases of PubMed, Google Scholar, Hinari, Scopus and the Directory of Open Access Journals (DOAJ) to identify potentially eligible published studies. Required data were extracted and entered into Excel spread sheet. Statistical analyses were performed using Stata version 13.0. The metaprop Stata command was used to pool prevalence values. Twenty-one separate meta-analysis were done to estimate the pooled prevalence of the resistance of S. aureus to twenty-one different antimicrobial agents. Heterogeneity among the studies was assessed using the I² statistic and chi-square test. Publication bias was assessed using Egger’s test. Because of significant heterogeneity amongst the studies, the random effects model was used to pool prevalence values.

Results

The electronic database search yielded 1317 studies among which 45 studies met our inclusion criteria. Our analyses demonstrated very high level of resistance to amoxicillin (77% [95% confidence interval (CI): 68%, 0.85%]), penicillin (76% [95% CI: 67%, 84%]), ampicillin (75% [95% CI: 65%, 85%]), tetracycline (62% [95% CI: 55%, 68%]), methicillin (47% [95% CI: 33%, 61%]), cotrimoxaziole (47% [95% CI: 40%, 55%]), doxycycline (43% [95% CI: 26%, 60%]), and erythromycin (41% [95% CI: 29%, 54%]). Relatively low prevalence of resistance was observed with kanamycin (14% [95% CI: 5%, 25%]) and ciprofloxacin (19% [95% CI: 13%, 26%]). The resistance level to vancomycin is 11% 995% CI: (4%, 20%). High heterogeneity was observed for each of the meta-analysis performed (I² ranging from 79.36% to 95.93%; all p-values ≤0.01). Eggers’ test did not show a significant publication bias for all antimicrobial agents except for erythromycin and ampicillin.

Conclusions

S. aureus in Ethiopia has gotten notoriously resistant to almost to all of antimicrobial agents in use including, penicillin, cephalosporins, tetracyclines, chloramphenicol, methicillin, vancomycin and sulphonamides. The resistance level to vancomycin is bothersome and requires a due attention. Continued and multidimensional efforts of antimicrobial stewardship program promoting rational use of antibiotics, infection prevention and containment of AMR are urgently needed.

Electronic supplementary material

The online version of this article (doi:10.1186/s13756-017-0243-7) contains supplementary material, which is available to authorized users.

Development and external validation of a clinical prognostic score for death in visceral leishmaniasis patients in a high HIV co-infection burden area in Ethiopia

BACKGROUND

In Ethiopia, case fatality rates among subgroups of visceral leishmaniasis (VL) patients are high. A clinical prognostic score for death in VL patients could contribute to optimal management and reduction of these case fatality rates. We aimed to identify predictors of death from VL, and to develop and externally validate a clinical prognostic score for death in VL patients, in a high HIV co-infection burden area in Ethiopia.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a retrospective cohort study in north west Ethiopia. Predictors with an adjusted likelihood ratio ≥1.5 or ≤0.67 were retained to calculate the predictor score. The derivation cohort consisted of 1686 VL patients treated at an upgraded health center and the external validation cohort consisted of 404 VL patients treated in hospital. There were 99 deaths in the derivation cohort and 53 deaths in the external validation cohort. The predictors of death were: age >40 years (score +1); HIV seropositive (score +1); HIV seronegative (score -1); hemoglobin ≤6.5 g/dl (score +1); bleeding (score +1); jaundice (score +1); edema (score +1); ascites (score +2) and tuberculosis (score +1). The total predictor score per patient ranged from -1 to +5. A score of -1, indicated a low risk of death (1.0%), a score of 0 an intermediate risk of death (3.8%) and a score of +1 to +5, a high risk of death (10.4-85.7%). The area under the receiver operating characteristic curve was 0.83 (95% confidence interval: 0.79-0.87) in derivation, and 0.78 (95% confidence interval: 0.72-0.83) in external validation.

CONCLUSIONS/SIGNIFICANCE

The overall performance of the score was good. The score can enable the early detection of VL cases at high risk of death, which can inform operational, clinical management guidelines, and VL program management. Implementation of focused strategies could contribute to optimal management and reduction of the case fatality rates.

Visceral leishmaniasis treatment outcome and its determinants in northwest Ethiopia

OBJECTIVES

Poor treatment outcomes of visceral leishmaniasis (VL) are responsible for the high mortality rate of this condition in resource-limited settings such as Ethiopia. This study aimed to identify the proportion of poor VL treatment outcomes in northwest Ethiopia and to evaluate the determinants associated with poor outcomes.

METHODS

A hospital-based retrospective study was conducted among 595 VL patients who were admitted to Kahsay Abera Hospital in northwest Ethiopia from October 2010 to April 2013. Data were entered into Epi Info version 7.0 and exported to SPSS version 20 for analysis. Bivariate and multivariate logistic regression models were fitted to identify the determinants of VL treatment outcomes. Adjusted odds ratio (aORs) with 95% confidence intervals (CIs) were used, and p-values <0.05 were considered to indicate statistical significance.

RESULTS

The proportion of poor treatment outcomes was 23.7%. Late diagnosis (≥29 days) (aOR, 4.34; 95% CI, 2.22 to 8.46), severe illness at admission (inability to walk) (aOR, 1.63; 95% CI, 1.06 to 2.40) and coinfection with VL and human immunodeficiency virus (HIV) (aOR, 2.72; 95% CI, 1.40 to 5.20) were found to be determinants of poor VL treatment outcomes.

CONCLUSIONS

Poor treatment outcomes, such as death, treatment failure, and non-adherence, were found to be common. Special attention must be paid to severely ill and VL/HIV-coinfected patients. To improve VL treatment outcomes, the early diagnosis and treatment of VL patients is recommended.

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.

Methicillin resistant Staphylococcus aureus in Ethiopia: a meta-analysis

Background

The burden of methicillin resistant Staphylococcus aureus is a major public health concern worldwide; however the overall epidemiology of multidrug resistant strains is neither coordinated nor harmonized, particularly in developing countries including Ethiopia. Therefore, the aim of this meta-analysis was to assess the burden of methicillin resistant Staphylococcos aureus and its antibiotic resistance pattern in Ethiopia at large.

Methods

PubMed, Google Scholar, and lancet databases were searched and a total of 20 studies have been selected for meta-analysis. Six authors have independently extracts data on the prevalence of methicillin resistant Staphylococcus aureus among clinical isolates of Staphylococcus aureus. Statistical analysis was achieved by using Open meta-analyst (version 3.13) and Comprehensive meta-analysis (version 3.3) softwares. The overall prevalence of methicillin resistant Staphylococcus aureus and its antibiotic resistance pattern were pooled by using the forest plot, table and figure with 95% CI.

Results

The pooled prevalence of methicillin resistant Staphylococcus aureus was 32.5% (95% CI, 24.1 to 40.9%). Moreover, methicillin resistant Staphylococcus aureus strains were found to be highly resistant to penicillin, ampicillin, erythromycin, and amoxicillin, with a pooled resistance ratio of 99.1, 98.1, 97.2 and 97.1%, respectively. On the other hand, comparably low levels of resistance ratio were noted to vancomycin, 5.3%.

Conclusion

The overall burden of methicillin resistant Staphylococcus aureus is considerably high, besides these strains showed extreme resistance to penicillin, ampicillin, erythromycin and amoxicillin. In principle, appropriate use of antibiotics, applying safety precautions are the key to reduce the spread of multidrug resistant strains, methicillin resistant Staphylococcus aureus in particular.

Horizontal transfer of β-carbonic anhydrase genes from prokaryotes to protozoans, insects, and nematodes

BACKGROUND

Horizontal gene transfer (HGT) is a movement of genetic information occurring outside of normal mating activities. It is especially common between prokaryotic endosymbionts and their protozoan, insect, and nematode hosts. Although beta carbonic anhydrase (β-CA) plays a crucial role in metabolic functions of many living organisms, the origin of β-CA genes in eukaryotic species remains unclear.

METHODS

This study was conducted using phylogenetics, prediction of subcellular localization, and identification of β-CA, transposase, integrase, and resolvase genes on the MGEs of bacteria. We also structurally analyzed β-CAs from protozoans, insects, and nematodes and their putative prokaryotic common ancestors, by homology modelling.

RESULTS

Our investigations of a number of target genomes revealed that genes coding for transposase, integrase, resolvase, and conjugation complex proteins have been integrated with β-CA gene sequences on mobile genetic elements (MGEs) which have facilitated the mobility of β-CA genes from bacteria to protozoan, insect, and nematode species. The prokaryotic origin of protozoan, insect, and nematode β-CA enzymes is supported by phylogenetic analyses, prediction of subcellular localization, and homology modelling.

CONCLUSION

MGEs form a complete set of enzymatic tools, which are relevant to HGT of β-CA gene sequences from prokaryotes to protozoans, insects, and nematodes.

Induction of IL-10 and TGFβ from CD4+CD25+FoxP3+ T Cells Correlates with Parasite Load in Indian Kala-azar Patients Infected with Leishmania donovani

Background

Visceral leishmaniasis (VL) is distinguished by a complex interplay of immune response and parasite multiplication inside host cells. However, the direct association between different immunological correlates and parasite numbers remains largely unknown.

Methodology/Principal Findings

We examined the plasma levels of different disease promoting/protective as well as Th17 cytokines and found IL-10, TGFβ and IL-17 to be significantly correlated with parasite load in VL patients (r = 0.52, 0.53 and 0.51 for IL-10, TGFβ and IL-17, respectively). We then extended our investigation to a more antigen-specific response and found leishmanial antigen stimulated levels of both IL-10 and TGFβ to be significantly associated with parasite load (r = 0.71 and 0.72 for IL-10 and TGFβ respectively). In addition to cytokines we also looked for different cellular subtypes that could contribute to cytokine secretion and parasite persistence. Our observations manifested an association between different Treg cell markers and disease progression as absolute numbers of CD4⁺CD25⁺ (r = 0.55), CD4⁺CD25^hi (r = 0.61) as well as percentages of CD4⁺CD25⁺FoxP3⁺ T cells (r = 0.68) all correlated with parasite load. Encouraged by these results, we investigated a link between these immunological components and interestingly found both CD4⁺CD25⁺ and CD4⁺CD25⁺FoxP3⁺ Treg cells to secrete significantly (p<0.05) higher amounts of not only IL-10 but also TGFβ in comparison to corresponding CD25^- T cells.

Conclusions/Significance

Our findings shed some light on source(s) of TGFβ and suggest an association between these disease promoting cytokines and Treg cells with parasite load during active disease. Moreover, the direct evidence of CD4⁺CD25⁺FoxP3⁺ Treg cells as a source of IL-10 and TGFβ during active VL could open new avenues for immunotherapy towards cure of this potentially fatal disease.

Visceral leishmaniasis (VL) is one of the most widespread parasitic diseases worldwide and is caused by kinetoplastid protozoa of the Leishmania donovani complex. The disease begins with internalization of L. donovani parasites and their multiplication within host macrophages followed subsequently by immune suppression. However, the immunological factors responsible for disease progression and their association with parasite dynamics are not completely understood. Herein, we investigated the correlation of different immune components (cytokines and cellular subsets) with parasite load and their involvement in the course of VL. Our study revealed a significant positive correlation between parasite load and plasma as well as antigen specific levels of IL-10 and TGFβ. In addition to cytokines, cellular subsets could also contribute to disease pathogenesis through their regulatory mechanisms. Our results indicate different Treg cell markers (absolute numbers of CD4⁺CD25⁺ and CD4⁺CD25^hi and percentages of CD4⁺CD25⁺FoxP3⁺) to be strongly correlated with parasite load. Exploring an association between these immunological correlates revealed Treg cells to be the source of these cytokines during VL. Therefore, this study points to a significant role of IL-10, TGFβ and Treg cells in parasite load and active VL, providing evidence which could be helpful in devising new immunotherapeutic strategies against this disease.