Ultrasonographic assessment of splenic volume at presentation and after anti-malarial therapy in children with malarial anaemia

The association of intraleucocytic malaria pigment and disease severity in Papua New Guinean children with severe P. falciparum malaria

BACKGROUND

Plasmodium falciparum pigment-containing leucocytes (PCLs) are associated with adverse clinical manifestations of severe malaria in African children. However, limited data exist on the association of PCLs in settings outside of Africa.

METHODS

Thin films on peripheral blood slides obtained from children ages 6 months-10 y with severe malaria were examined for PCLs. The intraleucocytic pigment data were correlated with clinical phenotypic data such as severe anaemia, metabolic acidosis and coma to determine the association of PCLs with clinical phenotypes of severe malaria and outcome.

RESULTS

Of the 169 children with severe P. falciparum malaria confirmed by microscopy, 76% (129/169) had PCLs. Compared with children without PCLs, the presence (adjusted odds ratio [AOR] 3.2 [95% confidence interval {CI} 1.5 to 6.9], p≤0.01) and quantity (AOR 1.0 [95% CI 1.0 to 1.1], p=0.04) of pigment-containing monocytes (PCMs) was significantly associated with severe anaemia, while the quantity of both PCMs (AOR 1.0 [95% CI 1.0 to 1.1], p≤0.01) and pigment-containing neutrophils (AOR 1.0 [95% CI 1.0 to 1.1], p=0.01) was significantly associated with metabolic acidosis. Plasma P. falciparum histidine-rich protein-2 level negatively correlated with the platelet count (r=-0.5, p≤0.01) in patients with PCLs and no PCLs.

CONCLUSIONS

In Papua New Guinean children with severe P. falciparum malaria, the presence and quantity of PCLs are predictors of disease severity, severe anaemia and metabolic acidosis.

PREVALENCE OF PARASITIC INFECTIONS IN CHILDREN OF BOKE, GUINEA

Helminthic and intestinal protozoan infections and malaria infections are common in children less than 15 yr old in sub-Saharan Africa, but little is known about these infections in Guinea. The aim of this study was to determine the prevalence of parasitic infections in children aged less than 15 yr and the relationship of these infections with anemia. The cross-sectional study was done in Dabbis sub-prefecture in the Boke region of Guinea from 18 to 26 March 2017. A simple random sampling at the household level was performed, and 1 child under the age of 15 was included per eligible household. A total of 392 children were included in the analysis. Clinical and parasitological information were assessed, including anthropometric measures (weight and height), disease symptoms, hemoglobin level, and malaria parasitemia. Helminthic and protozoan intestinal infections were present in 59.7% of the children surveyed. Malaria infection prevalence was 45.5% when assessed by microscopy and 43.6% when assessed by a rapid diagnostic test. Plasmodium falciparum, accounting for 84.2% of malaria infections, was the main malaria species infection. Gastrointestinal parasites were present in 19.1% of children. The main gastrointestinal parasites present included Entamoeba coli (5.4%) and Giardia intestinalis (5.1%). There was no association between the presence of anemia and the parasitic status of the children. Parasitic screening and mass treatment in this age group, as well as household awareness raising, would reduce cases of parasitic infections in rural Guinea.

Prevalence of malaria and factors associated with infection in children aged 6 months to 9 years in Guinea: Results from a national cross-sectional study

Worldwide, a child dies every two minutes due to malaria with Africa bearing about 90% of all malaria deaths particularly among children. This study aimed to describe malaria prevalence and its associated factors among children aged 6 months to 9 years in Guinea. We conducted a cross-sectional household survey between 02 and 29 August 2014 in children aged 6 months to 9 years in the four natural regions of the country. A five-level cluster sampling using the national database from the national institute of statistics was used to select study participants. A total of 1984 children aged 6 months to 9 years were enrolled. The mean age was 50 months (SD, 27). The rapid diagnostic test showed a high malaria prevalence (44%) countrywide along with regional variation ranging from 38% to 61%. A multivariate analysis showed that living in Forest Guinea (AOR: 2.48; 95% CI: 1.78–3.46), in rural areas (AOR: 1.91; 95% IC: 1.45–2.5) and having a splenomegaly (AOR: 2.66; 95% CI: 1.75–4.04) were highly associated with malaria. This study shows that malaria is still prevalent in Guinea among children aged 6 months to 9 years of age.

The pathology of the spleen in lethal canine babesiosis caused by Babesia rossi

To provide useful information based on the macropathology, histopathology and immunohistochemical investigation in the spleens of dogs with Babesia rossi infection. Control spleens were collected from four healthy dogs euthanized for welfare reasons. Nine dogs that died naturally because of a mono-infection with Babesia rossi were selected for the diseased group. One haematoxylin-and-eosin-stained section of splenic tissue from each of the infected and control dogs was examined under the light microscope. Immunohistochemical markers were applied to characterize different immunocyte populations. The application of analytic software enabled semi-quantitative comparison of leucocyte subpopulations. Routine splenic histopathology revealed diffuse intermingling of white and red pulp from infected dogs with a clear loss of distinction between these zones. Immunohistochemistry revealed an increase in the proportion of tissue resident and bone marrow origin macrophages in the infected spleens. Apart from a few remnant lymphocytes within the peri-arteriolar lymphatic sheaths and follicles, the majority of the immunocytes redistributed to the red pulp, supporting the observation of white and red pulp intermingling. The majority of our findings are in agreement with histomorphological descriptions of the spleen in a variety of noncanid mammalian hosts with lethal malaria or babesiosis.

Differential impact of malaria control interventions on P. falciparum and P. vivax infections in young Papua New Guinean children

INTRODUCTION

As malaria transmission declines, understanding the differential impact of intensified control on Plasmodium falciparum relative to Plasmodium vivax and identifying key drivers of ongoing transmission is essential to guide future interventions.

METHODS

Three longitudinal child cohorts were conducted in Papua New Guinea before (2006/2007), during (2008) and after scale-up of control interventions (2013). In each cohort, children aged 1-5 years were actively monitored for infection and illness. Incidence of malaria episodes, molecular force of blood-stage infections (_molFOB) and population-averaged prevalence of infections were compared across the cohorts to investigate the impact of intensified control in young children and the key risk factors for malaria infection and illness in 2013.

RESULTS

Between 2006 and 2008, P. falciparum infection prevalence, _molFOB, and clinical malaria episodes reduced by 47%, 59% and 69%, respectively, and a further 49%, 29% and 75% from 2008 to 2013 (prevalence 41.6% to 22.1% to 11.2%; _molFOB: 3.4 to 1.4 to 1.0 clones/child/year; clinical episodes incidence rate (IR) 2.6 to 0.8 to IR 0.2 episodes/child/year). P. vivax clinical episodes declined at rates comparable to P. falciparum between 2006, 2008 and 2013 (IR 2.5 to 1.1 to 0.2), while P. vivax _molFOB (2006, 9.8; 2008, 12.1) and prevalence (2006, 59.6%; 2008, 65.0%) remained high in 2008. However, in 2013, P. vivax _molFOB (1.2) and prevalence (19.7%) had also substantially declined. In 2013, 89% of P. falciparum and 93% of P. vivax infections were asymptomatic, 62% and 47%, respectively, were sub-microscopic. Area of residence was the major determinant of malaria infection and illness.

CONCLUSION

Intensified vector control and routine case management had a differential impact on rates of P. falciparum and P. vivax infections but not clinical malaria episodes in young children. This suggests comparable reductions in new mosquito-derived infections but a delayed impact on P. vivax relapsing infections due to a previously acquired reservoir of hypnozoites. This demonstrates the need to strengthen implementation of P. vivax radical cure to maximise impact of control in co-endemic areas. The high heterogeneity of malaria in 2013 highlights the importance of surveillance and targeted interventions to accelerate towards elimination.

Is there a role for bedside ultrasound in malaria? A survey of the literature

PURPOSE

Point-of-care ultrasound (POCUS) has proven utility in the evaluation and treatment of many tropical diseases. Its role in malaria has been studied, but its value for the clinician at the bedside is unclear. Our review aimed at summarizing the existing studies to assess the usefulness, if any, of POCUS in treating malaria.

METHODS

We used Boolean operators using keywords "malaria", "acoustic", "ultrasound", "echography", and "ultrasonography" to search PubMed, Scopus, and Science Direct in three languages (Italian, French, and English).

RESULTS

We found 22 eligible references. Organs explored include the liver, spleen, heart, optic nerve sheath diameter (ONSD), kidney, lungs, and cerebral vasculature. Multiple pathologic findings by ultrasound are reported, but few demonstrate clinical utility. Current studies involve small numbers of patients, and a few trends emerge when studies are compared. The ability to combine study results is limited due to the significant heterogeneity that exists between studies in regards to both methods of evaluation and the reporting of organ pathology and malaria severity.

CONCLUSIONS AND ASSESSMENT

A review of the current literature indicates that the use of ultrasound by clinicians adds little to the diagnostic evaluation of patients with malaria. Our review did find that measurements of the spleen, lungs, optic nerve sheath diameter, and cerebral blood flow have potential utility in specific patient populations. Further studies are needed to evaluate whether this utility persists when a larger sample size is used.

A clinical severity scoring system for visceral leishmaniasis in immunocompetent patients in South Sudan

Background

South Sudan is one of the most endemic countries for visceral leishmaniasis (VL), and is frequently affected by large epidemics. In resource-limited settings, clinicians require a simple clinical tool to identify VL patients who are at increased risk of dying, and who need specialised treatment with liposomal amphotericin B and other supportive care. The aim of this study was to develop and validate a clinical severity scoring system based on risk factors for death in VL patients in South Sudan.

Methods

A retrospective analysis was conducted of data from a cohort of 6,633 VL patients who were treated in the Médecins Sans Frontières (MSF) hospital in Lankien between July 2013 and June 2015. Risk factors for death during treatment were identified using multivariable logistic regression models, and the regression coefficients were used to develop a severity scoring system. Sensitivity and specificity of score cut-offs were assessed by receiver operating characteristic (ROC) analysis.

Results

In multivariable models, risk factors for death in adult VL patients were: anaemia (odds ratio (OR) 4.46 (95% CI 1.58–12.6) for Hb <6g/dL compared with ≥9g/dL), nutritional status (OR 4.84 (2.09–11.2) for BMI <13 kg/m² compared with ≥16 kg/m²), weakness (OR 4.20 (1.82–9.73) for collapsed compared with normal weakness), jaundice (OR 3.41 (1.17–9.95)), and oedema/ascites (OR 4.86 (1.67–14.1)). For children and adolescents the risk factors were: age (OR 10.7 (6.3–18.3) for age <2 years compared with 6–18 years), anaemia (OR 7.76 (4.15–14.5) for Hb <6g/dL compared with ≥9g/dL), weakness (OR 3.13 (22.8–105.2) for collapsed compared with normal weakness), and jaundice (OR 12.8 (4.06–40.2)). Severity scoring predictive ability was 74.4% in adults and 83.4% in children and adolescents.

Conclusion

Our evidenced-based severity scoring system demonstrated sufficient predictive ability to be operationalised as a clinical tool for rational allocation of treatment to VL patients at MSF centres in South Sudan.

Visceral leishmaniasis (VL), also known as kala-azar, is a neglected tropical disease caused by a parasite (Leishmania) and transmitted to humans through the bite of a sandfly. South Sudan is one of the highest endemic countries for VL, frequently affected by epidemics. In South Sudan are different treatment options for VL available: the standard therapy given on ambulatory bases by intramuscular injections for 17 days, and specialized treatment for patients with severe VL, administered intravenously in a hospital over 12 days. In the extremely resource limited context of South Sudan, the most optimal treatment to patients with severe VL should be provided, but a rational use of drugs maintained. In this study, we identified risk factors for death in VL patients of South Sudan, and based on these risk factors we developed a severity scoring system. This severity scoring system will be a clinical decision making tool for allocation of VL patients to the appropriate treatment and to minimise the mortality of the VL patients in South Sudan.

Noncirrhotic Portal Fibrosis in Pediatric Population

OBJECTIVES

Noncirrhotic portal fibrosis (NCPF) has been classically described as a disease of young to middle age with limited literature regarding its occurrence, onset, or clinical presentation in children. We hereby present a series of 19 patients diagnosed and managed as NCPF in pediatric age group.

METHODS

A retrospective review of all the patients presenting to the pediatric hepatology department (age <18 years) and diagnosed as NCPF was done and data were evaluated.

RESULTS

A total of 19 patients were diagnosed as NCPF with median age at onset of symptoms and diagnosis as 10 years and 13.8 years respectively. Majority presented with left upper quadrant discomfort or mass. Laboratory parameters showed hypersplenism in majority with preserved liver synthetic functions. Median values for hepatic venous pressure gradient and liver stiffness measurement were 13.5 mmHg and 10.6 kPa, respectively. Classical hepatic histopathological features seen were maintained lobular architecture, atretic portal tracts, approximation of portal-portal and portal-central areas, and aberrant peripheral portal channels. During follow-up, majority of the patients did not show disease progression.

CONCLUSIONS

NCPF is not an uncommon entity in pediatric population with age of onset in early second decade. Hepatic histopathology must be used to exclude cirrhosis and to confirm the diagnosis. Hepatic venous pressure gradient and liver stiffness measurement values, in some cases, may overlap with those in patients with cirrhosis and may not be diagnostic in isolation. Any patient presenting with evidence of portal hypertension with preserved hepatic functions, irrespective of the age, should be evaluated for possible NCPF.

Does coronal oblique length of spleen on CT reflect splenic index?

AIMS AND OBJECTIVES

Splenic dimension of >12 cm on coronal plane on ultrasound is considered to represent splenomegaly. We sought to estimate the accuracy of similar coronal oblique length of spleen on CT in identifying splenomegaly by comparing it with CT splenic index. We also sought to establish the splenic width, craniocaudal dimension (CC), thickness, and coronal oblique length in both normal and splenomegaly groups.

MATERIALS AND METHODS

319 consecutive patients undergoing CT abdomen were included in the study and measurements of width (W), CC, thickness (T), and coronal oblique length (L) made. Splenic index was calculated based on the formula CC × W × T. Diagnostic accuracy of coronal oblique length in identifying splenomegaly on the basis of splenic index was assessed. Patients with splenic trauma were excluded. Patients with perisplenic collection that precluded proper measurement of spleen were excluded.

RESULTS

Of the 319 patients, 41 patients had splenomegaly with splenic index >480. 278 patients showed normal splenic index less than or equal to 480. Sensitivity and specificity of coronal oblique length as ≥12 cm in identifying splenomegaly were 97.8% and 34.1%, respectively. Positive and negative predictive values for the same were 91% and 70%, respectively (p value-0.000). There is overlap of numerical values for thickness and coronal oblique length in the normal and splenomegaly groups for a 95% confidence interval, whereas there is no significant overlap between these groups with respect to the craniocaudal length and width. Hence, craniocaudal length of 9.5 cm and width of 10.6 cm may be used as upper cutoff limit for normal spleen.

CONCLUSION

Coronal oblique dimension of spleen >12 cm is highly sensitive and shows good positive predictive value in diagnosing splenomegaly but has poor specificity and negative predictive value. Ideally, splenic index calculated using the CC, width, and thickness is the most reliable measurement for diagnosing splenomegaly. But if single measurements are to be used for identifying splenomegaly, craniocaudal length >9.5 cm, width of >10.6 cm, and coronal oblique dimension >12 cm may be used.