Eosinophilia in Infectious Diseases

Insights into the epidemiology, pathogenesis, and differential diagnosis of schistosomiasis

Schistosomiasis is a neglected tropical disease that is prevalent in low- and middle-income countries. There are five human pathogenic species, of which Schistosoma haematobium, Schistosoma mansoni and Schistosoma japonicum are the most prevalent worldwide and cause the greatest burden of disease in terms of mortality and morbidity. In addition, hybrid schistosomes have been identified through molecular analysis. Human infection occurs when cercariae, the larval form of the parasite, penetrate the skin of people while bathing in contaminated waters such as lakes and rivers. Schistosomiasis can cause both urogenital and intestinal symptoms. Urogenital symptoms include haematuria, bladder fibrosis, kidney damage, and an increased risk of bladder cancer. Intestinal symptoms may include abdominal pain, sometimes accompanied by diarrhoea and blood in the stool. Schistosomiasis affects more than 250 million people and causes approximately 70 million Disability-Adjusted Life Years (DALYs), mainly in Africa, South America, and Asia. To control infection, it is essential to establish sensitive and specific diagnostic tests for epidemiological surveillance and morbidity reduction. This review provides an overview of schistosomiasis, with a focus on available diagnostic tools for Schistosoma spp. Current molecular detection methods and progress in the development of new diagnostics for schistosomiasis infection are also discussed.

The challenge of diagnosing and classifying eosinophilia and eosinophil disorders: A review

Eosinophilia is a feature of multiple conditions, both hematologic and non-hematologic, and may be associated with organ damage. The pathogenesis of eosinophilia can follow two distinct pathways. Primary eosinophilia is caused by a cell-intrinsic mechanism originating from clonal expansion of eosinophils through acquisition of a somatic mutation, such as FIP1L1-PDGFRA. In recent years, great progress has been made in the field of pathogenesis and molecularly targeted therapy of neoplastic eosinophilia. The diagnostic procedure should include, among other things, morphologic analysis of blood and bone marrow samples, cytogenetics and fluorescence in situ-hybridization tests to detect evidence of an acute or chronic myeloid or lymphoid disorder. Secondary eosinophilia follows a cell-extrinsic mechanism as a response to exogenous cytokines. In most clinical cases, peripheral blood eosinophilia is reactive and typically associated with non-hematological disorders such as infections, allergic conditions, connective tissue disorders, vasculitis, malignancy, or endocrinopathies. Nonetheless, the cause of most cases of hypereosinophilic syndrome remains unknown. In this article, we present a short review focused on differential diagnosis of eosinophilia and eosinophilic disorders. The diagnosis of eosinophilia is a challenge for physicians; thus this review may be useful in clinical practice.

Clinical and Therapeutic Intervention of Hypereosinophilia in the Era of Molecular Diagnosis

Hypereosinophilia (HE) presents with an elevated peripheral eosinophilic count of >1.5 × 109/L and is composed of a broad spectrum of secondary non-hematologic disorders and a minority of primary hematologic processes with heterogenous clinical presentations, ranging from mild symptoms to potentially lethal outcome secondary to end-organ damage. Following the introduction of advanced molecular diagnostics (genomic studies, RNA sequencing, and targeted gene mutation profile, etc.) in the last 1-2 decades, there have been deep insights into the etiology and molecular mechanisms involved in the development of HE. The classification of HE has been updated and refined following to the discovery of clinically novel markers and targets in the 2022 WHO classification and ICOG-EO 2021 Working Conference on Eosinophil Disorder and Syndromes. However, the diagnosis and management of HE is challenging given its heterogeneity and variable clinical outcome. It is critical to have a diagnostic algorithm for accurate subclassification of HE and hypereosinophilic syndrome (HES) (e.g., reactive, familial, idiopathic, myeloid/lymphoid neoplasm, organ restricted, or with unknown significance) and to follow established treatment guidelines for patients based on its clinical findings and risk stratification.

A Predictive Algorithm for Discriminating Myeloid Malignancies and Leukemoid Reactions

BACKGROUND

Adults presenting with a neutrophil-predominant leukocytosis (white cell count >50,000/μL) often necessitate urgent medical management. These patients are diagnosed with either acute presentations of chronic myeloid malignancies or leukemoid reactions, yet accurate models to distinguish between these entities do not exist. We used demographic and lab data to build a machine learning model capable of discriminating between these diagnoses.

METHODS

The medical record at a tertiary care medical center was queried to identify adults with instances of white counts greater than 50,000/μL and >50% neutrophils from 2000 to 2021. For each patient, a full set of demographic and lab values were extracted at the time of their first presentation with a white count >50,000/μL. We generated a series of models in which the parameters most predictive of myeloid malignancies were identified, and a supervised machine learning approach was applied to the dataset.

RESULTS

Our best model-using a support vector machine algorithm-produced a sensitivity of 96% and a specificity of 95.9% (area under the curve = 0.982) for identifying myeloid malignancies. We also identified a clinically meaningful and significant disparity in outcomes based on diagnosis-a 6-fold increase in 12-month mortality in those diagnosed with leukemoid reactions.

CONCLUSIONS

These findings need to be validated but fill an unmet need for timely and accurate diagnosis in the setting of profound, neutrophil-predominant leukocytosis and support the use of predictive models as a means to improve patient outcomes.

Joint ESPGHAN/NASPGHAN Guidelines on Childhood Eosinophilic Gastrointestinal Disorders Beyond Eosinophilic Esophagitis

INTRODUCTION

Eosinophilic gastrointestinal disorders beyond eosinophilic esophagitis (non-EoE EGIDs) are rare chronic inflammatory disorders of the gastrointestinal (GI) tract. Diagnosis is based on clinical symptoms and histologic findings of eosinophilic inflammation after exclusion of a secondary cause or systemic disease. Currently, no guidelines exist for the evaluation of non-EoE EGIDs. Therefore, the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) formed a task force group to provide consensus guidelines for childhood non-EoE EGIDs.

METHODS

The working group was composed of pediatric gastroenterologists, adult gastroenterologists, allergists/immunologists, and pathologists. An extensive electronic literature search of the MEDLINE, EMBASE, and Cochrane databases was conducted up to February 2022. General methodology was used in the formulation of recommendations according to the Appraisal of Guidelines for Research and Evaluation (AGREE) II and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to meet current standards of evidence assessment.

RESULTS

The guidelines provide information on the current concept of non-EoE EGIDs, disease pathogenesis, epidemiology, clinical manifestations, diagnostic and disease surveillance procedures, and current treatment options. Thirty-four statements based on available evidence and 41 recommendations based on expert opinion and best clinical practices were developed.

CONCLUSION

Non-EoE EGIDs literature is limited in scope and depth, making clear recommendations difficult. These consensus-based clinical practice guidelines are intended to assist clinicians caring for children affected by non-EoE EGIDs and to facilitate high-quality randomized controlled trials of various treatment modalities using standardized, uniform disease definitions.

Human gnathostomiasis: A review on the biology of the parasite with special reference on the current therapeutic management

Gnathostoma is a parasitic nematode that can infect a wide range of animal species, but human populations have become accidental hosts because of their habit of eating raw or undercooked meat from a wide variety of intermediate hosts. While gnathostomiasis is considered an endemic disease, cases of human gnathostomiasis have been increasing over time, most notably in nonendemic areas. There are several complexities to this parasitic disease, and this review provides an update on human gnathostomiasis, including the life cycle, diagnosis, treatment, and treatment strategies used to combat drug resistance. Even now, a definitive diagnosis of gnathostomiasis is still challenging because it is difficult to isolate larvae for parasitological confirmation. Another reason is the varying clinical symptoms recorded in reported cases. Clinical cases can be confirmed by immunodiagnosis. For Gnathosotoma spinigerum, the detection of IgG against a specific antigenic band with a molecular weight of 24 kDa from G. spinigerum advanced third-stage larvae (aL3), while for other species of Gnathostoma including G. binucleatum, the 33-kDa antigen protein is being used. This review also discusses cases of recurrence of gnathostomiasis and resistance mechanisms to two effective chemotherapeutics (albendazole and ivermectin) used against gnathostomiasis. This is significant, especially when planning strategies to combat anthelmintic resistance. Lastly, while no new chemotherapeutics against gnathostomiasis have been made available, we describe the management of recurrent gnathostomiasis using albendazole and ivermectin combinations or extensions of drug treatment plans.

Eosinophils-from cradle to grave: An EAACI task force paper on new molecular insights and clinical functions of eosinophils and the clinical effects of targeted eosinophil depletion

Over the past years, eosinophils have become a focus of scientific interest, especially in the context of their recently uncovered functions (e.g. antiviral, anti-inflammatory, regulatory). These versatile cells display both beneficial and detrimental activities under various physiological and pathological conditions. Eosinophils are involved in the pathogenesis of many diseases which can be classified into primary (clonal) and secondary (reactive) disorders and idiopathic (hyper)eosinophilic syndromes. Depending on the biological specimen, the eosinophil count in different body compartments may serve as a biomarker reflecting the underlying pathophysiology and/or activity of distinct diseases and as a therapy-driving (predictive) and monitoring tool. Personalized selection of an appropriate therapeutic strategy directly or indirectly targeting the increased number and/or activity of eosinophils should be based on the understanding of eosinophil homeostasis including their interactions with other immune and non-immune cells within different body compartments. Hence, restoring as well as maintaining homeostasis within an individual's eosinophil pool is a goal of both specific and non-specific eosinophil-targeting therapies. Despite the overall favourable safety profile of the currently available anti-eosinophil biologics, the effect of eosinophil depletion should be monitored from the perspective of possible unwanted consequences.

Review of Toxocariasis at a Children's Hospital Prompting Need for Public Health Interventions

BACKGROUND

Toxocariasis, caused the by dog and cat roundworm, is one of the most common zoonotic helminth infections in the United States and can lead to severe lifelong morbidity in children. Although historical seroprevalence studies have identified a high frequency of toxocariasis regionally in the United States, there are few studies linking epidemiology and clinical disease in children. The study objective was to examine the contemporary epidemiology of pediatric toxocariasis within an endemic US region.

METHODS

We conducted an epidemiologic study analyzing children diagnosed with toxocariasis presenting to a tertiary pediatric hospital in Texas from 2010 to 2021. We examined risk factors and performed a geospatial analysis, including a comparative analysis of human cases and locations of surrendered infected stray animals in the same region.

RESULTS

Children diagnosed with toxocariasis were most commonly of Hispanic/Latino ethnicity (30/46; 65%), white race (41/45; 91%) and receiving Medicaid (34/44, 77%). Many infected children had contact with dogs or cats. Ocular toxocariasis was associated with a lack of peripheral eosinophilia ( P < 0.001). No other Toxocara syndromes were associated with defined absolute eosinophil count levels. Post-treatment resolution of eosinophilia was variable, ranging from 1 to 172 weeks. A Toxocara hotspot was identified in northeast Houston, comprising one of the lowest median household incomes in the region.

CONCLUSIONS

Toxocariasis is a devastating zoonotic infection in children living in the US. As it is not a reportable disease, the true burden remains unknown. It is critical to increase awareness of toxocariasis to direct public health interventions and ultimately reduce Toxocara -induced morbidity in US children.

Case report: Probable toxocariasis in a Swiss adult patient with hypereosinophilic syndrome and multiorgan involvement

Hypereosinophilic syndromes are a heterogeneous group of rare diseases characterized by eosinophil-related organ damage and peripheral blood hypereosinophilia. Hypereosinophilic syndromes may occur secondary to a variety of clinical entities, for example, drug hypersensitivity reactions, parasitic infections, autoimmune disorders, and malignancies. Toxocariasis is a parasitic infection caused by the larval stage of the Toxocara species. It is usually a childhood disease and invades organs such as the liver but can affect any organ. Hypereosinophilic syndrome and multiorgan involvement are very rare manifestations of Toxocara infection, especially in adults. However, the disease may be underdiagnosed because of different factors, including a lack of laboratory infrastructure in some countries, a lack of uniform case definitions, and limited surveillance infrastructure, with its estimation constituting a challenge. We, therefore, present a probable case of hypereosinophilic syndrome with multiorgan involvement secondary to infection with Toxocara canis in a 79-year-old Swiss female patient with a medical history of ischemic cerebrovascular insult and a curatively resected non-small-cell bronchial carcinoma, successfully treated with albendazole and steroids.

Intestinal helminthic infections: a narrative review to guide the hepatogastroenterologist

Intestinal helminthic infections are not uncommon in Western Europe, mainly due to modern travel, emigration and globalization. Moreover, some helminthic infections are endemic in Western Europe and are part of the everyday clinical practice. The hepatogastroenterologist should therefore recognize and manage these patients or at least refer them to appropriate reference centers. Signs and symptoms are often unspecific or even absent. Discerning the disease at an early stage avoids expensive diagnostic testing, life-threatening complications and in some cases even further spread of the disease. This review article aims to guide the hepatogastroenterologist when suspecting a helminthic infection by addressing the most prevalent symptoms, summarizing the most probable associated helminthic entities, highlighting practical steps in diagnosis and available treatments.

The multidisciplinary approach to eosinophilia

Eosinophilic granulocytes are normally present in low numbers in the bloodstream. Patients with an increased number of eosinophilic granulocytes in the differential count (eosinophilia) are common and can pose a clinical challenge because conditions with eosinophilia occur in all medical specialties. The diagnostic approach must be guided by a thorough medical history, supported by specific tests to guide individualized treatment. Neoplastic (primary) eosinophilia is identified by one of several unique acquired genetic causes. In contrast, reactive (secondary) eosinophilia is associated with a cytokine stimulus in a specific disease, while idiopathic eosinophilia is a diagnosis by exclusion. Rational treatment is disease-directed in secondary cases and has paved the way for targeted treatment against the driver in primary eosinophilia, whereas idiopathic cases are treated as needed by principles in eosinophilia originating from clonal drivers. The vast majority of patients are diagnosed with secondary eosinophilia and are managed by the relevant specialty-e.g., rheumatology, allergy, dermatology, gastroenterology, pulmonary medicine, hematology, or infectious disease. The overlap in symptoms and the risk of irreversible organ involvement in eosinophilia, irrespective of the cause, warrants that patients without a diagnostic clarification or who do not respond to adequate treatment should be referred to a multidisciplinary function anchored in a hematology department for evaluation. This review presents the pathophysiology, manifestations, differential diagnosis, diagnostic workup, and management of (adult) patients with eosinophilia. The purpose is to place eosinophilia in a clinical context, and therefore justify and inspire the establishment of a multidisciplinary team of experts from diagnostic and clinical specialties at the regional level to support the second opinion. The target patient population requires highly specialized laboratory analysis and therapy and occasionally has severe eosinophil-induced organ dysfunction. An added value of a centralized, clinical function is to serve as a platform for education and research to further improve the management of patients with eosinophilia. Primary and idiopathic eosinophilia are key topics in the review, which also address current research and discusses outstanding issues in the field.

Induction of Siglec-FhiCD101hi eosinophils in the lungs following murine hookworm Nippostrongylus brasiliensis infection

Helminth-induced eosinophils accumulate around the parasite at the site of infection, or in parasite-damaged tissues well after the helminth has left the site. The role of helminth-elicited eosinophils in mediating parasite control is complex. While they may contribute to direct parasite-killing and tissue repair, their involvement in long-term immunopathogenesis is a concern. In allergic Siglec-F^hiCD101^hi, eosinophils are associated with pathology. Research has not shown if equivalent subpopulations of eosinophils are a feature of helminth infection. In this study, we demonstrate that lung migration of rodent hookworm Nippostrongylus brasiliensis (Nb) results in a long-term expansion of distinct Siglec-F^hiCD101^hi eosinophil subpopulations. Nb-elevated eosinophil populations in the bone marrow and circulation did not present this phenotype. Siglec-F^hiCD101^hi lung eosinophils exhibited an activated morphology including nuclei hyper-segmentation and cytoplasm degranulation. Recruitment of ST2⁺ ILC2s and not CD4⁺ T cells to the lungs was associated with the expansion of Siglec-F^hiCD101^hi eosinophils. This data identifies a morphologically distinct and persistent subset of Siglec-F^hiCD101^hi lung eosinophils induced following Nb infection. These eosinophils may contribute to long-term pathology following helminth infection.

COVID-19 morbidity in lower versus higher income populations underscores the need to restore lost biodiversity of eukaryotic symbionts

The avoidance of infectious disease by widespread use of 'systems hygiene', defined by hygiene-enhancing technology such as sewage systems, water treatment facilities, and secure food storage containers, has led to a dramatic decrease in symbiotic helminths and protists in high-income human populations. Over a half-century of research has revealed that this 'biota alteration' leads to altered immune function and a propensity for chronic inflammatory diseases, including allergic, autoimmune and neuropsychiatric disorders. A recent Ethiopian study (EClinicalMedicine 39: 101054), validating predictions made by several laboratories, found that symbiotic helminths and protists were associated with a reduced risk of severe COVID-19 (adjusted odds ratio = 0.35; p<0.0001). Thus, it is now apparent that 'biome reconstitution', defined as the artificial re-introduction of benign, symbiotic helminths or protists into the ecosystem of the human body, is important not only for alleviation of chronic immune disease, but likely also for pandemic preparedness.

Reference Intervals and Percentiles for Hematologic and Serum Biochemical Values in Captive Bred Rhesus (Macaca mulatta) and Cynomolgus Macaques (Macaca fascicularis)

Several physiological characteristics and housing conditions are known to affect hematologic and serum biochemical values in macaques. However, the studies that have been conducted either report values calculated based on a small number of animals, were designed specifically to document the effect of a particular condition on the normal range of hematologic and serum biochemical values, or used parametric assumptions to calculate hematologic and serum biochemical reference intervals. We conducted a retrospective longitudinal cohort study to estimate reference intervals for hematologic and serum biochemical values in clinically healthy macaques based on observed percentiles without parametric assumptions. Data were obtained as part of the Biomedical Primate Research Centre (Rijswijk, The Netherlands) health monitoring program between 2018 and 2021. In total, 4009 blood samples from 1475 macaques were analyzed with a maximum of one repeat per year per animal. Data were established by species, gender, age, weight-for-height indices, pregnancy, sedation protocol, and housing conditions. Most of the parameters profoundly affected just some hematologic and serum biochemical values. A significant glucose difference was observed between the ketamine and ketamine-medetomidine sedation protocols. The results emphasize the importance of establishing uniform experimental groups with validated animal husbandry and housing conditions to improve the reproducibility of the experiments.

Opportunistic etiological agents causing lung infections: emerging need to transform lung-targeted delivery

Lung diseases continue to draw considerable attention from biomedical and public health care agencies. The lung with the largest epithelial surface area is continuously exposed to the external environment during exchanging gas. Therefore, the chances of respiratory disorders and lung infections are overgrowing. This review has covered promising and opportunistic etiologic agents responsible for lung infections. These pathogens infect the lungs either directly or indirectly. However, it is difficult to intervene in lung diseases using available oral or parenteral antimicrobial formulations. Many pieces of research have been done in the last two decades to improve inhalable antimicrobial formulations. However, very few have been approved for human use. This review article discusses the approved inhalable antimicrobial agents (AMAs) and identifies why pulmonary delivery is explored. Additionally, the basic anatomy of the respiratory system linked with barriers to AMA delivery has been discussed here. This review opens several new scopes for researchers to work on pulmonary medicines for specific diseases and bring more respiratory medication to market.

Dirofilarial nodule as a differential diagnosis for subcutaneous lumps in children

PURPOSE

Subcutaneous nodules in children are commonly caused by pilomatrixoma, dermoid cysts, soft tissue tumors, etc. Parasitic infections are reported to cause subcutaneous nodules and are infrequently described, mostly in the adult literature. We aim to describe the clinicopathological features of subcutaneous lumps caused by dirofilarial infestation in children in an endemic country.

METHODS

A retrospective analysis was performed of all patients presenting with the above condition to Lady Ridgeway Hospital from 2018 to 2022 and their relevant details were captured in a proforma.

RESULTS

There were 55 patients with a male to female ratio of 2:1. The mean age at presentation was 50 months (7-156 months). The mean duration was 97 days (1-820 days). The common sites involved were scrotum (30.9%), back (14.5%), abdominal wall (102.7%) and face (10.9%). The majority had a painless nodule (70.9%), while ten (18.2%) had features of acute inflammation. Thirty (55.5%) had preoperative ultrasonography which showed features of parasitic nodules in 26 (47.3%). Parasite was demonstrated in histopathological analysis only in 30 patients (54.5%).

CONCLUSION

Dirofilarial nodule should be considered in the differential diagnosis of subcutaneous lumps in children, especially in the endemic areas.

Concomitant intramyocardial and hepatic hydatid cysts diagnosed by multi-modality imaging: A rare case report

Cardiac echinococcosis is a potentially fatal form of hydatid disease; yet, its diagnosis and treatment are challenging due to the variability in its clinical manifestations and due to its various unpredictable preoperative complications. Multi-modality imaging is shown to provide important guidance for the treatment and decision-making. We report a rare case of a 50-year-old woman who had concomitant cardiac and hepatic hydatid cysts. She presented with abdominal pain and elevated eosinophilic white blood cells. The initial abdominal ultrasound and computerized tomography revealed a large cyst in the liver. An intramyocardial cyst was detected by two-dimensional echocardiography. Three-dimensional echocardiography increased the confidence level of two-dimensional echocardiography by displaying the three-dimensional volume of the cyst and allowing visualization of its spatial characteristics and the relationships with adjacent cardiac structures, which was subsequently confirmed at surgery. Multi-detector computed tomography and magnetic resonance imaging helped localize and define the typical morphological features of the cyst. Serology and antigen detection were used for diagnosis. This rare case underlines the integration of clinical, multi-modality imaging, and pathological data in the diagnosis of concomitant intramyocardial and hepatic hydatid cysts. Surgical resection of cysts and anthelmintic medication were successful in the management of this patient.

Approach to the patient with suspected hypereosinophilic syndrome

Hypereosinophilic syndromes (HES) are a heterogenous group of rare disorders with clinical manifestations ranging from fatigue to life-threatening endomyocardial fibrosis and thromboembolic events. Given the broad differential diagnosis of HES, a comprehensive approach is needed to identify potential secondary (treatable) causes and define end-organ manifestations. Classification by clinical HES subtype is also useful in terms of assessing prognosis and guiding therapy. Corticosteroids remain the mainstay of initial therapy in the setting of acute, life-threatening PDGFR mutation-negative HES. Whereas the recent availability of eosinophil-targeted therapies with extraordinary efficacy and little apparent toxicity is changing the treatment paradigm, especially for idiopathic HES and overlap syndromes, questions remain unanswered regarding the choice of agent, impact of combination therapies, and long-term effects of eosinophil depletion. This review provides a case-based discussion of the differential diagnosis of HES, including the classification by clinical HES subtype. Treatment options are reviewed, including novel eosinophil-targeted agents recently approved for the treatment of HES and/or other eosinophil-associated disorders. Primary (myeloid) disorders associated with hypereosinophilia are not be addressed in depth in this review.

Prevalence and Associated Factors of Blastocystis sp. Infection in Patients with Gastrointestinal Symptoms in Spain: A Case-Control Study

Blastocystis sp. is known to be the most prevalent parasite in fecal samples of humans worldwide. In the present report, a case–control study (1:9.89 (≈10)) was performed, by analyzing data from 3682 patients who attended a public hospital in the northern area of Spain showing gastrointestinal symptoms. Diagnosis was performed in human fecal samples by means of optical microscopy. The prevalence of Blastocystis sp. in patients with gastrointestinal symptoms was 9.18% (338/3682). Most of the Blastocystis sp.-infected patients tested negative for protozoa and helminths, and were underweight and foreign-born (26.4%), mainly from Africa and Central/South America. Gastrointestinal symptoms, such as abdominal pain, anorexia, halitosis, plus relative eosinophilia, as well as co-infections with pathogenic bacteria were associated with Blastocystis sp. infection. Both type 2 diabetes and treatment with immunosuppressive medicines at the time of Blastocystis sp. detection were associated with a higher proportion of infected patients. This is the first case–control study of Blastocystis sp. in humans in northern Spain and may contribute to surveillance and intervention strategies by public health authorities.

A diagnostic score for eosinophilic granulomatosis with polyangiitis among eosinophilic disorders

BACKGROUND

Eosinophilic granulomatosis with polyangiitis (EGPA) is a form of systemic vasculitis with eosinophilic inflammation. However, existing classification criteria are all designed to classify EGPA among vasculitis and there is no established method distinguishing EGPA from other eosinophilic disorders. The aim of the present study was to propose a scoring system to differentiate EGPA among eosinophilic disorders.

METHODS

Non-supervised hierarchical clustering using Ward's method and principal component analysis (PCA) were performed for 19 clinical parameters of 58 patients with eosinophilia-related diseases at a tertiary university hospital. The newly proposed scoring system was externally validated in 40 patients at another tertiary institution.

RESULTS

Two distinct clusters were identified, and clinical features including peripheral neuropathy, asthma, skin involvement, lung involvement, rheumatoid factor (RF) positivity, myeloperoxidase (MPO)-anti-neutrophil cytoplasmic antibody (ANCA) positivity, IgE elevation, C-reactive protein (CRP) elevation, and vasculitis pathological findings were predominantly observed in one of these clusters (p < 0.05). Ten features defining the cluster with a high rate of vasculitis were weighted by PCA to create the E-CASE (EGPA classification among systemic eosinophilia) scoring system, on a 16-point scale. Based on the distribution of scores in the primary cohort, we defined an E-CASE score ≥12 as positive, ≤ 8 as negative, and 9-11 as undeterminable. The sensitivity and specificity of the E-CASE score in the validation cohort were 93.3% and 100%, respectively.

CONCLUSIONS

We developed and verified a novel scoring system for differentiating EGPA from other types of eosinophilic disorders.

Epidemiological characteristics of P. vivax asymptomatic infections in the Peruvian Amazon

Introduction

Herein, we tested the hypothesis that Asymptomatic P. vivax (Pv) infected individuals (Asym) feature different epidemiological, clinical and biochemical characteristics, as well as hematological parameters, potentially predictive of clinical immunity in comparison to symptomatic Pv infected individuals (Sym).

Methodology

Between 2018 - 2021, we conducted 11 population screenings (PS, Day 0 (D0)) in 13 different riverine communities around Iquitos city, in the Peruvian Amazon, to identify Pv Sym and Asym individuals. A group of these individuals agreed to participate in a nested case - control study to evaluate biochemical and hematological parameters. Pv Asym individuals did not present common malaria symptoms (fever, headache, and chills), had a positive/negative microscopy result, a positive qPCR result, reported no history of antimalarial treatment during the last month, and were followed-up weekly until Day 21 (D21). Control individuals, had a negative malaria microscopy and qPCR result, no history of antimalarial treatment or malaria infections during the last three years, and no history of comorbidities or chronic infections.

Results

From the 2159 individuals screened during PS, data revealed a low but heterogeneous Pv prevalence across the communities (11.4%), where most infections were Asym (66.7%) and submicroscopic (82.9%). A total of 29 Asym, 49 Sym, and 30 control individuals participated in the nested case - control study (n=78). Ten of the individuals that were initially Asym at D0, experienced malaria symptoms during follow up and therefore, were included in the Sym group. 29 individuals remained Asym throughout all follow-ups. High levels of eosinophils were found in Asym individuals in comparison to Sym and controls.

Conclusion

For the first-time, key epidemiological, hematological, and biochemical features are reported from Pv Asym infections from the Peruvian Amazon. These results should be considered for the design and reshaping of malaria control measures as the country moves toward malaria elimination.

Tropical parasitic itch in returned travellers and immigrants from endemic areas

Itch is the most common skin symptom among tropical parasitic diseases (TPD), but there are limited data about its characteristics in these conditions. In dermatology practices and travellers' health clinics in the developed world, itch is a common complaint among travellers returning from endemic areas, as well among migrants arriving from endemic areas, where they may have been exposed to TPD. Studying aspects of pruritus among TPD may lead to improvements in prompt, accurate diagnosis and management of these conditions. This review examines the major itch-inducing TPDs, including schistosomiasis, echinococcosis, onchocerciasis, scabies, cutaneous larva migrans, larva currens, African trypanosomiasis, dracunculiasis and other causes of travel associated pruritus. We focus on the link between pruritus and other symptoms, aetiology, clinical staging and therapeutic options for these parasitic illnesses. Because some tropical parasitic diseases can present with significant pruritus, we attempt to identify aspects of the pruritus that are characteristic of-or unique to-specific conditions. These diagnostic insights may help clinicians create a rational and focused differential diagnosis and help determine optimal disease management pathways. In this sense, management involves treating the individual, seeking epidemiologically linked cases, preventing recurrences or relapses, and reducing spread of the disease.

Peripheral blood eosinophilia in dogs: Prevalence and associated diseases

BACKGROUND

Canine eosinophilia has not been evaluated over the last two decades. As in human local differences, changes in the prevalence and associated diseases over time can be expected.

OBJECTIVE

This study aims to determine the prevalence and causes of marked blood eosinophilia in dogs.

METHODS

Retrospective study. A total of 317 clinical histories of dogs with an eosinophil concentration > 1.5 × 109 /L (marked eosinophilia) between 2013 and 2017 were evaluated. Patients were allocated to 10 groups according to their major clinical findings.

RESULTS

Eosinophilia was present in 1,592 of 10,829 dogs (14.7%); it was mild (0.8-1.49 × 109 /L) in 78.4%, moderate (1.5 - 4.9 × 109 /L) in 20.5% and severe (> 5 × 109 /L) in 1.1% of cases. Rottweilers were overrepresented (16.1%). Of 317 cases with marked eosinophilia, 19.6% had neoplasia, 19.1% gastrointestinal disorders, 13.6% health check, 10.4% endoparasites, 6% respiratory, 5.4% neurologic, 5.4% dermatologic, 4.8% urogenital, 3.2% endocrine disorders and 12.6% miscellaneous. Lymphomas (29%) and mast cell tumours (12.9%) were the most frequent tumours in the neoplasia group. A total of 72.6% of tumour-bearing dogs were older than 8 years, while 63.6% of dogs had endoparasites, and 86% of apparently healthy dogs were younger than 5 years. Eosinophilia was significantly higher in patients with respiratory disorders (p < 0.0146). Leukocytosis was found in 50.2% of cases.

CONCLUSION

Malignancy was the most common cause of marked blood eosinophilia in older dogs and endoparasitism in younger dogs. Eosinophilia was common in apparently healthy young dogs and may be related to undiagnosed parasitic infestations.

Seroprevalence of anti-Toxocara canis antibodies and associated risk factors among dog owners in the rural community of Nakhon Si Thammarat province, southern Thailand

Background

Human toxocariasis is a zoonotic parasitic disease caused by the Toxocara canis and T. cati nematodes larvae. Dog owners are at a higher risk of acquiring T. canis infection, and there is no available evidence regarding the seroprevalence of T. canis infection among dog owners in Thailand. Therefore, this study aimed to investigate the seroprevalence of T. canis infection and associated risk factors among dog owners in rural areas of Thailand.

Methods

A total of 132 dog owners, including 25 men and 107 women, were recruited for this study. Serum anti-T. canis IgG antibodies were detected using a commercial enzyme-linked immunosorbent assay (ELISA) kit, and information on risk factors was collected using a questionnaire. In addition, hematological parameters were analyzed by the auto hematology analyzer. Risk variables associated with T. canis infection were investigated using univariate and multivariate logistic regression models.

Results

The overall seroprevalence of T. canis was 76.5% (101/132). Men were more likely to be infected with T. canis than women. Univariate analysis revealed that dog owners who did not practice handwashing before meals (p = 0.005) or after contact with soil (p = 0.035) or dogs (p = 0.049) had a substantially higher risk of acquiring T. canis infection. After adjusting for confounders, not practicing handwashing before meals remained a significant risk factor for T. canis infection (p = 0.038). The mean number of eosinophils was significantly higher in the seropositive group than in the seronegative group.

Conclusions

This is the first serological report of T. canis infection among dog owners reflecting the high rate of T. canis seropositivity in rural areas of southern Thailand. This study also provides group-specific data concerning modifiable risk behaviors for more effective T. canis infection control and prevention strategies in Thailand.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41182-022-00425-4.

The regulatory role of eosinophils in viral, bacterial, and fungal infections

Eosinophils are innate immune cells typically associated with allergic and parasitic diseases. However, in recent years, eosinophils have also been ascribed a role in keeping homeostasis and in fighting several infectious diseases. Indeed, these cells circulate as mature cells in the blood and can be quickly recruited to the infected tissue. Moreover, eosinophils have all the necessary cellular equipment such as pattern recognition receptors (PRRs), pro-inflammatory cytokines, anti-bacterial proteins, and DNA traps to fight pathogens and promote an efficient immune response. This review summarizes some of the updated information on the role of eosinophils' direct and indirect mediated interactions with pathogens.

Cross-Sectional Assessment of the Association of Eosinophilia with Intestinal Parasitic Infection in U.S.-Bound Refugees in Thailand: Prevalent, Age Dependent, but of Limited Clinical Utility

The most common causes of eosinophilia globally are helminth parasites. Refugees from high endemic areas are at increased risk of infection compared with the general U.S. population. It is widely accepted that eosinophilia is a good marker for helminth infection in this population, yet its absence has little predictive value for excluding infection. During an enhanced premigration health program, the CDC offered voluntary testing and management of intestinal parasites, among other conditions, to U.S.-bound refugees in Thailand. Stool specimens were tested for Ascaris lumbricoides, Strongyloides stercoralis, Trichuris trichiura, hookworms, Giardia lamblia, Cryptosporidium spp., and Entamoeba histolytica using quantitative polymerase chain reaction. Complete blood counts were performed to identify eosinophilia. Predictive values of eosinophilia for parasitic infections were calculated within nematode groups. Between July 9, 2012 and November 29, 2013, 2,004 participants were enrolled. About 73% were infected with at least one parasite. The overall median eosinophil count was 483 cells/μL (interquartile range [IQR] = 235-876 cells/μL). Compared with participants who did not test positive for any infection, higher eosinophil counts were observed in those infected with A. lumbricoides (RR = 1.3, 95% CI = 1.1-1.4), S. stercoralis (RR = 1.8, 95% CI = 1.4-2.4), Necator americanus (RR = 1.2, 95% CI = 1.1-1.4), and Ancylostoma ceylanicum (RR = 1.8, 95% CI = 1.5-2.2). Eosinophil counts were higher in younger participants (2-4 years versus 65+ years: RR = 4.2, 95% CI = 2.5-6.9), and lower in female participants (RR = 0.9, 95% CI = 0.8-0.9). Sensitivities ranged from 51% to 73%, specificities from 48% to 65%, and predictive values from 4% to 98%. The predictive value of eosinophilia is poor for the most common parasitic infections, and it should not be used alone for screening refugees.

Eosinophilia in Migrant Children: How Should We Proceed?

BACKGROUND

The diagnostic approach to eosinophilia is complex, given the numerous reported etiologies. Intestinal parasites (especially helminths) are a concern in children from high-burden settings. We describe the diagnostic approach and clinical management of eosinophilia in a cohort of migrant children.

METHODS

We conducted a retrospective observational study that included children diagnosed with eosinophilia at a reference center for pediatric tropical diseases from 2014 to 2018. All patients were screened according to a unified protocol, including direct microbiologic and serologic tests.

RESULTS

A total of 163 children presented with eosinophilia during the study period [median age, 7.7 years (4.1-12.2); 57.1% boys], mostly from Asia (27.6%) and South America (22.1%). Most were internationally adopted children (43.6%) or migrants (26.4%). Only 34.4% of the children were symptomatic, and the main etiology for eosinophilia was helminths (56.4%). After a sequential diagnostic approach, no etiology was found for 40.5% of the patients. The independent risk factors for an unexplained etiology were younger age (≤2 years: odds ratio, 3.6; 95% CI, 1.3-10.2; P = 0.015), absence of symptoms (odds ratio, 4.8; 95% CI, 1.8-12.5; P = 0.001) and mild eosinophilia (<1000/µL: odds ratio, 4.2; 95% CI, 4.5-11.7; P = 0.005). Only 6 children were treated empirically. In those children with an identified cause and in those treated empirically, the eosinophilia resolved in 52% in a median of 7 months (5-9).

CONCLUSIONS

Helminths are the main cause of eosinophilia in migrant children and need to be hunted, especially in older children with eosinophil counts >1000 eosinophils/µL.

Pregnant lady with eosinophilia: common cause, uncommon association

Peripheral eosinophilia can have a myriad of causes and presents a diagnostic challenge in everyday practice. Tropical pulmonary eosinophilia (TPE), seen commonly in tropics, is an immunological reaction to filarial parasites. This disease can present with clinical features that closely mimic asthma, eosinophilic pneumonia, and Loffler's syndrome. Differentiating between these diseases is essential owing to marked differences in treatment. This can be further challenging in pregnancy as any wrong treatment is likely to affect both the mother and the child. We report a case of a pregnant lady who presented with eosinophilia and of how she was worked up to the correct diagnosis. There are only few reported cases of TPE in pregnancy, and there are no reported cases from India. The case also underlines the approach required in these patients to reach the correct diagnosis.

Typhoid Fever and Helminth Coinfection: A Pediatric Case Report

Enteric fever and helminth infestation coinfection is commonly seen among children below the age of 5, living in areas with poor sanitation in Africa. These can be explained due to the fact that both enteric fever and ascariasis, are contracted via fecal-oral routes. Although the immune system of children is presumed to be stronger and capable of eliminating several infectious agents, it is not applicable to children below the age of 5. Balanced nutrition also plays a vital role in sustaining strong immunity in children of all age groups and so, it could be one of the contributing factors to high susceptibility to co-infectious diseases among children living in poor countries. Soil-transmitted helminths (STH) are very common in developing countries. They are caused by infection with roundworm, hookworm, or whipworm. Both typhoid fever and helminth infestation in children presents with almost similar clinical symptoms. We present a case of coinfection with typhoid fever caused by Salmonella typhi bacteria and helminth in a 4-year-old child from Nigeria.

Latent Strongyloides stercoralis in an Asymptomatic Male With Chronic Peripheral Eosinophilia

Peripheral eosinophilia is a potentially concerning finding that can occur due to a multitude of causes. One such cause is latent helminth infections such as Strongyloides stercoralis. These parasites have broad distributions throughout the developing world, particularly South and Southeast Asia and it is estimated that roughly 200 million people have latent infections. We present the case of a 74-year-old patient from India who had asymptomatic eosinophilia since before 2006. He previously underwent an extensive workup which included testing for neoplasms, gene mutations, and lymphoproliferative disorders. After carefully examining the patient's travel history and demographic information, a parasite panel was administered which was positive for Strongyloides, thereby establishing a cause for his condition after years of expensive testing. Latent Strongyloides infections can lead to fatal dissemination if the host becomes immunocompromised. It is therefore essential to keep a detailed history of patient travel, occupation, and functional status when assessing peripheral eosinophilia so that obvious causes are not overlooked.

Reduction/elimination of blood eosinophils in severe asthma: should there be a safety consideration?

INTRODUCTION

Eosinophils play a central role in the inflammation of asthma and are the target of new biologic treatments for patients with severe asthma. Biologics targeting the IL-5 pathway have been shown to reduce asthma exacerbations, improve lung function, reduce oral corticosteroid use, and improve quality of life, accompanied by reduced or even eliminated blood eosinophils. Eosinophils have been associated with host protection and tumor growth, raising potential concerns about the consequences of these long-term therapies that reduce or eliminate them.

AREAS COVERED

In this review, we explore the current safety profile of biologics regarding the impact they may have on blood eosinophils, trying to answer the question about any safety consideration.

EXPERT OPINION

Eosinophils have been associated with host protection and tumor growth, raising potential concerns about the consequences of long-term therapies that reduce or eliminate these blood cells.

The kinetic profile of clinical and laboratory findings and treatment outcome of patients with toxocariasis

OBJECTIVES

Human toxocariasis is a widespread zoonosis for which a chemotherapy decision and therapy effectiveness are difficult to determine. We aimed to investigate the kinetic profile of clinical and laboratory findings and treatment outcome of patients with toxocariasis in Vietnam.

METHODS

The prospective study was conducted between October 2017 and June 2019. The diagnosis of toxocariasis was established based on clinical, laboratory (eosinophilia, raised IgE concentration) and serological (positive Toxocara IgG ELISA) evaluation as well as the exclusion of another helminthic co-infection. The patients were followed up after seven days, then one, three and six months after chemotherapy by thiabendazole.

RESULTS

The study involved 80 patients with a mean age of 41.6 ± 15.2 years of whom 58.8% were female. At three and six months after chemotherapy, most patients demonstrated resolution of clinical signs and symptoms, eosinophil count and IgE concentration but not in the proportion of IgG seropositivity. Skin lesions and eosinophilia resolved earlier than the other symptoms (one month after treatment). About four-fifths of the patients were "cured" after three and six months of follow-up; 33.8% showed side effects to thiabendazole therapy but no severe events were reported. The most common adverse reaction was neurologic symptoms followed by gastrointestinal or skin manifestations which lasted as long as 4 days.

CONCLUSIONS

In toxocariasis patients, cutaneous manifestations and eosinophilia resolve more rapidly than other clinical and laboratory findings while IgG titre has a very slow kinetic after therapy. Thiabendazole seems to be a potential alternative for the treatment of human toxocariasis.

Case Report: Diagnosis and Assessment of Cure Approaches for Acute Schistosomiasis in Pre-School Children

Acute schistosomiasis (AS) manifests with a broad spectrum of clinical features in pediatric populations. Diagnosis may be difficult in the absence of detectable numbers of eggs. As a result, new approaches may be required to achieve an accurate diagnosis. Optimal praziquantel (PZQ) treatment regimen for young children is debatable. Also, the post-treatment response is still poorly evaluated due to the lack of reliable markers. A group of 6 children (a toddler and 5 pre-school children) and one pre-adolescent were investigated for AS clinical manifestations and followed-up for two years after treatment. Ova detection was performed by Kato-Katz (KK) and presence of Schistosoma mansoni DNA was assessed by real-time PCR (rt-PCR) in stool samples. IgG and IgE anti-Schistosoma levels and urinary antigen were detected by ELISA and point-of-care circulating cathodic antigen (POC-CCA) testing in serum and urine, respectively. AS clinical symptoms were present in 5/7 (71.4%) of the infected children, and hypereosinophilia was detected in all of them. Ova detection and serology were positive in only 3/7 (44.9%) and 4/7 (57.1%), respectively. However, real-time PCR (rt-PCR) showed the presence of Schistosoma DNA in 6/7 (85.7%) of the cases, and urinary antigen was detected in all infected children. The long-term follow-up after treatment with three doses of PZQ (80mg/kg/dose), showed high cure rates (CR) as demonstrated by the DNA-based assay as well as reduced levels of side effects. CR based on urinary antigen detection ranged from 28.6 to 100%, being the highest CR due to double testing the 2-year post-treatment samples. The results suggest that high dose and repeated treatment with PZQ might be effective for AS in young children. Also, new laboratory markers should be considered to diagnosis and monitor the drug response.

Role of Short Chain Fatty Acids and Apolipoproteins in the Regulation of Eosinophilia-Associated Diseases

Eosinophils are key components of our host defense and potent effectors in allergic and inflammatory diseases. Once recruited to the inflammatory site, eosinophils release their cytotoxic granule proteins as well as cytokines and lipid mediators, contributing to parasite clearance but also to exacerbation of inflammation and tissue damage. However, eosinophils have recently been shown to play an important homeostatic role in different tissues under steady state. Despite the tremendous progress in the treatment of eosinophilic disorders with the implementation of biologics, there is an unmet need for novel therapies that specifically target the cytotoxic effector functions of eosinophils without completely depleting this multifunctional immune cell type. Recent studies have uncovered several endogenous molecules that decrease eosinophil migration and activation. These include short chain fatty acids (SCFAs) such as butyrate, which are produced in large quantities in the gastrointestinal tract by commensal bacteria and enter the systemic circulation. In addition, high-density lipoprotein-associated anti-inflammatory apolipoproteins have recently been shown to attenuate eosinophil migration and activation. Here, we focus on the anti-pathogenic properties of SCFAs and apolipoproteins on eosinophil effector function and provide insights into the potential use of SCFAs and apolipoproteins (and their mimetics) as effective agents to combat eosinophilic inflammation.

Extensive pulmonary artery embolisation caused by cardiac hydatid cyst rupture

This case study is a rare example of cardiac hydatidosis in a high-income country, where a middle-aged man presented with a ruptured right ventricular cyst causing anaphylaxis, pulmonary emboli and dissemination of Echinococcus throughout the lung. He survived the cyst rupture and underwent cardiac surgery but had incomplete resection and experienced progressive cardiopulmonary hydatidosis despite antihelminthic therapy. As a result, he experienced an array of cardiopulmonary sequelae over his lifespan. This case report highlights rare clinical manifestations of hydatid disease and potential complications of its treatment.

Episodic Angioedema with Hypereosinophilia (Gleich's Syndrome): A Case Report and Extensive Review of the Literature

Episodic angioedema with eosinophilia (EAE) (Gleich's syndrome) is a rare disease characterized by hypereosinophilia (up to 95 × 10⁹ cells/L), recurrent episodes of angioedema, urticaria, weight gain, and fever, that occur at periodical intervals (usually every 3-4 weeks). The exact etiology of EAE is still unclear, but both eosinophils and abnormalities of cytokines homeostasis seem to play a pivotal role in the pathogenesis of the disease. In particular, the cyclic elevation of serum interleukin-5 before the increase in eosinophil count has been reported. Herein, we performed a broad literature review and report the case of a thirty-two-year-old woman with a two-year history of cyclic angioedema attacks, urticaria, periodic weight gain, and severe hypereosinophilia, diagnosed with EAE and treated with oral corticosteroids. Describing the most relevant clinical features of EAE reported so far in the literature, we aim to provide physicians with some useful tools to help them deal with this disease. In addition, we aim to raise awareness about this rare condition in which approved diagnostic classification criteria are currently missing.

Hypereosinophilic syndromes - An enigmatic group of disorders with an intriguing clinical spectrum and challenging treatment

Hypereosinophilic syndromes (HES) comprises a group of rare disorders characterized by blood hypereosinophilia (>1.5 × 10⁹/l) accompanied by eosinophil-associated organ damage. The 2016 World Health Organization classification recognizes a category of myeloid/lymphoid neoplasms with prominent eosinophilia (M/L_eo) and well-characterized gene rearrangements of PDGFRA/B, FGFR1 or JAK2. PDGFRA/B-rearranged patients usually manifest as imatinib-sensitive myeloproliferative neoplasms (MPNs). FGFR1- and JAK2- rearranged cases may manifest as MPNs or aggressive lymphomas/leukemias and historically have had a dismal prognosis, although clinical trials with targeted treatment are promising. A negative screen for M/L_eo in a patient with myeloid features should prompt consideration of a diagnosis of chronic eosinophilic leukemia-not otherwise specified. If these are excluded and a secondary cause is not identified, a diagnosis of idiopathic HES and/or other rare variants of HES should be considered. This review, through an illustrative case, summarizes current knowledge on HES pointing at new directions in diagnosis and treatment.

Recent Advances in Camel Immunology

Camels are domesticated animals that are highly adapted to the extreme desert ecosystem with relatively higher resistance to a wide range of pathogens compared to many other species from the same geographical region. Recently, there has been increased interest in the field of camel immunology. As the progress in the analysis of camel immunoglobulins has previously been covered in many recent reviews, this review intends to summarize published findings related to camel cellular immunology with a focus on the phenotype and functionality of camel leukocyte subpopulations. The review also describes the impact of different physiological (age and pregnancy) and pathological (e.g. infection) conditions on camel immune cells. Despite the progress achieved in the field of camel immunology, there are gaps in our complete understanding of the camel immune system. Questions remain regarding innate recognition mechanisms, the functional characterization of antigen-presenting cells, and the characterization of camel NK and cytotoxic T cells.

Anterior chamber granuloma: conservative treatment versus surgical intervention

PURPOSE

A distinct pattern of granulomatous anterior uveitis, with white anterior chamber (AC) granuloma, has been reported in certain endemic areas. The aim of this work was to compare the outcome of conservative treatment to surgical intervention for the treatment of large AC granulomas presenting with moderate-severe anterior uveitis. The secondary outcome is ultrasound biomicroscopy (UBM) characterization of AC granulomas.

METHODS

This is a prospective randomized interventional study including 41 eyes of 39 patients with active AC granuloma ≥3 mm (flare & cells ≥ +2). Patients were randomly assigned to either conservative treatment in the form of topical prednisolone and cycloplegic drops with orbital floor (transseptal) injection of Triamcinolone acetonide (20 eyes) or surgery in the form of granuloma excision and AC wash (21 eyes). As a perioperative care, topical steroids and cycloplegic drops were given few days before surgery and tapered gradually over 6 weeks. Patients were followed up at first day, 2 weeks, 1 and 3 months.

RESULTS

Thirty-seven patients were males, and 2 were females (13.0 ± 3.5 years). After 2 weeks, disappearance/healing of granuloma was achieved in 20 eyes in the surgical group versus 2 eyes in the conservative group (p < 0.0001). This effect was maintained throughout the follow-up period, for the surgical group and reached up to 70%, for the medical group. At every follow-up, BCVA was better in the surgical group, but this was only statistically significant at 1 and 3 months. The granuloma appeared as a homogenous hyperreflective lesion in examined eyes (16 eyes of 15 patients).

CONCLUSION

Surgical treatment of large granulomas leads to a more complete and rapid resolution of inflammation.

Eosinopenia as predictor of infection in patients admitted to an internal medicine ward: a cross-sectional study

Supplemental Digital Content is available in the text

Background:

The identification of infection in an internal medicine ward is crucial but not always straightforward. Eosinopenia has been proposed as a marker of infection, but specific cutoffs for prediction are not established yet. We aim to assess whether there is difference in eosinophil count between infected and noninfected patients and, if so, the best cutoffs to differentiate them.

Methods:

Cross-sectional, observational study with analysis of all patients admitted to an Internal Medicine Department during 2 consecutive months. Clinical, laboratory and imaging data were analyzed. Infection at hospital admission was defined in the presence of either a microbiological isolation or suggestive clinical, laboratory, and/or imaging findings. Use of antibiotics in the 8 days before hospital admission, presence of immunosuppression, hematologic neoplasms, parasite, or fungal infections were exclusion criteria. In case of multiple hospital admissions, only the first admission was considered.

Sensitivity and specificity values for eosinophils, leukocytes, neutrophils, and C-reactive protein were determined by receiver operating characteristic curve. Statistical analysis was performed with IBM SPSS Statistics® v25 and MedCalc Statistical Software® v19.2.3.

Results:

A total of 323 hospitalization episodes were evaluated, each corresponding to a different patient. One hundred fifteen patients were excluded. A total of 208 patients were included, 62.0% (n = 129) of them infected at admission. Ten patients had multiple infections.

Infected patients had fewer eosinophils than uninfected patients (15.8 ± 42 vs 71.1 ± 159 cell/mm³; P < .001). An eosinophil count at admission ≤69 cell/mm³ had a sensitivity of 89.1% and specificity of 54.4% (area under the curve 0.752; 95% confidence interval 0.682–0.822) for the presence of infection. Eosinophil count of >77 cells/mm³ had a negative likelihood ratio of 0.16.

Conclusions:

Eosinophil count was significantly lower in infected than in uninfected patients. The cutoff 69 cells/mm³ was the most accurate in predicting infection. Eosinophil count >77 cells/mm³ was a good predictor of absence of infection.

The immunoglobulin G antibody response to malaria merozoite antigens in asymptomatic children co-infected with malaria and intestinal parasites

Background

Co-infection with malaria and intestinal parasites is common in children in Africa and may affect their immune response to a malaria parasite infection. Prior studies suggest that co-infections may lead to increased susceptibility to malaria infection and disease severity; however, other studies have shown the reverse. Knowledge on how co-morbidities specifically affect the immune response to malaria antigens is limited. Therefore, this study sought to determine the prevalence of co-infection of malaria and intestinal parasites and its association with antibody levels to malaria merozoite antigens.

Methods

A cross sectional study was carried out in two villages with high transmission of malaria in Cameroon (Ngali II and Mfou) where mass drug administration (MDA) had been administered at ~6-month intervals (generally with albendazole or mebendazole). Children aged 1–15 years were enrolled after obtaining parental consent. A malaria rapid diagnostic test was used on site. Four (4) ml of peripheral blood was collected from each participant to determine Plasmodium falciparum infections by microscopy, haemoglobin levels and serology. Fresh stool samples were collected and examined by wet mount, Kato-Katz method and modified Ritchie concentration techniques. A Multiplex Analyte Platform assay was used to measure antibody levels.

Results

A total of 320 children were enrolled. The prevalence of malaria by blood smear was 76.3% (244/320) and prevalence of malaria and intestinal parasites was 16.9% (54/320). Malaria prevalence was highest in young children; whereas, intestinal parasites (IP+) were not present until after 3 years of age. All children positive for malaria had antibodies to MSP1₄₂, MSP2, MSP3 and EBA175. No difference in antibody levels in children with malaria-co infections compared to malaria alone were found, except for antibody levels to EBA-175 were higher in children co-infected with intestinal protozoa (p = 0.018), especially those with Entamoeba histolytica infections (p = 0.0026).

Conclusion

Antibody levels to EBA175 were significantly higher in children co-infected with malaria and E. histolytica compared to children infected with malaria alone. It is important to further investigate why and how the presence of these protozoans might modulate the immune response to malaria antigens.

Acute kidney injury associated with intestinal infection by Cyclospora cayetanensis in a kidney transplant patient. A case report

This study shows a clinical case report of a kidney transplant patient who traveled from Mexico to The Netherlands and ate green vegetables in an international food restaurant. After 5 days, he started having diarrhea, nausea, colic, and a physical feeling of malaise. The patient only received symptomatic treatment after showing the characteristic symptoms of traveler's diarrhea. When he returned to Mexico, the clinical picture worsened, and he was hospitalized. Clinical analyses indicated dehydration and acute kidney injury stage II. Coproparasitoscopic study showed the presence of Cyclospora cayetanensis. Parenteral solutions, gastric mucosal protector, ciprofloxacin, and a soft diet were administrated as treatment. The patient was discharged 72 h later with an improvement of the kidney function.

Educational Case: Hematologic and Immunologic Response to Allergic Rhinitis With Other Causes of Leukocytosis

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, seehttp://journals.sagepub.com/doi/10.1177/2374289517715040.¹

Approach to Eosinophilia Presenting With Pulmonary Symptoms

Eosinophilia with pulmonary involvement is characterized by the presence of peripheral blood eosinophilia, typically ≥500 cells/mm³, by pulmonary symptoms and physical examination findings that are nonspecific, and by radiographic evidence of pulmonary disease and is further supported by histopathologic evidence of tissue eosinophilia in a lung or pleura biopsy specimen and/or increased eosinophils in BAL fluid, usually >10%. Considering that there are a variety of underlying causes of eosinophilia with pulmonary manifestations and overlapping clinical, laboratory, and radiologic features, it is essential to approach the evaluation of eosinophilia with pulmonary findings systematically. In this review, we will describe a case presentation and discuss the differential diagnosis, a directed approach to the diagnostic evaluation and supporting literature, the current treatment strategies for pulmonary eosinophilia syndromes, and the levels of evidence underlying the recommendations, where available. Overall, optimal management of eosinophilic lung disease presentations are directed at the underlying cause when identifiable, and the urgency of treatment may be guided by the presence of severe end-organ involvement or life-threatening complications. When an underlying cause is not easily attributable, management of eosinophilia with pulmonary involvement largely relies on eosinophil-directed interventions, for which biologic therapies are increasingly being used.