Parasitological transitions: selected outcomes from the XXXII Congress of the Italian Society for Parasitology.

Founded in 1959, the Italian Society of Parasitology (SoIPa) includes nearly 200 researchers and professionals in the fields of medicine, veterinary medicine, biotechnology, epidemiology and environmental sciences. The diversity of its members, in a historical and continuous collaboration with other international scientific societies, embodies a broad and multidisciplinary field such as parasitology. Since 1959, SoIPa has organized a biennial congress, covering all aspects of general parasitology with participants from all over Italy, Europe and beyond, involved in a dynamic and multi-faceted scientific framework of contributions and symposia. The present Special Issue (SI) contains 6 review papers and 1 research article, focussed on emerging topics presented and discussed during some of the symposia organized within the XXXII SoIPa Congress, held in Naples from 27th June to 30th June 2022. These review papers reflect several emerging subjects (i.e. 'Italian network on Neglected Tropical Diseases', 'Wildlife parasites and citizen science', 'Comparing approaches to parasitological issues', 'Unusual perspectives on the role of parasites') with the aim to explore the new role that parasitologists can play in the future society, working together to promote dialogue on science-informed decisions to support the so-called 'twin green and digital transition'.

Angiostrongyliasis: A Changing Scenario?

Angiostrongyliasis is a parasitic disease caused by larvae of the genus Angiostrongylus, with Angiostrongylus cantonensis and Angiostrongylus costaricensis being the two main species causing diseases in humans [...].

An Unexpected Case of Opisthorchis felineus Infection Revealed during Liver Transplantation.

A man with hepatitis B infection was admitted to Pisa University Hospital for hepatological evaluation, which revealed multiple cystic lesions and suggested a cirrhotic evolution. Treatment with Entecavir 0.5 mg/day was started, resulting in rapid viral load suppression and alanine aminotransferase normalization. After 10 years, imaging documented a single nodule of hepatocellular carcinoma (HCC), and a robot-assisted nodule resection was performed. One year later, HCC recurrence prompted orthotopic liver transplantation, during which the patient died because of the sudden rupture of the donor's organ and rapid multiorgan deterioration before retransplantation. During post-mortem liver examination, adult worms were evidenced within large biliary ducts, suggesting infection with Opisthorchis or Clonorchis spp. flukes. Sequencing of the ITS2 locus, following PCR amplification of DNA extracted from liver tissue, revealed 100% identity with the reference sequence of O. felineus. Infection of the patient with O. felineus was confirmed by the presence of specific IgG detected by ELISA in the patient's sera. Two major alkaline phosphatase serum levels peaks observed during the first two years of antiviral therapy support the hypothesis that O. felineus infection worsened liver function. This case report highlights the importance of a very careful screening of parasitic infections in solid organ transplantation candidates.

Neglected Tropical Diseases in Italy: introducing IN-NTD, the Italian network for NTDs.

The World Health Organization (WHO) defines neglected tropical diseases (NTDs) as a diverse group of primarily infectious diseases, which disproportionately affect poor and marginalized populations worldwide. In this context, NTDs are responsible for important morbidity and mortality and justify a global response. Moreover, NTDs are relatively neglected by research and development as well as by funding, if compared with the magnitude of the public health problem they represent. This happens even though, unlike other infectious diseases, they can be prevented, controlled and eliminated by targeted public health interventions. NTDs are mainly prevalent in communities from low-income countries in tropical and sub-tropical areas but are also present in upper­middle-income countries, including several in Europe. Here, we provide an update on the most relevant parasitic endemic or imported NTDs in Italy and illustrate the rationale for the establishment of the Italian network on NTDs, an alliance of scientific societies, institutes, foundations, universities and non-profit organizations united to fight NTDs.

Eosinophilia and potential antibody cross-reactivity between parasites in a child with pinworm and immune dysregulation: a case report.

BACKGROUND: Intestinal parasitic infections are common in humans, especially among young children. These conditions are often asymptomatic and self-limiting, and diagnosis is mainly based on the search for ova and parasites in the stools since serology may be biased due to cross reactivity between parasites. Pinworm is common in children and is not usually associated with hypereosinophilia; adhesive-tape test is the gold standard testing for the microscopic detection of Enterobious vermicularis (Ev) eggs. CASE PRESENTATION: A 13-year-old boy was referred due to a self-resolving episode of vomiting and palpebral oedema after dinner, together with a history of chronic rhinitis, chronic cough, absolute IgA deficiency and Hashimoto's thyroiditis and hypereosinophilia (higher value = 3140/µl). On evaluation we detected only palpable thyroid and hypertrophic nasal turbinates. Food allergy was excluded, but skin prick tests showed sensitization to house dust mites and cat epithelium and spirometry showed a marked obstructive pattern with positive bronchodilation test prompting the diagnosis of asthma for which maintenance inhaled treatment was started. Chest x-ray and abdomen ultrasound were negative. Further blood testing showed positive IgG anti-Echinococcus spp. and Strongyloides stercoralis and positive IgE for Ascaris, while Ev were detected both by the adhesive tape test and stool examination, so that we made a final diagnosis of pinworm infection. Three months after adequate treatment with pyrantel pamoate the adhesive-tape test turned out negative and blood testing showed a normal eosinophil count. The child later developed also type 1 diabetes. CONCLUSIONS: We suggest the need to investigate for enterobiasis in children with hypereosinophilia and to consider autoimmunity as a potential confounding factor when interpreting serology for helminths.

Increased neutrophil derived chemokines (CXCL10 and CCL2) in human trichinellosis as possible serological markers of the polarization of the immune response against the parasite.

Trichinella britovi is a widely distributed parasitic nematode, transmitted through ingestion of raw or poorly cooked meat containing muscle larvae. This helminth can regulate the host immune system during the early phase of infection. The immune mechanism mainly involves the interaction of Th1 and Th2 responses and related cytokines. Chemokines (C-X-C or C-C) and matrix metalloproteinases (MMPs) have also shown to be implicated in a number of parasitic infections, mainly malaria, neurocysticercosis, angiostronyloidosis, and schistosomiasis, but poor is known about their role in human Trichinella infection. We previously found that serum MMP-9 levels were significantly increased in T. britovi infected patients with relevant symptoms such as diarrhea, myalgia, and facial oedema, which makes these enzymes a potential reliable indicator of inflammation in trichinellosis patients. These changes were also observed in T. spiralis/T. pseudospiralis experimentally infected mice. No data are available about circulating levels of two pro-inflammatory chemokines, CXCL10 and CCL2, in trichinellosis patients with or w/o clinical signs of the infection. In this study, the association of serum level of CXCL10 and CCL2 with clinical outcome of T. britovi infection and their relation to MMP-9 were investigated. Patients (median age 49 ± 0.33 years) acquired infection by consuming raw sausages prepared with wild boar and pork meat. Sera were collected during the acute and the convalescent phases of the infection. A positive significant association (r = 0.61, p = 0.0004) was observed between MMP-9 and CXCL10 levels. The CXCL10 level significantly correlated with the severity of symptoms in patients being particularly higher in patients suffering diarrhea, myalgia, and facial oedema, thus suggesting a positive association of this chemokine with symptomatologic traits, especially myalgia (and increased LDH and CPK levels) (p < 0.005). No correlation was found between levels of CCL2 and the clinical symptoms.

Artesunate and dihydroartemisinin-piperaquine treatment failure in a severe Plasmodium falciparum malaria case imported from Republic of Côte d'Ivoire.

A 68-year-old man returning from Republic of Côte d'Ivoire (Ivory Coast) was diagnosed with severe Plasmodium falciparum malaria and treated with intravenous artesunate followed by oral dihydroartemisinin-piperaquine (DHA-PPQ). A month later the patient experienced a new P. falciparum episode; analysis of pfmsp-1 and pfmsp-2 revealed that the infection was caused by a genetic strain identical to the strain that caused the initial episode, indicating resurgence of the previous infection. No mutations in genes associated with resistance to artemisinin derivatives (pfk13) or piperaquine (pfexonuclease, pfplasmepsin 2/3) were detected, suggesting that treatment failure could have been caused by drug malabsorption or poor drug manufacturing practices. A second treatment with atovaquone-proguanil was successful in eliminating the infection, with no further relapses. To our knowledge, this is the first description of a treatment failure with both artesunate and DHA-PPQ in a traveler returning from a malaria-endemic region. Analysis of molecular markers of resistance to antimalarial drugs revealed mutations associated with resistance to sulfadoxine (pfdhps) and pyrimethamine (pfdhfr), highlighting the important contribution of surveillance of imported malaria cases to the monitoring of drug resistance globally.

Anti-glutathione S-transferase omega 1-1 (GSTO1-1) antibodies are increased during acute and chronic inflammation in humans.

Glutathione S-transferase omega-1 (GSTO1-1) is a cytosolic enzyme involved in the modulation of critical inflammatory pathways as well as in cancer progression. Auto-antibodies against GSTO1-1 were detected in the serum of patients with esophageal squamous cell carcinoma and were proposed as potential biomarkers in the early detection of the disease. Our findings show that anti-GSTO1-1 antibodies can be found in a variety of inflammatory diseases, including autoimmune rheumatoid arthritis, infectious SARS-CoV-2, and trichinellosis. Our findings strongly suggest that anti-GSTO1-1 antibodies may be a marker of tissue damage/inflammation rather than a specific tumor-associated biomarker.

Ocular toxoplasmosis, an overview focusing on clinical aspects.

Toxoplasma gondii is a widespread protozoan parasite infecting approximately one third of the world population. After proliferation of tachyzoites during the acute stage, the parasite forms tissue cysts in various anatomical sites and establishes chronic infection. Nowadays the nature of the interplay between the protozoan and its human host remains elusive. This is clearly evident in ocular toxoplasmosis, in which the parasite establishes an ambivalent relationship with the eye, manipulating the immune response and inducing variable initial lesions and further relapses. This review will focus on epidemiology and environmental, parasite and host related risk factors, clinical manifestations and laboratory findings, treatment and prophylaxis approaches in ocular toxoplasmosis. An image collection of patients referred to the Unit of Ophthalmology of Pisa's Hospital will be presented, too.

Trichinella spiralis excretory-secretory products downregulate MMP-9 in Dark Agouti rats affected by experimental autoimmune encephalomyelitis.

Matrix metalloproteinases (MMPs), are implicated in the pathogenesis of multiple sclerosis (MS) and in its animal model, experimental autoimmune encephalomyelitis (EAE). Our aim was to investigate whether amelioration of EAE in Dark Agouti (DA) rats, induced by Trichinella spiralis muscle larvae excretory-secretory products (ES L1), could be related to the level and activity of gelatinases, MMP-9 and MMP-2. Serum levels of MMP-9, MMP-2, NGAL/MMP-9, TIMP-1, and cytokines, evaluated by gel-zymography or ELISA, as well as gelatinases and TIMP-1 expression in the spinal cord (SC), were determined in: i) EAE induced, ii) ES L1-treated EAE induced animals. Milder clinical signs in ES L1-treated EAE induced DA rats were accompanied with lower serum levels of MMP-9 and NGAL/MMP-9 complex. However, the correlation between the severity of EAE and the level of serum MMP-9 was found only in the peak of the disease, with MMP-9/TIMP-1 ratio higher in EAE animals without ES L1 treatment. Lower expression of MMP-9 in SC of ES L1-treated, EAE induced rats, correlated with the reduced number of SC infiltrating cells. In SC infiltrates, in the effector and the recovery phase, production of anti-inflammatory cytokines IL-4 and IL-10 was higher in animals treated with ES L1 prior to EAE induction, compared to untreated EAE animals. Reduced expression of MMP-9 in SC tissue, which correlated with the reduced number of infiltrating cells, might be ascribed to regulatory mechanisms, among which is IL-10.

Molecular Identification of New Cases of Human Dirofilariosis (Dirofilaria repens) in Italy.

(1) Dirofilariosis is a vector-borne parasitic disease mainly in domestic and wild carnivores caused by Dirofilaria (Noctiella) repens, which is endemic in many countries of the Old World, and D. immitis, which has a worldwide distribution. In recent years, an increase in the number of human cases has been reported, suggesting that dirofilariosis is an emergent zoonosis. Here, we describe further cases (N = 8), observed in Central Italy during the years 2018-2019. (2) Molecular diagnosis was performed on: (i) live worms extracted from ocular conjunctiva, cheek, and calf muscle; (ii) histological sections of surgically removed nodules from parenchymal lung, coccyx, and breast. (3) Sequence analysis (650-bp) of the mitochondrial cytochrome oxidase subunit I gene (mtDNA cox1) showed a match of 100% with the sequences of D. repens previously deposited in GenBank. ELISA test to detect IgG against filarial antigens was performed on four patients' sera and resulted positive in two patients who showed ocular and subcutaneous dirofilariosis, respectively. Microfilariae have been never detected in the peripheral blood of the patients. (4) The occurrence of N = 8 new cases of human D. repens-infections observed in a two-year period suggests an increased circulation of the parasite in Italy. Therefore, dirofilariosis should be included in differential diagnosis in patients presenting subcutaneous and/or pulmonary nodules. Molecular diagnosis of the etiological agents is fundamental. Specific serological diagnosis needs to be improved in future research work.

In Vivo Eosinophil Expansion Using Gene Transfer by Electroporation.

Eosinophils are differentiated in the bone marrow and transit through the blood circulation to home into tissues primarily under the regulation of IL-5. Because the number of eosinophils in the peripheral blood is relatively low under normal conditions, in vivo functional studies of eosinophils remain extremely difficult. Increasing their numbers in vivo might be useful for assessing eosinophil activities during parasite infections, allergic inflammation, and so on. Here, we provide a method for eosinophil expansion using IL-5 gene transfer by electroporation in vivo.

Toxocariasis in a Child with Autism Spectrum Disorder.

A boy affected by autism spectrum disorder was admitted for persistent high fever, without shiver, for two weeks. The boy referred to abdominal pain, in the first week of fever, and to mild anorexia in the last days before admittance to our hospital centre. The father reported that the boy suffered by geophagia and coprophagia and he has been going to a didactical farm (where he has been exposed to several kinds of animals) to improve his neuropsychiatric condition. Blood analysis shows severe eosinophilia and high levels of total IgE, and abdominal echocardiography showed hepatic lesions. Enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) confirmed the suspicion of toxocariasis, linked to the habit of the boy to ingest ground or animal faeces in a didactic farm frequented by the boy. Treatment with albendazole and prednisone was administered with a rapid improvement of the symptoms and the laboratory findings and significant reduction of the hepatic lesion.

Glutathione-S-transferase omega 1 and nurse cell formation during experimental Trichinella infection.

The glutathione-S-transferases omega (GSTO) are multifunctional enzymes involved in cellular defense. During the nurse cell (NC) formation in Trichinella spiralis infection, the structural and regulatory genes of the skeletal muscle cell are downregulated and a new phenotype is acquired which advances parasite growth and survival. Previous studies showed that the GSTO1 is overexpressed in the NC during T. spiralis infection. To clarify the role of GSTO1 during NC formation, we evaluated the production of this enzyme by immunohistochemistry (IHC) in the diaphragms of mice experimentally infected with T. spiralis at 15, 28 and 60 days post infection (dpi); phosphorylation of Akt (p-Akt) and JNK1 (p-JNK1) were also evaluated. Furthermore, we evaluated the in vitro effects of T. spiralis excretory/secretory (ES) products from muscle larvae on specific functions (viability, proliferative response, apoptosis) in two cell lines (HeLa and U937), as well as its ability to induce GSTO1, p-AkT, p-ERK1/2 and p-JNK1. Results showed that GSTO1 was elevated in NC present in the diaphragms of T. spiralis experimentally infected mice at 15 dpi and progressively increased up to 60 dpi. The activation pattern of Akt in NC was similar to that of GSTO1, whereas JNK1 was never phosphorylated. ES induced a dose-dependent proliferative response in U937 cells, at 24 h and 48 h of treatment, but not in HeLa cells. However, after 72 h following treatment, significant cell death was observed in both cell lines at all doses. The apoptotic index (a.i.) was significantly higher than in untreated cells in both cell lines but only at the highest concentration of ES tested. Furthermore, Western Blots revealed that cells treated with ES for 24, 48 and 72 h, exhibited time-dependent overexpression of GSTO1, whereas p-Akt appeared only after 24 h of treatment. The p-ERK-1/2 peaked at 24 h then declined at 48 h and 72 h after treatment; however, it remained significantly higher than in untreated cells. No changes were observed in p-JNK1 at 24 and 48 h after treatment but a sharp increase in p-JNK1 was observed at 72 h. Also in HeLa cells, ES induced a small but significant increase in GSTO1 expression after 24 and 48 h of treatment where p-JNK1 was present only after 72 h of treatment. In conclusion, T. spiralis ES can reproduce in vitro the modifications observed inside the NC during experimental infection in mice.

Screening of at-risk blood donors for Chagas disease in non-endemic countries: Lessons from a 2-year experience in Tuscany, Italy.

BACKGROUND: Chagas disease (CD) is caused by the protozoan parasite Trypanosoma cruzi and is transmitted by blood-sucking triatomine insects in endemic areas of Latin America. Transmission can also occur via blood transfusion and is a major cause of CD in non-endemic areas. OBJECTIVES: The aim of the study was to assess the prevalence of anti-T. cruzi antibodies in blood donors at risk of infection in Tuscany, Italy, following the introduction of blood safety Italian legislation. MATERIAL AND METHODS: Donors (N = 1985) were tested in 2016 to 2018 for anti-T. cruzi IgG using an immunochromatographic test (ICT). Chemiluminescent immunoassay (CLIA) was performed on ICT-positive donors to exclude CD, whereas enzyme-linked immunosorbent assay and western blot were performed in case of discordant results. All assays were performed on CD patients (N = 10) for validation. RESULTS: Ten blood donors had a positive ICT result, with a resulting T. cruzi seroprevalence of 0.5% but demonstrated negative results to CLIA, as well as to the other serological assays. The comparison of serological assays suggested a lower relative sensitivity of ICT. CONCLUSION: The results of this study confirm the significance of serological testing in the screening strategy for CD. However, they provide evidence for discontinuing the use of ICT as a screening test and suggest that a sensitive, specific and multi-sample format assay should be used at the national level for uniformity of results.

A 13th-century cystic echinococcosis from the cemetery of the monastery of Badia Pozzeveri (Lucca, Italy).

OBJECTIVE: To differentially diagnose a calcified formation recovered from a 13th century AD grave from the Tuscan monastery of Badia Pozzeveri, Lucca, Italy. MATERIALS: A calcified formation from the thoraco-abdominal region of a skeleton buried in the monastery cemetery. METHODS: Cone Beam Computed Tomography, Scanning Electron Microscope and Energy Dispersive X-Ray Spectroscopy. RESULTS: A hollow, calcified ovoid formation was identified as typical of a hydatid cyst, permitting the diagnosis of cystic echinococcosis in a 35-45year-old female. CONCLUSIONS: The study reveals the circulation of the parasite Echinococcus granulosus in the region of Lucca in late medieval Tuscany. SIGNIFICANCE: This finding is the fourth case of cystic echinococcosis from an archaeological context in Italy and provides insight into environmental conditions that appear to have affected members of a community, irrespective of social status. LIMITATIONS: Caution and the application of multiple analyses must be exercised in the differential diagnosis to discriminate among calcified formations. SUGGESTIONS FOR FURTHER RESEARCH: Analysis of stable isotopes of the calcified formation, such as 15N and 13C, in order to compare them with isotopic values of the host individual and to further confirm the parasitic origin of the find.