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1.
Front Immunol ; 15: 1279043, 2024.
Article in English | MEDLINE | ID: mdl-38840916

ABSTRACT

Schistosomiasis remains the most devastating neglected tropical disease, affecting over 240 million people world-wide. The disease is caused by the eggs laid by mature female worms that are trapped in host's tissues, resulting in chronic Th2 driven fibrogranulmatous pathology. Although the disease can be treated with a relatively inexpensive drug, praziquantel (PZQ), re-infections remain a major problem in endemic areas. There is a need for new therapeutic drugs and alternative drug treatments for schistosomiasis. The current study hypothesized that cysteinyl leukotrienes (cysLTs) could mediate fibroproliferative pathology during schistosomiasis. Cysteinyl leukotrienes (cysLTs) are potent lipid mediators that are known to be key players in inflammatory diseases, such as asthma and allergic rhinitis. The present study aimed to investigate the role of cysLTR1 during experimental acute and chronic schistosomiasis using cysLTR1-/- mice, as well as the use of cysLTR1 inhibitor (Montelukast) to assess immune responses during chronic Schistosoma mansoni infection. Mice deficient of cysLTR1 and littermate control mice were infected with either high or low dose of Schistosoma mansoni to achieve chronic or acute schistosomiasis, respectively. Hepatic granulomatous inflammation, hepatic fibrosis and IL-4 production in the liver was significantly reduced in mice lacking cysLTR1 during chronic schistosomiasis, while reduced liver pathology was observed during acute schistosomiasis. Pharmacological blockade of cysLTR1 using montelukast in combination with PZQ reduced hepatic inflammation and parasite egg burden in chronically infected mice. Combination therapy led to the expansion of Tregs in chronically infected mice. We show that the disruption of cysLTR1 is dispensable for host survival during schistosomiasis, suggesting an important role cysLTR1 may play during early immunity against schistosomiasis. Our findings revealed that the combination of montelukast and PZQ could be a potential prophylactic treatment for chronic schistosomiasis by reducing fibrogranulomatous pathology in mice. In conclusion, the present study demonstrated that cysLTR1 is a potential target for host-directed therapy to ameliorate fibrogranulomatous pathology in the liver during chronic and acute schistosomiasis in mice.


Subject(s)
Acetates , Cyclopropanes , Disease Models, Animal , Mice, Knockout , Quinolines , Receptors, Leukotriene , Schistosomiasis mansoni , Sulfides , Animals , Receptors, Leukotriene/metabolism , Mice , Cyclopropanes/therapeutic use , Cyclopropanes/pharmacology , Acetates/therapeutic use , Acetates/pharmacology , Sulfides/therapeutic use , Sulfides/pharmacology , Schistosomiasis mansoni/drug therapy , Schistosomiasis mansoni/immunology , Schistosomiasis mansoni/parasitology , Quinolines/therapeutic use , Quinolines/pharmacology , Female , Schistosoma mansoni/immunology , Chronic Disease , Leukotriene Antagonists/pharmacology , Leukotriene Antagonists/therapeutic use , Liver/parasitology , Liver/pathology , Liver/metabolism , Liver/immunology , Mice, Inbred C57BL , Praziquantel/therapeutic use , Praziquantel/pharmacology , T-Lymphocytes, Regulatory/immunology
2.
BMC Vet Res ; 20(1): 207, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38760783

ABSTRACT

BACKGROUND: Although ultrasonography (US) has been widely used in the diagnosis of human diseases to monitor the progress of cystic echinococcosis (CE) control, the screening method for hepatic CE in sheep flocks requires adjustment. In this study, we used a US scanner to screen sheep flocks and evaluated the efficacy of dosing dogs once a year with praziquantel for 7 years from 2014 to 2021. METHODS: All sheep in the three flocks were screened using an ultrasound scanner in 2014 and compared with the prevalence of infection in 2021 in Bayinbuluke, Xinjiang, China. Sheep age was determined using incisor teeth. Cyst activity and calcification were determined using US images. The dogs were dewormed with praziquantel once a year to control echinococcosis in the community. RESULTS: Three flocks had 968 sheep in 2014, with 13.22%, 22.62%, 18.7%, 27.27%, 11.88%, and 6.3% of sheep aged 1, 2, 3, 4, 5, and ≥ 6 years old, respectively. US scanning revealed that the overall CE prevalence was 38.43% (372/968), with active cysts and calcified cysts present in 9.40% (91/968) and 29.02% (281/968) of the sheep, respectively. For the young sheep aged 1 and 2 years, the prevalence of active and calcified cysts was: 1.56% and 0.91%, and 10.94% and 18.72%, respectively. Approximately 15.15% and 16.52% of the 4- and 5-year-old sheep, respectively, harbored active cysts. There was no significant difference in the infection rates of sheep between 2014 and 2021 (P > 0.05). CONCLUSIONS: US is a practical tool for the field screening of CE in sheep flocks. One-third of the sheep population in the flocks was 1-2 years old, and these sheep played a very limited role in CE transmission, as most of the cysts were calcified. Old sheep, especially culled aged sheep, play a key role in the transmission of CE. Dosing dogs once a year did not affect echinococcosis control.


Subject(s)
Echinococcosis, Hepatic , Sheep Diseases , Ultrasonography , Animals , Sheep Diseases/epidemiology , Sheep Diseases/parasitology , Sheep Diseases/diagnostic imaging , Sheep , China/epidemiology , Ultrasonography/veterinary , Echinococcosis, Hepatic/veterinary , Echinococcosis, Hepatic/epidemiology , Echinococcosis, Hepatic/diagnostic imaging , Prevalence , Dogs , Praziquantel/therapeutic use , Anthelmintics/therapeutic use , Female
3.
PLoS One ; 19(5): e0300384, 2024.
Article in English | MEDLINE | ID: mdl-38758736

ABSTRACT

BACKGROUND: Hundreds of millions of doses of Praziquantel (PZQ) have been administered to persons with and without schistosomiasis living in schistosomiasis endemic settings, through the mass drug administration (MDA) strategy which started in the early 2000s. A recent publication suggested high risk of PZQ-related visual disorders, raising public health concerns. We aim to systematically synthesize evidence on the magnitude of PZQ-related visual disorders. METHODS: We will search PubMed, Google Scholar, CINAHL, SCOPUS, CENTRAL and LILACS from 1977 (when the first human clinical trials on PZQ started) to 31st May 2024, with no language restrictions. The key search terms will include "Praziquantel", "PZQ", "visual disorder", "adverse events", "side effects", "blurry vision" and "visual impairment" together with alternative terms and synonyms. All the countries endemic for schistosomiasis will be included as search terms. We will also search HINARI, Africa Journals Online, Thesis Databases and Preprint Repositories. Where necessary, we will contact expert researchers working in the field of schistosomiasis, UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR), pharmaceutical industries, country-specific Food and Drug Authorities (FDAs) and the European Medicines Agency databases. We will search Conference Proceedings and reference lists of relevant studies for additional studies. At least two authors will independently select studies, extract data and assess risk of bias in the included studies. Any disagreements or discrepancies will be resolved through discussion between the reviewers. Heterogeneity will be explored graphically, and statistically using the I2-statistic. We will conduct random-effects meta-analysis when heterogeneity is appreciable, and express dichotomous outcomes (visual adverse events including excessive lacrimation, blurry vision and visual impairments) as risk ratio (RR) or Odds Ratio (OR) with their 95% confidence interval (CI). We will perform subgroup analysis to assess the impact of heterogeneity, and sensitivity analyses to test the robustness of the effect estimates. The overall level of evidence will be assessed using GRADE. EXPECTED OUTCOMES: The present review expects to identify and categorize visual disorders occurring after administration of PZQ, alone or in combination with other drugs. By synthesizing the data from multiple studies, the review aims to present a quantitative assessment of the risk or odds of experiencing a visual disorder in different populations after ingesting PZQ. The review will also generate insights into whether PZQ in combination with other drugs are associated with increased odds of visual disorders and whether the occurrence of visual disorders correlates with dosage or treatment duration. Policymakers, public health experts and stakeholders could rely on the review findings to deliver context-sensitive preventive chemotherapy programs by adjusting drug combinations or dosing schedules to reduce risk of visual adverse effects in populations treated with PZQ. The review aims to identify gaps in the current evidence regarding visual disorders following PZQ administration in schistosomiasis endemic settings which can serve as the basis for future research on important but unanswered questions. DISSEMINATION AND PROTOCOL REGISTRATION: The findings of this study will be disseminated through stakeholder forums, conferences, and peer-review publications. The review protocol has been registered in the International Prospective Register for Systematic Reviews (PROSPERO)- CRD42023417963.


Subject(s)
Mass Drug Administration , Praziquantel , Schistosomiasis , Systematic Reviews as Topic , Vision Disorders , Humans , Schistosomiasis/epidemiology , Schistosomiasis/prevention & control , Schistosomiasis/drug therapy , Praziquantel/therapeutic use , Praziquantel/adverse effects , Praziquantel/administration & dosage , Vision Disorders/epidemiology , Vision Disorders/chemically induced , Meta-Analysis as Topic , Endemic Diseases/prevention & control , Anthelmintics/therapeutic use , Anthelmintics/administration & dosage , Anthelmintics/adverse effects
5.
Parasitol Res ; 123(5): 215, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38771511

ABSTRACT

Schistosomiasis is a neglected tropical disease associated with considerable morbidity. Praziquantel (PZQ) is effective against adult schistosomes, yet, it has little effect on juvenile stages, and PZQ resistance is emerging. Adopting the drug repurposing strategy as well as assuming enhancing the efficacy and lessening the doses and side effects, the present study aimed to investigate the in vivo therapeutic efficacy of the widely used antiarrhythmic, amiodarone, and diuretic, spironolactone, and combinations of them compared to PZQ. Mice were infected by Schistosoma mansoni "S. mansoni" cercariae (Egyptian strain), then they were divided into two major groups: Early- [3 weeks post-infection (wpi)] and late- [6 wpi] treated. Each group was subdivided into seven subgroups: positive control, PZQ, amiodarone, spironolactone, PZQ combined with amiodarone, PZQ combined with spironolactone, and amiodarone combined with spironolactone-treated groups. Among the early-treated groups, spironolactone had the best therapeutic impact indicated by a 69.4% reduction of total worm burden (TWB), 38.6% and 48.4% reduction of liver and intestine egg load, and a significant reduction of liver granuloma number by 49%. Whereas, among the late-treated groups, amiodarone combined with PZQ was superior to PZQ alone evidenced by 96.1% reduction of TWB with the total disappearance of female and copula in the liver and intestine, 53.1% and 84.9% reduction of liver and intestine egg load, and a significant reduction of liver granuloma number by 67.6%. Comparatively, spironolactone was superior to PZQ and amiodarone in the early treatment phase targeting immature stages, while amiodarone had a more potent effect when combined with PZQ in the late treatment phase targeting mature schistosomes.


Subject(s)
Amiodarone , Disease Models, Animal , Praziquantel , Schistosoma mansoni , Schistosomiasis mansoni , Animals , Schistosomiasis mansoni/drug therapy , Schistosomiasis mansoni/parasitology , Mice , Schistosoma mansoni/drug effects , Praziquantel/therapeutic use , Praziquantel/pharmacology , Amiodarone/therapeutic use , Amiodarone/pharmacology , Female , Spironolactone/therapeutic use , Spironolactone/pharmacology , Schistosomicides/therapeutic use , Schistosomicides/pharmacology , Male , Anthelmintics/therapeutic use , Anthelmintics/pharmacology , Treatment Outcome , Drug Therapy, Combination , Liver/parasitology
6.
Sci Rep ; 14(1): 11730, 2024 05 22.
Article in English | MEDLINE | ID: mdl-38778126

ABSTRACT

Metabolism of praziquantel (PZQ), a racemic mixture and the only drug approved to treat S. mansoni infection, is mediated by genetically polymorphic enzymes. Periodic school-based mass drug administration (MDA) with PZQ is the core intervention to control schistosomiasis. However data on the impact of pharmacogenetic variation, nutrition, and infection status on plasma PZQ exposure is scarce. We investigated genetic and non-genetic factors influencing PZQ plasma concentration and its metabolic ratios (trans-4-OH-PZQ/PZQ and cis-4-OH-PZQ/PZQ). Four hundred forty-six school children aged 7-15 years from four primary schools in southern Ethiopia who received albendazole and PZQ preventive chemotherapy through MDA campaign were enrolled. Genotyping for common functional variants of CYP3A4 (*1B), CYP3A5 (*3, *6), CYP2C19 (*2, *3, *17), CYP2C9 (*2, *3), and CYP2J2*7 was performed. Plasma concentrations of PZQ, trans-4-OH-PZQ, and cis-4-OH-PZQ were quantified using UPLCMS/MS. Carriers of CYP2C19 defective variant alleles (*2 and *3) had significantly higher mean PZQ plasma concentration than CYP2C19*1/*1 or *17 carriers (p = 0.005). CYP2C19*1/*1 and CYP2C19*17 carriers had higher trans-4-OH-PZQ/PZQ and cis-4-OH-PZQ/PZQ metabolic ratios compared with CYP2C19*2 or *3 carriers (p < 0.001). CYP2J2*7 carriers had lower mean PZQ plasma concentration (p = 0.05) and higher trans-4-OH-PZQ/PZQ and cis-4-OH-PZQ/PZQ metabolic ratios. Male participants had significantly higher PZQ concentration (p = 0.006) and lower metabolic ratios (p = 0.001) than females. There was no significant effect of stunting, wasting, S. mansoni or soil-transmitted helminth infections, CYP3A4, CYP3A5, or CYP2C9 genotypes on plasma PZQ or its metabolic ratios. In conclusion, sex, CYP2C19 and CYP2J2 genotypes significantly predict PZQ plasma exposure among Ethiopian children. The impact of CYP2C19 and CYP2J2 genotypes on praziquantel treatment outcomes requires further investigation.


Subject(s)
Cytochrome P-450 CYP2C19 , Cytochrome P-450 Enzyme System , Genotype , Praziquantel , Humans , Praziquantel/blood , Praziquantel/pharmacokinetics , Child , Male , Female , Ethiopia , Adolescent , Cytochrome P-450 CYP2C19/genetics , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Anthelmintics/blood , Anthelmintics/pharmacokinetics , Anthelmintics/therapeutic use , Schistosomiasis mansoni/drug therapy , Schistosomiasis mansoni/blood , Schistosomiasis mansoni/genetics , Schistosomiasis mansoni/parasitology
7.
Molecules ; 29(9)2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38731401

ABSTRACT

The burden of human schistosomiasis, a known but neglected tropical disease in Sub-Saharan Africa, has been worrisome in recent years. It is becoming increasingly difficult to tackle schistosomiasis with praziquantel, a drug known to be effective against all Schistosoma species, due to reports of reduced efficacy and resistance. Therefore, this study seeks to investigate the antischistosomal potential of phytochemicals from Azadirachta indica against proteins that have been implicated as druggable targets for the treatment of schistosomiasis using computational techniques. In this study, sixty-three (63) previously isolated and characterized phytochemicals from A. indica were identified from the literature and retrieved from the PubChem database. In silico screening was conducted to assess the inhibitory potential of these phytochemicals against three receptors (Schistosoma mansoni Thioredoxin glutathione reductase, dihydroorotate dehydrogenase, and Arginase) that may serve as therapeutic targets for schistosomiasis treatment. Molecular docking, ADMET prediction, ligand interaction, MMGBSA, and molecular dynamics simulation of the hit compounds were conducted using the Schrodinger molecular drug discovery suite. The results show that Andrographolide possesses a satisfactory pharmacokinetic profile, does not violate the Lipinski rule of five, binds with favourable affinity with the receptors, and interacts with key amino acids at the active site. Importantly, its interaction with dihydroorotate dehydrogenase, an enzyme responsible for the catalysis of the de novo pyrimidine nucleotide biosynthetic pathway rate-limiting step, shows a glide score and MMGBSA of -10.19 and -45.75 Kcal/mol, respectively. In addition, the MD simulation shows its stability at the active site of the receptor. Overall, this study revealed that Andrographolide from Azadirachta indica could serve as a potential lead compound for the development of an anti-schistosomal drug.


Subject(s)
Azadirachta , Dihydroorotate Dehydrogenase , Molecular Docking Simulation , Oxidoreductases Acting on CH-CH Group Donors , Schistosomiasis , Azadirachta/chemistry , Animals , Schistosomiasis/drug therapy , Oxidoreductases Acting on CH-CH Group Donors/antagonists & inhibitors , Oxidoreductases Acting on CH-CH Group Donors/metabolism , Humans , Phytochemicals/pharmacology , Phytochemicals/chemistry , Molecular Dynamics Simulation , Schistosoma mansoni/drug effects , Schistosoma mansoni/enzymology , NADH, NADPH Oxidoreductases/antagonists & inhibitors , NADH, NADPH Oxidoreductases/metabolism , Plant Extracts/chemistry , Plant Extracts/pharmacology , Computer Simulation , Schistosomicides/pharmacology , Schistosomicides/chemistry , Schistosomicides/therapeutic use , Multienzyme Complexes/antagonists & inhibitors , Multienzyme Complexes/metabolism , Praziquantel/pharmacology , Praziquantel/chemistry , Praziquantel/therapeutic use
8.
Parasitology ; 151(4): 421-428, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38576256

ABSTRACT

Cystic echinococcosis (CE), caused by the larval stage of the cestode Echinococcus granulosus, is one of the most widespread zoonoses in Mediterranean countries. Baiting not-owned dogs with praziquantel (PZQ), due to their key role in the maintaining the transmission of CE, currently appears to be the most effective way to limit the transmission of CE, as well as an important aspect to introduce for the control of this parasitic disease. Therefore, this study aims to test 3 types of PZQ-based baits by evaluating different parameters (integrity over time, attractiveness and palatability for dogs, and mechanical resistance after release to different altitudes) and the bait acceptance in field by target animals, i.e. not-owned dogs, by using camera traps. The double PZQ-laced baits (with a double layer of highly palatable chews) showed the greatest resistance in the environment while also preserving the attractiveness and palatability up to 10 days, also withstood heights of 25 m, thus resulting as the most suitable also for drone delivery. The results on the field showed that most of the baits were consumed by not-owned dogs (82.2%), while the remaining were consumed by wild boars (8.9%), foxes (6.7%), badgers (1.1%) and hedgehogs (1.1%), confirming the specific and high attractiveness of the double PZQ-laced baits for the target population and highlights how an anthelmintic baiting programme may be a viable tool for the management of E. granulosus among free-ranging dog populations in endemic rural areas.


Subject(s)
Dog Diseases , Echinococcosis , Echinococcus granulosus , Praziquantel , Animals , Dogs , Echinococcus granulosus/drug effects , Echinococcosis/veterinary , Echinococcosis/prevention & control , Echinococcosis/parasitology , Dog Diseases/parasitology , Dog Diseases/prevention & control , Praziquantel/pharmacology , Anthelmintics/pharmacology , Zoonoses/parasitology , Swine
9.
PLoS Negl Trop Dis ; 18(4): e0012101, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38620032

ABSTRACT

BACKGROUND: Schistosomiasis is endemic in Nigeria, and the treatment is largely concentrated on children enrolled in schools. Consequently, the coverage of non-enrolled school-aged children is often neglected. Ajagba and Awosan are two communities in Nigeria that have never had any control intervention. Hence, this survey was designed to determine the endemicity of urogenital schistosomiasis and to evaluate the efficacy of a single-dose praziquantel in the communities. METHODS: Urine sample (10 mL) of each participant from Ajagba and Awosan communities was filtered through 12µm polycarbonate filter. The filter was placed on a microscope slide, and stained with a drop of 1% Lugol iodine solution. The stained slides were examined under the microscope and the numbers of S. haematobium eggs were counted. Water contact sites were searched for snail hosts and the snails collected were shed for Schistosoma cercariae. Data were analyzed using SPSS version 24.0 and the significance level was set at 95%. RESULTS: The overall prevalence of infection in the Ajagba community was 45.6% with a mean intensity of 61.1 ± 144.5 eggs/10 mL of urine, while the prevalence of infection in the Awosan community was 5.7% with a mean intensity of 1.4 ± 6.8 eggs/10 mL of urine. The school-aged children had a prevalence and mean intensity of infection of 73.1% and 111.6 ± 177.9 eggs/10 mL of urine, respectively. Following treatment, women had a higher egg reduction rate than men (p = 0.0283). Bulinus globosus were found in Ajagba but not in Awosan, with 5.7% shedding Schistosoma spp, cercariae. CONCLUSION: Urogenital schistosomiasis was hyperendemic in the Ajagba community, and hypoendemic in the Awosan community. The presence of Bulinus globosus supported the transmission of the schistosomiasis in the Ajagba community. Communities where schistosomiasis is still actively transmitted in Nigeria should be identified for effective intervention through the MDA programs.


Subject(s)
Anthelmintics , Praziquantel , Rural Population , Schistosoma haematobium , Schistosomiasis haematobia , Nigeria/epidemiology , Humans , Praziquantel/administration & dosage , Praziquantel/therapeutic use , Child , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/epidemiology , Animals , Female , Male , Adolescent , Schistosoma haematobium/drug effects , Anthelmintics/administration & dosage , Anthelmintics/therapeutic use , Adult , Young Adult , Prevalence , Snails/parasitology , Child, Preschool , Middle Aged , Endemic Diseases , Parasite Egg Count
10.
Parasitol Res ; 123(4): 180, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38592544

ABSTRACT

Because of recent reports of praziquantel resistance in schistosome infections, there have been suggestions to employ ivermectin as a possible alternative, especially as its chemical composition is different from that of praziquantel, so cross-resistance is not expected. In order to ascertain possible damage and elimination of worms, we used ivermectin by oral gavage in infected mice, at a high dose (30.1 mg/kg, bordering toxicity). We also tested the efficacy of the drug at various times postinfection (PI), to check on possible effect on young and mature stages of the parasites. Thus, we treated mice on days 21 and 22 or on days 41 and 42 and even on days 21, 22, 41, and 42 PI. None of the treatment regimens resulted in cure rates or signs of lessened pathology in the mice. We also compared the effect of ivermectin to that of artemisone, an artemisinin derivative which had served us in the past as an effective anti-schistosome drug, and there was a stark difference in the artemisone's efficacy compared to that of ivermectin; while ivermectin was not effective, artemisone eliminated most of the worms, prevented egg production and granulomatous inflammatory response. We assume that the reported lack of activity of ivermectin, in comparison with praziquantel and artemisinins, originates from the difference in their mode of action. In wake of our results, we suggest that ivermectin is not a suitable drug for treatment of schistosomiasis.


Subject(s)
Artemisinins , Schistosomatidae , Schistosomiasis , Animals , Mice , Praziquantel/therapeutic use , Ivermectin/therapeutic use , Schistosomiasis/drug therapy
11.
Int Marit Health ; 75(1): 49-54, 2024.
Article in English | MEDLINE | ID: mdl-38647059

ABSTRACT

Schistosomiasis, caused by Schistosoma trematode worms, represents a significant global health challenge. This review offers a thorough examination of the disease's epidemiology, transmission dynamics, diagnostic modalities, and treatment options. Diagnostic techniques encompass direct parasitological methods, immunological assays, DNA/RNA detection, and biomarker utilization, each with distinct advantages and limitations. There is an urgent need for improved diagnostic tools with enhanced sensitivity and specificity. Praziquantel remains the cornerstone of treatment, exhibiting efficacy against all Schistosoma species, while the potential of artemisin derivatives in combination therapy is also explored. In this review, we focus on the importance of praziquantel administration as the central aspect of schistosomiasis treatment, highlighting ongoing efforts to optimize its utilization for improved patient outcomes.


Subject(s)
Anthelmintics , Praziquantel , Schistosomiasis , Praziquantel/therapeutic use , Humans , Schistosomiasis/drug therapy , Schistosomiasis/diagnosis , Anthelmintics/therapeutic use , Animals , Schistosoma/drug effects
12.
Parasitology ; 151(5): 523-528, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38571299

ABSTRACT

Dipylidium caninum is a common tapeworm of dogs. Two cases of praziquantel resistance have been described in D. caninum in the United States. No further reports have been published to the authors' knowledge. Here, the case of a dog imported to Switzerland from Spain with a history of chronic excretion of tapeworm proglottids and unresponsiveness to praziquantel treatments is reported. Clinical signs were mild (restlessness, tenesmus, anal pruritus, squashy feces) and flea infestation could be ruled out. Infection with D. caninum was confirmed through morphological and genetic parasite identification. Different subsequently applied anthelmintic compounds and protocols, including epsiprantel, did not confer the desired effects. Proglottid shedding only stopped after oral mebendazole administration of 86.2 mg kg−1 body weight for 5 consecutive days. Clinical signs resolved and the dog remained coproscopically negative during a follow-up period of 10 months after the last treatment. This case represents the first reported apparent praziquantel and epsiprantel resistance in D. caninum in Europe. Treatment was extremely challenging especially due to the limited availability of efficacious alternative compounds.


Subject(s)
Anthelmintics , Cestode Infections , Dog Diseases , Drug Resistance , Praziquantel , Animals , Praziquantel/therapeutic use , Praziquantel/pharmacology , Praziquantel/administration & dosage , Dogs , Dog Diseases/parasitology , Dog Diseases/drug therapy , Anthelmintics/pharmacology , Anthelmintics/therapeutic use , Cestode Infections/drug therapy , Cestode Infections/veterinary , Cestode Infections/parasitology , Switzerland , Cestoda/drug effects , Spain , Feces/parasitology , Male
13.
PLoS Negl Trop Dis ; 18(3): e0011939, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38536863

ABSTRACT

Cystic Echinococcosis (CE) as a prevalent tapeworm infection of human and herbivorous animals worldwide, is caused by accidental ingestion of Echinococcus granulosus eggs excreted from infected dogs. CE is endemic in the Middle East and North Africa, and is considered as an important parasitic zoonosis in Iran. It is transmitted between dogs as the primary definitive host and different livestock species as the intermediate hosts. One of the most important measures for CE control is dog deworming with praziquantel. Due to the frequent reinfection of dogs, intensive deworming campaigns are critical for breaking CE transmission. Dog reinfection rate could be used as an indicator of the intensity of local CE transmission in endemic areas. However, our knowledge on the extent of reinfection in the endemic regions is poor. The purpose of the present study was to determine E. granulosus reinfection rate after praziquantel administration in a population of owned dogs in Kerman, Iran. A cohort of 150 owned dogs was recruited, with stool samples collected before praziquantel administration as a single oral dose of 5 mg/kg. The re-samplings of the owned dogs were performed at 2, 5 and 12 months following initial praziquantel administration. Stool samples were examined microscopically using Willis flotation method. Genomic DNA was extracted, and E. granulosus sensu lato-specific primers were used to PCR-amplify a 133-bp fragment of a repeat unit of the parasite genome. Survival analysis was performed using Kaplan-Meier method to calculate cumulative survival rates, which is used here to capture reinfection dynamics, and monthly incidence of infection, capturing also the spatial distribution of disease risk. Results of survival analysis showed 8, 12 and 17% total reinfection rates in 2, 5 and 12 months following initial praziquantel administration, respectively, indicating that 92, 88 and 83% of the dogs had no detectable infection in that same time periods. The monthly incidence of reinfection in total owned dog population was estimated at 1.5% (95% CI 1.0-2.1). The results showed that the prevalence of echinococcosis in owned dogs, using copro-PCR assay was 42.6%. However, using conventional microscopy, 8% of fecal samples were positive for taeniid eggs. Our results suggest that regular treatment of the dog population with praziquantel every 60 days is ideal, however the frequency of dog dosing faces major logistics and cost challenges, threatening the sustainability of control programs. Understanding the nature and extent of dog reinfection in the endemic areas is essential for successful implementation of control programs and understanding patterns of CE transmission.


Subject(s)
Dog Diseases , Echinococcosis , Echinococcus granulosus , Humans , Dogs , Animals , Praziquantel/therapeutic use , Iran/epidemiology , Reinfection , Farms , Echinococcosis/drug therapy , Echinococcosis/epidemiology , Echinococcosis/veterinary , Echinococcus granulosus/genetics , Feces/parasitology , Dog Diseases/drug therapy , Dog Diseases/epidemiology , Dog Diseases/parasitology
14.
PLoS Negl Trop Dis ; 18(3): e0011798, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38536861

ABSTRACT

OBJECTIVE: Female Genital Schistosomiasis (FGS) causes intravaginal lesions and symptoms that could be mistaken for sexually transmitted diseases or cancer. In adults, FGS lesions [grainy sandy patches (GSP), homogenous yellow patches (HYP), abnormal blood vessels and rubbery papules] are refractory to treatment. The effect of treatment has never been explored in young women; it is unclear if gynaecological investigation will be possible in this young age group (16-23 years). We explored the predictors for accepting anti-schistosomal treatment and/or gynaecological reinvestigation in young women, and the effects of anti-schistosomal mass-treatment (praziquantel) on the clinical manifestations of FGS at an adolescent age. METHOD: The study was conducted between 2011 and 2013 in randomly selected, rural, high schools in Ilembe, uThungulu and Ugu Districts, KwaZulu-Natal Province, East Coast of South Africa. At baseline, gynaecological investigations were conducted in female learners in grades 8 to 12, aged 16-23 years (n = 2293). Mass-treatment was offered in the low-transmission season between May and August (a few in September, n = 48), in accordance with WHO recommendations. Reinvestigation was offered after a median of 9 months (range 5-14 months). Univariate, multivariable and logistic regression analysis were used to measure the association between variables. RESULTS: Prevalence: Of the 2293 learners who came for baseline gynaecological investigations, 1045 (46%) had FGS lesions and/or schistosomiasis, 209/1045 (20%) had GSP; 208/1045 (20%) HYP; 772/1045 (74%) had abnormal blood vessels; and 404/1045 (39%) were urine positive. Overall participation rate for mass treatment and gynaecological investigation: Only 26% (587/2293) learners participated in the mass treatment and 17% (401/2293) participated in the follow up gynaecological reinvestigations. Loss to follow-up among those with FGS: More than 70% of learners with FGS lesions at baseline were lost to follow-up for gynaecological investigations: 156/209 (75%) GSP; 154/208 (74%) HYP; 539/722 (75%) abnormal blood vessels; 238/404 (59%) urine positive. The grade 12 pupil had left school and did not participate in the reinvestigations (n = 375; 16%). Follow-up findings: Amongst those with lesions who came for both treatment and reinvestigation, 12/19 still had GSP, 8/28 had HYP, and 54/90 had abnormal blood vessels. Only 3/55 remained positive for S. haematobium ova. Factors influencing treatment and follow-up gynaecological investigation: HIV, current water contact, water contact as a toddler and urinary schistosomiasis influenced participation in mass treatment. Grainy sandy patches, abnormal blood vessels, HYP, previous pregnancy, current water contact, water contact as a toddler and father present in the family were strongly associated with coming back for follow-up gynaecological investigation. Challenges in sample size for follow-up analysis of the effect of treatment: The low mass treatment uptake and loss to follow up among those who had baseline FGS reduced the chances of a larger sample size at follow up investigation. However, multivariable analysis showed that treatment had effect on the abnormal blood vessels (adjusted odds ratio = 2.1, 95% CI 1.1-3.9 and p = 0.018). CONCLUSION: Compliance to treatment and gynaecological reinvestigation was very low. There is need to embark on large scale awareness and advocacy in schools and communities before implementing mass-treatment and investigation studies. Despite challenges in sample size and significant loss to follow-up, limiting the ability to fully understand the treatment's effect, multivariable analysis demonstrated a significant treatment effect on abnormal blood vessels.


Subject(s)
Genital Diseases, Female , Schistosomiasis haematobia , Adult , Pregnancy , Animals , Female , Adolescent , Humans , Praziquantel/therapeutic use , South Africa , Schistosoma haematobium , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/epidemiology , Schistosomiasis haematobia/diagnosis , Genitalia, Female , Water
15.
Parasite Immunol ; 46(3): e13030, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38498004

ABSTRACT

In previous studies, the inhibitory effect of chloroquine on NLRP3 inflammasome and heme production was documented. This may be employed as a double-bladed sword in schistosomiasis (anti-inflammatory and parasiticidal). In this study, chloroquine's impact on schistosomiasis mansoni was investigated. The parasitic load (worm/egg counts and reproductive capacity index [RCI]), i-Nos/Arg-1 expression, splenomegaly, hepatic insult and NLRP3-immunohistochemical expression were assessed in infected mice after receiving early and late repeated doses of chloroquine alone or dually with praziquantel. By early treatment, the least RCI was reported in dually treated mice (41.48 ± 28.58) with a significant reduction in worm/egg counts (3.50 ± 1.29/2550 ± 479.58), compared with either drug alone. A marked reduction in the splenic index was achieved by prolonged chloroquine administration (alone: 43.15 ± 5.67, dually: 36.03 ± 5.27), with significantly less fibrosis (15 ± 3.37, 14.25 ± 2.22) than after praziquantel alone (20.5 ± 2.65). Regarding inflammation, despite the praziquantel-induced significant decrease in NLRP3 expression, the inhibitory effect was marked after dual and chloroquine administration (liver: 3.13 ± 1.21/3.45 ± 1.23, spleen: 5.7 ± 1.6/4.63 ± 2.41). i-Nos RNA peaked with early/late chloroquine administration (liver: 68.53 ± 1.8/57.78 ± 7.14, spleen: 63.22 ± 2.06/62.5 ± 3.05). High i-Nos echoed with a parasiticidal and hepatoprotective effect and may indicate macrophage-1 polarisation. On the flip side, the chloroquine-induced low Arg-1 seemed to abate immune tolerance and probably macrophage-2 polarisation. Collectively, chloroquine synergised the praziquantel-schistosomicidal effect and minimised tissue inflammation, splenomegaly and hepatic fibrosis.


Subject(s)
Rodent Diseases , Schistosomiasis mansoni , Animals , Mice , Chloroquine/pharmacology , Down-Regulation , Drug Repositioning , Inflammation , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Parasite Load , Praziquantel/pharmacology , Schistosomiasis mansoni/drug therapy , Splenomegaly
16.
Acta Trop ; 254: 107196, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38521124

ABSTRACT

BACKGROUND: The drug of choice for the treatment of opisthorchiasis caused by trematodes Opisthorchis viverrini and O. felineus is praziquantel (PZQ), but there is a constant search for new anthelmintics, including those of plant origin. Positive results on the use of artemisinin derivatives against O. viverrini opisthorchiasis have been shown previously, but the effect of these compounds on O. felineus has not been studied. Therefore, here, a comparative analysis of anthelmintic properties of artemisinin derivatives (artesunate [AS], artemether [AM], and dihydroartemisinin [DHA]) was carried out in vitro in relation to PZQ. Experiments were performed on newly excysted metacercariae (NEMs) and adult flukes of O. felineus. RESULTS: Dose- and time-dependent effects of artemisinin derivatives and of PZQ were assessed in terms of motility and mortality of both NEMs and adult flukes. The most pronounced anthelmintic action was exerted by DHA, whose half-maximal inhibitory concentrations (IC50) of 1.9 (NEMs) and 2.02 µg/mL (adult flukes) were lower than those of PZQ (0.56 and 0.25 µg/mL, respectively). In contrast to PZQ, the effects of DHA and AS were similar when we compared the two developmental stages of O. felineus (NEMs and adult flukes). In addition, AM, AS, and especially DHA at doses of 100 µg/mL disrupted tegument integrity in adult flukes, which was not observed with PZQ. CONCLUSIONS: Artemisinin derivatives (AS, AM, and DHA) have good anthelmintic efficacy against the trematode O. felineus, and the action of these substances is comparable to (and sometimes better than) the effects of PZQ.


Subject(s)
Anthelmintics , Artemisinins , Opisthorchis , Animals , Artemisinins/pharmacology , Opisthorchis/drug effects , Anthelmintics/pharmacology , Inhibitory Concentration 50 , Praziquantel/pharmacology , Survival Analysis , Artemether/pharmacology , Artesunate/pharmacology , Dose-Response Relationship, Drug
17.
Am J Trop Med Hyg ; 110(4): 677-680, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38460198

ABSTRACT

Unlike praziquantel, artemisinin derivatives are effective against juvenile schistosome worms. We assessed the efficacy and safety of a single oral dose of artesunate plus sulfalene-pyrimethamine versus praziquantel in the treatment of Schistosoma mansoni. Seventy-three schoolchildren (aged 9-15 years) with confirmed S. mansoni infection in Rarieda, western Kenya, were randomly assigned to receive either a single oral dose of artesunate plus sulfalene-pyrimethamine (n = 39) or a single dose of praziquantel (n = 34). The cure and egg reduction rates at 4 weeks posttreatment were 69.4% (25/36) versus 80.6% (25/31) (P = 0.297) and 99.1% versus 97.5% (P = 0.607) in the artesunate plus sulfalene-pyrimethamine group versus praziquantel group, respectively. Fourteen children developed adverse events, and there were no serious adverse events. A single oral dose of artesunate plus sulfalene-pyrimethamine has efficacy comparable to that of praziquantel in the treatment of S. mansoni, but these results should be confirmed in larger randomized controlled trials.


Subject(s)
Anthelmintics , Artemisinins , Schistosomiasis mansoni , Sulfalene , Adolescent , Animals , Child , Humans , Anthelmintics/therapeutic use , Artemisinins/adverse effects , Artesunate/therapeutic use , Drug Therapy, Combination , East African People , Kenya , Praziquantel/adverse effects , Pyrimethamine/therapeutic use , Schistosoma mansoni , Schistosomiasis mansoni/drug therapy , Sulfalene/pharmacology , Sulfalene/therapeutic use , Treatment Outcome
18.
Parasitol Int ; 101: 102878, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38452972

ABSTRACT

OBJECTIVE: A case description of a rare occurrence of female genital schistosomiasis affecting the upper genital tract that presented with features mimicking an ovarian neoplasm. CASE REPORT: Female genital schistosomiasis is a neglected clinical manifestation of the water-born parasitic disease which occurs due to the presence of schistosome eggs in the genitalia of women. A 23-year-old nulliparous woman presented with progressive abdominal distension. An abdominopelvic CT scan revealed a multilobulated right adnexal mass with gross ascites. Diagnosis of schistosomiasis was made by histology of biopsied specimens following laparotomy. Cervical colposcopic findings were consistent with female genital schistosomiasis. She was successfully treated with praziquantel. CONCLUSION: Female genital schistosomiasis of the upper genital tract can mimic an ovarian malignancy. Hence there is a need for its consideration as a differential diagnosis in patients with non-classical presentations of pelvic tumours in schistosomiasis-endemic areas.


Subject(s)
Ovarian Neoplasms , Praziquantel , Female , Humans , Ovarian Neoplasms/diagnosis , Ovarian Neoplasms/pathology , Ovarian Neoplasms/drug therapy , Praziquantel/therapeutic use , Diagnosis, Differential , Young Adult , Anthelmintics/therapeutic use , Schistosomiasis haematobia/diagnosis , Schistosomiasis haematobia/drug therapy , Schistosomiasis/diagnosis , Schistosomiasis/drug therapy , Animals
19.
Expert Opin Pharmacother ; 25(4): 409-420, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38511392

ABSTRACT

INTRODUCTION: Schistosomiasis, one of the current Neglected Tropical Diseases (NTDs) affects over 230 million people globally, with nearly 700 million at risk in more than 74 countries. Praziquantel (PZQ) has served as the primary treatment for the past four decades; however, its effectiveness is limited as it solely eliminates adult worms. In regions where infections are frequent, PZQ exhibits only temporary efficacy and has restricted potential to disrupt the prolonged transmission of the disease. AREAS COVERED: A comprehensive exploration using the PubMed database was conducted to review current pharmacotherapy approaches for schistosomiasis. This review also encompasses recent research findings related to potential novel therapeutics and the repurposing of existing drugs. EXPERT OPINION: Current schistosoma treatment strategies, primarily relying on PZQ, face challenges like temporary effectiveness and limited impact on disease transmission. Drug repurposing, due to economic constraints, is decisive for NTDs. Despite PZQ's efficacy, its failure to prevent reinfection highlights the need for complementary strategies, especially in regions with persistent environmental foci. Integrating therapies against diverse schistosome stages boosts efficacy and impedes resistance. Uncovering novel agents is essential to address resistance concerns in tackling this neglected tropical disease. Integrated strategies present a comprehensive approach to navigate the complex challenges.


Subject(s)
Drug Repositioning , Neglected Diseases , Praziquantel , Schistosomiasis , Schistosomicides , Humans , Schistosomiasis/drug therapy , Animals , Praziquantel/therapeutic use , Neglected Diseases/drug therapy , Neglected Diseases/prevention & control , Schistosomicides/therapeutic use , Drug Resistance , Schistosoma/drug effects
20.
Am J Trop Med Hyg ; 110(6): 1080-1088, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38531095

ABSTRACT

Disseminated cysticercosis is defined by multiple brain lesions and involvement of other body sites. Cysticidal treatment in disseminated cysticercosis is considered life-threatening. We conducted a systematic review of all published cases and case series to assess the safety and efficacy of cysticidal treatment. We conducted a systematic review in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO CRD42022331895) to assess the safety and efficacy of cysticidal treatment. Using the search term "disseminated neurocysticercosis OR disseminated cysticercosis," databases like PubMed, Scopus, Embase, and Google Scholar were searched. Outcomes included death and secondary measures like clinical improvement and lesion reduction. We calculated the predictors of primary outcome (death) using the binary logistic regression analysis. We reviewed 222 published cases from 101 publications. Approximately 87% cases were reported from India. Of 222 cases, 134 (60%) received cysticidal treatment. Follow-up information was available from 180 patients, 11 of them died, and 169 showed clinical improvement. The death rate was 4% (5 out of 114) in patients treated with cysticidal drugs plus corticosteroids, in comparison with 13% (5 out of 38) in patients who were treated with corticosteroids alone. All patients using only praziquantel faced fatality. Death predictors identified were altered sensorium and lack of treatment with albendazole. We noted that the risk of death after cysticidal treatment is not as we expected, and a multicentric randomized controlled trial is needed to resolve this issue.


Subject(s)
Cysticercosis , Neurocysticercosis , Humans , Treatment Outcome , Neurocysticercosis/drug therapy , Neurocysticercosis/mortality , Cysticercosis/drug therapy , Cysticercosis/mortality , Anthelmintics/therapeutic use , Albendazole/therapeutic use , Praziquantel/therapeutic use , Male , Adrenal Cortex Hormones/therapeutic use , Female , Adult
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