Tropical Parasitology最新文献

Introduction: Blastocystis sp. is the most common parasitic infestation in humans. However, its pathogenicity remains controversial. Our aim was to study the prevalence of Blastocystis sp. parasite subtypes in patients with gastrointestinal manifestations referred for colonoscopy and assess possible correlation with clinical, colonoscopic, and histopathological findings.

Methodology: One hundred patients with gastrointestinal manifestations referred for colonoscopy were enrolled. Stool samples were collected and examined both microscopically and by real-time quantitative polymerase chain reaction (qPCR) for detection of Blastocystis sp. Subtyping was done for positive samples by qPCR and confirmed by sequencing.

Results: qPCR sensitivity far exceeded microscopy in detection of Blastocystis sp. (58% vs. 31%, agreement 38.5%). The most commonly detected subtype was 3 (50%), followed by 2 (32.8%) and 4 (13.8%). Abdominal pain was the most common clinical symptom; inflammation and colitis were the most common abnormal colonoscopic and histopathological findings. The most frequent subtype encountered in those findings was Subtype 3.

Conclusions: This study confirmed the importance of using qPCR in diagnosis of Blastocystis sp. An association between abnormal clinical, colonoscopic, and histopathological findings on the one hand, and Blastocystis sp. infestation, especially Subtype 3, on the other hand, is also posed. This necessitates further studies to assess the mechanism of association with pathogenicity.

Context: Histidine-rich protein 2 (HRP2) detecting rapid diagnostic tests (RDTs) have played an important role in enabling prompt malaria diagnosis in remote locations. HRP2 has advantages over other biomarkers because of its abundance in the bloodstream, repetitive binding epitopes, and falciparum-specificity. Most HRP2-based RDTs also exhibit some cross-reactivity to a closely related protein (HRP3). Plasmodium falciparum parasites lacking HRP2 (pfhrp2) and 3 (pfhrp3) genes escape detection by these RDTs.

Objectives: The objective of the study was to study the sensitivity and specificity of hrp2-based RDT for diagnosis of falciparum, to compare the RDT results with microscopy and polymerase chain reaction (PCR), and to determine the prevalence of HRP2 gene deletion among the RDT-negative, microscopy-positive falciparum strains.

Materials and methods: Blood samples were collected and diagnosis was done by microscopic examination, RDTs, and PCR.

Results: Out of 1000 patients examined, 138 were positive for P. falciparum. Fever was the most common symptom followed by chills with rigor and headache were recorded among more than >95% of the study patients. Three microscopy-confirmed P. falciparum cases were negative by HRP2-based RDT and were found to have deletion of HRP2 and HRP3 exon 2.

Conclusions: Rapid and accurate diagnosis and prompt deployment of effective antimalarial medication are essential components of appropriate case management. P. falciparum strains that evade diagnosis by RDTs represent a major threat to malaria control and elimination efforts.

Parasites are uncommon causes of heart diseases except in endemic areas, and very few data are available which deals with parasites infecting human heart. However, literatures demonstrated that certain parasites such as protozoan and helminths can lead to significant cardiac complications. Although all organs can be affected, the heart and the lungs are the most frequently affected organs either directly or indirectly. It may involve all layers of the heart including pulmonary vasculature, thus producing a wide variety of clinical manifestations, which may present as myocarditis, pericarditis, cardiomyopathy, endomyocardial fibrosis, and pulmonary hypertension.

Hard ticks are mainly responsible for more "tick-borne" diseases in humans when compared to soft ticks. Tick infestation of ocular and periocular tissues is rare. We report the case of a 61-year-old male with left upper eyelid edema with erythema and live parasite on the lid margin.

Context: Toxoplasma gondii and rubella virus are microorganisms that can cause intrauterine infections and congenital anomalies in the fetus. Data regarding the simultaneous seroprevalence of these infections are not available in Senegal.

Aims: This study aimed to determine for the first time the simultaneous seroprevalence of toxoplasmosis and rubella among pregnant women in Dakar.

Materials and methods: In this retrospective study, anti-Toxoplasma and anti-rubella antibodies were analyzed in the serum samples obtained from pregnant women receiving prenatal care at Military Hospital of Ouakam between 2016 and 2021 using a chemiluminescent microparticle immunoassay for the quantitative determination of immunoglobulin G (IgG) and IgM antibodies to Toxoplasma gondii and rubella in human serum.

Results: Overall, data from 2589 women were analyzed. The median age was 29 years (interquartile range: 23.14-34.86). Serum IgG and IgM were positive for T. gondii with 35.84% and 1.66%, respectively. Rubella seroprevalence was 87.14% and 0.35%, respectively, for IgG and IgM. Seroprevalence of toxoplasmosis increases significantly with age and study period. For rubella infection, the highest seroprevalence rates were noted in the youngest age group and at the end of the study period.

Conclusions: Data from this first-time study regarding simultaneous seroprevalence of toxoplasmosis and rubella among pregnant women in Senegal indicate a continuing high risk of congenital toxoplasmosis and congenital rubella syndrome in Dakar. Further studies are needed to fully assess the efficacy of rubella vaccination in women of childbearing age.

Background: Fecal calprotectin (FC) and fecal occult blood (FOB) were suggested as potential inflammatory markers for assessing intestinal schistosomiasis morbidity that are conventionally detected through invasive methods.

Aim and objectives: The present work aimed to evaluate FC and FOB as morbidity markers of Schistosoma mansoni infection before and after praziquantel treatment.

Materials and methods: A total of 205 stool samples (117 schoolchildren and 88 adults) were collected and examined by Kato Katz. A questionnaire enquiring about diarrhea, history of blood in stool, and abdominal pain was designed and applied.

Results: S. mansoni prevalence rates were 20.5% and 11.36% among children and adults, respectively; the majority of cases had light infection intensity. FC and FOB were studied among 25 cured S. mansoni cases (17 children and 8 adults) pre and one-month post treatment. Before treatment, six and four children of moderate and high S. mansoni infection intensity tested positive for FC and FOB, respectively, all turning negative after treatment. FC showed borderline statistical significance before and after treatment among children. However, all adults tested negative for FC and FOB.

Conclusion: FC and FOB could be possibly used as morbidity monitoring tools for S. mansoni infection in children with moderate and high infection intensity.

By converging advanced science, engineering, and design, deep techs are bringing a great wave of future innovations by mastering challenges and problem complexity across sectors and the field of parasitology is no exception. Remarkable research and advancements can be seen in the field of parasite detection and diagnosis through smartphone applications. Supervised and unsupervised data deep learnings are heavily exploited for the development of automated neural network models for the prediction of parasites, eggs, etc., From microscopic smears and/or sample images with more than 99% accuracy. It is expected that several models will emerge in the future wherein greater attention is being paid to improving the model's accuracy. Invariably, it will increase the chances of adoption across the commercial sectors dealing in health and related applications. However, parasitic life cycle complexity, host range, morphological forms, etc., need to be considered further while developing such models to make the deep tech innovations perfect for bedside and field applications. In this review, the recent development of deep tech innovations focusing on human parasites has been discussed focusing on the present and future dimensions, opportunities, and applications.