Parasitic infections in hematopoietic stem cell transplant recipients.

INTRODUCTION: Hematopoietic stem cell transplantation (HSCT) is a vital treatment for various hematological disorders. However, HSCT recipients face increased risks of infectious complications due to immunosuppression. Parasitic infections are a significant concern in this vulnerable population and can lead to substantial morbidity and mortality. This review examines parasitic infections in HSCT recipients, focusing on major infections affecting different organ systems, including intestinal parasites (Giardia spp., Entamoeba histolytica, and Cryptosporidium spp.), hematologic parasites (Plasmodium spp. and Babesia spp.), and tissue/visceral parasites (Toxoplasma gondii, Leishmania spp., and Trypanosoma cruzi). METHODS: A systematic search of relevant literature was conducted and included studies up to August 2023. Databases included PubMed, Google Scholar, were queried using specific keywords related to parasitic infections in HSCT patients. The epidemiology, risk factors, clinical presentation, diagnostic methods, and treatment approaches for each infection were evaluated. RESULTS AND CONCLUSION: Knowing the epidemiology, risk factors, and clinical presentations are crucial for timely intervention and successful management. By emphasizing early detection, effective therapies, and the unique challenges posed by each of these infections, this review highlights the importance of tailored strategies for HSCT recipients. Future research can further refine management protocols to enhance care and outcomes for these patients.

Association of low birth weight and polyparasitic infection during pregnancy in Lambaréné, Gabon.

OBJECTIVE: To report the prevalence of polyparasitism during pregnancy in the Lambaréné region of Gabon and its association with newborn birth weight. METHOD: Pregnant women in their third trimester were recruited in a prospective study between November 2011 and March 2015. Parasite infection status was assessed microscopically in stool, urine and blood samples. Maternal demographic and obstetrical characteristics and newborns anthropometric data were collected. Multivariable logistic regression was used to assess the association between low birth weight and polyparasitism. RESULTS: 678 of 927 pregnant women were included for analysis with mean age (SD) of 25 (6.8) years. The analysis showed that 69% (468/678) were infected with at least one parasite (Plasmodium spp., Schistosoma spp., soil-transmitted helminths, filarial infections). This comprised of 38% with monoparasitism and 31% polyparasitism. The proportion of newborn babies with a weight below 2500 g (LBW) in our study was 21% (142/678). Compared to pregnant women without infection, women with monoparasitic infection had adjusted Odds Ratio confidence interval 95% CI (aOR [95%CI]) of 1.6 [0.95-2.73], those with two parasites had aOR 95%CI of 2.63 [1.51-4.62], and those with more than two parasites had aOR of 5.08 [2.5-10.38] for delivering a newborn with low birth weight. CONCLUSION: In Lambaréné, an endemic area for multiple parasite infections, there is a high prevalence of polyparasitism in pregnant women. Polyparasitism is associated with low birth weight. Therefore, there is an urgent need for active screening and treatment of parasite infections in pregnant women to assess the potential public health benefit of such interventions.

COVID-19 and Corticosteroids: Unfamiliar but Potentially Fatal Infections That Can Arise following Short-Course Steroid Treatment.

Corticosteroid use is increasing worldwide as recent studies confer survival benefit of corticosteroids in the management of patients with severe COVID-19. Strongyloides and amebic infections are neglected diseases that can progress to catastrophic complications in patients exposed to corticosteroids, even with short treatment courses. To prevent lethal outcomes, clinicians should be aware of the threat these two parasitic infections pose to at-risk patients receiving corticosteroids, especially in the era of COVID-19.

Marine Parasites and Disease in the Era of Global Climate Change.

Climate change affects ecological processes and interactions, including parasitism. Because parasites are natural components of ecological systems, as well as agents of outbreak and disease-induced mortality, it is important to summarize current knowledge of the sensitivity of parasites to climate and identify how to better predict their responses to it. This need is particularly great in marine systems, where the responses of parasites to climate variables are less well studied than those in other biomes. As examples of climate's influence on parasitism increase, they enable generalizations of expected responses as well as insight into useful study approaches, such as thermal performance curves that compare the vital rates of hosts and parasites when exposed to several temperatures across a gradient. For parasites not killed by rising temperatures, some simple physiological rules, including the tendency of temperature to increase the metabolism of ectotherms and increase oxygen stress on hosts, suggest that parasites' intensity and pathologies might increase. In addition to temperature, climate-induced changes in dissolved oxygen, ocean acidity, salinity, and host and parasite distributions also affect parasitism and disease, but these factors are much less studied. Finally, because parasites are constituents of ecological communities, we must consider indirect and secondary effects stemming from climate-induced changes in host-parasite interactions, which may not be evident if these interactions are studied in isolation.

Understanding how temperature shifts could impact infectious disease.

Climate change is expected to have complex effects on infectious diseases, causing some to increase, others to decrease, and many to shift their distributions. There have been several important advances in understanding the role of climate and climate change on wildlife and human infectious disease dynamics over the past several years. This essay examines 3 major areas of advancement, which include improvements to mechanistic disease models, investigations into the importance of climate variability to disease dynamics, and understanding the consequences of thermal mismatches between host and parasites. Applying the new information derived from these advances to climate-disease models and addressing the pressing knowledge gaps that we identify should improve the capacity to predict how climate change will affect disease risk for both wildlife and humans.

The Prevalence of Parasitic Contamination of Fresh Vegetables in Tehran, Iran

Objective: Parasitic diseases have created numerous health and economic problems in developing and developed countries. One of the most prevalent ways of transmitting diseases is by consuming raw vegetables that are contaminated with parasites. With respect to the importance of healthy vegetable consumption, an awareness of vegetable status helps prevent infection. Therefore, the present study was conducted to determine the level of parasitic contamination of vegetables consumed in Tehran. Methods: This descriptive and cross-sectional study was conducted on vegetable samples spread in Tehran from October 2017 to September 2018. The samples included 240 vegetables selected from 10 types of vegetable including leek, basil, mint, spring onion, radish, parsley, lettuce, cress, tarragon and coriander. Each sample was examined after passing through washing and centrifuging. Parasitic agents such as unicellular, egg and larva of the worms were studied. The data were analysed using SPSS software. Conclusion: Parasitic infection was observed in 62 samples (25.8%). The highest and lowest rates of contamination were observed in coriander and lettuce, respectively. Rhabditoid larva (12.5%; 15 cases) and Physaloptera egg (1.6%; 2 cases) were the most and least observed parasites, respectively. Other parasites such as Entamoeba, Giardia, Blastocystis, Hymenolepis, Ascaris and the egg and larva of hookworms were also observed. Despite the relative improvement of social, agricultural, economic and health conditions in Tehran, the prevalence of parasitic infections still persists. Factors such as developing modern waste collection methods, improving urban sewage systems, preventing domestic animal traffic on pastures and promoting the knowledge of different classes of people could reduce the prevalence of these types of diseases.

Interleukin (IL)-21 in Inflammation and Immunity During Parasitic Diseases.

Parasitic diseases cause significant morbidity and mortality in the developing and underdeveloped countries. No efficacious vaccines are available against most parasitic diseases and there is a critical need for developing novel vaccine strategies for care. IL-21 is a pleiotropic cytokine whose functions in protection and immunopathology during parasitic diseases have been explored in limited ways. IL-21 and its cognate receptor, IL-21R, are highly expressed in parasitized organs of infected humans as well in murine models of the human parasitic diseases. Prior studies have indicated the ability of the IL-21/IL-21R signaling axis to regulate the effector functions (e.g., cytokine production) of T cell subsets by enhancing the expression of T-bet and STAT4 in human T cells, resulting in an augmented production of IFN-γ. Mice deficient for either IL-21 (Il21-/-) or IL-21R (Il21r-/-) showed significantly reduced inflammatory responses following parasitic infections as compared with their WT counterparts. Targeting the IL-21/IL-21R signaling axis may provide a novel approach for the development of new therapeutic agents for the prevention of parasite-induced immunopathology and tissue destruction.

A parasitological evaluation of edible insects and their role in the transmission of parasitic diseases to humans and animals.

From 1 January 2018 came into force Regulation (EU) 2015/2238 of the European Parliament and of the Council of 25 November 2015, introducing the concept of "novel foods", including insects and their parts. One of the most commonly used species of insects are: mealworms (Tenebrio molitor), house crickets (Acheta domesticus), cockroaches (Blattodea) and migratory locusts (Locusta migrans). In this context, the unfathomable issue is the role of edible insects in transmitting parasitic diseases that can cause significant losses in their breeding and may pose a threat to humans and animals. The aim of this study was to identify and evaluate the developmental forms of parasites colonizing edible insects in household farms and pet stores in Central Europe and to determine the potential risk of parasitic infections for humans and animals. The experimental material comprised samples of live insects (imagines) from 300 household farms and pet stores, including 75 mealworm farms, 75 house cricket farms, 75 Madagascar hissing cockroach farms and 75 migrating locust farms. Parasites were detected in 244 (81.33%) out of 300 (100%) examined insect farms. In 206 (68.67%) of the cases, the identified parasites were pathogenic for insects only; in 106 (35.33%) cases, parasites were potentially parasitic for animals; and in 91 (30.33%) cases, parasites were potentially pathogenic for humans. Edible insects are an underestimated reservoir of human and animal parasites. Our research indicates the important role of these insects in the epidemiology of parasites pathogenic to vertebrates. Conducted parasitological examination suggests that edible insects may be the most important parasite vector for domestic insectivorous animals. According to our studies the future research should focus on the need for constant monitoring of studied insect farms for pathogens, thus increasing food and feed safety.

Parasitic Infections of the Stem Cell Transplant Recipient and the Hematologic Malignancy Patient, Including Toxoplasmosis and Strongyloidiasis.

Hematopoietic stem cell transplantation (HSCT) recipients may infrequently develop parasitic infections at the time of the procedure via contamination from allograft tissue or blood products, and in the post-transplantation period through the traditional route of infection or as a reactivation caused by immunosuppression related to the transplant. To reduce risk, efforts should be directed at performing a comprehensive history, maintaining a high index of suspicion, and adhering to preventive measures. Additional strategies for the prevention, screening and careful follow-up, identification, and pre-emptive treatment of parasitic infections are required to reduce morbidity and mortality in HSCT patients.

Parasitic infections of the spine: case series and review of the literature.

OBJECTIVEAlthough parasitic infections are endemic to parts of the developing world and are more common in areas with developing economies and poor sanitary conditions, rare cases may occur in developed regions of the world.METHODSArticles eligible for the authors' literature review were initially searched using PubMed with the phrases "parasitic infections" and "spine." After the authors developed a list of parasites associated with spinal cord infections from the initial search, they expanded it to include individual diagnoses, using search terms including "neurocysticercosis," "schistosomiasis," "echinococcosis," and "toxoplasmosis."RESULTSTwo recent cases of parasitic spinal infections from the authors' institution are included.CONCLUSIONSKey findings on imaging modalities, laboratory studies suggestive of parasitic infection, and most importantly a thorough patient history are required to correctly diagnose parasitic spinal infections.

Medical Parasitology Taxonomy Update, 2016-2017.

Parasite taxonomy continues to change as molecular and morphologic studies enhance our understanding of parasite relatedness. This minireview builds on the information provided in the last taxonomy update in this journal to summarize new and revised clinically relevant human parasite taxonomic changes that have occurred in 2016 and 2017.

Prevalence of Intestinal Parasites in Raw Vegetables Consumed by Inhabitants of Mymensingh City.

Uncooked vegetables are an important part of a healthy diet in different parts of the world. The present descriptive cross sectional type of study was carried out to determine the parasitological contamination of vegetables sold at markets of Mymensingh city of Bangladesh. Parasitological examinations were performed in material derived from 200 specimens of 10 different vegetables to detect intestinal parasites in the department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2015 to July 2016. Each sample was washed with 5 liter distilled water, then washing fluid was centrifuged and resulting sediment was collected for iodine and normal saline wet mount slide preparation to detect human pathogenic intestinal parasites by microscopic examination. Out of 200 vegetable samples, 123(61.5%) were contaminated with different species of parasites. The vegetables red amaranth had the highest contamination rate of 18/20 (90%) followed by jute leaf 17/20 (85%), coriander leaf 15/20 (75%), onion 14/20 (70%), lady's finger 14/20 (70%), radish 13/20 (65%), green pepper 12/20 (60%), carrot 12/20 (60%), cucumber 5/20 (25%), tomato 3/20 (15%). Among the contaminating parasites Ascaris lumbricoides (egg) 36.5% was the most prevalent followed by Strongyloides stercoralis (larva) 35.5%, Entamoeba histolytica ( trophozoite and different cystic stages) 8.5%, Hook worm (egg and larva) 6.5% , Balantidium coli (trophozoite) 4.0%, Enterobius vermicularis (egg) 3.5%, Trichuris trichiura (egg) 1.5%, Giardia lamblia (cyst) 1.0%. To our knowledge, it was the first base line study pursued in Bangladesh. Contamination of raw vegetables from markets with pathogenic parasites would increase the risk of disease to the population that consumes or works with these products. So improperly washed raw eaten vegetables should be considered a potential risk for contracting parasites, particularly helminthes in Mymensingh city.

Seafood-borne parasitic diseases in Australia: are they rare or underdiagnosed?

Australia is a multicultural country surrounded by water where seafood is regularly consumed. Literature suggests that some popular edible fish sold in fish markets may be infected with parasites transmissible to humans (notably, anisakids and other helminths); however the number of reported human cases due to these parasites is low. In this article we critically review topical publications to understand whether the low number of human infection is due to lack of expertise in Australia to identify and diagnose accurately seafood-borne parasitic infections. The risk these parasites pose to humans may be underestimated due to: (i) errors or inability of diagnosing these infections, primarily due to less sensitive and specific serological tests and misidentifying parasites without a taxonomist in the diagnostic team; and (ii) medical practitioners not being aware of these parasites or not considering them in the differential diagnosis even in patients with history of regular raw or undercooked seafood consumption.

Parasitic Diseases that can Infect Travelers to Africa.

Travel is important in the spread of diseases, and the number of travelers is increasing daily. Therefore, the importance of the diseases that occur during or after travel is increasing. In underdeveloped countries in particular, parasitic diseases are epidemic or endemic, and these diseases lead to high numbers of deaths. People traveling from developed to underdeveloped countries have a higher risk of transmission of parasitic diseases during travel. Fifteen percent of the world's population lives in Africa. In terms of geography, economics, and development, the continent is divided into four regions: East Africa, South Africa, North Africa, and West Africa. In recent years, international travels to Africa have been increasing. During these travels, there is a risk of contracting parasitic diseases, such as malaria, schistosomiasis, trypanosomiasis (African sleeping disease), onchocerciasis, lymphatic filariasis, and leishmaniasis. Before traveling to Africa, it is vital to take measures against diseases in the region.

Response to comment on "Oestrogen-induced angiogenesis and implantation contribute to the development of parasitic myomas after laparoscopic morcellation".

According to the literature review, CO2 insufflation on parasitic myoma implantation is not well studied, and we concur that our study is related to "Morcellation-induced parasitic myomas." We did not compare CO2 insufflation to non-insufflation in our study. The reason is the efficacy of gasless laparoscopic myomectomy and morcellation is not well established and this modality is seldom performed. Moreover, the effects of pneumoperitoneum on mesothelial cells and the role of the entire peritoneal cavity as a cofactor in adhesion formation have become well established, the role of CO2 insufflation in the establishment of parasitic myomas has not yet been studied. As such, more in-depth and well-designed studies for the role of CO2 insufflation are needed.

Effects of temperature-humidity index on health and growth performance in Japanese black calves.

We evaluated the relationship between the temperature-humidity index (THI) and health and growth performance in Japanese black calves in Japan. Data were collected from medical records of 19,313 Japanese black calves aged up to 3 months for correlation analysis with THI from July 2008 to June 2011. Data were also collected on the market weights of 57,144 Japanese black calves, and we calculated the body weight gain (BWG) of each calf based on body weight and age in days at the calf market. Analysis for the relationship between disease incidence and THI demonstrated a negative correlation (r = -0.54, p < 0.01). In addition, the mean disease incidence at THI of ≤50 was significantly higher than that at THI of ≥71. Analysis for the relationship between growth performance in calves and THI revealed that a lower THI during the month of birth was associated with a lower BWG at the calf market and that BWG with THI of ≤70 was significantly lower than that with THI of ≥71 (p < 0.05). In contrast, a higher mean THI during the third month after birth was associated with a lower BWG at the calf market, and BWG with THI of >75 was significantly lower than that with THI of ≤50 or THI ranging from 56 to 60 (p < 0.05). These results indicate that Japanese black calves are susceptible to a cold environment immediately after birth, whereas they are susceptible to a heat environment 3 months after birth.

Oestrogen-induced angiogenesis and implantation contribute to the development of parasitic myomas after laparoscopic morcellation.

BACKGROUND: Iatrogenic parasitic myomas (PMs), caused by intra-corporeal power morcellation during laparoscopy is gradually increasing. However, the pathogenesis and medical treatment of PMs remain largely unelucidated. METHODS: Laparoscopically-induced PM xenografted mouse model was conducted by xenografting human uterine myoma fragments into the abdominal cavity of SCID mice and hormonal manipulation was performed using this mouse model to demonstrate the role of oestrogen in the development of implanted PMs. Immunohistochemistry of oestrogen receptor α (ERα), progesterone receptor (PR), vimentin, vascular endothelial growth factor (VEGF), microvessel density (MVD) and Ki-67 index was performed and compared. RESULTS: In the patient with PMs, ERα, PR, angiogenesis and proliferative property expression were upregulated in PM lesions compared to uterine myomas. In the laparoscopically-induced PM mouse model, implanted myomas had more steroid receptor expressions, angiogenesis and proliferative property compared with pre-xenografted or non-implanted myoma. Depletion of oestrogen in the ovariectomized (OVX) mice decreased laparoscopically-induced PM implantations. In comparison, the implantations of PMs were increased with additional E2 supplement. Hormonal manipulation in the PM mouse model, including AI, GnRHa and SERM groups, were compared and AI significantly decreased the implantations, steroid receptor, angiogenesis, cell density, and proliferative index of PMs compared with control group. Furthermore, GnRHa significantly decreased VEGF and MVD expressions compared with control group. CONCLUSIONS: These data highlight the crucial role of oestrogen in the development of laparoscopically-induced PMs and suggest that hormone manipulation may be a potential therapeutic agent. TRIAL REGISTRATION: This protocol was approved by the Human and Animal Institutional Review Board of Taipei Veterans General Hospital ( VGHIRB No 2014-10-002C on Nov. 17th, 2014; IACUC 2014-119 on Aug. 22nd, 2014).

Infectious diseases in allogeneic haematopoietic stem cell transplantation: prevention and prophylaxis strategy guidelines 2016.

Infectious complications after allogeneic haematopoietic stem cell transplantation (allo-HCT) remain a clinical challenge. This is a guideline provided by the AGIHO (Infectious Diseases Working Group) of the DGHO (German Society for Hematology and Medical Oncology). A core group of experts prepared a preliminary guideline, which was discussed, reviewed, and approved by the entire working group. The guideline provides clinical recommendations for the preventive management including prophylactic treatment of viral, bacterial, parasitic, and fungal diseases. The guideline focuses on antimicrobial agents but includes recommendations on the use of vaccinations. This is the updated version of the AGHIO guideline in the field of allogeneic haematopoietic stem cell transplantation utilizing methods according to evidence-based medicine criteria.

Cancer and life-history traits: lessons from host-parasite interactions.

Despite important differences between infectious diseases and cancers, tumour development (neoplasia) can nonetheless be closely compared to infectious disease because of the similarity of their effects on the body. On this basis, we predict that many of the life-history (LH) responses observed in the context of host-parasite interactions should also be relevant in the context of cancer. Parasites are thought to affect LH traits of their hosts because of strong selective pressures like direct and indirect mortality effects favouring, for example, early maturation and reproduction. Cancer can similarly also affect LH traits by imposing direct costs and/or indirectly by triggering plastic adjustments and evolutionary responses. Here, we discuss how and why a LH focus is a potentially productive but under-exploited research direction for cancer research, by focusing our attention on similarities between infectious disease and cancer with respect to their effects on LH traits and their evolution. We raise the possibility that LH adjustments can occur in response to cancer via maternal/paternal effects and that these changes can be heritable to (adaptively) modify the LH traits of their offspring. We conclude that LH adjustments can potentially influence the transgenerational persistence of inherited oncogenic mutations in populations.