-
Intensive Care Medicine Feb 2020An increasing number of critically ill patients are immunocompromised. Acute hypoxemic respiratory failure (ARF), chiefly due to pulmonary infection, is the leading... (Review)
Review
An increasing number of critically ill patients are immunocompromised. Acute hypoxemic respiratory failure (ARF), chiefly due to pulmonary infection, is the leading reason for ICU admission. Identifying the cause of ARF increases the chances of survival, but may be extremely challenging, as the underlying disease, treatments, and infection combine to create complex clinical pictures. In addition, there may be more than one infectious agent, and the pulmonary manifestations may be related to both infectious and non-infectious insults. Clinically or microbiologically documented bacterial pneumonia accounts for one-third of cases of ARF in immunocompromised patients. Early antibiotic therapy is recommended but decreases the chances of identifying the causative organism(s) to about 50%. Viruses are the second most common cause of severe respiratory infections. Positive tests for a virus in respiratory samples do not necessarily indicate a role for the virus in the current acute illness. Invasive fungal infections (Aspergillus, Mucorales, and Pneumocystis jirovecii) account for about 15% of severe respiratory infections, whereas parasites rarely cause severe acute infections in immunocompromised patients. This review focuses on the diagnosis of severe respiratory infections in immunocompromised patients. Special attention is given to newly validated diagnostic tests designed to be used on non-invasive samples or bronchoalveolar lavage fluid and capable of increasing the likelihood of an early etiological diagnosis.
Topics: Humans; Immunocompromised Host; Intensive Care Units; Invasive Fungal Infections; Parasitic Diseases; Pneumonia, Bacterial; Respiratory Insufficiency; Respiratory Tract Infections
PubMed: 32034433
DOI: 10.1007/s00134-019-05906-5 -
Microbiology Spectrum Aug 2016Parasites are an important cause of human disease worldwide. The clinical severity and outcome of parasitic disease is often dependent on the immune status of the host.... (Review)
Review
Parasites are an important cause of human disease worldwide. The clinical severity and outcome of parasitic disease is often dependent on the immune status of the host. Specific parasitic diseases discussed in this chapter are amebiasis, giardiasis, cryptosporidiosis, cyclosporiasis, cystoisosporiasis, microsporidosis, granulomatous amebic encephalitis, toxoplasmosis, leishmaniasis, Chagas disease, malaria, babesiosis, strongyloidiasis, and scabies.
Topics: Animals; Humans; Parasites; Parasitic Diseases
PubMed: 27726821
DOI: 10.1128/microbiolspec.DMIH2-0013-2015 -
Nature Reviews. Immunology Feb 2015Type I interferons (IFNs) have diverse effects on innate and adaptive immune cells during infection with viruses, bacteria, parasites and fungi, directly and/or... (Review)
Review
Type I interferons (IFNs) have diverse effects on innate and adaptive immune cells during infection with viruses, bacteria, parasites and fungi, directly and/or indirectly through the induction of other mediators. Type I IFNs are important for host defence against viruses. However, recently, they have been shown to cause immunopathology in some acute viral infections, such as influenza virus infection. Conversely, they can lead to immunosuppression during chronic viral infections, such as lymphocytic choriomeningitis virus infection. During bacterial infections, low levels of type I IFNs may be required at an early stage, to initiate cell-mediated immune responses. High concentrations of type I IFNs may block B cell responses or lead to the production of immunosuppressive molecules, and such concentrations also reduce the responsiveness of macrophages to activation by IFNγ, as has been shown for infections with Listeria monocytogenes and Mycobacterium tuberculosis. Recent studies in experimental models of tuberculosis have demonstrated that prostaglandin E2 and interleukin-1 inhibit type I IFN expression and its downstream effects, demonstrating that a cross-regulatory network of cytokines operates during infectious diseases to provide protection with minimum damage to the host.
Topics: Animals; Bacterial Infections; Communicable Diseases; Humans; Interferon Type I; Mycoses; Parasitic Diseases; Signal Transduction; Virus Diseases
PubMed: 25614319
DOI: 10.1038/nri3787 -
Frontiers in Immunology 2021
Topics: Animals; Disease Vectors; Evolution, Molecular; Host-Parasite Interactions; Humans; Immune System; Parasitic Diseases
PubMed: 34367192
DOI: 10.3389/fimmu.2021.729415 -
Microbiology Spectrum Jun 2016Gastrointestinal infections in the immunocompromised host are caused by the common bacterial, viral, fungal, and parasitic agents that also cause infections in the... (Review)
Review
Gastrointestinal infections in the immunocompromised host are caused by the common bacterial, viral, fungal, and parasitic agents that also cause infections in the immunocompetent host. Of special consideration is that immunocompromised patients may be at increased risk for infection or disease severity and by pathogens not seen in the competent host. This chapter reviews the various agents, risk factors, and diagnostic approaches to detect gastrointestinal infections in this patient population.
Topics: Bacterial Infections; Gastrointestinal Diseases; Humans; Immunocompromised Host; Mycoses; Opportunistic Infections; Parasitic Diseases; Virus Diseases
PubMed: 27337464
DOI: 10.1128/microbiolspec.DMIH2-0005-2015 -
Turkiye Parazitolojii Dergisi Jun 2020MicroRNAs (miRNAs), as epigenetic regulators, are small non-coding RNAs regulating gene expression in eukaryotes at the post-transcriptional level to control biological... (Review)
Review
MicroRNAs (miRNAs), as epigenetic regulators, are small non-coding RNAs regulating gene expression in eukaryotes at the post-transcriptional level to control biological functions. MicroRNAs play a role in development, physiology, infection, immunity and the complex life cycles of parasites. Also, parasite infection can alter host miRNA expression that might result in either parasite clearance or infection. Over the past 20 years, thousands of miRNAs have been identified in the nematode and other parasites. Thus, miRNA pathways are potential targets for the diagnostic and therapeutic control of parasitic diseases. Here, we review the current status and potential functions of miRNAs related to protozoans, helminths, and arthropods.
Topics: Animals; Arthropods; Caenorhabditis elegans; Helminths; Humans; MicroRNAs; Parasites; Parasitic Diseases; RNA, Protozoan
PubMed: 32482043
DOI: 10.4274/tpd.galenos.2020.6776 -
The American Journal of Tropical... Jan 2024
Topics: Humans; Animals; Parasitic Diseases; Ectoparasitic Infestations; Arthropods
PubMed: 37983909
DOI: 10.4269/ajtmh.23-0275 -
Frontiers in Immunology 2023Malaria and leishmaniasis are endemic parasitic diseases in tropical and subtropical countries. Although the overlap of these diseases in the same host is frequently... (Review)
Review
Malaria and leishmaniasis are endemic parasitic diseases in tropical and subtropical countries. Although the overlap of these diseases in the same host is frequently described, co-infection remains a neglected issue in the medical and scientific community. The complex relationship of concomitant infections with spp. and spp. is highlighted in studies of natural and experimental co-infections, showing how this "dual" infection can exacerbate or suppress an effective immune response to these protozoa. Thus, a infection preceding or following infection can impact the clinical course, accurate diagnosis, and management of leishmaniasis, and vice versa. The concept that in nature we are affected by concomitant infections reinforces the need to address the theme and ensure its due importance. In this review we explore and describe the studies available in the literature on spp. and spp. co-infection, the scenarios, and the factors that may influence the course of these diseases.
Topics: Humans; Coinfection; Leishmaniasis; Malaria; Leishmania; Plasmodium
PubMed: 36895563
DOI: 10.3389/fimmu.2023.1122411 -
Neurology India 2023Neuropsychiatric disorders, ranging from mild cognitive impairment to frank psychosis, have been associated with certain parasitic infections. The parasite may cause... (Review)
Review
Neuropsychiatric disorders, ranging from mild cognitive impairment to frank psychosis, have been associated with certain parasitic infections. The parasite may cause damage to the central nervous system in several ways: as a space-occupying lesion (neuro-cysticercosis), alteration of neurotransmitters (toxoplasmosis), generation of the inflammatory response (trypanosomiasis, schistosomiasis), hypovolemic neuronal injury (cerebral malaria), or a combination of these. Certain drugs like quinacrine (mepacrine), mefloquine, quinolone, and interferon alpha which are used to treat these parasitic infections can further cause neuropsychiatric adverse effects. This review summarizes the major parasitic infections that are associated with neuropsychiatric disorders and the pathogenesis involved in their processes. A high index of suspicion for parasitic diseases, especially in endemic areas, should be kept in patients presenting with neuropsychiatric symptoms. A multidimensional approach to identification of the offending parasite using serological, radiological, and molecular tests is required not only to ensure proper and prompt treatment of the primary parasitic infection but also to improve the prognosis of patients by complete resolution of neuropsychiatric symptoms.
Topics: Humans; Parasitic Diseases; Central Nervous System; Mental Disorders; Mefloquine; Cysticercosis
PubMed: 37148042
DOI: 10.4103/0028-3886.375424 -
The Biochemical Journal Sep 2021Lactate is the main product generated at the end of anaerobic glycolysis or during the Warburg effect and its role as an active signalling molecule is increasingly... (Review)
Review
Lactate is the main product generated at the end of anaerobic glycolysis or during the Warburg effect and its role as an active signalling molecule is increasingly recognised. Lactate can be released and used by host cells, by pathogens and commensal organisms, thus being essential for the homeostasis of host-microbe interactions. Infection can alter this intricate balance, and the presence of lactate transporters in most human cells including immune cells, as well as in a variety of pathogens (including bacteria, fungi and complex parasites) demonstrates the importance of this metabolite in regulating host-pathogen interactions. This review will cover lactate secretion and sensing in humans and microbes, and will discuss the existing evidence supporting a role for lactate in pathogen growth and persistence, together with lactate's ability to impact the orchestration of effective immune responses. The ubiquitous presence of lactate in the context of infection and the ability of both host cells and pathogens to sense and respond to it, makes manipulation of lactate a potential novel therapeutic strategy. Here, we will discuss the preliminary research that has been carried out in the context of cancer, autoimmunity and inflammation.
Topics: Animals; Bacteria; Bacterial Infections; Fungi; Host-Pathogen Interactions; Humans; Lactic Acid; Monocarboxylic Acid Transporters; Mycoses; Parasites; Parasitic Diseases; Virus Diseases; Viruses
PubMed: 34492096
DOI: 10.1042/BCJ20210263