Histoplasmosis In Animals Research Articles

Animal Histoplasmosis in Europe: Review of the Literature and Molecular Typing of the Etiological Agents.

Histoplasmosis has been previously diagnosed in animals from Europe. The aim of this study is to review the literature on these reports, to analyze cases diagnosed at our laboratory (2000–2022) and to improve molecular typing of Histoplasma capsulatum directly from tissue to study the molecular epidemiology of Histoplasma capsulatum causing animal infections in Europe. Including 15 cases studied in our laboratory, we identified 39 cases of animal histoplasmosis between 1968 and 2022. They were diagnosed mostly in superficial tissue biopsies from cats and badgers from Central Europe. Using phylogenetic analyses of six partial genes, we were able to classify eight of the etiological agents as belonging to a highly supported lineage within the Eurasian clade. This study confirms the occurrence of autochthonous histoplasmosis in animals in Central Europe and proposes the addition of new loci to the MLST scheme to study the molecular epidemiology of histoplasmosis using either formalin-fixed paraffin-embedded tissue and fresh or cadaveric biopsies.

Immunomodulatory effects of pharmaceutical opioids and antipyretic analgesics: Mechanisms and relevance to infection.

Understanding how pharmaceutical opioids and antipyretic analgesics interact with the immune system potentially has major clinical implications for management of patients with infectious diseases and surgical and critical care patients. An electronic search was carried out on MEDLINE, EMBASE, PsycINFO, CENTRAL and the Cochrane library to identify reports describing the immunomodulatory effects of opioid analgesics and antipyretic analgesics, and their effects in infectious diseases. In adaptive immunity, nonsteroidal anti-inflammatory drugs have divergent effects: augmenting cell-mediated immunity but inhibiting humoral immunity. Nonsteroidal anti-inflammatory drugs have demonstrated a beneficial role in Mycobacterium tuberculosis infection and histoplasmosis in animals, and may be plausible adjuvants to antimicrobial agents in these diseases. There is a need to evaluate these findings rigorously in human clinical trials. There is preliminary evidence demonstrating antiviral effects of indomethacin in SARS CoV-2 in vitro; however, uncertainty regarding its clinical benefit in humans needs to be resolved in large clinical trials. Certain opioid analgesics are associated with immunosuppressive effects, with a developing understanding that fentanyl, morphine, methadone and buprenorphine suppress innate immunity, whilst having diverse effects on adaptive immunity. Morphine suppresses key cells of the innate immunity and is associated with greater risk of infection in the postsurgical setting. Efforts are needed to achieve adequate analgesia whilst avoiding suppression of the innate immunity in the immediate postoperative period caused by certain opioids, particularly in cancer surgery.

Histopathological identification of histoplasmosis in animals at Dhaka Zoo

Dhaka Zoo with 2000 animal heads of 184 species from significant genetic diversity and five million visitors’ influx round the year is placing it a public health important spot. This study was conducted to investigate histoplasmosis in animals at Dhaka Zoo to ascertain animal health, welfare and public health safety standard. One hundred and two necropsied tissue samples preserved in 10% neutral buffered formalin at necropsy from 36 animals of 25 different species were collected from Dhaka Zoo during 2007 - 2009. Twenty five out of 36 study animals were suffering from granulomatous diseases of mycotic and/or bacterial origin. Among them three animals were found suffering from histoplasmosis. Clinical history, nodular lesions from necropsy findings, granulomatous reactions with fungal spores on histopathology; macrophages laden with histoplasma organisms on histopathology and on special staining were revealed histoplasmosis in six rhesus macaques (Macaca mulatta). Present study provides evidence of existing histoplasmosis and similar long standing zoonotic diseases in majority of rest of the animals with health risk that shades health safety standard at Dhaka Zoo.DOI: http://dx.doi.org/10.3329/bjvm.v11i2.19145Bangl. J. Vet. Med. (2013). 11 (2):177-181

Modulation of cellular immune responses in mice with disseminated histoplasmosis by recombinant interleukin-2.

Depression of the cellular immune responses in mice with disseminated histoplasmosis is associated with deficient production of interleukin-2 (IL-2) by splenocytes. Therefore, we examined whether a highly purified preparation of IL-2, recombinant human IL-2 (rIL-2), could modify the cellular immune responses in infected mice and whether this lymphokine could alter the severity of histoplasmosis in animals. Exogenous rIL-2, at concentrations of up to 1,000 U/ml, failed to augment the proliferative responses to concanavalin A by unfractionated splenocytes or splenic T cells from mice infected for 1 week. In addition, rIL-2 did not modulate the plaque-forming cell response to sheep erythrocytes by splenocytes from these same mice. However, at week 3, rIL-2 in concentrations ranging from 10 to 1,000 U/ml considerably augmented the proliferative response to concanavalin A and plaque-forming cell response to sheep erythrocytes by splenocytes from infected mice. Kinetics studies demonstrated that rIL-2 exerted maximal immunoregulatory activity when added on day 0 or 1 to cultures of splenocytes. In vivo administration of rIL-2, 200 to 20,000 U/day, for 10 days to normal and 3-week-infected mice did not alter the proliferative activity of splenocytes to concanavalin A; 200,000 U of rIL-2 per day actually depressed the proliferative responses of splenocytes from normal and infected mice. In vivo, rIL-2 did not modify delayed-type hypersensitivity responses to sheep erythrocytes or to histoplasmin by normal and infected mice. Moreover, treatment with rIL-2 in vivo did not reduce the number of Histoplasma CFU in spleens of mice. Thus, despite the immunoenhancing effect of rIL-2 in vitro, this lymphokine failed to exert similar effects in vivo.

Possible role for cysteine biosynthesis in conversion from mycelial to yeast form of Histoplasma capsulatum.

Histoplasma capsulatum is a pathogenic dimorphic fungus which causes histoplasmosis in animals and man. The free-living saprobic form found in soil is mycelial, but, on infection, or in the laboratory, when the temperature is raised from 23 to 37 °C, it converts reversibly to a unicellular, parasitic yeast-like form. Little is known about the biochemistry of this process. There have been reports of quantitative and qualitative differences in the chemical composition of the two forms1,2, and of changes in RNA metabolism during the conversion3. Also, whereas extracts from the yeast phase cells contain multiple species of RNA polymerase, those from mycelia have only traces of activity, but contain an inhibitor of RNA polymerase4. The yeast and mycelial cells differ in sensitivity to amphotericin B (a polyene) and actinomycin D5, but there is no significant enzymatic difference between the two phases with respect to the glycolytic pathway and the tricarboxylic acid cycle6. The initiation of conversion requires a temperature change and also low oxidation–reduction potential (O/R) of the growth medium7, but the maintenance of the yeast phase requires sulphur-containing organic compounds, especially cysteine8,9. The possibility of a nutritional requirement for –SH groups has been suggested10 but not explored. We now report that the yeast cells lack the enzyme sulphite reductase so that they cannot reduce inorganic sulphite to sulphide, and thus cannot synthesise cysteine. In contrast, mycelial cells, with active reductase, can grow without cysteine supplement.

Occurrence of histoplasmosis in Asia.

The occurrence of histoplasmosis in Asia has been reviewed. Authentic cases of histoplasmosis in man are known from India, Malaysia, Singapore, Indonesia, Thailand, South Vietnam and Japan, but the autochthonous nature of the cases reported has not been established unequivocally. Of the 30 cases of human histoplasmosis recorded from Asia, 15 were confirmed by positive cultures, and their country-wise distribution is as follows: Malaysia — 4, Indonesia — 3, Singapore — 2, Thailand — 2, South Vietnam — 2 and one each from India and Japan. Authentic cases of histoplasmosis in animals are currently unknown from Asia, and likewise there is no information on the natural habitats of the etiologic agentH. capsulatum in this part of the world except for a solitary isolation from soil in bat-infested cave in Malaysia.

DIVISION OF MYCOLOGY: HISTOPLASMOSIS IN ANIMALS

Transactions of the New York Academy of SciencesVolume 11, Issue 7 Series II p. 248-254 DIVISION OF MYCOLOGY: HISTOPLASMOSIS IN ANIMALS C. W. EMMONS, C. W. EMMONS The Laboratory of Infectious Diseases, Microbiological Institute, National Institutes of Health, Bethesda, Maryland. This paper, illustrated with lantern slides, was presented before the meeting of the Division on April 22, 1949.Search for more papers by this author C. W. EMMONS, C. W. EMMONS The Laboratory of Infectious Diseases, Microbiological Institute, National Institutes of Health, Bethesda, Maryland. This paper, illustrated with lantern slides, was presented before the meeting of the Division on April 22, 1949.Search for more papers by this author First published: May 1949 https://doi.org/10.1111/j.2164-0947.1949.tb00315.xCitations: 18 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume11, Issue7 Series IIMay 1949Pages 248-254 RelatedInformation