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Infestations, insect bites, and stings
Published in Rashmi Sarkar, Anupam Das, Sumit Sethi, Concise Dermatology, 2021
This is a distinctive migrating eruption caused by larvae from animal species which temporarily grow within human skin but cannot complete their life cycle in the human host. It is most commonly caused by the larvae of Ancylostoma caninum, which are excreted in dog feces and contaminate sandy beaches (particularly above the high-water line where the sand is never washed). Visitors sitting or standing on the beach may develop a creeping eruption on the affected skin as the larva moves slowly within the skin, advancing 1–2 mm per day (Figure 4.9). This creates a dramatic clinical picture and some irritation of the host skin. The condition may be treated with topical thiabendazole, or oral ivermectin; untreated, it usually resolves spontaneously after several weeks.
Intestinal Inflammation in the Parasitized Host
Published in William J. Snape, Stephen M. Collins, Effects of Immune Cells and Inflammation on Smooth Muscle and Enteric Nerves, 2020
A great practical advantage of maintaining T. spiralis in the laboratory is that the life cycle is completed in a single host. This contrasts favorably with other parasites that inhabit the small intestine and which have been utilized extensively for experimental purposes. For example, maintenance of the life cycle of Nippostrongylus brasiliensis, a hookworm-like nematode of the rat11, and Ancylostoma caninum and A. ceylanicum12, hookworms of dogs, requires the in vitro culture of infective larval forms from ova collected from the host’s feces. Thus, perpetuation of parasites possessing free-living larval stages in their life cycles requires much more time, effort, expertise, and chance for failure compared with the maintenance of T. spiralis.
The Influence of Hormones on Infectious and Parasitic Disease
Published in Istvan Berczi, Pituitary Function and Immunity, 2019
Mortality and necrosis in the heart was greater in male mice than in females, after infection with a heart adapted strain of Coxsackie B-3 virus. Castration of the males prior to infection reduced mortality and the development of autoimmune T lymphocytes. This could be reversed by testosterone and antagonized by estrone treatment.53 Male Swiss mice are more susceptible to infection with Ancylostoma caninum than are females. Orchidectomy decreased the survival of filariform larvae in males, whereas ovariectomy increased larval survival in females significantly.54
Multifocal Chorioretinitis with Serous Macular Detachment in Diffuse Unilateral Subacute Neuroretinitis (DUSN): Unique Presentation and a Diagnostic Dilemma
Published in Ocular Immunology and Inflammation, 2023
Amit Kumar Deb, Jawahar Satya Babu, Priyanka Ramanathan, Sandip Sarkar, Goutham Raja, Charita Abburu
Diffuse unilateral subacute neuroretinitis (DUSN) is an infectious, progressive retinal disorder resulting in severe visual disturbances.1 The parasitic organisms most commonly implicated are Baylisascaris procyonis, Ancylostoma caninum, and Toxocara canis.2 DUSN commonly presents as a unilateral condition in children and young adults, but bilaterality has also been observed.3 Clinical manifestations in the acute phase includes mild vitreous inflammation, optic disc edema, gray-white retinal lesions, and pigmentary changes in retinal epithelium. Late-stage DUSN is characterized multifocal choroiditis, progressive retinal pigmentary epithelial (RPE) changes, narrowing of retinal arteriole, and optic disc atrophy.1,4 Serous macular detachment in DUSN has not been reported before in the literature. Serous detachment with multifocal choroiditis is commonly seen in conditions like Vogt–Koyanagi–Harada (VKH) syndrome, sympathetic ophthalmia, tuberculosis (TB), sarcoidosis etc.5 We, hereby, describe a case of DUSN who presented with unique features of serous macular detachment with multifocal choroiditis and no visible worm initially, thereby, posing a diagnostic dilemma.
Identifying novel candidates and configurations for human helminth vaccines
Published in Expert Review of Vaccines, 2021
Efforts to generate vaccines against helminths date back 50 years to the development of a dog hookworm vaccine using irradiated infective larvae of Ancylostoma caninum [9,10]. While not a commercial success (as the vaccine did not entirely prevent transmission), this demonstrated that vaccine-induced immunity was possible, and paved the way for a similar irradiated larval vaccine (Huskvac) for lungworm (Dictyocaulus viviparus) in cattle [11]. A separate initiative, also in the veterinary arena, led to the development of a vaccine based on purified intestinal antigens of Haemonchus contortus (the ‘Barber’s Pole’ worm), now marketed as Barbervax [12,13]. Finally, successful recombinant vaccines have been pioneered against cestode tapeworms of livestock [14], now marketed in a number of tropical countries as CysVax (for Taenia solium in pigs) and Hidatil (for Echinococcus granulosus in ruminants).
Diffuse Unilateral Subacute Neuroretinitis Evolving With Submacular Granuloma
Published in Ocular Immunology and Inflammation, 2021
Thiago José Muniz Machado Mazzeo, Nelson Batista Sena, Mario Martins Motta, André Luiz Land Curi
Parasites of different sizes and species have been proposed as the etiologic agent of DUSN, including Ancylostoma caninum, Toxocara canis, and Baylisascaris procyonis. Thus, it is hypothesized that different infectious worms may be considered as the likely cause of a both autommune and toxic form of nematode retinopathy. Because serologic testing is variable, the definitive diagnosis is made when typical clinical characteristics of DUSN are found in conjunction with an intraocular worm. Ancillary tests can assist in the differential diagnosis when the nematode cannot be visualized, such as Optical Coherence Tomography (OCT), Fluorescein angiography and others.3–5