Halicephalobus gingivalis (H.deletrix) in the brain of a horse

Abstract

III Halicephalobus gingivalis (H.deletrix) no cérebro de um eqüino ABSTRACT A 10-year-old Mangalarga gelding with rhabditiform nematode infection in the brain

First description of a fatal equine infection with Halicephalobus gingivalis in Portugal. Relevance for public health

“…Regarding preferred locations for the parasite, the brain and the kidney are generally described as the most significantly affected organs, followed by the oral and nasal cavities, lymph nodes, spinal cord, adrenal glands, heart, stomach, liver, peripheral nerve ganglia, bones and joints (Rames et al 1995;Isaza et al 2000;Johnson et al 2001;Pearce et al 2001;Bryant et al 2006;Eydal et al 2012). Larvae and eggs or zygotes are most commonly found in the infected tissues, with rare adults present (Anderson et al 1998;Br€ ojer et al 2000;Isaza et al 2000;Johnson et al 2001;Bryant et al 2006;Akagami et al 2007;Vasconcelos et al 2007;Muller et al 2008). Adult forms are invariably females described with a typical rhabditoid oesophagus, with a body, isthmus and a dilated bulb and only one egg in the uterus.…”

“…; Vasconcelos et al . ). In a number of cases, the horses are reported to have suffered a prior injury to the mouth, eyes and skin (Rames et al .…”

“…H. gingivalis, previously referred to as Micronema deletrix or H. deletrix, is a small 250-450 lm by 15-25 lm, free-living saprophytic rhabditid nematode, represented only by females with a typical rhabditoid oesophagus and one egg in the uterus, capable of infecting vertebrates (Chitwood & Lichtenfels 1972;Johnson et al 2001;Vasconcelos et al 2007;Papadi et al 2013;Eberhard 2014). This opportunistic parasite is commonly found in soil, manure, foul water or decaying humus (Johnson et al 2001;Nadler et al 2003).…”

“…This opportunistic parasite is commonly found in soil, manure, foul water or decaying humus (Johnson et al 2001;Nadler et al 2003). There are so far, <100 cases of halicephalobosis described in literature, mostly in horses (Rames et al 1995;Anderson et al 1998;Br€ ojer et al 2000;Johnson et al 2001;Nadler et al 2003;Bryant et al 2006;Vasconcelos et al 2007) -including ponies (Akagami et al 2007) -, but also in zebras (Isaza et al 2000), cattle (Enemark et al 2016) and humans (Papadi et al 2013;Anwar et al 2015;Lim et al 2015;Monoranu et al 2015). H. gingivalis infection in horses has been reported in five continents, usually involving a wide range of ages (from colts to aging adults) and breeds, leading almost invariably, to a fatal outcome (Anderson et al 1998;Lim et al 2015;Monoranu et al 2015).…”

“…In Europe, the disease is reported in several countries, such as the United Kingdom, Belgium, Italy, Denmark, Spain, Iceland and Romania (Rames et al 1995;Anderson et al 1998;Br€ ojer et al 2000;Johnson et al 2001;Bryant et al 2006;Akagami et al 2007;Eydal et al 2012;Gracia-Calvo et al 2014;Jung et al 2014;Lim et al 2015;Taulescu et al 2015;Pintore et al 2017). Owners seek veterinary assistance mostly due to unexpected and unexplained onset of neurological symptoms, such as anorexia, ataxia, urinary incontinence, blindness, decreased menace and tonal reflexes, tremors and aggressiveness (Rames et al 1995;Anderson et al 1998;Br€ ojer et al 2000;Johnson et al 2001;Bryant et al 2006;Akagami et al 2007;Vasconcelos et al 2007). In a number of cases, the horses are reported to have suffered a prior injury to the mouth, eyes and skin (Rames et al 1995;Anderson et al 1998;Br€ ojer et al 2000;Isaza et al 2000;Eydal et al 2012).…”