Angiostrongylus costaricensis infection in Martinique, Lesser Antilles, from 2000 to 2017.

Human abdominal angiostrongyliasis (HAA) is a parasitic disease caused by the accidental ingestion of the nematode Angiostrongylus costaricensis in its larval form. Human infection can lead to severe ischemic and inflammatory intestinal lesions, sometimes complicated by life-threatening ileal perforations. Only one case had been reported in Martinique, an Island in the French Antilles, in 1988. We retrospectively reviewed the medical charts of patients diagnosed with abdominal angiostrongyliasis at the University Hospital of Martinique between 2000 and 2017. The objectives of this study were to evaluate the incidence and perform a descriptive analysis of the clinical, biological, radiological, and histopathological features of HAA in Martinique. Two confirmed cases and two probable cases were identified in patients aged from 1 to 21 years during the 18-year period, with an estimated incidence of 0.2 cases per year (0.003 case/year/100.000 inhabitants (IC95% = 0.00-0.05)). All patients presented with abdominal pain associated with high blood eosinophilia (median: 7.24 G/L [min 4.25; max 52.28 G/L]). Two developed ileal perforation and were managed by surgery, with diagnostic confirmation based on histopathological findings on surgical specimens. The other two cases were probable, with serum specimens reactive to Angiostrongylus sp. antigen in the absence of surgery. All cases improved without sequelae. The description of this case series highlights the need to increase awareness of this life-threatening disease in the medical community and to facilitate access to specific diagnostic tools in Martinique. Environmental and epidemiological studies are needed to broaden our knowledge of the burden of this disease.

TITLE: Infections par Angiostrongylus costaricensis à la Martinique, Antilles, de 2000 à 2017. ABSTRACT: L'angiostrongylose abdominale humaine (AAH) est une maladie parasitaire causée par l'ingestion accidentelle du nématode Angiostrongylus costaricensis sous sa forme larvaire. L'infection humaine peut conduire à des lésions intestinales ischémiques et inflammatoires sévères, parfois compliquées par des perforations iléales menaçant le pronostic vital. Un seul cas avait été signalé en Martinique, une île des Antilles françaises, en 1988. Nous avons revu rétrospectivement les dossiers médicaux des patients ayant reçu un diagnostic d'angiostrongylose abdominale au CHU de la Martinique entre 2000 et 2017. Les objectifs de cette étude étaient d'évaluer l'incidence et effectuer une analyse descriptive des caractéristiques cliniques, biologiques, radiologiques et histopathologiques de l'AAH en Martinique. Deux cas confirmés et deux cas probables ont été identifiés chez des patients âgés de 1 à 21 ans au cours de la période de 18 ans, avec une incidence estimée à 0,2 cas par an (0,003 cas / an / 100 000 habitants (IC95% = 0,00 − 0,05)). Tous les patients présentaient une douleur abdominale associée à une éosinophilie sanguine élevée (médiane: 7,24 G/L [min 4,25; max 52,28 G / L]). Deux ont développé une perforation iléale et ont été traités par chirurgie, avec une confirmation diagnostique basée sur les résultats histopathologiques sur des échantillons chirurgicaux. Les deux autres cas étaient probables, avec des échantillons sériques réagissant aux antigènes d'Angiostrongylus sp. en l'absence de chirurgie. Tous les cas se sont améliorés sans séquelles. La description de cette série de cas souligne la nécessité de sensibiliser davantage la communauté médicale à cette maladie potentiellement mortelle et de faciliter l'accès à des outils diagnostiques spécifiques en Martinique. Des études environnementales et épidémiologiques sont nécessaires pour élargir nos connaissances sur cette parasitose.

Schistosome Egg Migration: Mechanisms, Pathogenesis and Host Immune Responses.

Many parasitic worms possess complex and intriguing life cycles, and schistosomes are no exception. To exit the human body and progress to their successive snail host, Schistosoma mansoni eggs must migrate from the mesenteric vessels, across the intestinal wall and into the feces. This process is complex and not always successful. A vast proportion of eggs fail to leave their definite host, instead becoming lodged within intestinal or hepatic tissue, where they can evoke potentially life-threatening pathology. Thus, to maximize the likelihood of successful egg passage whilst minimizing host pathology, intriguing egg exit strategies have evolved. Notably, schistosomes actively exert counter-inflammatory influences on the host immune system, discreetly compromise endothelial and epithelial barriers, and modulate granuloma formation around transiting eggs, which is instrumental to their migration. In this review, we discuss new developments in our understanding of schistosome egg migration, with an emphasis on S. mansoni and the intestine, and outline the host-parasite interactions that are thought to make this process possible. In addition, we explore the potential immune implications of egg penetration and discuss the long-term consequences for the host of unsuccessful egg transit, such as fibrosis, co-infection and cancer development.

Early stages of development of the Taenia solium metacestode in pigs.

In order to identify the early stages of Taenia solium metacestodes, 12 pigs were each fed 100,000 viable eggs and later killed and necropsied at different times after infection. Hematoxylin-eosin (HE) and immunohistochemical techniques (IHCs) were used to identify onchospheres and cysticerci in different tissues. At 2 days postinfection (dpi) structures compatible with onchospheres were found in the lumen of the small intestine, and in the mesenteric blood vessels and lymph nodes. At 4 dpi, these same structures were observed in the small intestine, the liver, and skeletal muscles. Between 6 and 39 dpi, they were found only in skeletal muscles. Between 2 and 6 dpi the postonchospheres were circular and oval shaped and measured between 6 and 34 x 27 microm. From 14 to 39 dpi, well-developed metacestodes 550 x 750 microm were observed. IHCs support the identification of early stages of T. solium.

Lesions in sheep inoculated with Sarcocystis tenella sporocysts from canine feces.

Sarcocystosis was studied in 37 sheep after oral inoculation with 10(4)-5 x 10(7) sporocysts of Sarcocystis tenella from canine feces. Two sheep inoculated with 2.5 x 10(7) and 5 x 10(7) sporocysts became moribund 16 and 19 days post-inoculation (DPI), respectively, due to occlusion of arteries of gut and mesentery by first generation meronts. Sheep inoculated with 10(7) sporocysts remained clinically normal until 21 DPI and those inoculated with 10(5)-10(6) became ill 24-28 DPI due to anemia coincident with maturation of second generation meronts. Inflammation, hepatitis and myocarditis were the main lesions of acute and subacute ovine sarcocystosis. Inflammation began to subside by the time (75 DPI) sarcocysts matured. Sarcocystis-induced encephalitis was distinguished from naturally occurring myelomalacia in sheep caused by an unidentified sporozoan.