Three successive cases of enteric anisakiasis

Clinical and Endoscopic Features of Colonic Anisakiasis in Korea

To analyze the clinical and endoscopic features of colonic anisakiasis. A retrospective chart review of 20 patients with colonic anisakiasis, who were diagnosed by colonoscopy at 8 hospitals between January 2002 and December 2011, was performed. Patients’ mean age was 53.6±10.74 years. Seventy percent patients were men. Acute abdominal pain was a common symptom that mostly developed within 48 hr after the ingestion of raw fish, and which lasted for 1–28 days. Sixty percent patients had ingested raw fish before the diagnosis of colonic anisakiasis and 40% patients were incidentally found to have colonic anisakiasis during the screening colonoscopies. Leukocytosis and eosinophilia were each found in 20% of the patients. In all patients who underwent colonoscopy, the worms were removed with biopsy forceps, except in 1 case, and a definite diagnosis of anisakiasis was made. In some cases of colonic anisakiasis, colonoscopy may be helpful in the diagnosis and treatment to avoid surgical intervention.

Increased number of eosinophils in ascites is associated with intestinal anisakidosis

The aim of this study was to evaluate the association between eosinophils in ascites and the diagnosis of intestinal anisakidosis in patients with peritoneal signs on physical examination. We reviewed retrospectively 16 patients diagnosed with intestinal anisakidosis, evaluated between 2012 and 2015. All patients had ingested raw anchovies. The analysis of ascites fluid in ten of these patients was compared with that of 15 patients with ascites and other abdominal pathology (except liver cirrhosis). All patients had an increased number of white blood cells in the ascites fluid. The eosinophil count was significantly higher in patients with intestinal anisakidosis (P < 0.01). All patients had a good outcome. Increased eosinophils in ascites fluid is strongly associated with the diagnosis of intestinal anisakidosis.

Molecular Epidemiology of Anisakis and Anisakiasis: An Ecological and Evolutionary Road Map

This review addresses the biodiversity, biology, distribution, ecology, epidemiology, and consumer health significance of the so far known species of Anisakis, both in their natural hosts and in human accidental host populations, worldwide. These key aspects of the Anisakis species' biology are highlighted, since we consider them as main driving forces behind which most of the research in this field has been carried out over the past decade. From a public health perspective, the human disease caused by Anisakis species (anisakiasis) appears to be considerably underreported and underestimated in many countries or regions around the globe. Indeed, when considering the importance of marine fish species as part of the everyday diet in many coastal communities around the globe, there still exist significant knowledge gaps as to local epidemiological and ecological drivers of the transmission of Anisakis spp. to humans. We further identify some key knowledge gaps related to Anisakis species epidemiology in both natural and accidental hosts, to be filled in light of new 'omic' technologies yet to be fully developed. Moreover, we suggest that future Anisakis research takes a 'holistic' approach by integrating genetic, ecological, immunobiological, and environmental factors, thus allowing proper assessment of the epidemiology of Anisakis spp. in their natural hosts, in human populations, and in the marine ecosystem, in both space and time.

Intestinal Anisakiasis Treated Successfully with Prednisolone and Olopatadine Hydrochloride

The clinical characteristic of gastrointestinal anisakiasis is severe abdominal pain after eating raw fish. Intestinal anisakiasis is more uncommon than gastric anisakiasis. Most patients with intestinal anisakiasis need hospitalization because anisakiasis can cause intestinal obstruction, ileus, peritonitis or intestinal perforation. We report a case of intestinal anisakiasis. A 43-year-old woman presented with symptoms of intermittent abdominal pain 2 days after eating raw fish. Her brother had eaten the same food and had been suffering from gastric anisakiasis. Abdominal ultrasonography in this patient showed localized jejunal wall thickening with dilated lumen of proximal jejunum and ascites. According to the clinical course and examinations, she was diagnosed with intestinal anisakiasis. Administration of prednisolone 5 mg/day and olopatadine hydrochloride 10 mg/day improved her symptoms quickly without hospitalization. Prednisolone was administered for 10 days, and olopatadine hydrochloride was administered for a total of 6 weeks according to ultrasonographic findings. Six months after the treatment, the abdominal ultrasonography demonstrated normal findings. This case demonstrates that ultrasonography was quite useful for the diagnosis and surveillance of intestinal anisakiasis. Furthermore, treatment with corticosteroid and an antiallergic agent could be an option for patients with intestinal anisakiasis.

Common Symptoms from an Uncommon Infection: Gastrointestinal Anisakiasis

Clinicians can be forgiven for thinking of anisakiasis as a rare condition low in the differential diagnosis of abdominal pain. Gastrointestinal anisakiasis is a zoonotic parasitic disease caused by consumption of raw or undercooked seafood infected with nematodes of the genus Anisakis. Even though the reported cases indicate that this is a rare disease, the true incidence of the disease could be potentially higher than what is reported in the literature as cases can go undiagnosed. Diagnosis and treatment of gastric anisakiasis are made by a compatible dietary history, direct visualization, and removal of the larvae via gastroscopy. Serologic testing and imaging studies are useful in the diagnosis of intestinal anisakiasis and conservative management should be considered. This disease may mimic other diseases and lead to unnecessary surgery. This emphasizes the importance of suspecting gastrointestinal anisakiasis by history taking and by other diagnostic modalities.

Sonographic diagnosis of intestinal anisakiasis presenting as small bowel obstruction

BACKGROUND

To evaluate the accuracy of ultrasonography (US) in the diagnosis of intestinal anisakiasis presenting as small bowel obstruction.

METHODS

We retrospectively reviewed the clinical features, US examinations, and CT scans of seven patients with intestinal anisakiasis presenting as small bowel obstruction. We compared the performances of US and CT in demonstrating peritoneal fluid, small bowel dilatation, and segmental edema of Kerckring's folds.

RESULTS

All patients presented with a history of ingesting raw saltwater fish or squid less than 2 days prior to presentation at the emergency department and had significant levels of Anisakis-specific IgE. Both US and CT revealed small bowel obstruction, with dilated small bowel in all patients and accumulations of free peritoneal fluid in six patients. CT showed segmental wall thickening and luminal narrowing with submucosal edema distal to the distended small bowel; US did so in four patients.

CONCLUSIONS

Although US was inferior to CT in demonstrating the segmental intestinal edema causing small bowel obstruction, it can be applied in suspected cases of intestinal anisakiasis presenting as small bowel obstruction, particularly where CT is unavailable or there are concerns about radiation exposure.

Acute Small-Bowel Obstruction From Intestinal Anisakiasis After the Ingestion of Raw Clams; Documenting a New Method of Marine-to-Human Parasitic Transmission

Enteric anisakiasis is a known parasitic infection. To date, human infection has been reported as resulting from the inadvertent ingestion of the anisakis larvae when eating raw/undercooked fish, squid, or eel. We present a first reported case of intestinal obstruction caused by anisakiasis, after the ingestion of raw clams.

Intestinal anisakidosis: histopathological findings and differential diagnosis

Anisakidosis is a human zoonotic disease caused by the ingestion of raw or undercooked or not adequately salted, pickled, or smoked fish containing larval nematodes of the Anisakis species. The incidence of this infection is higher in geographical zones with traditional consumption of raw fish. However, in the last years, prevalence raised in low risk zones due to the increase popularity of Asian cuisine. According to where the larvae settle in the gastrointestinal tract, anisakidosis may have different clinical symptoms. In particular, intestinal anisakidosis may mimic several surgical conditions, including appendicitis, ileitis, diverticulitis or inflammatory bowel disease. For this reason, diagnosis is often histopathological. In the present paper, we describe the clinico-pathological findings of six novel cases of intestinal anisakidosis occurred in southern Italy, and provide clues for the differential diagnosis toward Crohn's disease and eosinophilic enteritis, which have similar histopathological characteristics. Awareness of the existence of intestinal anisakidosis may facilitate its recognition and correct diagnosis, which is of fundamental importance for appropriate therapeutic approach.

Small intestinal obstruction caused by anisakiasis

Small intestinal anisakiasis is a rare disease that is very difficult to diagnose, and its initial diagnosis is often surgical. However, it is typically a benign disease that resolves with conservative treatment, and unnecessary surgery can be avoided if it is appropriately diagnosed. This case report is an example of small intestinal obstruction caused by anisakiasis that resolved with conservative treatment. A 63-year-old man admitted to our department with acute abdominal pain. A history of raw fish (sushi) ingestion was recorded. Abdominal CT demonstrated small intestinal dilatation with wall thickening and contrast enhancement. Ascitic fluid was found on the liver surface and in the Douglas pouch. His IgE (RIST) was elevated, and he tested positive for the anti-Anisakis antibodies IgG and IgA. Small intestinal obstruction by anisakiasis was highly suspected and conservative treatment was performed, ileus tube, fasting, and fluid replacement. Symptoms quickly resolved, and he was discharged on the seventh day of admission. Small intestinal anisakiasis is a relatively uncommon disease, the diagnosis of which may be difficult. Because it is a self-limiting disease that usually resolves in 1-2 weeks, a conservative approach is advisable to avoid unnecessary surgery.

Intestinal anisakiasis as a rare cause of small bowel obstruction

Anisakiasis, a parasitic infection by larvae of the nematode Anisakis found in raw or undercooked saltwater fish, mostly involves stomach but rarely small intestine. We report a rare case of a 61-year-old man who presented with abdominal pain and developed small bowel obstruction caused by intestinal anisakiasis. Abdominal computed tomography revealed segmental edema of the intestinal wall with proximal dilatation. The patient underwent urgent laparotomy because strangulated small bowel obstruction was suspected. A localized portion of the intestine around jejunoileal junction was found to be erythematous, edematous, and hardened, which was resected. The resected specimen showed a linear whitish worm, Anisakis simplex, penetrating into the intestinal mucosa. It is often clinically challenging to consider intestinal anisakiasis in the differential diagnosis because of its nonspecific abdominal symptoms and findings. Although gastrointestinal anisakiasis is still rare in the United States, the incidence is expected to rise given the growing popularity of Japanese cuisine such as sushi or sashimi. Anisakiasis should be considered as one of the differential diagnoses in patients with nonspecific abdominal symptoms after consumption of raw or undercooked fish.

Unusual cause of small intestine obstruction in a child

Introduction

Anisakiasis is caused by human infection by the anisakis larvae, a marine nematode found in undercooked or raw fish. Infection with the parasite Anisakis simplex is common in Japan and northern European countries. With the increased popularity of eating sushi and raw fish infection with anisakis is expected to rise.

Case presentation

We present the case of a 14-year-old boy who had eaten sushi 3 days before the onset of symptoms and had small bowel obstruction caused by enteric anisakiasis. To the best of our knowledge this is the first reported case of intestinal anisakiasis presenting as a bowel obstruction in a child.

Conclusion

Enteric anisakiasis is very rare, and its diagnosis is usually made after laparotomy. Nevertheless, when signs of acute abdomen develop after the ingestion of raw fish, such as sushi or sashimi, the possibility of enteric anisakiasis should be considered.

Comparison of the clinical characteristics of patients with small bowel and gastric anisakiasis in jeju island

Background/Aims

Anisakiasis is frequent in Jeju Island because of the people's habit of ingesting raw fish. This study evaluated the clinical characteristics of patients with small bowel anisakiasis and compared them with those of patients with gastric anisakiasis.

Methods

We retrospectively reviewed the medical records of 109 patients diagnosed with anisakiasis between May 2003 and November 2011.

Results

Of the 109 patients diagnosed with anisakiasis, those with suspicious anisakiasis (n=38) or possible anisakiasis (n=12) were excluded. The age and gender distributions did not differ between patients with small bowel anisakiasis (n=30; age, 45±13 years) and those with gastric anisakiasis (n=29; age, 46±10 years). The mean duration of hospitalization was 5.4±4.3 days for patients with small bowel anisakiasis and 0.5±1.7 days for patients with gastric anisakiasis. Small bowel anisakiasis was accompanied by leukocytosis (76.7% vs 25.5%, p=0.003) and elevated C-reactive protein levels (3.4±3.2 mg/dL vs 0.5±0.3 mg/dL, p=0.009). Contrast-enhanced abdominopelvic computed tomography showed small bowel wall thickening with dilatation in 93.3% (28/30) of patients and a small amount of ascites in 80.0% (24/30) of patients with small bowel anisakiasis.

Conclusions

Compared with gastric anisakiasis patients, small bowel anisakiasis patients had a longer hospitalization time, higher inflammatory marker levels, and small bowel wall thickening with ascites.

Use of negative binomial distribution to describe the presence of Anisakis in Thyrsites atun

Nematodes of the genus Anisakis have marine fishes as intermediate hosts. One of these hosts is Thyrsites atun, an important fishery resource in Chile between 38 and 41° S. This paper describes the frequency and number of Anisakis nematodes in the internal organs of Thyrsites atun. An analysis based on spatial distribution models showed that the parasites tend to be clustered. The variation in the number of parasites per host could be described by the negative binomial distribution. The maximum observed number of parasites was nine parasites per host. The environmental and zoonotic aspects of the study are also discussed.

Antigenicity and viability of Anisakis larvae infesting hake heated at different time-temperature conditions

Heat treatments (40 to 94 degrees Celsius, 30 s to 60 min) were applied to different batches of Anisakis simplex L3 larvae isolated from hake ovaries and viscera to study the effect of heat on the viability of the larvae measured as mobility, emission of fluorescence under UV light, and changes in color after staining with specific dyes, and on A. simplex antigenic proteins. The aim was to determine the lowest time-temperature conditions needed to kill the larvae to avoid anisakiasis in consumers, and to evaluate whether high temperature modifies the antigenicity of A. simplex extracts. Heating at 60 degrees Celsius for 10 min (recommended by some authors) was considered unsafe, as differences in viability between batches were found, with some larvae presenting spontaneous movements in one batch. At higher temperatures (> or = 70 degrees Celsius for > or = 1 min), no movement of the larvae was observed. Antigenic protein Ani s 4 and A. simplex crude antigens were detected in the larvae heated at 94 + or - 1 degrees Celsius for 3 min. This indicates that allergic symptoms could be provoked in previously sensitized consumers, even if the larvae were killed by heat treatment.

Anisakis pegreffi etiological agent of gastric infections in two Italian women

Two cases of gastric anisakiasis have been documented in two Italian women who had consumed raw anchovies (Engraulis encrasicolus). The first patient was a 49-year-old woman presenting with epigastric pain and bloody vomiting after ingestion of marinated (vinegar) raw anchovies. During the esophagogastroduodenoscopy (EGDS) a white color worm was detected and extracted from cardia by means of biopsy forceps. The second patient was a 59-year-old woman with irritable bowel syndrome and gastritis, who underwent to periodical EGDSs. In the course of the last EGDS, a white color round worm on antrum and a small polyp on the fundus of the stomach were observed. The two nematodes have been identified as L3 larvae of the genus Anisakis by a light microscope, and as Anisakis pegreffi by polymerase chain reaction-restriction fragment length polymorphism. The molecular identification of the etiological agent at the species level allows to identify what Anisakidae species play a zoonotic role and which are the fish host species.

Anisakis antigens detected in fish muscle infested with Anisakis simplex L3

Anisakis simplex is a fish parasite that is a public health risk to those consuming raw or poorly cooked marine fish and cephalopods because of the possibility of becoming infested with live larvae. In humans, penetration of the larvae into the gastrointestinal track can cause acute and chronic symptoms and allergic anisakiasis. Excretion and secretion products released by the larvae are thought to play a role in migration through the tissues and induce an immunoglobulin E-mediated immune response. The aim of this preliminary study was to detect parasite antigens and allergens in fish tissues surrounding the migrating larvae. Hake and anchovy fillets were artificially parasitized with Anisakis larvae and stored in chilled conditions for 5 days. Larvae were evaluated for fluorescence, fish muscle tissue was examined with transmission electron microscopy, and immunohistochemical reactions of two rabbit polyclonal antisera against a parasite crude extract and the allergen Ani s 4 were recorded. Larvae immediately migrated into the fish muscle, and no emission of bluish fluorescence was observed. Fish muscle areas in contact with the parasite showed disruptions in the structure and inclusion of granules within sarcomeres. Both parasite antigens and the Ani s 4 allergen were located in areas close to the larvae and where sarcomere structure was preserved. These findings indicate that parasite antigens and allergens are dispersed into the muscle and might cause allergic symptoms such as dyspnea, vomiting, diarrhea, urticaria, angioedema, or anaphylaxis in some individuals sensitive to A. simplex.