Angiostrongyliasis

What it is

From: Orphanet

A foodborne zoonotic disease, endemic to Southeast Asia and the Pacific Islands, caused by the rat lungworm Angiostrongylus cantonensis and that is acquired by the ingestion of the infective larvae on vegetables or in raw or undercooked snails, slugs, land crabs, freshwater shrimps, frogs and lizards. The main feature is eosinophilic meningitis, with clinical manifestations including fever, headache, malaise, fatigue, vomiting, rhinorrhea, blurred vision, diplopia, cough, stiff neck, enteritis, constipation and paraesthesia due to the movement of the worms from the intestines to the lungs, central nervous system and eyes. In severe cases without treatment, coma and death can occur.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

CSF pleocytosis · Very frequent (99-80%)

An increased white blood cell count in the cerebrospinal fluid.

Headache · Very frequent (99-80%)

Cephalgia, or pain sensed in various parts of the head, not confined to the area of distribution of any nerve.

Hypereosinophilia · Very frequent (99-80%)

Severe increase in circulating eosinophils, usually characterized as more than 1500 eosinophils per microlitre.

Abdominal pain · Frequent (79-30%)

An unpleasant sensation characterized by physical discomfort (such as pricking, throbbing, or aching) and perceived to originate in the abdomen.

Arthralgia · Frequent (79-30%)

Joint pain.

Brain imaging abnormality · Frequent (79-30%)

An anomaly of metabolism or structure of the brain identified by imaging.

Constipation · Frequent (79-30%)

Infrequent or difficult evacuation of feces.

Diplopia · Frequent (79-30%)

Diplopia is a condition in which a single object is perceived as two images, it is also known as double vision.

Excessive daytime somnolence · Frequent (79-30%)

A state of abnormally strong desire for sleep during the daytime.

Fatigue · Frequent (79-30%)

A subjective feeling of tiredness characterized by a lack of energy and motivation.

Fever · Frequent (79-30%)

Body temperature elevated above the normal range.

Gastrointestinal eosinophilia · Frequent (79-30%)

Eosinophilic infiltration of one or more gastrointestinal organs. Gastrointestinal eosinophilia is a broad term for abnormal eosinophil accumulation in the GI tract, involving many different disease identities. These diseases include primary eosinophil associated gastrointestinal diseases, gastrointestinal eosinophilia in HES and all gastrointestinal eosinophilic states associated with known causes. Each of these diseases has its unique features but there is no absolute boundary between them.

Increased intracranial pressure · Frequent (79-30%)

An increase of the pressure inside the cranium (skull) and thereby in the brain tissue and cerebrospinal fluid.

Irritability · Frequent (79-30%)

An emotional state characterized by negative feelings of heightened frustration, annoyance, or feeling upset, often triggered by internal factors (e.g., fatigue, hunger, unfulfilled desires) or external factors (e.g., social or environmental challenges). Irritability may be unpredictable, and is accompanied by a lowered threshold for emotional reactivity and observable features (speech, facial expressions, or psychomotor activity).

Other findings in the same source

From: Orphanet

Additional reported features include Meningitis (Frequent (79-30%)); Myalgia (Frequent (79-30%)); Paresthesia (Frequent (79-30%)); Poor appetite (Frequent (79-30%)); Projectile vomiting (Frequent (79-30%)); Stiff neck (Frequent (79-30%)); Unusual CNS infection (Frequent (79-30%)); Vomiting (Frequent (79-30%)); Blurred vision (Occasional (29-5%)); Cerebral edema (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

All ages

Inheritance in the source

From: Orphanet

Not applicable

Which doctor should you see?

The suggested department for discussing Angiostrongyliasis is Infectious Diseases, with a general physician / infectious disease specialist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Which exposure or organism is suspected, and what evidence would confirm it?
• Are precautions, vaccination or advice for close contacts relevant to this infection?
• What should happen if symptoms worsen or do not improve as expected?

Treatment discussions and follow-up

Where the source describes treatments, these are an overview of possible care, not a prescription for an individual. Ask which option applies to the confirmed diagnosis, what benefit is expected, what adverse effects to watch for and how progress will be assessed. Availability, approvals and local practice can differ from the country described in the source.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.