Parasitosis caused by ingestion of under-cooked meat containing Trichinella species larvae.
The most important reservoir is the domestic pig, although a variety of other animals, including horses and wild carnivores, can be the source of infection.
Bi-phasic disease characterised by a gastrointestinal (enteric) phase followed by a systemic (parenteral) phase.
The intestinal phase occurs within a few days of ingestion of the parasite and manifests with gastrointestinal symptoms, such as abdominal pain, nausea, vomiting, and diarrhoea.
The systemic phase most commonly manifests with fever, eosinophilic myositis, myalgia, and peri-orbital oedema, although it may also cause myocarditis and encephalitis.
Although the disease severity can range from mild to lethal, a full recovery within 6 weeks to 6 months is the most common course.
Treatment is with albendazole or mebendazole and, occasionally, prednisolone.
Appropriate cooking of meat is key to prevention of the disease.
Trichinellosis is a parasitosis caused by the ingestion of raw or under-cooked meat (usually pork) containing Trichinella species cysts. It is a bi-phasic disease characterised by a gastrointestinal (enteric) phase followed by a systemic (parenteral) phase. The intestinal phase occurs within a few days of ingesting the parasite and manifests with gastrointestinal symptoms, such as abdominal pain, nausea, vomiting, and diarrhoea. After the first week, larvae released from the cysts become adult worms and mate. The female parasites then release newborn larvae that disseminate, leading to the systemic phase. This phase manifests with fever, eosinophilic myositis, myalgia, and peri-orbital oedema. Rarely, it may also cause myocarditis or encephalitis.
History and exam
Key diagnostic factors
- consumption of raw or under-cooked meat
- sick contacts
- myalgia and myositis
- peri-orbital/facial oedema
- conjunctivitis and sub-conjunctival haemorrhages
Other diagnostic factors
- subungual and retinal splinter haemorrhages
- other ocular features
- nausea and vomiting
- abdominal pain
- maculopapular rash
- other cutaneous features
- paralysis-like state
- other neurological features
- consumption of raw or under-cooked pork
- consumption of raw or under-cooked horse or other domestic animal meat
- consumption of raw or under-cooked wild game meat
- consumption of raw or under-cooked reptile meat
1st investigations to order
- FBC with differential
- creatine kinase and other muscle enzymes
- serum potassium
- serum albumin
- serum IgE
Investigations to consider
- antibody serology
- muscle biopsy
- serum creatinine and creatinine clearance
- serum transaminases
- MRI or CT brain
- cerebrospinal fluid analysis
- serum troponin
- 2-dimensional echocardiography
- circulating antigens
- DNA amplification
Miguel G. Madariaga, MD, MSc, FACP
Infectious Diseases Consultant
Naples Community Hospital
MGM declares that he has no competing interests.
Fabrizio Bruschi, MD
Professor of Parasitology
Department of Experimental Pathology BMIE
Faculty of Medicine and Surgery
University of Pisa
FB is an author of a number of references cited in this topic.
Jean Dupouy-Camet, MD, PhD
Chef du Service de Parasitologie-Mycologie
JDC is an author of a number of references cited in this topic. JDC declares that he has no competing interests.
Christopher D. Huston, MD
Division of Infectious Diseases
Department of Medicine
University of Vermont College of Medicine
CDH declares that he has no competing interests.
- Bacterial gastroenteritis
- Respiratory or gastrointestinal viral infections
- FAO/WHO/OIE guidelines for the surveillance, management, prevention and control of trichinellosis
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