Trichinella larvae bury themselves inside muscle tissue rather than remain in the intestine as in other roundworm infections, so stool sample tests don't often show evidence of the parasite. The initial diagnosis relies on the classic signs and symptoms — swelling around the eyes, muscle inflammation and fever.
To confirm the diagnosis, your doctor might use these tests:
- Blood tests. Your doctor may take a blood sample and test it for signs suggesting trichinosis — an increase in the number of a certain type of white blood cell (eosinophils) or the formation of antibodies against the parasite after several weeks.
- Muscle biopsy. While the blood test typically is enough to establish a diagnosis, your doctor might also recommend a muscle biopsy. A small piece of muscle is removed and examined under a microscope to look for trichinella larvae.
Trichinosis usually isn't serious and often gets better on its own, usually within a few months. However, fatigue, mild pain, weakness and diarrhea may linger for months or years. Symptomatic infections may respond to treatment with medication.
Anti-parasitic medication. Anti-parasitic (anthelminthic) medication is the first line of treatment against trichinosis. If the trichinella parasite is discovered early, in the intestinal phase, albendazole (Albenza) or mebendazole can be effective in eliminating the intestinal worms and larvae. You may have mild gastrointestinal side effects during the course of treatment.
If the disease is discovered after the larvae bury themselves in tissues, the benefit of anti-parasitic medications is less certain. Your doctor might prescribe one if you have central nervous system, cardiac or respiratory problems as a result of the invasion
- Pain relievers. After muscle invasion, pain relievers may be given for muscle aches. Eventually, the larvae cysts in your muscles tend to calcify, resulting in destruction of the larvae and the end of muscle aches and fatigue.
- Corticosteroids. Some cases of trichinosis cause allergic reactions when the parasite enters muscle tissue or when dead or dying larvae release chemicals in your muscle tissue. Your doctor might prescribe a corticosteroid to control inflammation during larval migration.
Preparing for your appointment
You're likely to start by seeing your family doctor or a general practitioner. In some cases, you may be referred to an infectious disease specialist.
Here's some information to help you prepare for your appointment.
What you can do
- Be aware of pre-appointment restrictions. When you make the appointment, ask if there's anything you need to do in advance, such as restrict your diet.
- Write down your symptoms, including any that seem unrelated to the reason for which you scheduled the appointment.
- Write down key personal information, including major stresses or recent life changes.
- List all medications, vitamins and supplements you take.
- Take a family member or friend along, if possible. Someone who accompanies you can help you remember the information you get.
- Write down questions to ask your doctor.
Preparing a list of questions will help you make the most of your time with your doctor. For trichinosis, some basic questions to ask your doctor include:
- What is likely causing my symptoms or condition?
- What are other possible causes?
- What tests do I need?
- Is my condition likely temporary or chronic?
- What is the best course of action?
- What are the alternatives to the primary approach you're suggesting?
- I have these other health conditions. How can I manage them together?
- Is there a generic alternative to the medicine you're prescribing?
- Are there brochures or other printed material I can take? What websites do you recommend?
Don't hesitate to ask other questions.
What to expect from your doctor
Your doctor is likely to ask you a number of questions, including:
- When did your symptoms begin?
- Have you eaten raw or rare or unusual meat such as game lately?
- Have your symptoms been continuous or occasional?
- How severe are your symptoms?
- What, if anything, improves your symptoms?
- What, if anything, worsens your symptoms?
May 18, 2018
- Trichinosis (trichiniasis). Merck Manual Professional Version. https://www.merckmanuals.com/professional/infectious-diseases/nematodes-roundworms/trichinosis. Accessed Feb. 17, 2018.
- Trichinellosis FAQs. Centers for Disease Control and Prevention. https://www.cdc.gov/parasites/trichinellosis/gen_info/faqs.html. Accessed Feb. 17, 2018.
- Weller PF, et al. Trichinellosis. https://www.uptodate.com/contents/search. Accessed Feb. 17, 2018.