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What is gnatostomiasis?

Gnatostomiasis is a zoonosis (a infection transmitted from animals) caused by larvae of a nematode (unsegmented roundworm). The most common cause is Gnathostoma spinigerum. Other species include G. hispidum.

Cutaneous Gnatostomiasis is known by several names around the world, including:

  • Yangtze River edema
  • Shanghai Rheumatism
  • Tuao Chid
  • Panniculitis nodular Immigration law.

Who gets gnatostomiasis?

Gnatostomiasis is endemic in countries where food is eaten raw or undercooked. Affected regions include Southeast Asia, Japan, Latin America, China, India, and Africa. The first Australian case was confirmed in 2011 in Western Australia.

Gnatostomiasis is rare. However, the diagnosis should be considered in people with skin lesions and eosinophilia who have recently traveled in endemic countries.

What causes gnatostomiasis?

Gnatostomiasis is caused by ingesting larvae in poorly cooked food, such as fish, chicken, snakes, and frogs. Sushi generally does not pose a risk of gnathostomiasis, as more expensive saltwater fish do not carry larvae.

In humans, intermittent symptoms appear when late third stage larvae migrate through the tissues. Larvae cannot reach sexual maturity in a human being. host.

What are the clinical characteristics of gnatostomiasis?

Generalized Symptoms can develop within 24-48 hours after consuming the larvae. Such symptoms include:

  • Fever and discomfort
  • Urticaria
  • Gastrointestinal symptoms: diarrhea, nausea, vomiting, anorexia, and right upper quadrant (epigastric or pain) abdominal pain / epigastric
  • These symptoms can last 2 to 3 weeks as the larva migrates through the stomach wall, intestines, or liver.

Cutaneous gnatostomiasis

Cutaneous gnatostomiasis appears as linear no-bites edema.

  • Can be erythematous, pruritus or painful
  • It is usually lonely. However, multiple injuries have been reported.
  • The most common sites are the trunk or upper extremities.
  • The larvae leave tracking marks (known as deep larva migrans) and subcutaneous hemorrhages

Injuries seen on the face are associated with spread to the central nervous system or eyes.

Visceral gnatostomiasis

Visceral disease is due to the migration of gnatostomiasis larvae within the body.

Pulmonary symptoms

  • Cough
  • Pleuritic pain in the chest
  • Haemoptysis
  • Pneumothorax
  • Lobar consolidation or collapse

Gastrointestinal symptoms

  • Sharp pains
  • May be confused with appendicitis or intestinal obstruction

Genitourinary symptoms

  • Rare
  • Hematuria
  • Passage of larvae in the urine.
  • Hematospermia
  • Vaginal bleeding

Ocular symptoms

  • Uveitis
  • Iritis
  • Glaucoma
  • Retinal scars
  • Retinal detachment

Atrial symptoms

  • Mastoiditis
  • Sensorineural hearing loss

The central nervous system (CNS)

  • Potentially life threatening
  • Subarachnoid hemorrhage
  • Eat
  • Brain stem involvement: respiratory failure
  • Eosinophilic meningitis.

CNS disease can present as a disease that gets progressively worse over several days. Symptoms include:

  • Incontinence
  • Loss of sensation
  • Headaches
  • Root pain in the extremities.
  • Weakness or partial paralysis limb

How is gnatostomiasis diagnosed?

Gnatostomiasis is diagnosed by serology in blood or cerebrospinal fluid (CSF) when the CNS is involved.

It can be suspected in the presence of significant blood or CSF eosinophilia (up to 50% of total white blood cell count). Note that eosinophilia disappears in chronic disease when larvae enter subcutaneous tissues.

Magnetic resonance imaging (Magnetic resonance) shows diffuse spinal cable magnification and areas of higher signal strength.

A skin biopsy can show characteristic features. See also gnatostomiasis. pathology.

What is the treatment for gnatostomiasis?

Gnatostomiasis larvae on the skin are removed surgically.

Medical treatment may include ivermectin or albendazole.

What is the result of gnatostomiasis?

If cutaneous or visceral gnatostomiasis is not treated, the larvae can continue to cause intermittent symptoms until they die, which can last up to 12 years. The patient is considered disease free if asymptomatic for 12 months after treatment, eosinophilia resolved and ELISA levels decreased.

Relapse it can occur up to 7 months after treatment, requiring retreatment and close follow-up. There is a high mortality rate for patients with CNS involvement.