Home » Skin Conditions » Cutaneous Larva Migrans

Cutaneous Larva Migrans

Cutaneous larva migrans is a type of dermatitis that occurs in people who have traveled to tropical and subtropical geographical areas. However, because more and more people travel in different areas on the globe, the infection is no longer confined to these areas. The skin presents an eruption that is accompanied by redness and intense pruritus. What happens is that the larvae of different parasites penetrate the skin and migrate from one areas of the body to the other. The eggs of the parasite are passed from the feces of animals into the soil and then the larvae start searching for a new host.

The infection with these larvae often happens when there is a breakdown in the skin, such as a cut or abrasion. However, the larvae can penetrate through the hair follicle and even through intact skin. Migration begins several days after the cutaneous penetration has occurred. This condition is more often encountered in animals and humans are only accidental hosts. This is a benign condition and it is strictly limited to the area of infection. The most disturbing symptom of cutaneous larva migrans is the intense itchiness. There is no gender prevalence and, when it comes to the age, it seems that children are more often affected than adults.

Symptoms of Cutaneous Larva Migrans

These are the most common symptoms of cutaneous larva migrans:

Tingling sensation
- This appears half an hour after the skin penetration
- It may also be described as a prickling sensation
- There are also cases where the onset is late
Intense itchiness
The penetrated area is red
Lesions might form a straight line or even a serpiginous tunnel; when a tunnel is formed, it is a little bit elevated
Continuous advancement of the lesions (line or tunnel)
Lesions in the form of papules or vesicles
When vesicles form on the skin, these are filled with serous liquid
Systemic involvement:
- Peripheral eosinophilia (Loeffler syndrome)
- Migratory pulmonary infiltrates
- Increased immunoglobulin E (IgE) levels
Areas that are most affected include:
- Lower extremities
- Dorsum of the feet
- Interdigital space of the toes
- Ano-genital region
- Buttocks
- Hands
- Knees
Secondary infections can appear due to the excessive scratching

What are the Causes of Cutaneous Larva Migrans?

These are the most common parasites that lead to the appearance of cutaneous larva migrans:

Ancylostoma braziliense

Type of hookworm, commonly found in domestic animals
Present in the following geographical areas:
- United States (central and southern)
- Central America
- South America
- Caribbean

Ancylostoma caninum

Type of hookworm, commonly found in dogs
Present in Australia

Uncinaria stenocephala

Type of hookworm, commonly found in dogs
Present in Europe

Bunostomum phlebotomum

Type of hookworm, commonly found in cattle

Other parasites (rare cases):

Ancylostoma ceylonicum – type of hookworm, commonly found in cats and dogs
Ancylostoma tubaeforme – type of hookworm, commonly found in cats
Ancylostoma duodenale – type of hookworm, commonly found in humans, cats and dogs
Necator americanus – type of hookworm, commonly found in humans
Strongyloides papillosus – parasite commonly found in cattle, sheep and goats
Strongyloides westeri – parasite commonly found in horses
Pelodera strongyloides – parasite commonly found in dogs, cows, horses, sheep, guinea pigs and humans.

How is Cutaneous Larva Migrans Diagnosed?

These are the most common methods for the diagnosis of cutaneous larva migrans:

Clinical examination
- Reveals characteristic appearance of the lesions
Travel history
- Patients often declare having traveled in tropical or subtropical areas, performing different activities such as sunbathing or walking barefoot on the sand (exposure to the parasite eggs)
Complete blood count
- Peripheral eosinophilia
- Increased immunoglobulin E (IgE) levels
Skin biopsy
- May identify the actual larva
- Other modifications include:
  - Creation of basal layer tracts
  - Creation of under-the-skin burrows
  - Spongiosis – the epidermal layer of the skin presents vesicles
  - Keratin cells are necrotized
  - The epidermis and the upper layer of the dermis are inflamed and infiltrated with increased levels of eosinophils
Optical coherence tomography
- The larva can be identified in the epidermis
- Recommended for removal purposes

Differential diagnosis can be made with the following medical conditions:

Impetigo
Tinea pedis
Contact dermatitis
Dermatophytoses
Erythema chronicum migrans (commonly associated with Lyme disease)
Photoallergic dermatitis
Scabies

Treatment for Cutaneous Larva Migrans

The treatment is recommended in order to relieve the symptoms (itchiness) and also to treat the secondary infections. Prevention is recommended and people traveling to tropical and subtropical areas are indicated to avoid walking barefoot on different types of soil (because of the potential contamination with hookworm eggs).

The following courses of treatment are recommended:

Antiparasitic agents

Thiabendazole
- Topical application – early and localized lesions
- Oral administration – this is recommended in case of extensive lesions or if the topical treatment does not provide the desired results
Albendazole
- Benzimidazole drug commonly recommended as treatment for infestations with parasitic worms
- Better tolerated than Thiabendazole
Mebendazole
- Generally recommended for parasitic infestations, including the one with hookworms
- Oral administration
- Low toxicity drugs, easily absorbed into the bloodstream
Ivermectin
- Broad-spectrum anti-parasitic drug
- Commonly recommended for parasitic infestations, including hookworms and other intestinal worms
- Kills the larvae but not the adult worms
- Potential side-effects include neurotoxicity (the central nervous system is depressed and ataxia can occur, among other serious symptoms)
- Oral or injectable administration
- Contraindicated in children and in women who are breastfeedings

Antibiotic therapy

Recommended in case of secondary infections caused by excessive scratching

Cryotherapy

Liquid nitrogen is used on the larval burrow
Other choices for freezing include: Ethylene chloride spray and Solid carbon dioxide
This procedure presents increased risk of blistering or ulceration

Anti-itchiness cream

Relieves the intense pruritus
Topical corticosteroids – hydrocortisone cream
Calamine lotion – this has a soothing effect for the skin, relieving the itchiness and also reducing the inflammation