Cutaneous Larva Migrans - Causes, Symptoms, and Prevention

Introduction:

Cutaneous larva migrans is a skin infection caused by animal hookworm. It is caused by the parasite known as Ancylostomatidae. The parasite lives in the intestine of dogs, cats, and wild animals. Cutaneous larva migrans means moving larvae in the skin. It is also known as creeping eruption, which means lesions migrate or move due to the moving parasite in the skin. Cutaneous larva migrans are called by different names in different countries. It is known as ground itch or sandworms as larvae reside in the sandy soil in the southern United States. The term Cutaneous larva migrans was described by Crocker in 1893. The disease occurs worldwide but is more common in warmer climates and tropical and subtropical areas, including the southeast United States, Latin America, Southeast Asia, and Africa. The larvae penetrate the skin when an individual walks barefoot on contaminated soil. Humans are infected through contact with contaminated soil.

What Are the Causes of Cutaneous Larva Migrans?

Cutaneous larva migrans are caused by multiple types of hookworms. The parasite lives in the intestine of dogs and cats. The common causes are:

1. Ancylostoma braziliense is a hookworm of dogs and cats found in the United States, South Africa, and the Caribbean.

2. Ancylostoma caninum is a hookworm of a dog found in Australia.

3. Bunostomum phlebotomum is a cattle hookworm.

Who Are at Risk of Cutaneous Larva Migrans?

Cutaneous larva migrans affects all age groups, sex, and race. When exposed to hookworm larvae, a person acquires a disease. The disease is most commonly found in tropical and subtropical areas. The person at risk includes:

• People whose occupation or hobby is in contact with warm, moist, and sandy soil are at more risk.

• The person who walks barefoot on the beach.

• Sunbathers.

• The children who play in the sandpit.

• Farmers, gardeners, hunters, electricians, and carpenters.

• Pest exterminators (a person whose job is to kill insects and animals).

• The people who work in the forest areas.

How Do Cutaneous Larva Migrans Spread?

The disease life cycle starts with the presence of adult hookworm in the intestine of dogs and cats. The life cycle is described as follows:

• The adult hookworm lays eggs in the intestine. Eggs are passed into the feces of the dogs and cats and then into the soil.

• Under warm and moist conditions, the larvae incubate and mature within one to two days. The mature larvae are the rhabditiform larvae that grow for five to ten days.

• The eggs passed through several molts (to shed hair or feathers to form a new growth) to form infective filiform or third-stage larvae. They are capable of surviving outside the body for four weeks.

• Once the filiform larva comes in contact with the skin of an animal, the larva penetrates the skin and enters the blood and lymph vessels. It can enter through intact skin, hair follicles, or tiny cracks. Then the larvae are transported to the pulmonary vessels through the heart and bone through the lung alveoli.

• They enter the airways to reach the pharynx, where they are swallowed, enter the stomach, and then into the small intestine. In the small intestine, the larvae mature into adult worms. The adult worms attach to the gut wall and lay more eggs to repeat the life cycle.

In humans, the larvae can penetrate through the hair follicles, cracks, or intact skin. The larvae can rarely penetrate the basement membrane (the layer between the upper layer and the underlying skin). In animals, the larvae can penetrate the deeper layer of the skin.

What Are the Signs and Symptoms of Cutaneous Larva Migrans?

The clinical features of the disease are as follows:

• The eruption occurs at the penetration site of hookworm larvae. The eruption can be red, itchy, and look like a wheel lesion.

• There may be a tingling or pricking sensation within 30 minutes of larva penetration. Then the larva remains latent for weeks or months.

• After some weeks, it shows migration activity that creates two to three-millimeters-wide snake-like tracts (erythematous tunnels) stretching three to four centimeters from the penetration site.

• The eruptions are slightly raised, pink-colored, and cause itching.

• There may be perianal involvement due to reinfection from the stool.

• Urticaria (a raised, itchy rash on the skin).

• Swelling can also be present.

• The sites most commonly affected are the feet, hands, and spaces between the toes, knees, and buttocks.

How Can Cutaneous Larva Migrans Be diagnosed?

The diagnosis can be made in the following ways:

1. Doctor Evaluation - The doctor evaluates the diagnosis based on the location of the rashes and the patient's history of contact with the soil.

2. Microscopy - To find the hookworm eggs or larvae in the feces.

3. Skin Biopsy - The test reveals the larva within the circular canal.

There is no blood test for zoonotic hookworm infection.

How Can Cutaneous Larva Migrans be Managed?

• Cutaneous larva migrans normally disappear within six months. If the infection continues even after six months, the possible complication proposes that treatment be given to prevent the disease.

• Anthelmintic drugs such as Tiabendazole, Albendazole, Mebendazole, and Ivermectin are effective drugs prescribed to prevent the disease. The doctor should give oral Albendazole 400 mg daily for three to five days.

• Topical Thiabendazole (10 % solution or 15 % ointment) is prescribed for localized lesions. If topical treatment gets failed, then oral treatment is prescribed.

• Itching decreases after 24 to 48 hours of taking antihelmintic drugs, and the lesion will cure within one week.

• Physical treatment such as liquid nitrogen cryotherapy (application of extreme cold or freeze to destroy the abnormal tissue) or carbon dioxide laser is used to destroy the larvae.

• Antihistamines and topical corticosteroids with antihelmintic drugs are prescribed to relieve an itch.

• If a person acquires a secondary infection, then antibiotics are prescribed.

How Can Cutaneous Larva Migrans be Prevented?

These are the steps that the person should adopt to prevent the disease.

• A person in the community should wear shoes while walking on sand because walking barefoot in contaminated areas will acquire the disease.

• People should wear proper clothes because the disease is a skin infection.

• Avoid sitting or lying down in contaminated areas.

• Avoid the areas invaded by animals, especially dogs, and cats.

• Avoid traveling to disease-prone areas.

Conclusion:

Cutaneous larva migrans are a skin disease found in tropical and subtropical areas. People should adopt preventive measures to prevent and eliminate the disease. The healthcare team, including doctors, nurses, and pharmacists, should work together to educate the people about the disease and the treatment's importance. The doctor should monitor the patient, direct the treatment, and educate the patient and their families. The healthcare team works together to achieve better outcomes.