ascaridiasis

What is Ascaridiasis?

Ascaridiasis, also known as ascariasis, is a parasitic infection caused by the roundworm Ascaris lumbricoides. This intestinal nematode (roundworm) infects an estimated 772-892 million people globally, making it one of the most common helminthic infections worldwide.

Key Facts:

• The larvae and adult forms of the parasite live in a person's intestines.
• People get ascariasis by consuming contaminated soil, food, or water that contains mature eggs from the roundworm.
• The infection can cause symptoms such as shortness of breath, fever, abdominal swelling, and abdominal pain, especially if the number of worms is large.

Life Cycle:

The life cycle of Ascaris lumbricoides involves ingestion of contaminated soil or food, followed by hatching of eggs in the duodenum. The resulting larvae penetrate the small bowel wall, migrate through the liver and lungs, and eventually mature into adult worms that live in the intestines.

Risk Factors:

The risk factors for ascariasis include age, with children under 10 years old being most affected. Other factors may contribute to the spread of the infection, such as poor sanitation, lack of access to clean water, and inadequate hygiene practices.

Prevalence:

Ascariasis is a significant public health problem in tropical and subtropical countries around the world, particularly in Sub-Saharan Africa, Latin America, China, and East Asia. It is estimated that approximately one billion people worldwide are infected with Ascaris lumbricoides, resulting in over 60,000 deaths annually.

References:

• [1] The roundworm Ascaris lumbricoides is the primary species involved in human infections globally.
• [2-5] Ascariasis can cause symptoms such as shortness of breath and fever in the beginning of the disease, followed by abdominal swelling and pain.
• [6-8] The life cycle of Ascaris lumbricoides involves ingestion of contaminated soil or food, hatching of eggs in the duodenum, penetration of the small bowel wall, migration through the liver and lungs, and eventual maturation into adult worms that live in the intestines.
• [9-11] The risk factors for ascariasis include age, poor sanitation, lack of access to clean water, and inadequate hygiene practices.

Diagnostic Tests for Ascaridiasis

Ascaridiasis, also known as ascariasis, is a parasitic infection caused by the roundworm Ascaris lumbricoides. Diagnosing this condition can be challenging due to its similar symptoms with other illnesses. However, various diagnostic tests are available to confirm the presence of the infection.

Stool Tests

• Stool tests are the most common and effective method for diagnosing ascariasis. They involve examining a stool sample under a microscope for eggs or larvae of the roundworm.
• The Kato-Katz test is a type of stool test that uses a special technique to concentrate the eggs and make them easier to detect.
• Stool tests can be performed in a laboratory setting, and results are usually available within a few hours.

Imaging Tests

• Imaging tests such as X-rays, computed tomography (CT) scans, and magnetic resonance imaging (MRI) may also be used to diagnose ascariasis.
• These tests can help visualize the presence of adult worms in the intestines or other parts of the body.
• However, imaging tests are not always necessary and may only be recommended in severe cases.

Other Diagnostic Tests

• Blood tests, including complete blood count (CBC) and eosinophil count, may also be performed to diagnose ascariasis.
• These tests can help detect any changes in the body's response to the infection.
• However, these tests are not as specific for ascariasis as stool tests.

References

• [1] Stool tests are the most common and effective method for diagnosing ascariasis. (Source: #9)
• The Kato-Katz test is a type of stool test that uses a special technique to concentrate the eggs and make them easier

Treatment Options for Ascaridiasis

Ascaridiasis, also known as ascariasis, can be effectively treated with medications that target the roundworms causing the infection.

• Albendazole: This is the drug of choice for treating ascariasis in stable patients older than 12 months with uncomplicated infection [6]. A single dose of albendazole 400 mg orally has been shown to be effective in eliminating the parasite [7].
• Other medications: In some cases, other medications such as mebendazole may also be used to treat ascariasis. However, albendazole is generally considered the first-line treatment due to its high efficacy and safety profile.
• Treatment of complications: If the infection leads to complications such as bowel obstruction, treatment may involve intravenous hydration, nasogastric suctioning, electrolyte monitoring, and laparotomy if conservative management fails [8].

Key Points

• Albendazole is the drug of choice for treating ascariasis in stable patients older than 12 months.
• A single dose of albendazole 400 mg orally has been shown to be effective in eliminating the parasite.
• Other medications such as mebendazole may also be used to treat ascariasis, but albendazole is generally considered the first-line treatment.

References

[6] Oct 1, 2021 - Albendazole 400 mg one dose orally is the drug of choice for ascariasis in stable patients older than 12 months with uncomplicated infection. [7] Oct 3, 2024 - Treatment includes medicines such as albendazole that paralyze or kill intestinal parasitic worms. [8] Jan 10, 2023 - Treatment of bowel obstruction includes intravenous hydration, nasogastric suctioning, electrolyte monitoring, and laparotomy if conservative management fails.

Differential Diagnosis of Ascaridiasis

Ascaridiasis, also known as ascariasis, is a parasitic infection caused by the roundworm Ascaris lumbricoides. The differential diagnosis of ascaridiasis involves considering various conditions that may present with similar symptoms. Here are some of the key differential diagnoses:

• Peptic ulcer disease: Ascaridiasis can mimic peptic ulcer disease, especially in cases where there is abdominal pain and gastrointestinal bleeding.
• Intestinal obstruction: Intussusception caused by Ascaris lumbricoides can lead to intestinal obstruction, which may be mistaken for other causes of bowel obstruction.
• Asthma: The pulmonary phase of ascaridiasis can present with respiratory symptoms such as coughing and wheezing, making it difficult to distinguish from asthma.
• Acute appendicitis: The acute abdomen caused by ascaridiasis can be mistaken for acute appendicitis due to the similarity in presenting signs and symptoms.
• Biliary ascariasis: In cases where Ascaris lumbricoides infects the bile duct, it may cause biliary obstruction, which can mimic other conditions such as cholecystitis or ascending cholangitis.

Key Diagnostic Features

To diagnose ascaridiasis, clinicians must consider the following key features:

• Eosinophilia: The presence of eosinophilia in the blood is a characteristic feature of ascaridiasis.
• Radiographic findings: Migratory bilateral round infiltrates on chest X-ray are typical of the pulmonary phase of ascaridiasis.
• Stool examination: Finding characteristic eggs in stool or observing adult worms in stool or emerging from the nose or mouth can confirm the diagnosis.

Prevalence and Epidemiology

Ascaridiasis is a significant public health problem, particularly in developing countries. It affects an estimated 772-892 million people worldwide, with the highest prevalence in tropical and subtropical regions of Asia, Africa, and Latin America.

References:

• [5] Ascaris lumbricoides, sometimes just called Ascaris or ascariasis, is a parasitic worm that infects an estimated 772–892 million people globally.
• [10] Approximately one billion people worldwide are infected with Ascaris lumbricoides, and more than 60,000 people die from the disease annually.
• [11] Table 1 Differential diagnoses to ascariasis morbidity in humans, grouped by larval and intestinal stages of infection.