Amoebic dysentery - Entamoeba Histolytica

Summary

The video explores amoebic dysentery caused by Entamoeba histolytica, a protozoan parasite that infects up to 10% of the global population. It explains the life cycle of the parasite, including its cyst and trophozoite forms, and how these lead to non-invasive or invasive infections. The non-invasive infection causes mild symptoms, while invasive infections can result in severe complications such as ulcers, liver abscesses, and even brain abscesses. The video covers treatment options with drugs like metronidazole and emphasizes the importance of diagnosing the infection through stool examination.

Takeaways

• 😀 Entamoeba histolytica is a protozoan parasite that can cause amoebic dysentery, affecting up to 10% of the global population.
• 😀 Amoebic dysentery is characterized by inflammatory diarrhea, ulcers, and painful gut issues.
• 😀 Entamoeba histolytica exists in two forms: the cyst form (infective) and the trophozoite form (mobile).
• 😀 The cyst form of Entamoeba histolytica enters the human body primarily through contaminated food or water.
• 😀 The cysts pass through the stomach and enter the small intestine, where they undergo excitation to form trophozoites.
• 😀 Trophozoites move to the large intestine, where they colonize and may cause a non-invasive infection, generally asymptomatic with mild diarrhea.
• 😀 Invasive infection occurs in about 10% of cases, where trophozoites invade the intestinal walls, leading to ulcers and immune response.
• 😀 Invasive infections can lead to severe complications like liver abscesses, lung abscesses, and, in rare cases, brain abscesses.
• 😀 Amoebic dysentery is marked by bloody and mucous-filled stools due to damage in the colon.
• 😀 Treatment for invasive Entamoeba histolytica infections includes the use of azoles, specifically metronidazole.
• 😀 Diagnosis of Entamoeba histolytica infections is often done by examining fecal samples for cysts.

Q & A

What is amoebic dysentery and what causes it?

Amoebic dysentery is an inflammatory diarrhea caused by the protozoan parasite Entamoeba histolytica, which can lead to ulcers and severe gastrointestinal discomfort.

How is Entamoeba histolytica transmitted?

Entamoeba histolytica is transmitted primarily through the ingestion of cysts in contaminated food or water, typically through fecal-oral transmission.

What are the two forms of Entamoeba histolytica?

Entamoeba histolytica exists in two forms: the cyst form (infective) and the trophozoite form (mobile and active).

What happens during the excitation process of Entamoeba histolytica?

Excitation is the process where cysts of Entamoeba histolytica transform into trophozoites in the small intestine, which then migrate to the colon to establish colonization.

What distinguishes an invasive infection from a non-invasive infection caused by Entamoeba histolytica?

In a non-invasive infection, the trophozoites remain in the colon and cause mild symptoms such as diarrhea, while in an invasive infection, trophozoites invade and destroy intestinal cells, causing more severe symptoms like ulcers and potentially spreading to other organs.

What are the symptoms of invasive Entamoeba histolytica infection?

Symptoms of invasive infection include severe inflammatory diarrhea, colitis, blood and mucus in stool, ulcers, and potentially liver, lung, or brain abscesses.

How does Entamoeba histolytica affect the gastrointestinal system during an invasive infection?

During an invasive infection, trophozoites invade the epithelial cells of the intestines, causing cell lysis, which leads to the formation of ulcers and inflammatory responses, further damaging the intestinal lining.

What is the role of neutrophils in the immune response to an invasive Entamoeba histolytica infection?

Neutrophils respond to the invasion by Entamoeba histolytica, contributing to further tissue damage through inflammation, which worsens the ulceration and overall infection.

How can invasive Entamoeba histolytica infections affect organs outside the intestines?

If trophozoites enter the bloodstream, they can spread to organs such as the liver, lungs, and rarely the brain, leading to abscess formation in these organs.

What is the primary treatment for Entamoeba histolytica infections?

The primary treatment for Entamoeba histolytica infections, especially invasive ones, is with medications such as metronidazole, which are part of the azole drug class.