From the Guidelines
The true statement regarding Entamoeba histolytica is that Diloxanide Furoate is an effective luminal agent. This is based on the fact that luminal agents such as Diloxanide Furoate are used to treat the cyst form of the parasite in the intestinal lumen, preventing further transmission and recurrence of the disease 1. Some key points to consider when dealing with Entamoeba histolytica include:
- The parasite is transmitted through the fecal-oral route, primarily via ingestion of contaminated food or water containing cysts of the parasite.
- E. histolytica can cause invasive amebiasis, potentially spreading to extraintestinal sites like the liver, lungs, and brain, with liver abscesses being the most common complication.
- Diagnosis typically involves microscopic examination of stool samples or serological tests.
- Treatment usually consists of metronidazole followed by a luminal agent like paromomycin to eliminate cyst passage.
- It is essential to note that while Entamoeba histolytica can cause severe disease, not all strains are pathogenic, and asymptomatic carriers can exist 1. In terms of the options provided:
- A: Diloxanide Furoate is an effective luminal agent, which is true.
- B: It is not a common cause of traveler’s diarrhea, as other pathogens like bacteria and viruses are more frequently associated with this condition.
- C: While E. histolytica can cause liver abscesses, the term "pyogenic liver abscess" typically refers to abscesses caused by bacterial infections.
- D: Liver abscesses caused by E. histolytica are more commonly found in the right lobe of the liver, not the left.
- E: Metronidazole is effective in treating invasive disease caused by E. histolytica.
From the FDA Drug Label
Metronidazole possesses direct trichomonacidal and amebacidal activity against T. vaginalis and E. histolytica. Metronidazole tablets are indicated in the treatment of acute intestinal amebiasis (amebic dysentery) and amebic liver abscess. The correct answer is: A. Diloxanide Furoate is an effective luminal agent is not supported by the text, however,
- B. It is a common cause of traveler’s diarrhea is not directly supported.
- C. It may cause pyogenic liver abscess is supported in the sense that it causes liver abscess, but the text does not specify "pyogenic".
- D. It usually cause abscess in the left lobe of the liver is not supported by the text.
- E. Metronidazole is ineffective in treating invasive disease is not supported, metronidazole is effective in treating invasive disease, specifically amebic liver abscess. The most accurate answer based on the provided text is A is incorrect based on the text provided, but C is the closest to being correct, in that Entamoeba histolytica may cause liver abscess, however the term "pyogenic" is not used in the text. The text does support that Metronidazole is effective in treating amebiasis, including liver abscess, which is caused by Entamoeba histolytica 2, 2.
From the Research
Entamoeba histolytica Statements
- The following statements are given regarding Entamoeba histolytica:
- A. Diloxanide Furoate is an effective luminal agent
- B. It is a common cause of traveler’s diarrhea
- C. It may cause pyogenic liver abscess
- D. It usually cause abscess in the left lobe of the liver
- E. Metronidazole is ineffective in treating invasive disease
Analysis of Statements
- Statement A: Diloxanide Furoate is an effective luminal agent. This statement is supported by studies 3, 4, 5, 6, which show that diloxanide furoate is used for treating asymptomatic or mildly symptomatic persons who are passing cysts of Entamoeba histolytica and is effective in treating luminal infections.
- Statement B: It is a common cause of traveler’s diarrhea. There is no evidence in the provided studies to support this statement.
- Statement C: It may cause pyogenic liver abscess. While Entamoeba histolytica can cause liver abscess, the provided studies 4, 5 do not specify that it is pyogenic.
- Statement D: It usually cause abscess in the left lobe of the liver. The provided studies do not specify the location of the liver abscess.
- Statement E: Metronidazole is ineffective in treating invasive disease. This statement is not supported by the studies 4, 5, 6, which show that metronidazole is effective in treating invasive amebiasis, including amebic liver abscess.