From the Guidelines
Diloxanide Furoate is an effective luminal agent for treating Entamoeba histolytica infections. Entamoeba histolytica is a protozoan parasite that causes amebic dysentery and invasive amebiasis in humans. The parasite exists in two forms: the infectious cyst form which survives outside the host, and the trophozoite form which causes disease within the human intestine. When ingested, the cysts survive stomach acid and excyst in the intestine, where trophozoites can invade the intestinal mucosa causing ulceration and bloody diarrhea. In some cases, the parasite can spread hematogenously to extraintestinal sites, most commonly the liver, causing amebic liver abscesses. Diagnosis typically involves microscopic identification of cysts or trophozoites in stool samples or serological tests, as recommended by the 2017 Infectious Diseases Society of America clinical practice guidelines for the diagnosis and management of infectious diarrhea 1. Treatment for symptomatic infections usually consists of metronidazole followed by a luminal agent such as paromomycin or diloxanide furoate to eliminate intestinal cysts and prevent relapse. Key points to consider in the management of Entamoeba histolytica infections include:
- The use of metronidazole as the primary treatment for invasive amebiasis
- The importance of luminal agents, such as diloxanide furoate, in eliminating intestinal cysts and preventing relapse
- The need for proper diagnosis, including microscopic identification of cysts or trophozoites in stool samples or serological tests, as outlined in the guidelines 1.
From the FDA Drug Label
Metronidazole possesses direct trichomonacidal and amebacidal activity against T. vaginalis and E. histolytica. The correct answer is A. Diloxanide Furoate is an effective luminal agent is not supported by the text, however, The statement that Metronidazole is effective in treating invasive disease can be inferred from the text, which means option E. Metronidazole is ineffective in treating invasive disease is false. Also, Bactericidal concentrations of metronidazole have also been detected in pus from hepatic abscesses which means option C. It may cause pyogenic liver abscess is plausible, however, the text does not explicitly state that Entamoeba histolytica causes pyogenic liver abscess. The text does not provide information about the location of the liver abscess, so option D. It usually cause abscess in the left lobe of the liver cannot be confirmed. The text does not provide information about Entamoeba histolytica being a common cause of traveler’s diarrhea, so option B. It is a common cause of traveler’s diarrhea cannot be confirmed. Given the provided text, the only statement that can be confirmed as true is that Metronidazole is effective against Entamoeba histolytica, which implies that option E. Metronidazole is ineffective in treating invasive disease is false, however, this is not among the answer options. Among the provided options, only option A. Diloxanide Furoate is an effective luminal agent is related to the treatment of Entamoeba histolytica, and it is the only option that can be considered as true, based on general knowledge, although it is not supported by the provided text. However, according to the provided instructions, the answer should be based on the text, and the text does not support any of the options. Therefore, the answer should be: The FDA drug label does not answer the question.
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 2, 3, 4, 5, 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 3, 4 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 3, 4, 5, which show that metronidazole is effective in treating invasive amebiasis, including amebic liver abscess.