Amoebiasis: Safe During Pregnancy?

Amoebiasis is a disease caused by the Entamoeba histolytica parasite. It can affect anyone, including pregnant women, and is more common in developing countries with poor sanitation. The infection can be asymptomatic or present with mild to severe symptoms, such as lethargy, weight loss, abdominal pain, and diarrhoea. Amoebiasis can lead to complications such as inflammation and perforation of the colon, resulting in peritonitis. Extra-intestinal amoebiasis may also occur, affecting the liver, lungs, brain, and genital organs. Diagnosis is often based on stool examination, but molecular tests like PCR are more accurate. Treatment involves anti-amoebic medications, and the prognosis is generally good if treated promptly.

Amoebiasis in pregnancy: a review and update of the literature

Amoebiasis is a disease caused by the Entamoeba histolytica parasite, which is most commonly contracted in developing countries with poor sanitary conditions. It can affect anyone, including pregnant women, and can be asymptomatic or present with mild to severe symptoms. The most common symptoms include lethargy, weight loss, abdominal pain, and diarrhoea. Amoebiasis can lead to serious complications such as inflammation and perforation of the colon, resulting in peritonitis. Extra-intestinal amoebiasis may also occur, affecting the liver, lungs, brain, and genital organs. Diagnosis is often based on stool samples, but molecular biology-based tests and serology tests are more accurate. Treatment involves anti-amoebic medications, supportive care, and, in cases of amoebic liver abscess, aspiration and drainage of the abscess. Amoebiasis in pregnancy is rare but can have severe consequences if not diagnosed and treated promptly.

Amoebiasis in pregnancy and the puerperium

Amoebiasis, or infection with the intestinal protozoan *Entamoeba histolytica*, is a parasitic disease that can have serious consequences for pregnant women and their babies. The disease is transmitted by the ingestion of cysts, usually from contaminated food or water. While some people may be asymptomatic carriers, others may experience symptoms ranging from mild diarrhoea to fulminant dysentery.

Pregnancy and Puerperium

During pregnancy, amoebiasis can cause acute exacerbations of the disease with prominent symptoms, including bloody, dysenteric stools, moderate abdominal pain, and tenderness. The resulting fluid loss and electrolyte imbalance can adversely affect the outcome of pregnancy. Amoebiasis has also been associated with premature labour and delivery, and in rare cases, abortion.

In the Kilimanjaro Region of Tanzania, amoebiasis was found to be the second most prevalent parasitic infection during pregnancy, after malaria. A study showed that pregnant women infected with amoebiasis had a 79% increased risk of preterm delivery compared to uninfected women.

Diagnosis and Treatment

Diagnosis of amoebiasis is made by identifying *E. histolytica* in stool samples or biopsy specimens. Treatment should be tailored to the severity of symptoms, and asymptomatic women should delay treatment until after the first trimester or until after delivery. Metronidazole is the recommended treatment for both intestinal and extraintestinal amoebiasis, but its use during pregnancy, especially in the first trimester, is controversial due to potential mutagenic and carcinogenic effects. Alternative drugs include paromomycin and diloxanide furoate, which are considered safer during pregnancy.

Prevention

The prevention of amoebiasis during pregnancy involves minimising the risk of ingesting the *E. histolytica* cysts. This can be achieved by improving sanitation and personal hygiene, such as regular handwashing, and ensuring access to clean water and food.

Complications of amoebiasis in pregnancy and puerperium

Amoebiasis is a parasitic disease caused by the Entamoeba histolytica parasite, which affects around 10% of the global population. The parasite primarily infects the ileum and colon, and can lead to gastrointestinal issues such as colicky lower abdominal pain, mucus and blood in the stool, and acute exacerbations of the disease. While the infection is usually asymptomatic, it can cause severe complications in pregnant women, including bloody, dysenteric stools, fluid loss, and electrolyte imbalance, which can adversely affect the outcome of the pregnancy.

Amoebiasis during pregnancy can lead to several complications, including:

• Fulminant Amoebic Colitis: This is a severe complication that can occur during pregnancy and puerperium, and has been associated with fatal outcomes.
• Hepatic Abscess: While hepatic amebiasis is not commonly observed during pregnancy, it can occur and lead to serious complications. The abscess usually develops in the posterior portion of the right lobe of the liver and can rupture, leading to a morbid condition.
• Intestinal Complications: Amoebiasis can cause intestinal issues such as ulceration, extensive destruction of the colonic mucosa, and bowel perforation.
• Pregnancy Outcomes: Amoebiasis during pregnancy has been associated with an increased risk of preterm delivery. Additionally, the immunocompromisation during pregnancy can lead to reduced production of IgA, resulting in sub-chronic inflammation and placenta dysfunction, which has been linked to preeclampsia, indicated preterm delivery, and fetal growth restriction.
• Maternal Anaemia: Pregnant women infected with malaria had a 33% increased odds of developing maternal anaemia compared to uninfected women.

Diagnosis and treatment of amoebiasis in pregnancy

Amoebiasis is a disease caused by the pathogenic species of amoebae, most commonly Entamoeba histolytica. It can affect anyone, including pregnant women, and tends to be more common in people living in or travelling to developing countries with poor sanitary conditions. Diagnosis of amoebiasis in pregnancy is challenging due to its non-specific symptoms and the need for a high index of suspicion. The diagnosis is typically based on microscopy examination of stool samples, but molecular biology-based tests, such as polymerase chain reaction (PCR) assays, can provide a quicker and more accurate diagnosis by differentiating Entamoeba histolytica from non-pathogenic species. Treatment of amoebiasis in pregnancy involves the use of anti-amoebic medications, such as metronidazole, and supportive care. Complications, such as amoebic liver abscesses, can be managed with radiology image-guided aspiration and drainage of the abscess. Laparotomy may be necessary in some cases.

Pathophysiology of amoebiasis

Amoebiasis is an infection of the human gastrointestinal tract by Entamoeba histolytica, a protozoan parasite that is capable of invading the intestinal mucosa and may spread to other organs, mainly the liver. The motile form of E. histolytica, the trophozoite, lives in the lumen of the large intestine, where it multiplies and differentiates into the cyst, the resistant form responsible for the transmission of the infection. Cysts are excreted in stools and may be ingested by a new host via contaminated food or water. The parasite excysts in the terminal ileum, with each emerging quadrinucleate trophozoite giving rise to eight uninucleated trophozoites. Trophozoites may invade the colonic mucosa and cause dysentery and, through spreading via the bloodstream, may give rise to extraintestinal lesions, mainly liver abscesses.

The powerful lytic activity of E. histolytica has inspired a variety of approaches aimed at understanding the pathogenesis of invasive amoebiasis. Most studies have focused on a single factor in an attempt to dissect the multiple mechanisms used by the parasite that ultimately result in tissue destruction. The basic mechanisms involved in the production of focal lytic lesions include complex multifactorial processes in which lectins facilitate adhesion, proteases degrade extracellular matrix components, porins help nourish the parasite and may also kill incoming polymorphonuclear leukocytes and macrophages, and motility is used by the parasite to invade deeper layers of the colon.

Frequently asked questions