









































Pa
ge

 
1



Pa
ge

 
17

1

American Journal of  Medical 
Science and Innovation (AJMSI) 

Recurrent Symptomatic Amoebiasis in a Rural Kenyan Hospital: A Case Report
Vonwicks C. Onyango1*, Samuel M. Gachie1, Boniface Mutiso1, Dominic Mutua1, Nicholas M. Mutuma1

Volume 2 Issue 2, Year 2023
ISSN: 2836-8509 (Online)

DOI: https://doi.org/10.54536/ajmsi.v2i2.2173
https://journals.e-palli.com/home/index.php/ajmsi

Article Information ABSTRACT

Received: September 25, 2023
Accepted: October 23, 2023
Published: October 30, 2023

Entamoeba histolytica is an extraintestinal protozoa that is feco-orally transmitted and 
exists as cysts or trophozoites, which may cause either asymptomatic infection or invasive 
intestinal and extraintestinal disease, respectively. Most infections (amoebiasis) are found in 
communities with poor environmental sanitation and unhygienic water and food handling 
practices. Recurrent symptomatic intestinal amoebiasis is associated with significant personal 
and public health cost implications and warrants a deliberate and thorough search for a 
source of  the feco-oral transmission. In this study, we present a case of  a woman with 
recurrent symptomatic amoebiasis to underscore the importance of  a detailed social history 
in establishing source control in the case management of  amoebiasis.

Keywords
Amoebiasis, Entamoeba 
Histolytica, Feco-Oral 
Transmission, Metronidazole, 
Invasive Amoebiasis, Recurrent 
Amoebiasis, Kenya

1 St. Joseph Rift Valley Hospital, Gilgil, Nakuru County, Kenya
* Corresponding author’s e-mail: drvonczelo@gmail.com

INTRODUCTION
Amoebiasis is a parasitic disease caused by the extracellular 
intestinal protozoa Entamoeba histolytica (i.e., E. histolytica), 
which is the most common cause of  symptomatic 
disease. Three other species of  intestinal amoebae are 
morphologically identical to E. histolytica and include E. 
dispar, E. bangladeshi, and E. moshkovskii. The pathogenicity 
of  the non-histolytica species is unclear, with E. dispar 
generally considered non-pathogenic. Amoebiasis occurs 
worldwide, with a disproportionately higher prevalence 
in developing and low-income countries due to low 
socioeconomic status and poor sanitation conditions, 
e.g., in India, Africa, and parts of  central and south 
America (Carrero et al., 2020). A systematic scoping study 
showed wide variations in the prevalence of  amoebiasis 

in Eastern Africa, i.e., 4.6-15.3% (Ethiopia), 5.9-58.3% 
(Kenya), 54.5% (Rwanda), 0.7-2.7% (Sudan), and 19.93% 
(Uganda) (Ngowi, 2020). The parasite exists in a cyst 
form (the infective stage) and a trophozoite form (which 
causes invasive intestinal disease). Infection occurs 
when amoebic cysts are ingested in contaminated food 
or water via the feco-oral transmission route. Sexual 
transmission may also be seen in men having sex with 
other men. The cysts pass through the stomach to the 
small intestines, where they excyst in the terminal ileum 
to form invasive trophozoites. The latter can invade the 
mucosae of  the colon to cause invasive bloody diarrhea 
(amoebic dysentery) (Marie & Petri, 2013) or cause 
extra-intestinal disease, e.g., amoebic abscess in the liver 
(Usuda et al., 2022), and in the brain and lungs (Petri & 

Figure 1: Life cycle of  E. histolytica/E. dispar. (Ximénez et al., 2011)



Pa
ge

 
17

2

https://journals.e-palli.com/home/index.php/ajmsi

Am. J. Med. Sci. Innov. 2(2) 171-174, 2023

Haque, 2013; Shamsuzzaman & Hashiguchi, 2002). A 
diagnosis can be made by various methods, including 
stool microscopy, which demonstrates amoebic cysts and 
trophozoites; rapid antigen detection in stool or serum; 
molecular detection using polymerase chain reaction 
(PCR); antigen and antibody detection by serology; and 
histology from colonic samples (Saidin et al., 2019). 
Figure 1, adapted from the excellent review by Ximenez 
and colleagues, illustrates the life cycle of  E. histolytica 
and E. dispar, with the corresponding appearances of  
the cysts and trophozoites under microscopy (Ximénez 
et al., 2011). Antimicrobials commonly used to treat 
amoebiasis include nitroimidazoles (metronidazole, 
tinidazole, secnidazole, etc.), paromomycin, iodoquinol, 
and diloxanide furoate (Morán et al., 2023). Drug therapy 
must be combined with improved hygienic handling of  
food and drinks, as well as environmental sanitation, to 
prevent feco-oral transmission. 

Case Summary
Clinical Presentation and Management
A 53-year-old single mother of  five from Gilgil, Nakuru 
County, Kenya, with a history of  well-controlled 
hypertension, was first treated for symptomatic 
amoebiasis in our facility in February 2020. She had 
presented with a two-week history of  cramping 
periumbilical and suprapubic pains, flatulence, nausea 
with a one-day history of  postprandial non-bilious 
vomiting, and loose mucoid non-bloody stools (about 
3-4 episodes daily) with associated tenesmus. She was 
moderately dehydrated at the time but hemodynamically 
stable. She was afebrile, with abdominal examination 
findings only significant for vague diffuse periumbilical 
and suprapubic area tenderness without any features of  
peritonism. The rest of  the physical examination was 
unremarkable. Her stool microscopy showed numerous 
trophozoites of  Entamoeba histolytica with many pus 
cells (qualitative report). She was treated with 5 days of  
oral metronidazole 400mg thrice daily (as per our local 
protocol), antiemetics, rehydration, and education on 
personal hygiene, environmental sanitation, and food and 
water sanitation practices. One month later, her stool was 
normal, and she was asymptomatic. However, from the 
months of  July to November 2020, she re-presented with 
similar gastrointestinal symptoms and tested positive for 
Entamoeba histolytica trophozoites in her stool following a 
wet-preparation microscopy. She remained asymptomatic 
throughout 2021 during routine follow-ups for the 
hypertension, with normal random stool examinations. 
However, in 2022, she developed similar recurrent 
gastrointestinal symptomatology with positive stool 
microscopy for Entamoeba histolytica trophozoites from 
the months of  September to December 2022. She was 
treated each time with various nitroimidazole compounds, 
i.e., metronidazole at a dose of  400mg thrice daily for 5 
days or tinidazole at 1gm twice daily for 3 days, together 
with antiemetics (metoclopramide 10mg thrice daily for 
the duration of  the metronidazole of  tinidazole) and 

other supportive therapy. She did not have any episodes 
of  vomiting while on the antiprotozoal, and she was fully 
compliant with her medications.

Further Social History
She lives alone in a 2-bedroom house in a 2-story 
apartment complex, which she shares with at least 
14 other different families. She uses a pit latrine and a 
simple bathing room, which she shares with one other 
household. These are located about 10 meters behind the 
apartment complex, with the design and allocation such 
that two families share a pit latrine and a bathroom and 
are also responsible for cleaning them. She obtains water 
for drinking and other home uses from a large borehole 
in front of  the apartment complex and several plastic 
water tanks that harvest rainwater from the apartment 
roof. She reported regularly washing her hands with water 
and soap (and more so with the advent of  the COVID-19 
pandemic) and regularly boiling her drinking water, which 
she stored in two plastic 20-liter jerrycans. No other 
person from her apartment complex had been treated for 
recurrent diarrheal illness in that period. Importantly, 2 
of  her daughters who had visited her overnight at various 
times in 2020 and 2022 had each subsequently been treated 
for stool-microscopy-confirmed amoebiasis (positive 
trophozoites) about 5-7 days after each visit. In 2021, 
she had temporarily relocated to stay with her ailing sister 
about 10 kilometers away, where she used running tap 
water from the local municipal supply lines. In view of  the 
foregoing, the source of  the recurrent amoeba infection 
was deemed to be within her house, especially from the 
stored water in the jerrycans. A community health worker 
with basic training in public health and sanitation was 
consulted to visit her at home and inspect her water and 
food handling practices with a view to locating the source 
of  the recurrent amoebic infection. Upon closer inquiry, it 
was revealed that she had refilled the jerrycans on several 
occasions with “clean” water from a specific local water 
vendor during periods of  water scarcity in the area and 
had neither boiled nor purified the said water, which was 
reportedly marketed as “fresh spring water”, and whose 
actual source was unknown. When she discarded all the 
stored jerrycan water and thoroughly washed the cans 
with hot water and soap, the amoebiasis stopped. The 
matter was reported to the local public health authorities 
for administrative remedial interventions. She has had 
no more presentations with amoebiasis, and her random 
stool microscopic examinations from time to time have 
been normal.

DISCUSSION
E. histolytica is transmitted by the feco-oral route when 
amoebic cysts contaminating food and drinks are 
ingested. These cysts contaminate food, water, and drinks 
during the processes of  preparation, handling, packaging, 
storage in various containers and bottles, transportation, 
serving, and consumption. Once ingested, the cysts 
reach the terminal ileum, where excystation occurs with 



Pa
ge

 
17

3

https://journals.e-palli.com/home/index.php/ajmsi

Am. J. Med. Sci. Innov. 2(2) 171-174, 2023

the release of  active trophozoites, which may invade the 
colonic mucosa to cause active disease or remain dormant 
in the mucosa, causing chronic asymptomatic infection. A 
history of  feco-oral transmission must always be sought 
meticulously through detailed inquiry about personal 
hygiene, environmental sanitation, sources of  food and 
water, and water storage and handling at home and in 
the community. In most cases, infections (including 
recurrent infections) occur due to a lack of  access to 
safe drinking water and sanitation facilities (Atabati et al., 
2020). Our patient’s source of  recurrent infection was 
the contaminated water sold to her by a vendor during 
periods of  water scarcity in her home. She did not boil the 
water or treat it in any way before storing it in the various 
jerrycans. On further probing, it was revealed that the same 
vendor had also sold water to three other families in the 
apartment complex, but each of  these families had boiled 
all the water and cooled it before use. None of  them got 
any amebic infections. Although a majority of  patients 
who get infected remain asymptomatic, some present 
with symptomatic disease of  varying severity (e.g., from 
mild to severe gastroenteritis to severe life-threatening 
fulminant amebic colitis with toxic megacolon, colonic 
perforation and peritonitis, etc.), including extra-intestinal 
manifestations, e.g., amebic liver and lung abscess (Carrero 
et al., 2020; Kantor et al., 2018; Usuda et al., 2022). Anti-
amoebic drugs are recommended to cure amebiasis 
and may act only in the intestinal lumen (i.e., luminal 
amebicides, e.g., paromomycin, iodoquinol, diloxanide 
furoate, nitazoxanide, and metronidazole) or in the tissues 
(i.e., tissue amebicides, e.g., metronidazole, tinidazole, and 
emetine) (Morán et al., 2023). Metronidazole remains the 
first-line drug in the treatment of  amebiasis, as it is active 
as both a tissue and a luminal amebicide. Our patient 
was successfully treated with metronidazole or tinidazole 
during various presentations as per the local guidelines. 
The amebic cysts and trophozoites can be eliminated by 
improved water safety (e.g., through boiling and filtration 
or adding chlorine to water) and sanitation. It is quite 
interesting that our patient never had amoebic cysts in 
her stool during asymptomatic random stool microscopy 
examinations. The simple act of  washing hands with soap 
and water can reduce mortality associated with diarrheal 
illnesses (of  which amoebiasis is a major etiology)  by up 
to 50% (Kantor et al., 2018). There are ongoing trials at 
various phases to develop vaccines effective against E. 
histolytica infections in humans (Quach et al., 2014; Singh 
et al., 2016).

CONCLUSION
A thorough history must be sought in all cases of  
suspected and confirmed amoebiasis to determine the 
source of  the feco-oral transmission. This is especially 
important in cases of  recurrent infections. Metronidazole 
remains the first-line amebicide for effective drug 
treatment of  amoebiasis. Most importantly, drug therapy 
must be done in conjunction with improved personal 
hygiene through frequent hand-washing with soap and 

water, as well as improved environmental sanitation and 
water safety.

REFERENCES
Atabati, H., Kassiri, H., Shamloo, E., Akbari, M., 

Atamaleki, A., Sahlabadi, F., Linh, N. T. T., Rostami, 
A., Fakhri, Y., & Khaneghah, A. M. (2020). The 
association between the lack of  safe drinking water 
and sanitation facilities with intestinal Entamoeba 
spp infection risk: A systematic review and meta-
analysis. PLoS One, 15(11), e0237102. https://doi.
org/10.1371/journal.pone.0237102 

Carrero, J. C., Reyes-López, M., Serrano-Luna, J., 
Shibayama, M., Unzueta, J., León-Sicairos, N., & 
de la Garza, M. (2020). Intestinal amoebiasis: 160 
years of  its first detection and still remains as a 
health problem in developing countries. Int J Med 
Microbiol, 310(1), 151358. https://doi.org/10.1016/j.
ijmm.2019.151358 

Kantor, M., Abrantes, A., Estevez, A., Schiller, A., 
Torrent, J., Gascon, J., Hernandez, R., & Ochner, 
C. (2018). Entamoeba Histolytica: Updates in 
Clinical Manifestation, Pathogenesis, and Vaccine 
Development. Can J Gastroenterol Hepatol, 2018, 
4601420. https://doi.org/10.1155/2018/4601420 

Marie, C., & Petri, W. A., Jr. (2013). Amoebic dysentery. 
BMJ Clin Evid, 2013. 

Morán, P., Serrano-Vázquez, A., Rojas-Velázquez, L., 
González, E., Pérez-Juárez, H., Hernández, E. G., 
Padilla, M. L. A., Zaragoza, M. E., Portillo-Bobadilla, 
T., Ramiro, M., & Ximénez, C. (2023). Amoebiasis: 
Advances in Diagnosis, Treatment, Immunology 
Features and the Interaction with the Intestinal 
Ecosystem. Int J Mol Sci, 24(14). https://doi.
org/10.3390/ijms241411755 

Ngowi, H. A. (2020). Prevalence and pattern of  waterborne 
parasitic infections in eastern Africa: A systematic 
scoping review. Food Waterborne Parasitol, 20, e00089. 
https://doi.org/10.1016/j.fawpar.2020.e00089 

Petri, W. A., & Haque, R. (2013). Entamoeba histolytica brain 
abscess. Handb Clin Neurol, 114, 147-152. https://doi.
org/10.1016/b978-0-444-53490-3.00009-1 

Quach, J., St-Pierre, J., & Chadee, K. (2014). The future 
for vaccine development against Entamoeba histolytica. 
Hum Vaccin Immunother, 10(6), 1514-1521. https://
doi.org/10.4161/hv.27796 

Saidin, S., Othman, N., & Noordin, R. (2019). Update on 
laboratory diagnosis of  amoebiasis. Eur J Clin Microbiol 
Infect Dis, 38(1), 15-38. https://doi.org/10.1007/
s10096-018-3379-3 

Shamsuzzaman, S. M., & Hashiguchi, Y. (2002). Thoracic 
amebiasis. Clin Chest Med, 23(2), 479-492. https://doi.
org/10.1016/s0272-5231(01)00008-9 

Singh, R. S., Walia, A. K., Kanwar, J. R., & Kennedy, J. F. 
(2016). Amoebiasis vaccine development: A snapshot 
on E. histolytica with emphasis on perspectives of  
Gal/GalNAc lectin. Int J Biol Macromol, 91, 258-268. 
https://doi.org/10.1016/j.ijbiomac.2016.05.043 



Pa
ge

 
17

4

https://journals.e-palli.com/home/index.php/ajmsi

Am. J. Med. Sci. Innov. 2(2) 171-174, 2023

Usuda, D., Tsuge, S., Sakurai, R., Kawai, K., Matsubara, 
S., Tanaka, R., Suzuki, M., Takano, H., Shimozawa, 
S., Hotchi, Y., Tokunaga, S., Osugi, I., Katou, R., Ito, 
S., Mishima, K., Kondo, A., Mizuno, K., Takami, 
H., Komatsu, T., . . . Sugita, M. (2022). Amebic liver 
abscess by Entamoeba histolytica. World J Clin Cases, 
10(36), 13157-13166. https://doi.org/10.12998/

wjcc.v10.i36.13157 
Ximénez, C., Morán, P., Rojas, L., Valadez, A., Gómez, A., 

Ramiro, M., Cerritos, R., González, E., Hernández, 
E., & Oswaldo, P. (2011). Novelties on amoebiasis: a 
neglected tropical disease. J Glob Infect Dis, 3(2), 166-
174. https://doi.org/10.4103/0974-777x.81695


