Blastocystis hominisandEndolimax nanaCo-Infection Resulting in Chronic Diarrhea in an Immunocompetent Male

Abstract

Blastocystis hominis and Endolimax nana exist as two separate parasitic organisms; however co-infection with the two individual parasites has been well documented. Although often symptomatic in immunocompromised individuals, the pathogenicity of the organisms in immunocompetent subjects causing gastrointestinal symptoms has been debated, with studies revealing mixed results. Clinically, both B. hominis and E. nana infection may result in acute or chronic diarrhea, generalized abdominal pain, nausea, vomiting, flatulence and anorexia. We report the case of a 24-year-old immunocompetent male presenting with chronic diarrhea and abdominal pain secondary to B. hominis and E. nana treated with metronidazole, resulting in symptom resolution and eradication of the organisms. Our case illustrates that clinicians should be cognizant of both B. hominis and E. nana infection as a cause of chronic diarrhea in an immunocompetent host. Such awareness will aid in a timely diagnosis and possible parasitic eradication with resolution of gastrointestinal symptoms.

Parasitic Infestation in the Incidence of Diarrhea Among Toddlers in Jakarta, Bogor, Banjarmasin and Makassar

“…The incidence of Blastocystis hominis infection is 30-50% in developing and tropical countries and 1.5-10% in developed countries. In Indonesia the incidence of Blastocystis hominis infection is 60% [23]. Research conducted on pediatric diarrhea in Iraq from 2003 to 2004 obtained data that Giardia lamblia became the most parasitic with a prevalence of 45.54% followed by Entamoeba histolytica 23.44%, Oxyuris vermicularis 12.7%, Hymenolepis nana 9.82%, Trichuris trichiura 5.4%, and Ascaris lumbricoides 2.2% [24].…”

Systematic review on Endolimax nana: A less well studied intestinal ameba

“…[ 49 50 51 52 ] This association may at least in part be explained by Endolimax being an indicator of fecal contamination, which may often entail co-infection by other organisms capable of causing diarrhea. In a couple of case studies, Endolimax was associated with chronic diarrhea;[ 52 53 54 ] all cases responded well to treatment, and it was not possible to detect other infections except in the study by Shah et al . [ 52 ] where one case was co-infected with Blastocystis .…”

“…In a couple of case studies, Endolimax was associated with chronic diarrhea;[ 52 53 54 ] all cases responded well to treatment, and it was not possible to detect other infections except in the study by Shah et al . [ 52 ] where one case was co-infected with Blastocystis . It is possible that the cysts in the study published by Fitzgerald and O’Farrell[ 53 ] are not Endolimax cysts since they were described as having only one nucleus.…”

Endolimax nana and urticaria

“…In a previous study on pregnant women, carried out in the state of Minas Geiras, Brazil, the percentage was 2% [14]. Although E. nana is considered a non-pathogenic protozoan, it caused rare cases of abdominal pain, diarrhoea (sometimes chronic diarrhoea) [2][3][4][5][6][7][8][9], polyarthritis [9,10] and urticaria [11]. Eosinophilia is rather common [3,15] (8.1% of patients with eosinophilia in the previously cited Czech study) [3].…”

“…Endolimax is transmitted through fecal-oral contamination of food and water [1,2] or by contact with infected animals [2]. Although E. nana is considered a non-pathogenic protozoan, it caused rare cases of abdominal pain, diarrhoea [2][3][4][5][6][7][8][9], polyarthritis [9,10] and urticaria [11]. We describe a case of chronic urticaria associated with E. nana.…”