Prevalence of microsporidia in healthy individuals and immunocompetent patients with acute and chronic diarrhea

Abstract

Unexpectedly, a high prevalence of microsporidia was found in immunocompetent individuals in our region. There was no relationship between positivity for microsporidia and the presence of symptoms, due to higher rates both in solid stools and in healthy subjects. The parasite score was the same in all groups. Our results indicate that there is high exposure to microsporidia in immunocompetent subjects in our region. Natural reservoirs and environmental sources of microsporidia should be determined to design strategies for effective prevention of transmission.

Microsporidiosis in Vertebrate Companion Exotic Animals

“…Chitin-binding fluorochromes [ 12 , 22 , 23 ], chromotrope stains [ 21 ], modified trichrome stain, and Giemsa stain [ 21 ] can also be used to stain microsporidial spores on smears and stool samples, which has been demonstrated in humans [ 22 ]. Notably, fluorescent stains, such as the Luna calcofluor stain, can be used since microsporidian spores contain chitin, but these stains require immunofluorescence microscopy and may lead to false positives since other fungal spores also fluoresce with these stains [ 24 ]. Molecular diagnostic techniques include PCR of the small subunit rRNA gene using PMP1 and PMP2 primers [ 25 , 26 ].…”

“…Molecular diagnostic techniques include PCR of the small subunit rRNA gene using PMP1 and PMP2 primers [ 25 , 26 ]. It is challenging to determine the actual prevalence of microsporidia infection in a population as shedding is typically intermittent [ 24 ] and transit of the fungi through the feces cannot be differentiated from digestive infection based on fecal detection. Of note, the intensity of fecal shedding, and thus the sensibility of fecal screening, has been correlated with severity of infection by intestinal microsporida in humans but has not been correlated with the occurrence of diarrhea [ 27 ].…”

“…A recent study involving more than 200 patients investigated fecal detection of microsporidia in healthy humans and immunocompetent patients presenting with diarrhea: interestingly, the prevalence of microsporidia was higher in the healthy group with 45% of healthy patients shedding microsporidia [ 24 ]. This suggests that digestive microsporidia are often asymptomatic in humans [ 20 ].…”

A large collection of novel nematode-infecting microsporidia and their diverse interactions withC. elegansand other related nematodes

“…Interest in these organisms started 150 years ago when researchers, especially Louis Pasteur, studied silkworm disease that was caused by a microsporidian species later named Nosema bombycis [3]. In the past decades, microsporidia have attracted more attention when they were revealed to be a cause of diarrhea in immunocompromised patients and were further demonstrated to have a high prevalence in some areas in immunocompetent patients and healthy individuals [4][5][6].…”