<i>Septata intestinalis</i> frequently isolated from stool of AIDS patients with a new cultivation method

Gool, Tom van; Canning, Elizabeth U.; Gilis, Henk; Weerman, Marius A. van den Bergh; Schattenkerk, J. K. M. Eeftinck; Dankert, J.

doi:10.1017/s0031182000078318

Cited by 70 publications

(48 citation statements)

References 23 publications

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“…These techniques include traditional "growth-no growth" models, enumeration of infective foci in stained cell monolayers, and spore germination to assess the effects of laboratory disinfectants or drugs on the subsequent growth and infective capabilities of microsporidia (9,17,21,32,36,42,44,51,53,56,59). More recently, vital dye loading and subsequent scanning confocal microscopy have been used (37).…”

Section: Discussionmentioning

confidence: 99%

A Spore Counting Method and Cell Culture Model for Chlorine Disinfection Studies of Encephalitozoon syn. Septata intestinalis

Wolk

Johnson

Rice

et al. 2000

Appl Environ Microbiol

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The microsporidia have recently been recognized as a group of pathogens that have potential for waterborne transmission; however, little is known about the effects of routine disinfection on microsporidian spore viability. In this study, in vitro growth of Encephalitozoon syn. Septata intestinalis, a microsporidium found in the human gut, was used as a model to assess the effect of chlorine on the infectivity and viability of microsporidian spores. Spore inoculum concentrations were determined by using spectrophotometric measurements (percent transmittance at 625 nm) and by traditional hemacytometer counting. To determine quantitative dose-response data for spore infectivity, we optimized a rabbit kidney cell culture system in 24-well plates, which facilitated calculation of a 50% tissue culture infective dose (TCID 50 ) and a minimal infective dose (MID) for E. intestinalis. The TCID 50 is a quantitative measure of infectivity and growth and is the number of organisms that must be present to infect 50% of the cell culture wells tested. The MID is as a measure of a system's permissiveness to infection and a measure of spore infectivity. A standardized MID and a standardized TCID 50 have not been reported previously for any microsporidian species. Both types of doses are reported in this paper, and the values were used to evaluate the effects of chlorine disinfection on the in vitro growth of microsporidia. Spores were treated with chlorine at concentrations of 0, 1, 2, 5, and 10 mg/liter. The exposure times ranged from 0 to 80 min at 25°C and pH 7. MID data for E. intestinalis were compared before and after chlorine disinfection. A 3-log reduction (99.9% inhibition) in the E. intestinalis MID was observed at a chlorine concentration of 2 mg/liter after a minimum exposure time of 16 min. The log 10 reduction results based on percent transmittance-derived spore counts were equivalent to the results based on hemacytometer-derived spore counts. Our data suggest that chlorine treatment may be an effective water treatment for E. intestinalis and that spectrophotometric methods may be substituted for labor-intensive hemacytometer methods when spores are counted in laboratory-based chlorine disinfection studies.

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Section: Discussionmentioning

confidence: 99%

A Spore Counting Method and Cell Culture Model for Chlorine Disinfection Studies of Encephalitozoon syn. Septata intestinalis

Wolk

Johnson

Rice

et al. 2000

Appl Environ Microbiol

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“…E. intestinalis, E. hellem, and E. cuniculi were cultured in RK 13 rabbit kidney cell monolayers (39). Spores were harvested by centrifugation, washed with phosphate-buffered saline (PBS), resuspended in PBS, and counted microscopically.…”

Section: Methodsmentioning

confidence: 99%

“…Infections with microsporidia in immunocompetent individuals such as travelers have also been described (31,35). In HIV-infected patients, E. bieneusi and E. intestinalis can cause a severe, persistent diarrhea, and the species have frequently been isolated from stool specimens (11,16,17,34,39). Furthermore, Encephalitozoon species are associated with rhinosinusitis, keratoconjunctivitis, nephritis, hepatitis, and disseminated infections (9,17,18,24,29).…”

mentioning

confidence: 99%

Detection and Identification of Enterocytozoon bieneusi and Encephalitozoon Species in Stool and Urine Specimens by PCR and Differential Hybridization

et al. 2005

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Several species of microsporidia can cause disease in humans in both immunocompromised and immunocompetent individuals. Enterocytozoon bieneusi and Encephalitozoon intestinalis are most commonly associated with chronic diarrhea. All Encephalitozoon species, including E. intestinalis, E. hellem, and E. cuniculi, also cause disseminated infections. As distinctive treatment options are available for the different genera, identification is clinically important. We evaluated a PCR with primers directed to a conserved region of the small subunit rRNA gene of microsporidia. Hybridization with a generic microsporidium probe and specific probes for each of the four different species was used for identification. Probes were labeled with ruthenium and detected by electrochemiluminescence. The sensitivity of the assay was tested with plasmids containing the region of interest from each of the four different species and Vittaforma corneae as a control. In addition, the assay was tested with feces spiked with cultured spores from each of the three Encephalitozoon species and V. corneae. An analytical sensitivity of 3.5 ؋ 10 2 to 3.5 ؋ 10 3 spores per g of feces, corresponding to 17 to 170 gene copies per PCR, was found, which is several orders of magnitude more sensitive than microscopy after Uvitex 2B fluorescent staining. Stool samples from 22 microscopically diagnosed patients and from 61 uninfected controls were evaluated, showing a sensitivity of at least 95% and a specificity of 100% compared to microscopy. The method was further tested by spiking urine samples with spores of the different Encephalitozoon species.

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“…(i) Parasites and cultures. The strain of E. intestinalis used in this study, kindly provided by T. Van Gool (Amsterdam, The Netherlands), was isolated from the stools of an HIV-infected patient (17). It was identified by electron microscopy and specific PCR (5) and maintained in tissue culture with the human glioblastoma cell line U-373-MG (ATCC HTB17) (14).…”

Section: Methodsmentioning

confidence: 99%

Development of a Real-Time PCR Assay for Quantitative Detection of Encephalitozoon intestinalis DNA

Menotti¹,

Cassinat²,

Sarfati³

et al. 2003

J Clin Microbiol

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A new real-time PCR assay for quantitation of Encephalitozoon intestinalis DNA was developed which used a TaqMan fluorescent probe for specific detection. Serial dilutions of E. intestinalis spore suspensions obtained from tissue culture were used as external standards. The detection limit of the technique was 20 spores per ml, with a good interassay reproducibility (coefficient of variation of 7.1% for the suspension containing 20 spores/ml, 5.0% for the suspension containing 75 spores/ml and below 3.5% for higher concentrations). Quantitative detection of E. intestinalis DNA was similar whether the serial dilutions of spores were made in distilled water or in a stool suspension, allowing the use of the assay for stool specimens. The assay was then applied to 14 clinical specimens from 8 immunocompromised patients with proven E. intestinalis infection. The quantitation of the parasitic burden was achieved in stools, blood, urine, tissue biopsies, and bronchopulmonary specimens. The highest parasitic burdens were noted in stools, urine, and bronchopulmonary specimens, reaching 10 5 to 10 6 spores/g or ml. Dissemination of the infection was also evidenced in some patients by demonstration of E. intestinalis DNA in blood and serum. We conclude that real-time PCR is a valuable tool for quantitation of E. intestinalis burden in clinical specimens.

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Septata intestinalis frequently isolated from stool of AIDS patients with a new cultivation method

Cited by 70 publications

References 23 publications

A Spore Counting Method and Cell Culture Model for Chlorine Disinfection Studies of Encephalitozoon syn. Septata intestinalis

A Spore Counting Method and Cell Culture Model for Chlorine Disinfection Studies of Encephalitozoon syn. Septata intestinalis

Detection and Identification of Enterocytozoon bieneusi and Encephalitozoon Species in Stool and Urine Specimens by PCR and Differential Hybridization

Development of a Real-Time PCR Assay for Quantitative Detection of Encephalitozoon intestinalis DNA

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