Evaluation of gram-chromotrope kinyoun staining technique: its effectiveness in detecting microsporidial spores in fecal specimens

Intestinal microsporidiosis among HIV/AIDS patients receiving antiretroviral therapy in Sana'a city, Yemen: first report on prevalence and predictors

Background

Intestinal microsporidiosis is an opportunistic infection associated with persistent diarrhea among HIV/AIDS patients. In Yemen, however, its epidemiology is unknown. Therefore, this study determined its prevalence and predictors among HIV/AIDS patients receiving antiretroviral therapy (ART) in Sana’a city, the capital of Yemen.

Methods

This cross-sectional study included 402 patients receiving ART at Al-Jomhori Educational Hospital in Sana’a from November 2019 to December 2020. Data about demographics, clinical characteristics and risk factors were collected using a pre-designed questionnaire. Stool samples were collected and examined for microsporidian spores using the Gram-chromotrope Kinyoun staining. Blood samples were also collected and used for CD4 cell counting by flow cytometry. Univariate analysis was used to test the association of patients’ characteristics and risk factors with intestinal microsporidiosis. Multivariable logistic regression was then used to identify the independent predictors of infection. Statistical significance was considered at P-values < 0.05.

Results

Intestinal microsporidiosis was prevalent among 14.2% (57/402) of HIV/AIDS patients and was significantly associated with diarrhea (OR 3.4, 95% CI 1.7–6.6; P = 0.001). The significant independent predictors of infection were < 200 CD4 cells/µl (AOR 3.2, 95% CI 1.5–6.9; P = 0.003), not washing hands after contacting soil (AOR 2.5, 95% CI 1.1–5.4; P = 0.026) and before eating (AOR 3.1, 95% CI 1.5–6.4; P = 0.003), eating unwashed raw produce (AOR 2.5, 95% CI 1.2–5.3; P = 0.017) and absence of indoor latrines (AOR 6.2, 95% CI 1.5–25.9; P = 0.012).

Conclusions

The prevalence of intestinal microsporidiosis among HIV/AIDS patients in Sana'a is high and comparable to that reported from several other countries, being prevalent among approximately 14.0% of patients and significantly associated with diarrhea. It could be predicted among patients who have < 200 CD4 cells/µl, have poor hand hygiene after contacting soil and before eating, usually eat unwashed raw produce, or do not possess indoor latrines. Large-scale studies on its epidemiology and predictors among HIV/AIDS patients across the country are warranted.

Risk factors associated with cat parasites in a feline medical center

Objectives

The present study was carried out to evaluate the risk factors for and presence of intestinal parasites in cats at the feline hospital ‘CEME Gatos’, Mexico City.

Methods

In total, 528 fecal samples from domestic cats were collected and analyzed in order to diagnose enteroparasites.

Results

The parasite with the highest prevalence was Giardia species (21.97%), followed by Cryptosporidium species (7%), Toxocara cati (6.45%), Cystoisospora species (5.11%) and Dipylidium caninum (0.76%). One hundred and twenty-one cats (55.50%) were infected with a single parasite, 80 (36.69%) were infected with two and 17 (14.04%) were infected with three parasites. The results of the prevalence study showed that a liquid consistency of feces was associated with the presence of Giardia species, whereas age <7 months and mucus in the stool were factors associated with the prevalence of Cystoisospora species. Regarding T cati, the associated risk factors were age <7 months, being male, contact with other animal species and access to the outdoors. The last factor was strongly associated with the presence of T cati (eight times more likely) in outdoor cats’ feces. Brushing frequency was also an associated factor: T cati was present in cats that were never brushed. The results of the analysis of cats infected with D caninum showed that interaction with other species was a risk factor for infection.

Conclusions and relevance

Age <7 months, mucus in feces, living with other animal species, outdoor access and frequency of brushing are risk factors for the presence of parasites.

Enterocytozoon bieneusi of animals-With an 'Australian twist'

Enterocytozoon bieneusi is a microsporidian microorganism that causes intestinal disease in animals including humans. E. bieneusi is an obligate intracellular pathogen, typically causing severe or chronic diarrhoea, malabsorption and/or wasting. Currently, E. bieneusi is recognised as a fungus, although its exact classification remains contentious. The transmission of E. bieneusi can occur from person to person and/or animals to people. Transmission is usually via the faecal-oral route through E. bieneusi spore-contaminated water, environment or food, or direct contact with infected individuals. Enterocytozoon bieneusi genotypes are usually identified and classified by PCR-based sequencing of the internal transcribed spacer region (ITS) of nuclear ribosomal DNA. To date, ~600 distinct genotypes of E. bieneusi have been recorded in ~170 species of animals, including various orders of mammals and reptiles as well as insects in >40 countries. Moreover, E. bieneusi has also been found in recreational water, irrigation water, and treated raw- and waste-waters. Although many studies have been conducted on the epidemiology of E. bieneusi, prevalence surveys of animals and humans are scant in some countries, such as Australia, and transmission routes of individual genotypes and related risk factors are poorly understood. This article/chapter reviews aspects of the taxonomy, biology and epidemiology of E. bieneusi; the diagnosis, treatment and prevention of microsporidiosis; critically appraises the naming system for E. bieneusi genotypes as well as the phylogenetic relationships of these genotypes; provides new insights into the prevalence and genetic composition of E. bieneusi populations in animals in parts of Australia using molecular epidemiological tools; and proposes some areas for future research in the E. bieneusi/microsporidiosis field.

Outpatient Antibiotic Consumption Fluctuations in a View of Unreasonable Antibacterial Therapy

Unreasonable antibacterial therapy is suspected to be the main reason of emergence of multi-resistant bacteria. The connection between seasonal variability of antibiotic use and reasonable antibacterial therapy has been described. We examined the issue basing on the data obtained from the primary care system in Szczecin (Poland) in order to verify the situation in this region of Central Europe. Increase in antibiotic consumption in a viral infection season was proved to be statistically significant. Statistically significant differences in various drug forms dispensation were also observed. Increased consumption of antibiotics in seasons of influenza-like illnesses might be connected with a lack of proper diagnostics or numerous cases of bacterial co-infections.

Loop-mediated isothermal amplification for rapid molecular detection of Enterocytozoon bieneusi in faecal specimens

A loop-mediated isothermal amplification (LAMP) assay was developed to detect Enterocytozoon bieneusi DNA for the first time from human faecal specimens. Four primers specific for Enterocytozoon bieneusi were designed corresponding to small subunit rRNA gene sequences and tested on 100 human faecal specimens. Thirty-nine of the faecal specimens (39%) were confirmed positive for Enterocytozoon bieneusi by LAMP compared with 33% by PCR and 32% by light microscopy. LAMP yielded 94% sensitivity and 88% specificity compared with microscopy (sensitivity 48%, specificity 76%). No significant differences in positive detection of Enterocytozoon bieneusi were found among the three methods (P>0.05). However, LAMP has shown a substantial agreement with PCR (κ = 0.78) and fair agreement was demonstrated between microscopy and PCR (κ = 0.25). In conclusion, the LAMP assay proved to be useful as a simplified, rapid, sensitive and specific alternative molecular screening tool in the diagnosis of Enterocytozoon bieneusi in faecal specimens

New insights of Microsporidial infection among asymptomatic aboriginal population in Malaysia

Background

Studies on microsporidial infection mostly focus on immunodeficiency or immunosuppressive individuals. Therefore, this cross-sectional study describes the prevalence and risk factors of microsporidiosis among asymptomatic individuals in Malaysia.

Methods/Findings

Four hundred and forty seven stool samples were collected and examined for microsporidia after staining with Gram-chromotrope Kinyoun. Demographic, socioeconomic, environmental, and behavioral information were collected by using a pre-tested questionnaire. Overall, 67 (15%) samples were positive for microsporidia. The prevalence of infection was significantly higher among individuals aged more than 15 years compared to those aged <15 years (OR = 1.97, 95% CI = 1.08, 3.62; P = 0.028). Furthermore, logistic regression analysis confirmed that the presence of other family members infected with microsporidia (OR = 8.45; 95% CI = 4.30, 16.62; P<0.001) and being a consumer of raw vegetables (OR = 2.05; 95% CI = 1.15, 3.66; P = 0.016) were the significant risk factors of this infection.

Conclusions

These findings clearly show that exposure to microsporidia is common among Aboriginal population. Further studies using molecular approach on microsporidia isolates from asymptomatic individuals is needed to determine species-specific. The risk factors associated with microsporidiosis will help in identifying more clearly the sources of the infection in the environment that pose a risk for transmission so that preventive strategies can be implemented.

Microsporidiosis: not just in AIDS patients

PURPOSE OF REVIEW

Microsporidia have emerged as causes of opportunistic infections associated with diarrhea and wasting in AIDS patients. This review describes recent reports of microsporidiosis in HIV-infected individuals and the growing awareness of microsporidiosis in non-HIV-infected populations.

RECENT FINDINGS

Microsporidia were only rarely recognized as causes of disease in humans until the AIDS pandemic. Implementation of combination antiretroviral therapy (cART) to curtail HIV replication and restore immune status drastically reduced the occurrence of opportunistic infections, including those due to microsporidia, in HIV-infected individuals. In developing countries where cART is not always accessible, microsporidiosis continues to be problematic. Improvement of diagnostic methods over the previous 25 years led to identification of several new species of microsporidia, many of which disseminate from enteric to systemic sites of infection and contribute to some unexpected lesions. Among non-HIV-infected but immune-suppressed individuals, microsporidia have infected organ transplant recipients, children, the elderly, and patients with malignant disease and diabetes. In otherwise healthy immune-competent HIV seronegative populations, self-limiting diarrhea occurred in travelers and as a result of a foodborne outbreak associated with contaminated cucumbers. Keratitis due to microsporidiosis has become problematic and a recent longitudinal evaluation demonstrated that non-HIV-infected individuals seropositive for microsporidia who had no clinical signs continued to intermittently shed organisms in feces and urine.

SUMMARY

Greater awareness and implementation of better diagnostic methods are demonstrating that microsporidia contribute to a wide range of clinical syndromes in HIV-infected and non-HIV-infected people. As such, microsporidia should be considered in differential diagnoses if no other cause can be defined.