Human cryptosporidiosis in immunodeficient patients in France (2015–2017)

Cryptosporidium sp. infection in solid organ transplant recipients: A systematic review and meta-analysis

(1) Background: Organ transplant recipients (OTRs) are vulnerable groups at risk of parasitic infections. This systematic review and meta-analysis aimed to evaluate the overall prevalence of Cryptosporidium sp. in OTRs and shed light on this potentially serious complication of organ transplantation. (2) Methods: We systematically searched studies on Cryptosporidium sp. infections in OTRs in four databases (Academia, PubMed, Scopus, and Science Direct). Random effects models were used to calculate pooled prevalence estimates with 95% confidence intervals (CIs). Sub-group and meta-regression analyses were conducted. A quality assessment of the included studies was also performed. (3) Results: Among 876 articles retrieved, 21 were included, accounting for 2,642 OTRs. Twenty studies were cross-sectional in design, of which seven reported data on a comparison group, and one was a retrospective cohort. The pooled prevalence of Cryptosporidium sp. in OTRs was 15% (95% CI: 7.4-24.6). Subgroup analysis revealed that the prevalence of Cryptosporidium sp. infection was higher in adults, symptomatics and developing countries and in studies using only non-molecular methods. However, substantial heterogeneity was reported. Low to moderate heterogeneity was observed in subgroups reporting lower prevalence Cryptosporidium sp. including children (5.8; 95% CI: 2.8-9.6), studies conducted in developed countries (5.8; 95% CI: 3.0-9.4) and studies using both molecular and non-molecular diagnostics (11.4; 95% CI: 6.4-17.4). The majority of the listed research reported low-medium quality scores. (4) Conclusion: Cryptosporidium sp. infection is a significant complication in OTRs with underreported prevalence. Preventive strategies to reduce the burden should include Cryptosporidium sp. routine screening for OTRs, particularly post-transplantation in patients with diarrhea. Additional well-designed research studies are required to determine the extent of the Cryptosporidium sp. burden in OTRs.

Performance of sewage treatment technologies for the removal of Cryptosporidium sp. and Giardia sp.: Toward water circularity

Cryptosporidium sp. and Giardia sp. are parasites that cause diseases in the population. Most of parasite diseases regarding the consumption of drinking water polluted with sewage are caused by Cryptosporidium sp. or Giardia sp. it is because of the incomplete disinfection of the wastewater treatment. Therefore, in this work the removal or inactivation efficiency of different treatment technologies presented by around 40 scientific studies was evaluated, with a view to water circularity. For Cryptosporidium sp., we conclude that the most efficient secondary technologies are aerobic technologies, which remove between 0.00 and 2.17 log units (Ulog), with activated sludge presenting the greatest efficiency, and that the tertiary technologies with the greatest removal are those that use ultrasound, which reach removal values of 3.17 Ulog. In the case of Giardia sp., the secondary technologies with the greatest removal are anaerobic technologies, with values between 0.00 and 3.80 Ulog, and the tertiary technologies with the greatest removal are those that combine filtration with UV or a chemical disinfection agent. Despite the removal values obtained, the greatest concern remains detecting and quantifying the infectious forms of both parasites in effluents; therefore, although the technologies perform adequately, discharge effluents must be monitored with more sensitive techniques, above all aiming for circularity of the treated water in a context of the water scarcity that affects some parts of the world.

Effect of Caging on Cryptosporidium parvum Proliferation in Mice

Cryptosporidiosis is an enteric infection caused by several protozoan species in the genus Cryptosporidium (phylum Apicomplexa). Immunosuppressed mice are commonly used to model this infection. Surprisingly, for a pathogen like Cryptosporidium parvum, which is readily transmitted fecal-orally, mice housed in the same cage can develop vastly different levels of infection, ranging from undetectable to lethal. The motivation for this study was to investigate this phenomenon and assess the association between the severity of cryptosporidiosis and the fecal microbiota. To this aim, the association between severity of cryptosporidiosis and caging (group caged vs. individually caged) and between the microbiota taxonomy and the course of the infection was examined. In contrast to mice caged in groups of four, a majority of mice caged individually did not excrete a detectable level of oocysts. Microbiota α diversity in samples collected between three days prior to infection and one day post-infection was negatively correlated with the severity of cryptosporidiosis, suggesting a causal negative relationship between microbiota diversity and susceptibility to C. parvum.

The implementation of the Kinyoun staining technique in a resource-limited setting is feasible and reveals a high prevalence of intestinal cryptosporidiosis in HIV patients

OBJECTIVES

In resource-limited settings, intestinal Cryptosporidia or coccidian infections are common causes of chronic diarrhoea, but usually remain undiagnosed by routine stool investigation. Here, the addition of the Kinyoun staining technique after stool concentration was evaluated as an easy and inexpensive method for diagnosis of intestinal parasitic infection in HIV-infected patients.

METHODS

This cross-sectional study investigated HIV-infected patients with diarrhoea and randomly selected HIV-infected patients without diarrhoea as controls. Stool samples were examined by wet mount microscopy and Kinyoun staining after stool concentration. Clinical, sociodemographic and behavioural data were collected. Statistical analysis was performed using Chi-squared test and multivariate regression analysis.

RESULTS

In total, 163 participants were included (62.0% female, mean age 38.2 [SD ±10.7] years). Diarrhoea was present in 52.1% (85/163). The prevalence of intestinal parasites was 18.4% (30/163). Cryptosporidia infections were more frequent among patients with diarrhoea (12.9% [11/85] vs. 1.3% [1/78], p=0.005) and in patients with CD4⁺ cell count <200 cells/µL (25.9% [7/27] vs. 3.7% [5/136], p=0.001). Risk factors for intestinal parasitic infections were diarrhoea and the habit of regularly eating uncooked food. Kinyoun staining was necessary for detection of cryptosporidiosis.

CONCLUSION

In our cohort, the prevalence of intestinal parasitic infection was high, especially after additional utilization of Kinyoun staining for detection of Cryptosporidia or intestinal coccidia. Considering its clinical relevance particularly in individuals at risk, the implementation of this technique should be considered in resource-limited settings.

Molecular Detection of Cryptosporidium cuniculus in Rabbits (Oryctolagus cuniculus) from Tenerife, Canary Islands, Spain

Cryptosporidium cuniculus is a zoonotic parasite responsible for cryptosporidiosis cases and outbreaks in both humans and rabbits. Since there are no molecular Cryptosporidium spp. infection data in rabbits (Oryctolagus cuniculus) from Spain, our aim was to gather information about this parasite in wild European rabbits from Tenerife, Canary Islands (Spain). A total of 100 faecal samples were collected from rabbits from eight municipalities of Tenerife. Microscopic analysis showed that 4.0% of the samples presented structures compatible with Cryptosporidium oocyst. A nested polymerase chain reaction (PCR) targeting 18S ribosomal RNA (rRNA) gene fragments was carried out, and sequencing confirmed the identity of C. cuniculus in one sample (1.0%). The sample was successfully subtyped using nested PCR analysis of the 60-kDa glycoprotein (gp60) gene as the subtype VbA26R3. This study confirms the presence of C. cuniculus in wild rabbits from Tenerife, providing new information on the occurrence of this zoonotic parasite. Further studies are required to better understand the epidemiology of Cryptosporidium spp. in wild rabbits in Spain and their possible public health repercussions.

Resolution of Cryptosporidiosis in Transplant Recipients: Review of the Literature and Presentation of a Renal Transplant Patient Treated With Nitazoxanide, Azithromycin, and Rifaximin

Background

Cryptosporidium is a major cause of diarrheal disease worldwide, including chronic disease in malnourished children and patients with acquired immune deficiency syndrome. There are increasing reports of cryptosporidiosis in transplant patients, especially from middle-income countries.

Methods

The literature on treatment of cryptosporidiosis in transplant patients was reviewed and included no controlled trials but only small case series. Nitazoxanide, azithromycin, spiramycin, and combination therapies have been used, but none are consistently efficacious.

Results

We present a case of chronic diarrhea from cryptosporidiosis in a renal transplant patient. His illness resolved with decreasing immunosuppression and treatment with the 3-drug combination of nitazoxanide, azithromycin, and rifaximin.

Conclusions

Although current therapies are not reliably effective in the absence of an effective cellular immune response, combination therapies hold promise for improved responses.

An Update on Zoonotic Cryptosporidium Species and Genotypes in Humans

The enteric parasite, Cryptosporidium is a major cause of diarrhoeal illness in humans and animals worldwide. No effective therapeutics or vaccines are available and therefore control is dependent on understanding transmission dynamics. The development of molecular detection and typing tools has resulted in the identification of a large number of cryptic species and genotypes and facilitated our understanding of their potential for zoonotic transmission. Of the 44 recognised Cryptosporidium species and >120 genotypes, 19 species, and four genotypes have been reported in humans with C. hominis, C. parvum, C. meleagridis, C. canis and C. felis being the most prevalent. The development of typing tools that are still lacking some zoonotic species and genotypes and more extensive molecular epidemiological studies in countries where the potential for transmission is highest are required to further our understanding of this important zoonotic pathogen. Similarly, whole-genome sequencing (WGS) and amplicon next-generation sequencing (NGS) are important for more accurately tracking transmission and understanding the mechanisms behind host specificity.

Occurrence of cryptosporidium parvum IIaA17G1R1 in hospitalized hemato-oncological patients in Slovakia

This study aimed to determine the presence of cryptosporidiosis in immunosuppressed patients hospitalized at the Clinic of Haematology and Oncohaematology in a form of routine screening. Samples were collected from November 2019 to February 2020, when the first wave of the Coronavirus pandemic occurred in Slovakia. A total of 36 samples were collected from patients hospitalized at the Clinic of Haematology and Oncohaematology, both from the open ward and the intensive care unit. For the diagnosis of cryptosporidiosis, a nested PCR targeting the gp60 gene and the SSU rRNA locus was used. From the 36 samples, Cryptosporidium parvum subtype IIaA17G1R1 was diagnosed in 9 patients (7 from the open ward and 2 from the intensive care unit), all hospitalized at the clinic at the same time, in February 2020. The occurrence of the same species and subtype, Cryptosporidium parvum IIaA17G1R1, in 9 patients hospitalized at the same time, both at the open ward and the intensive care unit may suggest a possible transmission occurred at the clinic.

Comparative Performance of Eight PCR Methods to Detect Cryptosporidium Species

Diagnostic approaches based on PCR methods are increasingly used in the field of parasitology, particularly to detect Cryptosporidium. Consequently, many different PCR methods are available, both “in-house” and commercial methods. The aim of this study was to compare the performance of eight PCR methods, four “in-house” and four commercial methods, to detect Cryptosporidium species. On the same DNA extracts, performance was evaluated regarding the limit of detection for both C. parvum and C. hominis specificity and the ability to detect rare species implicated in human infection. Results showed variations in terms of performance. The best performance was observed with the FTD^® Stool parasites method, which detected C. parvum and C. hominis with a limit of detection of 1 and 10 oocysts/gram of stool respectively; all rare species tested were detected (C. cuniculus, C. meleagridis, C. felis, C. chipmunk, and C. ubiquitum), and no cross-reaction was observed. In addition, no cross-reactivity was observed with other enteric pathogens. However, commercial methods were unable to differentiate Cryptosporidium species, and generally, we recommend testing each DNA extract in at least triplicate to optimize the limit of detection.

High Diversity of Cryptosporidium Species and Subtypes Identified in Cryptosporidiosis Acquired in Sweden and Abroad

The intestinal protozoan parasite Cryptosporidium is an important cause of diarrheal disease worldwide. The aim of this study was to expand the knowledge on the molecular epidemiology of human cryptosporidiosis in Sweden to better understand transmission patterns and potential zoonotic sources. Cryptosporidium-positive fecal samples were collected between January 2013 and December 2014 from 12 regional clinical microbiology laboratories in Sweden. Species and subtype determination was achieved using small subunit ribosomal RNA and 60 kDa glycoprotein gene analysis. Samples were available for 398 patients, of whom 250 (63%) and 138 (35%) had acquired the infection in Sweden and abroad, respectively. Species identification was successful for 95% (379/398) of the samples, revealing 12 species/genotypes: Cryptosporidium parvum (n = 299), C. hominis (n = 49), C. meleagridis (n = 8), C. cuniculus (n = 5), Cryptosporidium chipmunk genotype I (n = 5), C. felis (n = 4), C. erinacei (n = 2), C. ubiquitum (n = 2), and one each of C. suis, C. viatorum, C. ditrichi, and Cryptosporidium horse genotype. One patient was co-infected with C. parvum and C. hominis. Subtyping was successful for all species/genotypes, except for C. ditrichi, and revealed large diversity, with 29 subtype families (including 4 novel ones: C. parvum IIr, IIs, IIt, and Cryptosporidium horse genotype Vic) and 81 different subtypes. The most common subtype families were IIa (n = 164) and IId (n = 118) for C. parvum and Ib (n = 26) and Ia (n = 12) for C. hominis. Infections caused by the zoonotic C. parvum subtype families IIa and IId dominated both in patients infected in Sweden and abroad, while most C. hominis cases were travel-related. Infections caused by non-hominis and non-parvum species were quite common (8%) and equally represented in cases infected in Sweden and abroad.

Use-case scenarios for an anti-Cryptosporidium therapeutic

Cryptosporidium is a widely distributed enteric parasite that has an increasingly appreciated pathogenic role, particularly in pediatric diarrhea. While cryptosporidiosis has likely affected humanity for millennia, its recent "emergence" is largely the result of discoveries made through major epidemiologic studies in the past decade. There is no vaccine, and the only approved medicine, nitazoxanide, has been shown to have efficacy limitations in several patient groups known to be at elevated risk of disease. In order to help frontline health workers, policymakers, and other stakeholders translate our current understanding of cryptosporidiosis into actionable guidance to address the disease, we sought to assess salient issues relating to clinical management of cryptosporidiosis drawing from a review of the literature and our own field-based practice. This exercise is meant to help inform health system strategies for improving access to current treatments, to highlight recent achievements and outstanding knowledge and clinical practice gaps, and to help guide research activities for new anti-Cryptosporidium therapies.

Phenotypic screening techniques for Cryptosporidium drug discovery

Introduction: Two landmark epidemiological studies identified Cryptosporidium spp. as a significant cause of diarrheal disease in pediatric populations in resource-limited countries. Notably, nitazoxanide is the only approved drug for treatment of cryptosporidiosis but shows limited efficacy. As a result, many drug discovery efforts have commenced to find improved treatments. The unique biology of Cryptosporidium presents challenges for traditional drug discovery methods, which has inspired new assay platforms to study parasite biology and drug screening. Areas covered: The authors review historical advancements in phenotypic-based assays and techniques for Cryptosporidium drug discovery, as well as recent advances that will define future drug discovery. The reliance on phenotypic-based screens and repositioning of phenotypic hits from other pathogens has quickly created a robust pipeline of potential cryptosporidiosis therapeutics. The latest advances involve new in vitro culture methods for oocyst generation, continuous culturing capabilities, and more physiologically relevant assays for testing compounds. Expert opinion: Previous phenotypic screening techniques have laid the groundwork for recent cryptosporidiosis drug discovery efforts. The resulting improved methodologies characterize compound activity, identify, and validate drug targets, and prioritize new compounds for drug development. The most recent improvements in phenotypic assays are poised to help advance compounds into clinical development.

Epidemiology of Cryptosporidiosis in France from 2017 to 2019

Cryptosporidiosis is currently recognized worldwide as a leading cause of moderate to severe diarrhea. In Europe, large water- and foodborne outbreaks have been reported, highlighting the widespread distribution of the parasite and its important health impact. Surveillance networks have been progressively set up and the aim of this study was to present recent epidemiological data obtained in France from 2017 to 2019 by the National Reference Center-Expert Laboratory of cryptosporidiosis (Centre National de Référence-Laboratoire Expert cryptosporidioses CNR-LE). Data were obtained from online reports of volunteer network participants and stools were sent to the CNR-LE for species identification and GP60 genotyping. During this period, data from 750 online reports were available. Cryptosporidiosis occurred predominantly in young children (<5 years old) and in young adults, especially during late summer. Most patients were immunocompetent (60%), and deaths were reported only in immunocompromised patients. Cryptosporidium parvum was largely predominant (72% of cases) over C. hominis (24%) and some other uncommon species. C. parvum GP60 subtypes IIa and IId were the most represented, which suggests frequent zoonotic transmission. For C. hominis, subtypes IbA10G2 and IaA22R2 were predominant.

Cryptosporidiosis after treatment with fingolimod: a case report and pharmacovigilance review

Background

Cryptosporidium sp. are common intracellular parasites responsible of severe diarrhea in T-cell-immunocompromised patients. We report the first case of a woman who contracted cryptosporidiosis after treatment with fingolimod, a drug labeled for multiple sclerosis and responsible for marked lymphopenia.

Case presentation

A 60-year-old woman was admitted for abdominal pain diarrhea and fever. The patient suffered from multiple sclerosis and had been treated with fingolimod from august 2017 to september 2018 time of occurrence of the first digestive symptoms. Stool culture was negative but parasitological examination was positive for Cryptosporidium sp. Blood biological examination profound lymphopenia of 240/mm³ [17 CD4/mm³ (7%) and 32 CD8/mm³ (14%)]. Fingolimod was stopped, and the patient was put on nitazoxanide 500 mg bid for 7 days. The diarrhea resolved and no relapse was observed. Six other cases were found in the Pharmacovigilance database.

Conclusion

Physicians should be aware of this association and screen for Cryptosporidium in cases of diarrhea in patients treated with fingolimod. Patients should be aware of this risk and advise to take appropriate measures to avoid such contamination.

Single and multiple detections of foodborne pathogens by gold nanoparticle assays

A late detection of pathogenic microorganisms in food and drinking water has a high potential to cause adverse health impacts in those who have ingested the pathogens. For this reason there is intense interest in developing precise, rapid and sensitive assays that can detect multiple foodborne pathogens. Such assays would be valuable components in the campaign to minimize foodborne illness. Here, we discuss the emerging types of assays based on gold nanoparticles (GNPs) for rapidly diagnosing single or multiple foodborne pathogen infections. Colorimetric and lateral flow assays based on GNPs may be read by the human eye. Refractometric sensors based on a shift in the position of a plasmon resonance absorption peak can be read by the new generation of inexpensive optical spectrometers. Surface-enhanced Raman spectroscopy and the quartz microbalance require slightly more sophisticated equipment but can be very sensitive. A wide range of electrochemical techniques are also under development. Given the range of options provided by GNPs, we confidently expect that some, or all, of these technologies will eventually enter routine use for detecting pathogens in food. This article is categorized under: Diagnostic Tools > Biosensing.