scholarly journals Improved Cryptosporidium case findings using immunofluorescent microscopy on concentrated stool

2021 ◽  
Vol 22 (2) ◽  
pp. 300-303
Author(s):  
D. Cox ◽  
F.J.L. Robberts
Keyword(s):  
Diagnostic Yield ◽  
Fluorescent Microscopy ◽  
Simultaneous Detection ◽  
Microbiological Analysis ◽  
Diagnostic Laboratory ◽  
Wet Mount ◽  
Cryptosporidium Oocysts ◽  
Stool Samples ◽  
Stool Specimens ◽  
Positive Results

Background: Diarrhoea is a major cause of morbidity in Cape Town, South Africa, and mortality is attributed to a failure to recognize the severity of the condition. Cryptosporidium and Giardia are increasingly recognized as important causes of diarrhoea in Africa however, suboptimal diagnostic techniques may lead to underappreciation of their significance. Our objectives are to compare the diagnostic yield of direct immunofluorescent antigen (DFA) microscopy on concentrated stool samples for Cryptosporidium and Giardia, with the current approach of wet mount microscopy for Giardia and auramine fluorescent stain for Cryptosporidium on unconcentrated stool.Methodology: Stool specimens (n=104) received at our hospital laboratory for routine microbiological investigations were used for the study. Direct wet-mount auramine-phenol fluorescent microscopy (auramine) detection of Cryptosporidium oocysts and wet mount iodine microscopy for Giardia detection, were performed on unconcentrated stool samples, while DFA stain for simultaneous detection of Cryptosporidium and Giardia was performed on sodium-acetate formalin concentrated stool samples. The diagnostic yields of the tests were compared using the MEDCALC® version 18.0Results: Of the 104 stool specimens received for microbiological analysis, only 66 (63.5%) had specific Cryptosporidium requests while 38 (36.5%) had no Cryptosporidium specific requests. Of the 66 specimens, 9 (13.6%) were positive for Cryptosporidium oocysts with DFA while only 1 (1.5%) was positive with auramine staining (p=0.013). The one auramine-positive specimen was also positive by DFA. Auramine stain microscopy gave a sensitivity of 11.1% (95%CI: 0.28-48.25%) and specificity of 100% (95%CI: 93.7%-100%) when compared to DFA. Of the 38 stool specimens without specific Cryptosporidium request, DFA yielded 5 (13.2%) additional positive results. Taken together, Cryptosporidium was detected in 14/104 (13.5%; 95%CI: 8.36–21.7%) specimens and only 1 of 14 (7.1%) specimens with the current routine laboratory testing approach. Giardia was detected by DFA in 3/104 (0.9%) specimens, while direct iodine wet mount microscopy did not yield any positive results (0%). All 3 Giardia-positive specimens had Cryptosporidium oocysts detected by DFA.Conclusion: These data suggest that a large proportion of Cryptosporidium cases remain undetected by the laboratory due to suboptimal testing methods, and failure by clinicians to specifically request for Cryptosporidium detection. There is need to periodically assess the effectiveness of diagnostic microbiology laboratory approaches to diarrhoea, and access to improved diagnostic laboratory techniques will contribute to more accurate differential diagnosis and a broadened understanding of local aetiology of diarrhoea diseases in Africa. Keywords: Cryptosporidium, Giardia, diarrhoea, stool concentration, DFA, microscopy French Title: Amélioration des découvertes de cas de Cryptosporidium à l'aide de la microscopie immunofluorescente sur des selles concentrées Contexte: La diarrhée est une cause majeure de morbidité au Cap, en Afrique du Sud, et la mortalité est attribuée à l'incapacité de reconnaître la gravité de la maladie. Cryptosporidium et Giardia sont de plus en plus reconnus comme des causes importantes de diarrhée en Afrique, cependant, des techniques de diagnostic sous-optimales peuvent conduire à une sous-estimation de leur importance. Nos objectifs sont de comparer le rendement diagnostique de la microscopie à antigène immunofluorescent direct (DFA) sur des échantillons de selles concentrées pour Cryptosporidium et Giardia, avec l'approche actuelle de la microscopie à montage humide pour Giardia et la coloration fluorescente auramine pour Cryptosporidium sur des selles non concentrées.Méthodologie: Des échantillons de selles (n=104) reçus au laboratoire de notre hôpital pour des examens microbiologiques de routine ont été utilisés pour l'étude. La détection directe par microscopie fluorescente auramine-phénol à montage humide (auramine) des oocystes de Cryptosporidium et la microscopie à l'iode à montage humide pour la détection de Giardia, ont été effectuées sur des échantillons de selles non concentrées, tandis que la coloration DFA pour la détection simultanée de Cryptosporidium et de Giardia a été réalisée sur de l'acétate de sodium formaline concentré échantillons de selles. Les rendements diagnostiques des tests ont étécomparés à l'aide de MEDCALC® version 18.0Résultats: Sur les 104 échantillons de selles reçus pour l'analyse microbiologique, seuls 66 (63,5%) avaient des demandes spécifiques de Cryptosporidium tandis que 38 (36,5%) n'avaient pas de demandes spécifiques de Cryptosporidium. Sur les 66 échantillons, 9 (13,6%) étaient positifs pour les oocystes de Cryptosporidium avec DFA tandis que seulement 1 (1,5%) était positif avec coloration à l'auramine (p=0,013). Le seul échantillon positif à l'auramine était également positif au DFA. La microscopie à l'auramine a donné une sensibilité de 11,1% (IC 95%: 0,28-48,25%) et une spécificité de 100% (IC 95%: 93,7% -100%) par rapport au DFA. Sur les 38 échantillons de selles sans demande spécifique de Cryptosporidium, le DFA a donné 5 (13,2%) résultats positifs supplémentaires. Pris ensemble, Cryptosporidium a été détecté dans 14/104 (13,5%; IC à 95%: 8,36–21,7%) et seulement 1 des 14 échantillons (7,1%) avec l'approche actuelle des tests de routine en laboratoire. Giardia a été détecté par DFA dans 3/104 (0,9%) échantillons, tandis que la microscopie directe à l'iode sur monture humide n'a donné aucun résultat positif (0%). Les 3 échantillons positifs à Giardia avaient des oocystes deCryptosporidium détectés par DFA.Conclusion: Ces données suggèrent qu'une grande proportion des cas de Cryptosporidium ne sont pas détectés par le laboratoire en raison de méthodes de test sous-optimales et de l'échec des cliniciens à demander spécifiquement la détection de Cryptosporidium. Il est nécessaire d'évaluer périodiquement l'efficacité des approches de laboratoire de microbiologie diagnostique pour la diarrhée, et l'accès à des techniques de laboratoire de diagnostic améliorées contribuera à un diagnostic différentiel plus précis et à une compréhension élargie de l'étiologie locale des maladies diarrhéiques en Afrique. Mots clés: Cryptosporidium, Giardia, diarrhée, concentration des selles, DFA, microscopie

scholarly journals Diagnostic Accuracy of Four Commercial Triplex Immunochromatographic Tests for Rapid Detection of Rotavirus, Adenovirus, and Norovirus in Human Stool Samples

2020 ◽  
Vol 59 (1) ◽  
pp. e01749-20
Author(s):  
Jérôme Kaplon ◽  
Lucie Théry ◽  
Maxime Bidalot ◽  
Nadège Grangier ◽  
Jean Frappier ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Rapid Detection ◽  
Simultaneous Detection ◽  
High Sensitivity ◽  
High Specificity ◽  
Species Sensitivity ◽  
Routine Diagnosis ◽  
Stool Samples ◽  
Stool Specimens ◽  
Human Stool

ABSTRACTNoroviruses (NoV), rotaviruses (RVA), and adenoviruses (AdV) are the main viral agents responsible for acute gastroenteritis (AGE) in humans. We aimed to determine the diagnostic accuracy of four commercial immunochromatographic tests (ICTs) intended for the rapid and simultaneous detection of these three pathogens. Diagnostic accuracy of bioNexia Noro/Rota-Adeno (bioMérieux), Immunoquick NoRotAdeno (Biosynex), Rota+Adeno+Noro combo card (CerTest Biotec), and Rida Quick Rota/Adeno/Noro Combi (R-Biopharm) ICTs was assessed retrospectively using a collection of 160 stool specimens (including 43 RVA-, 47 AdV-, and 42 NoV-positive samples) from French patients with AGE and using molecular methods as the reference standard. For RVA, the four ICTs demonstrated similar high sensitivity (93%) and excellent specificity (97.4 to 100%). For AdV, the four ICTs demonstrated similar poor sensitivity (54.3 to 58.7%) but excellent specificity (95.5 to 100%). They performed the best in AdV-F species (sensitivity, 80.8 to 84.6%) and worst in AdV non-F species (sensitivity, 22.2 to 27.8%). For NoV, the Rida Quick Rota/Adeno/Noro combi ICT exhibited high sensitivity (87.5%), but the sensitivity of the three others was poor (42.5 to 47.5%). The four ICTs exhibited high specificity (96.6 to 99.1%). Diagnostic accuracy was genogroup dependent. When we tested genogroup I NoV, the Rida Quick Rota/Adeno/Noro Combi ICT presented high sensitivity (90%), while the three other ICTs presented poor sensitivity (10 to 30%); when we tested genogroup II NoV, sensitivity was similar for the four ICTs (65 to 85%). In conclusion, the four ICTs are suitable first-line tests for the rapid diagnosis of RVA infections. The four ICTs are not suitable for the routine diagnosis of AdV infections but could provide a rapid response in case of positivity, notably in the context of AGE. Only the Rida Quick Rota/Adeno/Noro Combi ICT is suitable for the rapid detection of NoV, while the sensitivity for the detection of genogroup I NoV needs to be improved for the 3 other ICTs before being implemented in the routine diagnosis of NoV.

scholarly journals Evaluation of the Diagnostic Utility of Geohelminths from Environmental and Stool Samples in Nnewi Metropolis

2021 ◽  
pp. 34-41
Author(s):  
Chioma Maureen Obi ◽  
Anikpe Chinwoke Akunna ◽  
Ifeanyi Onyema Oshim ◽  
Bright Unaeze ◽  
Okeke Monique Ugochukwu
Keyword(s):  
Primary Schools ◽  
Diagnostic Performance ◽  
Strongyloides Stercoralis ◽  
Soil Samples ◽  
Health Concern ◽  
Recovery Rates ◽  
Concentration Technique ◽  
Wet Mount ◽  
Stool Samples ◽  
Positive Results

Background: Geohelminths are groups of four intestinal soil transmitted parasites.They are of public health concern due to their serious morbidity they cause in children which are the major groups affected. Aim/Objective: The aim of this study is to evaluate the diagnostic performance of wet mount and concentration techniques of stool and soil samples for identification of geohelminths. Methodology: Eighty stool samples were collected from four primary schools, while forty soil samples were collected from the important sites (playground, and classroom areas) in each of the school accessed. The stool samples were examined with the wet preparation and formol-ether concentration technique, while the soil samples were examined with the formol-ether concentration technique. Ethical approval was sought from the Faculty of Health Sciences and Technology. Results: The results of geohelminths showed an overall prevalence of 6.25% (5/80) from the stool samples, and 27.5% (11/40) obtained from the soil. Recovery rates from the stool showed the presence of only two geohelminth;Hookworm (5%) and Strongyloides stercoralis (1.25%). Out of the four schools examined only three showed positive results with geohelminth infections, while the remaining school showed positive results with only Giardia.lamblia. The recovery rates from the soil also showed the same pattern of distribution as with the stool but with a higher prevalence of Hookworm (20.7%) and Strongyloides stercoralis (7.5%) with the toilet areas showing the highest prevalence (50%). The dominant specie of geohelminth observed in both stool and soil was Hookworm. The results also showed that both male (6%) and female (6.7%) are susceptible to the infection with no significant difference between their prevalances (p>0.05). Conclusion: The prevalence of Hook worm was poorly reported by wet mount technique.The diagnostic performance of concentration methods for the diagnosis of Hook worms in the samples was notably high as compared to wet mount techniques.

Covid-19: A review of its clinical features, effects on gastrointestinal system and possibility of faecal transmission

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 623-627
Author(s):  
Kanishk K Adhit ◽  
Anjankar Ashish P ◽  
Siddhaarth K
Keyword(s):  
Clinical Presentation ◽  
Throat Swab ◽  
Respiratory Illness ◽  
Review Article ◽  
Gastrointestinal System ◽  
Rt Pcr ◽  
Significant Evidence ◽  
Stool Samples ◽  
High Possibility ◽  
Positive Results

In China, Wuhan in the province of China, COVID-19 a patient suffering from pneumonia was tested and to identify the cause, the throat swab of the patient was tested. On 7th January 2020 WHO declared the identification as COVID-19. And then it was proclaimed as a pandemic. It classically causes a respiratory illness presenting as a mild cough, fever and . However, several investigators have advocated the involvement of the gastrointestinal tract and liver in COVID-19 infection similar to other infections. Further research studies have shown results that are expanding the possibility of transmission because RT-PCR assessment has shown significant evidence for the presence of virus not only in samples but also in stool samples. Studies have shown that virus in stool samples have got positive results even after the illness has resolved, and two respiratory tests were done 24 hours after COVID-19 being tested negative. The review article the different findings of the clinical presentation of COVID-19. It sheds light on the effects of COVID-19 in the gastrointestinal system along with the reasons for the high possibility of transmission of COVID-19 through the route.

scholarly journals Parasitic infections in Swiss children: Are we overtesting?

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Corinne Légeret ◽  
Céline Rüttimann ◽  
Hans Fankhauser ◽  
Henrik Köhler
Keyword(s):  
Retrospective Study ◽  
Positive Result ◽  
Pediatric Patients ◽  
Intestinal Parasites ◽  
Gastrointestinal Symptoms ◽  
International Travel ◽  
Parasitic Infections ◽  
Stool Samples ◽  
Stool Specimens

Abstract Background A wide variation of causes can lead to gastrointestinal symptoms in children- an infection with parasites is one of them. The expansion of international travel might lead to an increase in testing children for a correspondent infection. Currently there are no guidelines available, which patients should be tested for a possible parasitical infection. The aim of the study was to characterize Swiss children suffering from intestinal parasites, in order to provide more knowledge for the clinician who should be tested. Methods This is a retrospective study of Swiss pediatric patients, whose stools have been tested for parasites and helminths. Results A total of 1855 stool samples, belonging to 572 different children with an average age of 7.9 years, were tested within a 10-year period. The prevalence of a positive result was 4.2%, of which all were positive for Blastocystis, and 12.5% had a co-infection with Endolimax nana. Conclusion Immigrants, immune compromised children with diarrhea and pediatric patients with bloody or protracted diarrhea should have 2 different stool specimens examined for a possible parasitical infection.

scholarly journals Phenotypic Characterization and Molecular Identification of Intestinal Candida Spp. in Tunisia

2021 ◽  
Vol 14 (6) ◽  
Author(s):  
Khouloud Ben-Rhouma ◽  
Salma Feki Ben-Salah ◽  
Nada Boulehmi ◽  
Aida Bouratbine
Keyword(s):  
Oxidative Stress ◽  
Antifungal Susceptibility ◽  
Resistance Rate ◽  
Phenotypic Characterization ◽  
Its2 Region ◽  
Candida Spp ◽  
Health And Disease ◽  
Stool Samples ◽  
Stool Specimens

Background: Yeast naturally colonize the mammalian digestive tract and play an important role in health and disease. This community is composed of commensal yeasts, mostly Candida and Saccharomyces described as a part of the intestinal mycobiome and could be associated with resident or transient flora. Objectives: The aim of our study was to perform the phenotypic and genotypic characterization of culturable Candida isolates present in stool specimens of healthy Tunisian individuals and to evaluate their antifungal susceptibility. Methods: Yeasts were recovered from 46 stool samples cultured on Sabouraud dextrose agar at 37°C. Species were identified using conventional methods and ITS-PCR sequencing. Candida isolates were tested by exploring their tolerance to oxidative stress and extreme acidic conditions. In addition, their biofilm formation ability and in vitro resistance to antifungals was determined by the VITEK 2 system. Results: The identification by sequencing the ITS1-5.8S-ITS2 region of the 56 yeast strains isolated from 37 stool samples revealed that Candida was the dominant genus and was represented by Candida albicans (n = 21), C. parapsilosis (n = 10), C. glabrata (n = 9), and C. krusei (n = 9). In contrast, the other genera, including trichosporon, geotrichum, and rhodotorula, were sporadically occurring. We found that most Candida strains were able to form biofilms under oxidative stress and extreme pH conditions. Regarding antifungal susceptibility, a higher resistance rate to fluconazole was revealed in comparison to caspofungin and micafungin. However, nonresistance was revealed against voriconazole, amphotericin B, and 5-flucytosine. Conclusions: This is the first work-generated data on cultivable yeasts from stool specimens of healthy individuals in Tunisia. Further metagenomic studies with a larger sample size are needed to better characterize the intestinal mycobiota.

scholarly journals Investigation of Giardia intestinalis Genotypes among the Food Handlers of Qazvin, Iran

2019 ◽  
Author(s):  
Mojtaba SHAHNAZI ◽  
Farzaneh NAGHIZADEH ◽  
Elham HAJIALILO ◽  
Safar Ali ALIZADEH ◽  
Mehrzad SARAEI ◽  
...  
Keyword(s):  
Giardia Intestinalis ◽  
P Value ◽  
Giardia Cyst ◽  
Food Handlers ◽  
Dehydrogenase Gene ◽  
Stool Samples ◽  
Stool Specimens ◽  
The Impact ◽  
Concentration Methods

Background: We aimed to investigate the genotypes of Giardia intestinalis among the food handlers in Qazvin, Iran. Methods: Overall, 1530 stool specimens were collected from the food handlers who visited Shahid Bolandian Health Center, Qazvin, Iran during 2016. Specimens were evaluated by microscopic and concentration methods. Twenty specimens with appropriate number of giardia cysts were selected followed by DNA extraction. Determination of giardia genotypes was achieved through PCR and sequencing the glutamate dehydrogenase gene. The phylogenetic tree was drawn using the MEGA7 software. Finally, the data were analyzed statistically with a P-value<0.05 was considered as significant. Results: Twenty stool samples (1.3%) were positive for Giardia cyst. All positive specimens were obtained from male participants with abdominal cramp being their most common symptoms. The mean age for infected individuals was 32 yr. Molecular characterization was successfully performed for 17 isolates and two genotypes A (AII, 65%) and B (BIII, 35%) were identified. Conclusion: The most prevalent giardia genotypes among the food handlers in Qazvin were A (AII) and B (BIII) genotypes with A (AII) genotype as the dominant one in the region. Considering the direct association between the food handlers and public health as well as the impact of geographical and host conditions on dispersion and pathogenicity of various genotypes and their zoonotic aspects, further investigations are necessary.

scholarly journals Frequency of Rotavirus, Adenovirus and Astrovirus among Patients with Acute Diarrhea by Chromatographic Immunoassay and Enzyme

2016 ◽  
Vol 10 (2) ◽  
pp. 58-64
Author(s):  
Arwa Mujahid Abdullah Al-Shuwaikh
Keyword(s):  
Clinical Settings ◽  
City Hospital ◽  
Viral Pathogens ◽  
Inappropriate Use ◽  
Medical City ◽  
Elisa Technique ◽  
Stool Samples ◽  
Infant And Young Children ◽  
Stool Specimens ◽  
Age Range

Diarrhea is a major cause of illness and death in children worldwide; however, little information exists about the origin of childhood diarrhea in Iraq. Rotavirus, Adenovirus and Astrovirus are the major causes of sever gastroenteritis in infant and young children, pattern also observed in adult. Confirmation of viral infection by laboratory testing is necessary for reliable surveillance and can be useful in clinical settings to avoid inappropriate use of antimicrobial therapy. Methods: A total of 188 patients their age range from 1-19 (Mean=5.57 ± S.D. = 4.81) years old suffering from diarrhea were included in this study. Stool samples were collected and tested for Rotavirus, Adenovirus and Astrovirus antigens by using the rapid chromatographic test and for Rotavirus and Adenovirus Antigens, ELISA also was done. Rotavirus, Adenovirus and Astrovirus antigens were determined by rapid chromatographic immunoassay in 27 specimens (14.36%), 0 (0%) and 0 (0%) of 188 frozen stool specimens, respectively. Moreover, of these 188 specimens, Rotavirus was found in 35 specimens (18.62%) and Adenovirus in 6 specimens (3.19 %) by using ELISA technique. The present results revealed that Rotaviruses and Adenoviruses have an important role in diarrhea among children especially those less than 5 year’s old and viral pathogens should be investigated routinely in diarrhea stool specimens. This study was aimed to determine the frequency of Rotavirus, Adenovirus and Astrovirus in patients with acute gastroenteritis admitted to Al-Emamain Al-Kadhemain Medical City Hospital in Baghdad-Iraq.

scholarly journals Clostridium difficile colonization among patients with clinically significant diarrhea and no identifiable cause of diarrhea

2018 ◽  
Vol 39 (11) ◽  
pp. 1330-1333 ◽  
Author(s):  
Erik R. Dubberke ◽  
Kimberly A. Reske ◽  
Tiffany Hink ◽  
Jennie H. Kwon ◽  
Candice Cass ◽  
...  
Keyword(s):  
Clostridium Difficile ◽  
Patient Population ◽  
Tertiary Care ◽  
Clinical Microbiology Laboratory ◽  
Care Hospital ◽  
Toxigenic Culture ◽  
Stool Samples ◽  
Stool Specimens ◽  
Clinically Significant ◽  
Culture Negative

AbstractObjectiveTo determine the prevalence of Clostridium difficile colonization among patients who meet the 2017 IDSA/SHEA C. difficile infection (CDI) Clinical Guideline Update criteria for the preferred patient population for C. difficile testing.DesignRetrospective cohort.SettingTertiary-care hospital in St. Louis, Missouri.PatientsPatients whose diarrheal stool samples were submitted to the hospital’s clinical microbiology laboratory for C. difficile testing (toxin EIA) from August 2014 to September 2016.InterventionsElectronic and manual chart review were used to determine whether patients tested for C. difficile toxin had clinically significant diarrhea and/or any alternate cause for diarrhea. Toxigenic C. difficile culture was performed on all stool specimens from patients with clinically significant diarrhea and no known alternate cause for their diarrhea.ResultsA total of 8,931 patients with stool specimens submitted were evaluated: 570 stool specimens were EIA positive (+) and 8,361 stool specimens were EIA negative (−). Among the EIA+stool specimens, 107 (19% of total) were deemed eligible for culture. Among the EIA− stool specimens, 515 (6%) were eligible for culture. One EIA+stool specimen (1%) was toxigenic culture negative. Among the EIA− stool specimens that underwent culture, toxigenic C. difficile was isolated from 63 (12%).ConclusionsMost patients tested for C. difficile do not have clinically significant diarrhea and/or potential alternate causes for diarrhea. The prevalence of toxigenic C. difficile colonization among EIA− patients who met the IDSA/SHEA CDI guideline criteria for preferred patient population for C. difficile testing was 12%.

Multiplex Detection of Rotavirus A, B, C, Norovirus GI and GII, Adenovirus, Astrovirus and Sapovirus in a Single PCR System in Stool Samples From Children With Acute Diarrhea

2021 ◽  
Author(s):  
Wei Li ◽  
Wei-wei Li ◽  
Lin Li ◽  
Lin He ◽  
Wen-qing Xiang ◽  
...  
Keyword(s):  
Acute Diarrhea ◽  
Simultaneous Detection ◽  
Melting Curve ◽  
Cross Reaction ◽  
Melting Curve Analysis ◽  
Clinical Test ◽  
Rotavirus A ◽  
Diarrhea Virus ◽  
Intestinal Pathogens ◽  
Stool Samples

Abstract We developed a RT-PCR combined with melting curve analysis (RRCMC) method for simultaneous detection of rotavirus A, B, C, norovirus GI and GII, adenovirus, astrovirus and sapovirus. Stool samples were collected from 160 children with acute diarrhea and tested by RRCMC assay. A total of 71 patients were tested positive with norovirus, adenovirus or rotavirus. The RRCMC assay has high specificity. There is no internal cross-reaction through the 8 diarrhea viruses and no cross-reaction of other commonly intestinal pathogens and human genome. The detection limit was ranging from 1×102 to 1×105 copies/ml for each diarrhea virus. In conclusion, the RRCMC method is a suitable rapid clinical test for infectious viruses, with the advantages of high-throughput, low cost, high sensitivity and specificity.

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