Wet Mount Microscopic Examination Research Articles

Prevalence and subtyping of Blastocystis sp. in ruminants in Southwestern, Iran

Blastocystis is the most common gastrointestinal protozoan parasite of humans and many vertebrates. This study was carried out to investigate the prevalence and determination subtype (ST) of Blastocystis in domestic ruminants of Shahrekord County, southwestern Iran. In this descriptive cross-sectional study, 330 ruminant fecal samples (107 cows, 115 sheep, and 108 goats) were evaluated by parasitological methods (direct wet mount microscopic examination and formalin-ether concentration), Giemsa staining, In vitro xenic culture (The modified Dobell and Laidlaw culture method), polymerase chain reaction, and sequencing from 2018 to 2019, then data were analyzed using SPSS software version 21. The overall Blastocystis positive in ruminants was 14.2% and the frequency of Blastocystis sp. in cattle, sheep, and goats were 0.93%, 17.4%, and 24.1% respectively. Molecular diagnosis techniques revealed that ruminants were infected with four STs (genotypes) of Blastocystis including ST5(21.3%), ST7(2.1%), ST10(17.1%) and ST14(57.4%). Also, the STs identified in cows were ST10, and the observed STs in sheep were ST5 (40%), ST7 (3%), ST10 (5%), ST14 (45%), and one unknown subspecies. Goats were infected by ST5 (7.7%), ST10 (23.1%), and ST14 (69.2%). In this study, ST14 was identified as the most common subtype of Blastocystis sp. that was not common between humans and livestock, meanwhile, ST5 and ST7 are common between humans and animals accounted 21.3% and 2.1% of the positive cases, respectively, and reinforces the hypothesis that ruminants are reservoirs of blastocystosis in humans.

The COVID-19 Severity and Its Association with Intestinal Parasite Coinfection and Urine Biochemical Parameters among COVID-19-Confirmed Patients Admitted to Debre Markos University COVID-19 Center, Northwest Ethiopia.

Though most people with COVID-19 disease show asymptomatic to mild illness, a substantial number of patients are at high risk of developing severe disease and adverse outcomes with long COVID-19 and death. Even though some studies showed that previously existing infections with parasites amend the host's body defenses to increase resistance to infection with SARS-CoV-2, there is limited data in Ethiopia. This study is aimed at determining the COVID-19 disease severity and its association with intestinal parasite coinfection and urine biochemical parameters among COVID-19-confirmed patients admitted at Debre Markos University COVID-19 Center, 2021. A prospective cohort study was conducted on 136 RT-qPCR-confirmed COVID-19 patients admitted at Debre Markos University COVID-19 Center from January 1 to March 30, 2021. Sociodemographic and clinical data were collected by using standardized data collection forms. A urine biochemical test was performed using a dry urine dipstick kit and stool examination using direct wet mount microscopic examination and formalin-ether concentration method. The chi-square test, Fisher exact test, and ordinal logistic regression analysis were computed to assess association with outcome variables using Statistical Package for Social Science software (version 24). A total of 136 COVID-19-confirmed patients participated in this study. The median age of the participants was 48 years. The majority (86 (62.5%)) of them were male in sex. Of the 136 cases, 39 (28.7%) had died. Among the 136 patients, 22 (16.2%) were coinfected with intestinal parasites. COVID-19 patients who have intestinal parasite coinfection had lower odds of developing clinically severe COVID-19 compared to noninfected (AOR = 0.37; 95% CI = 0.147-0.944; P = 0.037). The majority (104 (76.5%)) of them have abnormal urine biochemical results. From the abnormal urine biochemical tests observed, the urine blood, glucose, and ketone tests were positive for 54 (39.7%), 36 (26.5%), and 30 (21.1%) patients, respectively. Among the 31 critical COVID-19 patients, 25 (80.6%) showed abnormal urine biochemical parameters. Age and comorbidity were significantly associated with COVID-19 severity (P < 0.05). Patients with old age and comorbidity had an increased risk of developing severe COVID-19 disease. Patients having SARS-CoV-2 and intestinal parasitic coinfections demonstrated mild COVID-19 disease severity. Abnormal urine biochemical results were common among critical COVID-19 patients. Thus, advanced study on the effect of the interaction among intestinal parasites on COVID-19 clinical severity and its mechanisms is essential.

Detection of Fasciola Hepatica in Lori Sheep Using Polymerase Chain Reaction and Conventional Diagnostic Methods in Western Iran.

Fascioliasis is an emerging and important food and water-borne disease in human communities which has become one of the most important health challenges in countries, like Iran. It causes weight loss, a decrease in feed conversion ratio as well as milk and meat production, and also reduces fertility in animals the prevalence of fasciolosis is increasing in some regions of the world due to various factors. Different methods have been used for the detection of Fasciola hepatica in animals. This study is the first to detect F. hepatica in Lori sheep using polymerase chain reaction (PCR) and conventional diagnostic methods in Western Iran. During three months, 195 fecal samples were collected from sheep in Lorestan province, Iran, using the stratified random sampling method. The conventional diagnostic methods, including wet mount microscopic examination and concentration assays, as well as the PCR technique targeting the intergenic spacer gene of F. hepatica, were used for the detection of the parasite in sheep. In total, 4 (2.1%) out of 195 examined stool samples were positive for F. hepatica based on the conventional assays. The PCR test was positive for F. hepatica in7 (3.6%) samples of 195 studied specimens. Statistical analyses of the data revealed that there is a significant difference between the results of diagnostic methods for F. hepatica detection (P=0.0421). Finally, the results showed that PCR has more diagnostic sensitivity, compared to conventional diagnostic methods, including the concentration techniques and microscopic examination. Hence, it can be advised to use PCR for the detection of F. hepatica in sheep.

Molecular detection of glutamate dehydrogenase gene of Giardia lamblia isolated from food handlers in Erbil city

Background and objective: Giardia lamblia is the intestinal flagellated protozoan parasite that infects vertebrates, including humans. Giardiasis is the major diarrheal disease found worldwide. It can be symptomatic or may be an asymptomatic carrier that led to chronic disease. This study aimed to determine the proportion of giardiasis among food handlers and evaluate the correlation between two laboratory methods for identifying the Giardia lamblia. Methods: A total of 308 stool samples were collected from food handlers that annually attend the central laboratory in Erbil City. Wetmount microscopic examination was performed for the diagnosis of cysts and trophozoites of the Giardia parasite. Molecular analysis done for positive samples, DNA extraction performed using the QIAamp Fast DNA Stool Mini Kit (Qiagen Company, Germany). Nested PCR analysis was done targeting the Glutamate dehydrogenase gene using two sets of primers for amplification of 734bp fragment. Gel electrophoresis was performed for visualizing the amplified DNA by Ultraviolet light. Results: The mean age of food handler participants was 29 years. Most (93.8%) of the food handlers were males, and the majority (98.6%) of the participants did not have any signs and symptoms. Four (7.4%) microscopy positive sample participants were highly educated. There was no association between educational level and positive rate by microscopy (P = 0.066). The majority of participants did not receive treatments, particularly most of the microscopic positive samples. The food handlers did not take any antiparasitic treatments 9 (3.4%) (P = 0.676). From 11 (3.6%) microscopically positive samples, 10 (90.9%) Giardia lamblia gdh gene 734 bp fragments were amplified by nested PCR. Conclusion: Amplification of 734bp of gdh gene by the nested PCR is the most specific and sensitive method for identifying Giardia lamblia. Food handlers were important people to care about sanitation and preparing food, particularly for avoiding diseases transmitted by food. Keywords: Giardiasis; Genetic characterization; gdh gene; Nested PCR.

Intestinal parasitic infection: prevalence, knowledge, attitude, and practices among schoolchildren in an urban area of Taiz city, Yemen.

BackgroundIntestinal parasitic infections (IPIs) are regarded as one of the main public health problems and socio-economic issues adversely affecting the health of millions of people worldwide. Our study aimed to describe the knowledge, attitude, and practices of local urban schoolchildren in Taiz City towards intestinal parasitic infections.Methods and materialThis is a cross-sectional study conducted in Taiz, Yemen from March to May 2019. A total of 385 schoolchildren were selected using a random sampling technique from 7 primary schools. Wet-mount microscopic examination, formol-ether concentration techniques, and Lugols' iodine were employed in parasite detection and cyst identification.ResultsOf the 385 schoolchildren examined for IPIs, 107 (27.8%) were positive for the presence of enteric parasites, some having multiple infections. The prevalence was slightly higher in males 46 (28.6%) than in females 61 (27.2%) but have no statistical difference (P = 0.77). Entamoeba histolytica/dispar was the most common infection with 16.4% of cases. A substantial percentage (40.5%) of the respondents displayed poor knowledge. The respondents also revealed inappropriate attitudes and practices that contribute to the prevalence of IPIs in the study.ConclusionsThe study revealed the prevalence of intestinal parasites among the schoolchildren in Taiz, Yemen, suggesting that IPIs remain a major public health problem. Entamoeba histolytica/dispar was the most prevalent intestinal parasites identified among the schoolchildren. Age, poor knowledge of the mode of transmission, prevention, and acquisition of IPIs, and poor habitual hygiene practices increase the risk of acquiring intestinal infections.

Prevalence of bovine fascioliasis in a new-emerging focus of human fascioliasis in BoyerAhmad district, southwest of Iran

BackgroundThe prevalence of fascioliasis in a population of cattle in a new-emerging focus of human fascioliasis in Boyer-Ahmad District, in the southwest of Iran, was investigated, using an ELISA system and coprological methods. MethodsBlood, as well as stool samples, were collected from 150 dairy cattle consisted of 82 (54.7%) males and 68 (45.3%) females, aged from 1 to 8 years, selected from different pastures. The stool samples were evaluated by direct wet mount microscopic examination as well as sedimentation methods. Moreover, modified Telemann was used for detecting of Fasciola eggs. Anti-Fasciola antibodies in the cattle sera samples were determined, using a Fasciola excretory-secretory antigen-specific ELISA. ResultsAnti-Fasciola antibodies were detected in 64 (42.4%) of the subjects by ELISA. Out of 64 seropositive cases, 29 (45.3%) were female and 35 (54.6%) were male. No significant association was found between sex and seropositivity to fascioliasis. Considering the age of the cattle, the highest prevalence of fascioliasis (23%) was found in the 5-year old age group. However, the difference between the age of the cattle and seropositivity to fascioliasis was not statistically significant (P > 0.05). Fasciola eggs were not detected in fecal samples of any of the studied cattle, while Paramphistomide, as well as Dicrocoelium dendriticum eggs, were detected in 6 (4%) and 17 (11.3%) of the subjects, respectively. ConclusionFindings of the current study provide basic information about bovine fascioliasis in a new focus of human fascioliasis in Iran, which is needed for effective control of this parasitic infection in such areas.

Accuracy of the BD MAX™ vaginal panel in the diagnosis of infectious vaginitis

The aim of this study was to evaluate the BD MAX™ vaginal panel in the diagnosis of bacterial vaginosis (BV), vulvovaginal candidiasis (VVC), and trichomoniasis by comparing it with conventional methods: (i) combination of Hay criteria and presence of clue cells with predominant growth of Gardnerella vaginalis, (ii) yeast culture, and (iii) combination of culture, wet mount microscopic examination, and an alternative molecular assay. One thousand vaginal samples of women ≥ 14years were analyzed; 5% of the samples belonged to pregnant women. 19.3% were classified as BV, in 33.6% yeasts were recovered and in 1.5% TV was detected. For BV, sensitivity and specificity were of 89.8% and 96.5%, respectively; for VVC, sensitivity and specificity were of 97.4% and 96.8%, respectively, and for T. vaginalis, the sensitivity and specificity were of 100%. The BD MAX™ vaginal panel is highly sensitive and specific and simplifies the identification of infectious vaginitis.

Prevalence of intestinal parasite infections among patients in local public hospitals of Hail, Northwestern Saudi Arabia

To evaluate the prevalence of intestinal parasites among patients in Hail, Northwestern Saudi Arabia. Stool samples were collected from 130 patients (69 females and 61 males) in Hail General Hospital. Each sample was examined by direct wet mount microscopic examination using both normal saline and Lugol's iodine preparation and concentration techniques using salt and formol-ether solutions. Permanent stained smears were performed for intestinal coccidian using modified Ziehl-Neelsen technique. The overall prevalence of intestinal parasitic infection was 45.38% (59 cases). Forty-four (33.84%) were found to be infected with one or more intestinal protozoa, 5 (3.84%) were infected with helminthes and 10 (7.69%) had mixed infection with both helminthes and protozoa. The most common intestinal helminth detected was Ancylostoma duodenale (n=5, 3.84%), followed by Ascaris lumbricoides, Taenia sp. and Trichuris trichiura (n=2 for each species, 1.5%). For intestinal protozoa, the coccidian Cryptosporidium parvum (n=25, 19.23%) was the most common followed by Entamoeba histolytica/dispar (n=21, 16.15%), Giardia lamblia (n=15, 11.54%), Entamoeba coli (n=5, 3.85%) and Blastocystis hominis (n=3, 2.30%). The prevalence of intestinal parasitic infections in females was significantly higher than in males (P<0.05). This is the first study highlighting that intestinal parasites are still an important public health problem in Northwestern Saudi Arabia. Therefore, health education would be the best way to prevent from intestinal parasite infections which are mainly food borne diseases.

Detection of Trichomonas vaginalis in male patients with urethritis by nested PCR

Objective To establish two nested PCR assays for detection of Trichomonas vaginalis in urine samples from male patients with urethritis,and to evaluate their diagnostic value.Methods One thousand and eighty-eight male patients with urethritis were enrolled from sexually transmitted disease (STD) clinic in the Hospital of Dermatology,Chinese Academy of Medical Sciences and Peking Union Medical College between April 2011 and December 2013.Urethral swabs were collected followed by smear testing,wet mount microscopic examination of Trichomonas vaginalis,and cultivation of Neisseria gonorrhoeae.Urine specimens were also obtained from these patients followed by DNA extraction.Two nested PCR assays were developed and performed to amplify the repeat genomic sequence and β-tubulin gene of Trichomonas vaginalis.Results Trichomonas vaginalis was detected in none of these swab specimens by wet mount microscopy,but in 29 (2.67％) of the urine specimens by either of the two nested PCR assays.Moreover,the positive specimens detected by the two nested PCR assays were completely consistent.Conclusion Compared with wet mount microscopy,nested PCR has higher sensitivity and specificity in detection of Trichomonas vaginalis in urine samples from male patients. Key words: Urethritis; Trichomonas vaginalis; Polymerase chain reaction

Comparison of clinical and gram stain diagnosis methods of bacterial vaginosis among pregnant women in ethiopia.

Bacterial Vaginosis (BV) is characterized by an increased thin homogenous white vaginal discharge accompanied by fishy odour and increased vaginal pH. It is associated with different gynecologic and poor obstetric outcome. Bacterial vaginosis can be easily diagnosed by combination of two Amsel's criteria. The aim of this study was to evaluate the accuracy of Amsel's criteria individually or in combination of two for the clinical diagnosis of bacterial vaginosis among pregnant women in Ethiopia. In this crosssectional study 252 pregnant women were screened for bacterial vaginosis. Vaginal swabs were collected for pH determination, saline wet mount microscopic examination to detect clue cells, KOH preparation for whiff test and Gram-stain evaluation of vaginal flora for diagnosis of bacterial vaginosis by Nugent scoring system. Accuracy of clinical diagnosis using individual and two of Amsel's criteria was evaluated. The prevalence of BV was 18.3% by Amsel's two of three criteria and 19.4% Gram by Nugent's methods. Comparing with Nugent scoring methods, the clinical diagnosis by Amsel's criteria had sensitivity of 85.7%, specificity of 98%. The most sensitive and specific individual Amsel's criterion was clue cells. Amsel's criteria with the lowest sensitivity and specificity were whiff test and vaginal pH respectively. Combination of clue cells with vaginal pH test were the highest in sensitive while whiff test with clue cells were the highest in specificity than the other combined two Amsel's criteria. Amsel's criteria diagnosis of bacterial vaginosis can be simplified by using a combination of the two criteria, vaginal pH and clue cells, in settings where time or Gram staining is not available.

English

IntroductionMaharashtra is a very large state of 300,000 km2, with a total population of around 97 million. The capital city of Maharashtra, Mumbai, is the most populous city in India, with around 14 million inhabitants. The HIV prevalence at antenatal clinics in Maharashtra was 0.5% in 2007. The state has the highest reported rates of HIV prevalence among female sex workers (18%). Similarly high rates were found among injecting drug users (24%) and homosexual men (12%). Pune is the second largest city in Maharashtra, with a growing population of more than 40 lakhs (4 million). It ranks among the top five HIV prevalent cities in the state. There are very few studies that have been carried out to compare the prevalence of intestinal parasitic infestation in HIV-reactive and non-reactive individuals in Maharashtra. Materials and MethodsStudy PeriodThe present study was carried out from 1st December 2008 to 31st August 2010 in Pad. Dr. D.Y. Patil Medical College Hospital and Research Center, Pimpri, Pune. Results and ObservationsIn this study, stool samples of 490 individuals were processed, out of which 110 were HIV-positive and 380 were HIV-negative. Evaluation of 4 different stool concentration techniques was done in comparison with the direct wet mount microscopic examination. Out of all the stool samples examined, 100 of them were also processed using concentration techniques (by all methods). It was seen that using routine examination, only 6% of the stool samples revealed a positive finding, whereas using concentration techniques a maximum of 17% of the same samples were positive. ConclusionFurther, as demonstrated in our study, we can conclude that stool concentration techniques should be adopted, since in case of low parasite load, often the diagnosis is missed by carrying out only direct wet mount examination. Finally, to prevent intestinal parasitic infections, patients should be educated regarding maintenance of personal hygiene. Keywordsintestinal parasites, Ascaris lumbricoides, H. nana, T. solium, T. saginata

Comparison of white and red blood cell estimates in urine sediment with hemocytometer and automated counts in dogs and cats

Therapeutic decisions regarding urinalysis are commonly based on the presence of white and red blood cells. Traditionally, numbers per high-power field are estimated using wet-mount microscopic examination. This technique is not standardized and counts are likely prone to inaccuracy. In addition, differentiation of leukocyte types is not possible. The aims of this study were to (1) compare WBC and RBC estimates using wet-mount examination with counts obtained using a hemocytometer, (2) assess if a hematology automated analyzer (Sysmex ST-2000iV/XT) provides reliable WBC and RBC counts in urine comparable to hemocytometer counts, and (3) evaluate air-dried Wright-Giemsa-stained urine drop sediment preparations for the determination of differential leukocyte counts. WBC and RBC counts were obtained by performing wet-mount estimates, manual hemocytometer counts, and Sysmex automated counts on 219 canine and feline urine samples. Results were correlated using Spearman rank correlation. Air-dried Wright-Giemsa stained sediment drop preparations (n = 215) were examined for differential counts of leukocytes. A low but significant association was found between WBC estimates on wet-mount examination and hemocytometer counts (rho = 0.37, P < .01). There was a high and significant association when RBC counts were compared between wet-mount and hemocytometer evaluation (rho = 0.7, P < .01). There was very high and significant interassay correlation between Sysmex data from duplicate samples for what the analyzer classified as WBC (rho = 0.97, P < .01) and RBC (rho = 0.94, P < .01). Low correlations were found between the Sysmex RBC counts and both wet-mount estimates and hemocytometer RBC counts (rho = 0.43, P < .01 and rho = 0.39, P < .01, respectively). Cell preservation in the air-dried sediment preparations was so poor that differential counts could not be performed. WBC and RBC estimates on wet-mount examination agreed with hemocytometer counts and are therefore considered adequate. The Sysmex ST-2000iV/XT did not provide reliable cell counts under the conditions used.

Real-time PCR improve detection of Trichomonas vaginalis compared to conventional techniques

Trichomonas vaginalis is the cause of one of the most common types of vaginitis, trichomoniasis. Clinical manifestations of symptomatic women are generally nonspecific, but include vaginal discharge, vaginitis and irritation. T. vaginalis infection has also been linked to the increased risk of human immunodeficiency virus transmission. The aim of the study was to compare a real-time polymerase chain reaction (PCR) assay with culture and wet-mount examination for the detection of T. vaginalis. This is a descriptive analytical study. Vaginal swabs from 504 female patients with suspected vaginitis were included in the study. They were subjected to culture, wet-mount microscopic examination (WM), and real-time PCR. Real-time fluorescence resonance energy transfer hybridization probe PCR assays were used in this study to test for T. vaginalis DNA, targeting the b-tubulin genes. The result of the PCR was compared with culture and wet-mount microscopy. WM were positive for T. vaginalis in 60/504 cases (11.9%) and cultures were positive for T. vaginalis in 116/504 cases (23%). Real-time PCR was done on 50/504 specimens which was randomly chosen, 33/50 (66%) cases were positive for T. vaginalis (78% sensitivity), 25/50 (50%) of them were culture and wet-mount examination positive. Of them, 1/33 (3%) were culture positive and wet examination negative, 7/33 (21%) real-time positive were negative by culture while 17/50 (34%) real-time PCR negative cases were also negative by both techniques. The time taken for PCR assay was 4 to 8 h whereas positive protozoal cultures took up to 4 days. The Real-time PCR done in this study, provide a rapid, sensitive and specific diagnosis of T. vaginalis infection.

P3-S7.08 Clinical evaluation of the APTIMA® Trichomonas vaginalis assay on the TIGRIS® DTS® system in asymptomatic and symptomatic female subjects

BackgroundThis study evaluated the clinical performance of the APTIMA® Trichomonas vaginalis (ATV, Gen-Probe Incorporated) Assay, a nucleic acid amplification test for the diagnosis of Trichomonas vaginalis (TV) infection, in asymptomatic...

Correlation of Trichomonas vaginalis to bacterial vaginosis: a laboratory-based study

This study aimed to define the occurrence of different organisms causing vulvovaginitis; to evaluate different laboratory methods used for diagnosis of Trichomonas vaginalis (T. vaginalis); and to evaluate the direct score system and clue cell method compared with culture for diagnosis of bacterial and T. vaginalis vaginosis. Clinical and laboratory evaluations were performed for 110 patients. Laboratory methods used for bacteriological diagnosis were direct Gram staining for clue cells and scoring by Nugent score system and bacterial culture. T. vaginalis was identified by wet mount microscopic examination, culture, direct Gram, Giemsa staining and acridine orange (AO). The Nugent score method revealed that the sensitivity and specificity for diagnosis of vaginal discharge by direct rapid microscopic methods were 30% and 80% and for clue cells sensitivity and specificity were 37% and 75% respectively for diagnosis of bacterial vaginosis compared to culture. For diagnosis of T. vaginalis, the Nugent score method revealed that the sensitivity and specificity were 60% and 90% respectively, and for clue cells 75% and 80% respectively. For microcopic methods used for T. vaginalis only, the Gram stain and Giemsa stain sensitivities were poor (15.2% and 48.5%, respectively). Wet mount showed reasonable sensitivity of 75.8%. Acridine orange sensitivity was 93.9% and specificity was 97.5%, Prevalent pathogens associated with vaginitis were (Gardnerella vaginalis) G. vaginalis, T. vaginalis and Mycoplasma hominis (M. hominis). Wet mount microscopic examination, acridine orange, and high Nugent score were found as rapid and sensitive methods for diagnosis of T. vaginalis.

Evaluation of direct wet mount parasitological examination of preserved fecal specimens

A retrospective study covering a 12-year period was performed to determine the contribution of the direct wet mount microscopic examination to the identification of intestinal parasites in preserved fecal material. It was determined that each of 898 specimens contained at least one parasite when processed by the direct wet mount, concentration, and trichrome staining procedures. Of these procedures, the direct wet mount examination was solely responsible for the identification of 45 (2.9%) of 1,581 parasites identified. This is in contrast to the 15.1 and 12.5% which were found exclusively by the concentration and trichrome methods, respectively. These percentages may vary, depending on the prevalence of parasites and the stages present in the stool specimen.

Direct wet mounts versus concentration for routine parasitological examination: are both necessary?

The authors evaluated the usefulness of direct wet mount microscopic examination of stool samples for routine parasitologic diagnosis compared with formalin-ethyl acetate concentration detection. Over a three-year period, there were no instances in which an intestinal parasite was detected only by the direct wet mount examination. Elimination of routine direct wet mount examinations can reduce laboratory cost and save significant technologist time without decreasing the sensitivity of microscopic examinations for common parasitic agents.