Evaluation of microscopy and PCR for detection of Dientamoeba fragilis.

Introduction: Dientamoeba fragilis (D. fragilis) diagnosis is an intestinal protozoan parasite globally found in rural and urban areas and is attracting a growing interest. Its prevalence in stool varies from 0.2% to more than 19% depending upon the population studied. Materials and Methods: This study was based on the examination of 100 stool samples of randomly referred cases in a rural area in Motobus district, Kafr El-Sheikh governorate, Egypt. Our aim was to investigate the presence of D. fragilis in stool of the examined individuals using conventional polymerase chain reaction (PCR) compared to wet mount and trichrome stain with confirmation of infection by transmission electron microscopy. Results: D. fragilis was detected in 13/100 of the stool samples examined using wet mount smears, while trichrome stain detected 17/100. Conventional PCR diagnosed 41 cases of D. fragilis in the studied group. A very good agreement was found between wet mount and trichrome stain for diagnosing D. fragilis, while there was fair agreement between conventional PCR and both microscopy methods. Transmission electron microscope was performed on pooled positive samples that revealed the internal structures of D. fragilis trophozoite with its characteristic nucleus. Conclusions: PCR technique was superior to microscopy for the detection of D. fragilis. Trichrome stain remains vital for microscopic diagnosis.

A Fully Remote Diagnostic and Treatment Pathway in Patients with Obstructive Sleep Apnoea during the COVID-19 Pandemic: A Single Centre Experience.

The COVID-19 pandemic led to significant delays in the diagnostic and management pathway of patients with obstructive sleep apnoea (OSA). During the first wave of COVID-19, our department adopted a fully remote diagnostic (home cardiorespiratory polygraphy) and treatment (autoset continuous positive airway pressure, CPAP) approach. As a novel mode of service delivery, our aim was to evaluate our pathway and analyse factors associated with adherence to CPAP. We analysed the first 300 patients (51 ± 13 years, 48% men) who were set up on remote CPAP between 20 May 2020 and 11 September 2020. The associations between CPAP usage at 90 days and age, gender, body mass index, disease severity, Epworth Sleepiness Scale and comorbidities were investigated with linear and logistic regression analyses. A total of 124 patients (41.3%) were fully-adherent to CPAP therapy, defined as CPAP usage ≥ 4 h on ≥ 70% of the days. Only driving status was associated with adherence to CPAP. Patients who were adherent at 28 days were more likely to stay adherent at 90 days (3.77 odd ratio /3.10-4.45/ 95% confidence interval). We have shown that a fully remote diagnostic and treatment pathway for patients with OSA can be successfully delivered, and our preliminary outcomes of adherence to CPAP are comparable with published data.

Performance of formalin ethyl acetate, percoll sedimentation and ELISA for the detection of Cryptosporidium infection in asymptomatic children.

This study aimed to assess the performance of formalin ethyl acetate (FEA)/modified Ziehl-Neelsen (MZN), and percoll technique/MZN for the diagnosis of cryptosporidiosis among asymptomatic children compared to ELISA coproantigen. The study was conducted on 100 children in a rural area in Kafr El-Sheikh governorate. Stool samples were collected and examined by the three techniques. Microscopic examination revealed the presence of acid-fast stained oocysts and non-acid fast ghost oocysts. The overall prevalence rate was 7% with an infection intensity of 1-5 oocysts/oil immersion field. FEA/MZN technique showed the highest diagnostic performance (5%) with 71.4% sensitivity and 98% negative predictive value (NPV) compared to the other techniques. ELISA revealed 3% prevalence, 42.9% sensitivity and 96% NPV. Percoll/MZN gave the lowest prevalence, sensitivity and NPV (1%, 14.29% and 93.9% respectively). Agreement fluctuated between moderate and poor regarding FEA/MZN versus ELISA and percoll/MZN versus both techniques. In conclusion, FEA/MZN gave the top diagnostic performance, yet it missed some positive cases. Its combination with ELISA coproantigen might prove beneficial for Cryptosporidium diagnosis. Percoll technique needs more validation by modifying the density gradient, speed of centrifugation, and staining methods.

Intestinal Microsporidia Infection in Leukemic Children: Microscopic and Molecular Detection.

BACKGROUND: Microsporidia infection was originally described as an immunocompromised associated pathogen. Limitations to correct microscopic diagnosis of microsporidia include size of the organism presenting a challenge even to a highly competent laboratory expert. OBJECTIVE: The present study aimed to detect microsporidia infection among leukemic children. The performance of modified trichrome stain and PCR in the diagnosis of microsporidia was evaluated with further speciation. METHODS: Stool samples of 100 leukemic children on chemotherapy were examined microscopically for microsporidia. DNA was extracted from all samples. Amplification was performed by conventional and nested PCR. Sequencing of amplified products was performed on unspeciated samples. RESULTS: Microsporidia were detected in 23% of the children by MTS and 29% by PCR. The 29 positive samples were subjected to PCR for speciation. Enterocytozoon bieneusi was found to predominate in 20 cases, Encephalitozoon intestinalis in three cases, two cases had co-infection, and the remaining four samples were not amplified with either E. bieneusi or E. intestinalis specific primers. By DNA sequencing of the unspeciated samples, three samples shared high homology with Encephalitozoon hellem and one sample with Encephalitozoon cuniculi. Referring to PCR as a gold standard, MTS exhibited 72.4% sensitivity and 97.2% specificity with 90% accuracy. Among a number of studied variables, diarrhea and colic were significantly associated with microsporidia infection when diagnosed by either technique. CONCLUSION: The use of sensitive and discriminative molecular tools will contribute to determining the true prevalence of microsporidiosis and possibly their potential transmission source depending on species identification.

Uncomplicated falciparum malaria among schoolchildren in Bajil district of Hodeidah governorate, west of Yemen: association with anaemia and underweight.

BACKGROUND: Malaria, malnutrition and anaemia are major public health problems in Yemen, with Hodeidah being the most malaria-afflicted governorate. To address the lack of relevant studies, this study was conducted to determine the prevalence of Plasmodium falciparum and its relation to nutritional status and haematological indices among schoolchildren in Bajil district of Hodeidah governorate, west of Yemen. METHODS: A cross-sectional study was conducted among 400 schoolchildren selected randomly from four schools in Bajil district. Data about demographic characteristics, risk factors and anthropometric measurements of age, height and weight were collected. Duplicate thick and thin blood films were prepared, stained with Giemsa and examined microscopically for malaria parasites. The density of P. falciparum asexual stages was estimated on thick films. EDTA-blood samples were examined for the haematological indices of haemoglobin (Hb) and blood cell counts. RESULTS: Plasmodium falciparum was prevalent among 8.0% (32/400) of schoolchildren with a mean parasite density of 244.3 ± 299.3/µL of blood and most infections showing low-level parasitaemia, whereas Plasmodium vivax was detected in one child (0.25%). Residing near water collections was a significant independent predictor of falciparum malaria [adjusted odds ratio (AOR) = 2.6, 95.0% CI 1.20-5.72; p = 0.016] in schoolchildren. Mild anaemia was prevalent among more than half of P. falciparum-infected schoolchildren and significantly associated with falciparum malaria (AOR = 5.8, 95.0% CI 2.39-14.17; p < 0.001), with a mean Hb concentration of 10.7 ± 1.0 g/dL. Although the mean values of the total white blood cells, monocytes and platelets were significantly lower in infected than non-infected schoolchildren, they were within normal ranges. More than half of the children were malnourished, with stunting (39.3%) and underweight (36.0%) being the most prevalent forms of malnutrition; 6.3% of children were wasted. Underweight (AOR = 5.3, 95.0% CI 2.09-13.62; p < 0.001) but not stunting or wasting, was a significant predictor of falciparum malaria among schoolchildren. CONCLUSION: Asymptomatic falciparum malaria is prevalent among schoolchildren in Bajil district of Hodeidah Governorate, with predominance of low parasitaemic infections and significant association with mild anaemia and underweight. Residence near water collection is a significant predictor of infection with falciparum malaria among schoolchildren. Further studies among children with severe malaria and those with high parasite densities are recommended.

Toxoplasma gondii seropositivity in renal patients: rate, pattern, predictors and related morbidity.

Infection is a significant cause of morbidity and mortality in patients with chronic kidney disease (CKD) due to their depressed immunity. T. gondii is a ubiquitous parasite that causes severe manifestations in immunocomprmised patients. The present study investigated rate, pattern, predictors and related morbidity of T. gondii seropositivity in CKD patients. The study included four groups: i- patients on maintenance hemodialysis (HD; n = 60); ii- patients with systemic lupus erythematosus on immunosuppressive therapy for lupus nephritis (SLE; n = 30) iii-Renal transplant recipients (RTR; n = 30) and iv- healthy controls (HC; n = 30). Anti-Toxoplasma IgG, IgM & IgG avidity were determined using enzyme immunoassays. Patients' medical data and information on plausible risk factors for toxoplasmosis were recorded. Results revealed that T. gondii seropositivity rates in HD, SLE and RTR groups (61.7, 60 & 70% respectively) were significantly high compared to HC (30 %). Among seropositive patients, 79% of those with negative IgM displayed high IgG avidity confirming past infection. None of IgM positive patients had low IgG avidity. The latter was detected in some IgM negative patients. Multivariate analysis showed that seropositivity was significantly associated with undercooked meat consumption (adjusted OR = 6.256, CI = 2.167-18.056) and blood transfusion (adjusted OR = 5.953, CI = 2.987-11.864). No significant association could be found between T. gondii seropositivity and the clinical manifestations of CKD patients.

Prediction of successful trial of labour in patients with a previous caesarean section.

OBJECTIVE: To determine the prediction rate of success in trial of labour after one previous caesarean section. METHODS: The cross-sectional study was conducted at the Department of Obstetrics and Gynaecology, Cantonment General Hospital, Rawalpindi, from January 1, 2012 to January 31, 2013, and comprised women with one previous Caesarean section and with single alive foetus at 37-41 weeks of gestation. Women with more than one Caesarean section, unknown site of uterine scar, bony pelvic deformity, placenta previa, intra-uterine growth restriction, deep transverse arrest in previous labour and non-reassuring foetal status at the time of admission were excluded. Intrapartum risk assessment included Bishop score at admission, rate of cervical dilatation and scar tenderness. SPSS 21 was used for statistical analysis. RESULTS: Out of a total of 95 women, the trial was successful in 68 (71.6%). Estimated foetal weight and number of prior vaginal deliveries had a high predictive value for successful trial of labour after Caesarean section. Estimated foetal weight had an odds ratio of 0.46 (p < 0.001), while number of prior vaginal deliveries had an odds ratio of 0.85 with (p = 0.010). Other factors found to be predictive of successful trial included Bishop score at the time of admission (p < 0.037) and rate of cervical dilatation in the first stage of labour (p < 0.021). CONCLUSION: History of prior vaginal deliveries, higher Bishop score at the time of admission, rapid rate of cervical dilatation and lower estimated foetal weight were predictive of a successful trial of labour after Caesarean section.

Genotype analysis of T. gondii strains associated with human infection in Egypt.

The distribution of Toxoplasma gondii genotypes varies from one geographic area to another. The present study aimed to determine T. gondii genotypes associated with human infection in Egypt. Individuals seropositive for anti-toxoplasma IgG and IgM (group I, n = 50) or for specific IgG only (group II, n = 50) were enrolled. Of the participants, 75 % were asymptomatic pregnant women. The others presented with lymphadenitis (n = 21), chorioretinitis (n = 3), and unexplained hepatomegaly (n = 1). Using nested PCR, T. gondii GRA6-coding fragment was amplified from DNA extracted from blood samples of participants. Amplification was successful in 12 samples with nonsignificant difference between both groups but with a significant association with the presence of toxoplasmosis-related manifestations. Restriction fragment length polymorphism analysis of these samples revealed the presence of type I in seven samples and atypical types in five samples. Both typical and atypical strains were detected in individuals of both groups with no bias towards specific clinical presentation.

The effect of TiO2 and SiO2 nanoparticles on flexural strength of poly (methyl methacrylate) acrylic resins.

PURPOSE: TiO(2) and SiO(2) nanoparticles are products of nanotechnology which have been incorporated to acrylic resins (AR) in order to induce antimicrobial properties. However, as additives they can affect the mechanical properties of the final product. The aim of this study was to survey the effects of TiO(2) and SiO(2) nanoparticles on flexural strength (Fs) of poly (methyl methacrylate) acrylic resins. METHODS: Acrylic specimens (Selecta Plus) in size of 5×10 (±0.2)×3.3 (±0.2)mm were prepared and divided into 7 groups: AR containing nanoTiO(2), SiO(2) and TiO(2) with SiO(2) in two concentration of 1% and 0.5%, in addition to a control group. To prepare nano AR, nanoparticles were added to the monomer. All specimens were stored in 37°C distilled water and underwent Fs test by universal testing machine (Zwick). RESULTS: The maximum mean flexural strength (43.5 MPa) belongs to the control group and AR containing 0.5% of both TiO(2) and SiO(2) demonstrated the minimum mean Fs (30.1 MPa). Resins contained TiO(2), demonstrated lower values of Fs than those contained SiO(2) with the same concentration, but the differences were not significant (P>0.05). CONCLUSION: Incorporation of TiO(2) and SiO(2) nanoparticles into acrylic resins can adversely affect the flexural strength of the final products, and this effect is directly correlated with the concentration of nanoparticles.