Tropheryma whipplei intestinal colonization in immunocompromised children in Iran: a preliminary study

2021 ◽  
Author(s):  
Saeed Shams ◽  
Niloofar Rezaie ◽  
Anna Beltrame ◽  
Lucia Moro ◽  
Chiara Piubelli ◽  
...  

Aim & method: Tropheryma whipplei causes Whipple’s disease. Children are reservoirs of this bacterium. The aim of this study was to investigate the presence of T. whipplei in children with immunodeficiency in central Iran from July 2018 to February 2019. Stool samples were tested by SYBR Green and Taq-Man real-time PCR assays. For confirmation, the isolated DNA was sequenced. Results: One hundred and thirty children were enrolled. Acute lymphocytic leukemia was the most reported immunodeficient disease (77%), followed by non-Hodgkin lymphoma and retinoblastoma. Thirteen (10%) children had T. whipplei DNA in the stool; 11.4% of the children under 5 years old were positive. Conclusion: This is the first study showing the circulation of T. whipplei in Iran.

2018 ◽  
Vol 24 (1) ◽  
pp. 101-108 ◽  
Author(s):  
Hagen Frickmann ◽  
Miriam Hanke ◽  
Andreas Hahn ◽  
Norbert G. Schwarz ◽  
Olfert Landt ◽  
...  

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 188
Author(s):  
Tanja Hoffmann ◽  
Andreas Hahn ◽  
Jaco J. Verweij ◽  
Gérard Leboulle ◽  
Olfert Landt ◽  
...  

This study aimed to assess standard and harsher nucleic acid extraction schemes for diagnostic helminth real-time PCR approaches from stool samples. A standard procedure for nucleic acid extraction from stool and a procedure including bead-beating as well as proteinase K digestion were compared with group-, genus-, and species-specific real-time PCR assays targeting helminths and nonhelminth pathogens in human stool samples. From 25 different in-house and commercial helminth real-time PCR assays applied to 77 stool samples comprising 67 historic samples and 10 external quality assessment scheme samples positively tested for helminths, higher numbers of positive test results were observed after bead-beating-based nucleic acid extraction for 5/25 (20%) real-time PCR assays irrespective of specificity issues. Lower cycle threshold values were observed for one real-time PCR assay after the standard extraction scheme, and for four assays after the bead-beating-based scheme. Agreement between real-time PCR results after both nucleic acid extraction strategies according to Cohen’s kappa ranged from poor to almost perfect for the different assays. Varying agreement was observed in eight nonhelminth real-time PCR assays applied to 67 historic stool samples. The study indicates highly variable effects of harsh nucleic acid extraction approaches depending on the real-time PCR assay used.


Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 656
Author(s):  
Konstantin Tanida ◽  
Andreas Hahn ◽  
Kirsten Alexandra Eberhardt ◽  
Egbert Tannich ◽  
Olfert Landt ◽  
...  

Microsporidiosis is an infection predominantly occurring in immunosuppressed patients and infrequently also in travelers. This study was performed to comparatively evaluate the diagnostic accuracy of real-time PCR assays targeting microsporidia with etiological relevance in the stool of human patients in a latent class analysis-based test comparison without a reference standard with perfect accuracy. Thereby, two one-tube real-time PCR assays and two two-tube real-time PCR assays targeting Enterocytozoon bieneusi and Encephalocytozoon spp. were included in the assessment with reference stool material (20), stool samples from Ghanaian HIV-positive patients (903), and from travelers, migrants and Colombian indigenous people (416). Sensitivity of the assays ranged from 60.4% to 97.4% and specificity from 99.1% to 100% with substantial agreement according to Cohen’s kappa of 79.6%. Microsporidia DNA was detected in the reference material and the stool of the HIV patients but not in the stool of the travelers, migrants, and the Colombian indigenous people. Accuracy-adjusted prevalence was 5.8% (n = 78) for the study population as a whole. In conclusion, reliable detection of enteric disease-associated microsporidia in stool samples by real-time PCR could be demonstrated, but sensitivity between the compared microsporidia-specific real-time PCR assays varied.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4762-4762
Author(s):  
Urshila Durani ◽  
Ronald S. Go

Abstract Background: Neutropenic fever is a common complication of therapy for many cancers. Previous studies have shown high rates of in-hospital mortality ranging from 10-14% (Chindaprasirt J., et al, Asian Pac J Cancer Prev 2013; Kuderer N. M., et al, Cancer 2006; Lal A., et al,Asian Pac J Cancer Prev2008; Lyman G. H., et al,Cancer 2010). However, outcomes have not been studied in recent years since the release of updated infectious disease guidelines and improvements in supportive care. Methods: We queried years 2009 to 2013 of the National Inpatient Sample to determine the incidence, mortality, and length of stay for neutropenic fever hospitalizations. The National Inpatient Sample is a nationally weighted sample of all hospital discharges in the United States, derived from discharge billing records from hospitals across the country. Patients aged 18 and older with a principal diagnosis of neutropenia [International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes 288.00 and 288.03] and associated fever (ICD-9-CM code 780.61) were included. Patients with multiple malignancies, no malignancies, or admitted for an obstetric procedure/complication were excluded. Baseline characteristics, associated infections, and in-hospital complications were analyzed using descriptive statistics. Mortality and length of stay were our primary outcomes. Multivariable logistic regression was performed to identify predictors of mortality and longer length of stay. Results: A total of156,132 admissions with neutropenic fever occurred between 2009 and 2013. The average incidence of hospitalization for neutropenic fever was 85 per 100,000 total admissions, and did not change significantly over time. The distribution of admissions according to major types of malignancy was: solid tumors (54%); non-Hodgkin lymphoma (20%); acute myeloid leukemia (12%); acute lymphocytic leukemia (4%); and multiple myeloma (4%). The overall mortality was 2% and did not change significantly over time. The median length of stay was 4 days (interquartile range, 3-7). Pneumonia was the most commonly diagnosed infection (9%), followed by urinary tract infection (7%), bacteremia (4%), skin/soft tissue infection (4%), and upper respiratory tract infection/bronchitis (3%). Diagnosis of a fungal infection was uncommon (2%). Acute renal failure was the most common complication (7%), while acute respiratory failure (2%) and cardiac or pulmonary arrest (<1%) were uncommon. In multivariable analysis, age >59, acute myeloid leukemia, acute lymphocytic leukemia, and chronic lymphocytic leukemia (versus solid tumors), pneumonia, fungal infection and weighted Elixhauser comorbidity index >14 were significant predictors of mortality (Table 1) and increased length of stay (Table 2). Race, insurance, median household income, non-Hodgkin lymphoma, chronic myeloid leukemia, and multiple myeloma (versus solid tumor), and intestinal infection were also predictors of increased length of stay but not mortality. Conclusions: Our study is the first to examine a nationally representative cohort of cancer patients in the hospital with neutropenic fever and identified a relatively low mortality rate. We identified age, underlying comorbidities, type of cancer, and type of infection as significant predictors of mortality. Given the low morbidity and mortality rate, further studies should be done to improve risk stratification of patients with neutropenic fever and prevent unnecessary hospitalization. Table 1 Predictors of in-hospital mortality in patients with neutropenic fever Table 1. Predictors of in-hospital mortality in patients with neutropenic fever Table 2 Predictors of length of stay > 2 days in patients with neutropenic fever Table 2. Predictors of length of stay > 2 days in patients with neutropenic fever Disclosures No relevant conflicts of interest to declare.


Author(s):  
Saeed Shams ◽  
Nilofar Rezaei ◽  
Anna Beltrame ◽  
Lucia Moro ◽  
Chiara Piubelli ◽  
...  

Background: Tropheryma whipplei is the causative pathogen of Whipple&rsquo;s disease and other acute and chronic manifestations. Children have been identified as reservoirs of this bacterium especially in low-middle income countries. No information is currently available on the dissemination of T. whipplei in Iran. Therefore, the aim of this study was to investigate the presence of T. whipplei in children with immunodeficiency. Methods: This cross-sectional study was performed from July 2018 to February 2019 in Qom province (central Iran). Stool samples were collected from immuno-compromised children. T. whipplei was tested by SYBR Green and Taq-Man Real-time PCR assays. For confirmation, sequencing of the isolated bacteria was done. Results: One hundred and 30 children with a mean age of 56.7 months were enrolled. Acute lymphocytic leukemia was the most reported immunodeficient disease (77%), followed by non-Hodgkin lymphoma and retinoblastoma. The majority of the children were undergoing chemotherapy during the study. Thirteen (10%) children had T. whipplei DNA in the collected stools. Sequencing results confirmed T. whipplei identification in all the cases. Eight out of 70 (11.4%) children under 5 years old resulted positive. Conclusion: This is the first study showing the circulation of T. whipplei among immunocompromised children in Iran. More epidemiological studies are needed to evaluate the prevalence of this pathogen in different risk groups in Iran and to increase the knowledge of its rare clinical manifestations.


Author(s):  
Jie Liu ◽  
Suporn Pholwat ◽  
Jixian Zhang ◽  
Mami Taniuchi ◽  
Rashidul Haque ◽  
...  

Shigella flexneri is prevalent worldwide and is the most common Shigella species in many countries. At least 19 S. flexneri serotypes exist, and serotype information is important for epidemiologic and vaccine development purposes. We evaluated the performance of real time PCR (PCR) assays for O-antigen modification genes to identify the major serotypes on isolates and direct stool samples. The assays were formulated into two multiplex panels: one panel included gtrII, gtrV, gtrX, oac, and wzx6 to identify S. flexneri serotype 2a, 2b, 3a, 5a, 5b, 6, and X, the other panel included ipaH, gtrI, gtrIc, gtrIV, to confirm Shigella detection and further identify S. flexneri serotype 1a, 1b, 1d, 3b, 4a, 4b, 7a, and 7b. We first evaluated 283 Shigella isolates and PCR serotyping demonstrated 97.0% (95% confidence interval 93.0% - 99.0%) sensitivity and 99.9% (99.9%-100%) specificity compared to conventional serotyping. The assays were then utilized on direct stool specimens. A quantitative detection algorithm was developed with a validation set of 174 Shigella culture positive stool samples, and further tested with a derivation set of 164 samples. The PCR serotyping on stool achieved 93% (89%-96%) sensitivity and 99% (99%-100%) specificity compared to serotyping. Most discrepancies were genotypic-phenotypic discordance, not genotypic failure. These real-time PCR assays provide an efficient and novel tool for S. flexneri serotype identification.


Pathogens ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1131
Author(s):  
Felix Weinreich ◽  
Andreas Hahn ◽  
Kirsten Alexandra Eberhardt ◽  
Torsten Feldt ◽  
Fred Stephen Sarfo ◽  
...  

As qualified microscopy of enteric parasitoses as defined by high diagnostic accuracy is difficult to maintain in non-endemic areas due to scarce opportunities for practicing with positive sample materials, molecular diagnostic options provide less investigator-dependent alternatives. Here, we compared three molecular targets for the real-time PCR-based detection of Cryptosporidium spp. From a population of 1000 individuals comprising both Ghanaian HIV (human immunodeficiency virus) patients and military returnees after deployment in the tropics, stool samples were assessed for Cryptosporidium spp. by real-time PCR targeting the small subunit ribosomal RNA (SSU rRNA) gene, the Cryptosporidium oocyst wall (COWP) gene, and the DnaJ-like protein gene (DnaJ), respectively. In declining order, sensitivity of 100% for the SSU rRNA gene PCR, 90.0% for the COWP PCR and 88.8% for the DnaJ PCR, respectively, as well as specificity of 99.6% for the COWP PCR and 96.9% for both the SSU rRNA gene PCR and the DnaJ PCR, respectively, were recorded. Substantial agreement (kappa value 0.663) between the three assays was observed. Further, an accuracy-adjusted Cryptosporidium spp. prevalence of 6.0% was calculated for the study population. In conclusion, none of the assessed real-time PCR assays were associated with perfect test accuracy. However, a combination of highly sensitive SSU rRNA gene PCR for screening purposes and more specific COWP PCR for confirmatory testing should allow reliable diagnosis of Cryptosporidium spp. in stool samples even in low prevalence settings.


Author(s):  
Manoj Raje ◽  
Karvita B. Ahluwalia

In Acute Lymphocytic Leukemia motility of lymphocytes is associated with dissemination of malignancy and establishment of metastatic foci. Normal and leukemic lymphocytes in circulation reach solid tissues where due to in adequate perfusion some cells get trapped among tissue spaces. Although normal lymphocytes reenter into circulation leukemic lymphocytes are thought to remain entrapped owing to reduced mobility and form secondary metastasis. Cell surface, transmembrane interactions, cytoskeleton and level of cell differentiation are implicated in lymphocyte mobility. An attempt has been made to correlate ultrastructural information with quantitative data obtained by Laser Doppler Velocimetry (LDV). TEM of normal & leukemic lymphocytes revealed heterogeneity in cell populations ranging from well differentiated (Fig. 1) to poorly differentiated cells (Fig. 2). Unlike other cells, surface extensions in differentiated lymphocytes appear to originate by extrusion of large vesicles in to extra cellular space (Fig. 3). This results in persistent unevenness on lymphocyte surface which occurs due to a phenomenon different from that producing surface extensions in other cells.


Sign in / Sign up

Export Citation Format

Share Document