Polymerase Chain Reaction In Tissues Research Articles

The Larynx is Protected from Secondary and Vertical Papillomavirus Infection in Immunocompetent Mice.

Mouse papillomavirus MmuPV1 causes both primary and secondary infections of the larynx in immunocompromised mice. Understanding lateral and vertical transmission of papillomavirus to the larynx would benefit patients with recurrent respiratory papillomatosis (RRP). To test the hypothesis that the larynx is uniquely vulnerable to papillomavirus infection, and to further develop a mouse model of RRP, we assessed whether immunocompetent mice were vulnerable to secondary or vertical laryngeal infection with MmuPV1. Larynges were collected from 405 immunocompetent adult mice that were infected with MmuPV1 in the oropharynx, oral cavity, or anus, and 31 mouse pups born to immunocompetent females infected in the cervicovaginal tract. Larynges were analyzed via polymerase chain reaction (PCR) of lavage fluid or whole tissues for viral DNA, histopathology, and/or in situ hybridization for MmuPV1 transcripts. Despite some positive laryngeal lavage PCR screens, all laryngeal tissue PCR and histopathology results were negative for MmuPV1 DNA, transcripts, and disease. There was no evidence for lateral spread of MmuPV1 to the larynges of immunocompetent mice that were infected in the oral cavity, oropharynx, or anus. Pups born to infected mothers were negative for laryngeal MmuPV1 infection from birth through weaning age. Secondary and vertical laryngeal MmuPV1 infections were not found in immunocompetent mice. Further work is necessary to explore immunologic control of laryngeal papillomavirus infection in a mouse model and to improve preclinical models of RRP. NA Laryngoscope, 134:2322-2330, 2024.

A comprehensive study of Helicobacter pylori infection: molecular analysis, antibacterial susceptibility, and histopathological examination.

Helicobacter pylori is a pathogen associated with gastroduodenal diseases. This study aimed; (i) to investigate H. pylori presence by invasive tests in adult dyspeptic patients, (ii) to determine antibiotic susceptibility and genotypic characteristics of the H. pylori isolates, and (iii) to investigate the relationship between the H. pylori genotypes and the histopathological findings. In this cross-sectional study, gastric biopsy samples from 208 adult dyspeptic patients were used for culture, tissue Polymerase Chain Reaction (PCR), and histopathological analysis. Antibiotic susceptibility of the H. pylori isolates was analyzed by gradient method. Analysis of the virulence genes was performed by monoplex PCR. Genetic profiles (from A to H) were created based on the virulence genes presence. Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR) was used for the genotyping of the H. pylori isolates. The mean age of the patients was 46 (± 15) years and 128 (61.5%) of them were female. H. pylori positivity was detected by culture, tissue PCR and histopathological examination in 59 (28.4%), 114 (54.8%) and 81 (38.9%) patients, respectively. The overall prevalence of H. pylori was found to be 63% (131/208). All H. pylori isolates were susceptible to tetracycline and amoxicillin. The resistance rates for metronidazole, clarithromycin, levofloxacin, and rifampicin were 67.2%, 27.9%, 34.4% and 13.11%, respectively. Multi drug resistance (MDR) was detected at the rate of 45.9% (28/61). While the most common virulence gene was cagA (93.44%), the least common was vacAm1 (23%). The predominant genetic profile was profile A (47.5%). ERIC-PCR results revealed a total of 26 different patterns. A high prevalence of H. pylori was detected in adult dyspeptic patients as in developing countries. It was observed significant genotypic heterogeneity and virulence gene diversity within the isolates. A considerable resistance rate detected against antibiotics such as clarithromycin, metronidazole, and levofloxacin, which are frequently used in the eradication of H. pylori, should be taken into consideration when creating regional empirical treatment regimens.

Clinical and immune features of human parvovirus B19 infection in allogeneic stem cell transplantation recipients: A retrospective monocentric study.

Human parvovirus B19 (B19V) infection is associated with pure red cell aplasia (PRCA) in immunocompromised patients; however, the spectrum of manifestations associated with B19V in allogeneic hematopoietic stem cell transplantation recipients (alloHSCT) has rarely been reported. In this study, we aimed to report clinical and immune features of B19V infection after alloHSCT. We retrospectively collected and analyzed clinical and microbiological data of all transplanted patients with B19V DNAmia or tissue infection detected by polymerase chain reaction (PCR) in our center from 2010 to 2021. We report 35 cases of B19V infections in 33 patients. Median time from transplant to B19V first PCR positivity was 6.9 months (interquartile range (IQR) [1.6-18.9]). No preferential immune profile, type of transplantation or conditioning was identified. Hematological impairment was the most frequent sign, followed by rash and fever. Unconventional clinical forms were also detected, such as acute myelitis and myositis. For some cases, the direct relationship between symptoms and B19V infection was difficult to prove but was suggested by targeted tissue PCR positivity. When hematological impairment was not at the forefront, reticulocytopenia helped to diagnose B19V infections. Treatment was mainly based on high dose intravenous immunoglobulin. Although hematological impairment was the most frequent sign, B19V can affect multiple targets and lead to atypical manifestations. Because of its heterogeneous clinical presentation, B19V infection is likely under-diagnosed. Diagnosis of unusual B19V organ involvement needs combination of arguments which can include targeted tissue PCR.

Data usefulness in determining cause of stillbirth in South Asia.

To evaluate the usefulness of data to determine cause of stillbirth in India and Pakistan. Prospective, observational study. Study hospitals in India and Pakistan. 200 fetal deaths with placental evaluation and minimally invasive tissue sampling (MITS) of internal organs and polymerase chain reaction (PCR) test for 75 pathogens. Data defined as useful to determine stillbirth causes. Placental pathology was the most useful to determine cause of stillbirth. Comparing placental and fetal weight with standard weights was useful in 44.5% and 48.5%, respectively. Lung histology was useful in 42.5%. Most of the other findings of internal organ histology were only occasionally useful. Signs of abruption, by maternal history or placental evaluation, were always deemed useful. Placenta, brain and cord blood PCR were also useful, but less often than histology. Based on this analysis, maternal clinical history, placental histology and fetal examination were most informative. Comparing the placental and fetal weights with recognised standards was useful in nearly half the cases. Fetal tissue histology and PCR were also informative. Of all the potential tests of MITS-obtained specimens, we would first recommend histological evaluation of the lungs, and using a multiplex PCR platform would determine pathogens in blood and brain/CSF. We recognise that this approach will not identify some causes, including some genetic and internal organ anomalies, but will confirm most common causes of stillbirth and most of the preventable causes of stillbirth in low- and middle-income countries.

Colonic cytomegalovirus DNA detection by polymerase chain reaction does not influence outcomes in inflammatory bowel disease and immunosuppressed cohorts.

Cytomegalovirus (CMV) colitis is associated with negative outcomes in inflammatory bowel disease (IBD) and immunosuppressed cohorts and therefore requires timely recognition for appropriate management. We aimed to evaluate the diagnostic tools for CMV colitis and their associations with clinical outcomes. A retrospective cohort study of patients in a metropolitan health service with colonic samples analysed for CMV between 2012 and 2022, stratified into IBD and non-IBD groups, was performed. The main outcome measures were the prevalence of positive and negative results for each CMV test, as well as need for colectomy, use of antiviral and hospital length of stay. Five hundred eighty-two biopsies from 418 patients were included; the median age was 36 years (interquartile range, 24-52 years) and 223 (53.3%) were men. Four hundred sixty-one (79.2%) biopsies were from patients with IBD and 121 (20.8%) were from those without IBD. There were similar proportions of positive CMV histology (IBD 5.9% and non-IBD 7.4%) and tissue CMV polymerase chain reaction (PCR) in the two groups (IBD 5.6% and non-IBD 5.0%), but within each group, results were discordant. Positive CMV histology was significantly associated with need for colectomy in the IBD group, while positive tissue CMV PCR was not. Positive CMV histology, and tissue and serum CMV PCR were all significantly associated with antiviral use. Positive serum CMV PCR was significantly associated with colectomy. Histopathology remains the most predictive tool in assessing CMV colitis, while qualitative tissue CMV PCR was found to have limited utility. Quantitative serum CMV PCR may be useful but requires further evaluation.

Clinical characteristics and diagnosis of intestinal tuberculosis in clinical practice at Thailand's largest national tertiary referral center: An 11-year retrospective review.

Diagnosing intestinal tuberculosis (ITB) is challenging due to the low diagnostic sensitivity of current methods. This study aimed to assess the clinical characteristics and diagnosis of ITB at our tertiary referral center, and to explore improved methods of ITB diagnosis. This retrospective study included 177 patients diagnosed with ITB at Siriraj Hospital (Bangkok, Thailand) during 2009-2020. The mean age was 49 years, 55.4% were male, and 42.9% were immunocompromised. Most diagnoses (108/177) were made via colonoscopy; 12 patients required more than one colonoscopy. Among those, the sensitivity of tissue acid-fast bacilli (AFB), presence of caseous necrosis, polymerase chain reaction (PCR), and culture was 40.7%, 13.9%, 25.7%, and 53.4%, respectively. Among patients with negative tissue histopathology, 4 (3.7%) and 13 (12.0%) were ITB positive on tissue PCR and culture, respectively. The overall sensitivity when all diagnostic methods were used was 63%. Seventy-six patients had stool tests for mycobacteria. The overall sensitivity of stool tests was 75.0%. However, when analyzing the 31 patients who underwent both endoscopy and stool testing, the sensitivity of stool testing when using tissue biopsy as a reference was 45.8%. Combining stool testing and tissue biopsy did not significantly increase the sensitivity compared to tissue biopsy alone (83.9% vs. 77.4%, respectively). Despite the availability of PCR and culture for TB, the overall diagnostic sensitivity was found to be low. The sensitivity increased when the tests were used in combination. Repeated colonoscopy may be beneficial. Adding stool mycobacteria tests did not significantly increase the diagnostic yield if endoscopy was performed, but it could be beneficial if endoscopy is unfeasible.

Effect of Antibiotic Therapy on the Sensitivity of Etiological Diagnostic Methods in Patients with Infective Endocarditis after Surgery

Aim. Assessment of impact of the duration of preoperative antimicrobial therapy (AMT) on the sensitivity of microbiological examination and polymerase chain reaction (PCR) of blood/tissues of resected valves in operated patients with infective endocarditis (IE).Materials and methods. 52 operated patients with active IE were included prospectively (Duke criteria, 2015). All patients underwent microbiological examination of blood before admission to the cardiac surgery hospital, as well as parallel simultaneous microbiological examination and PCR of blood/tissues of excised valves, followed by Sanger sequencing. The duration of preoperative treatment was calculated from the first day of AMT according to IE diagnosis to the day of surgery.Results. The causative agent of IE was established in 84.6% (n=44) patients by means of complex etiological diagnosis. A significant decrease in the sensitivity of microbiological examination of venous blood was revealed when performed in the period before and after hospitalization to a surgical hospital (up 44.2% to 17.3%, p<0.05). When comparing microbiological examination of blood/tissues of resected valves and PCR of blood/tissues of resected valves, molecular biological methods demonstrated the greatest sensitivity, with a great advantage when examining the tissues of resected valves (17.3% and 19.2% vs. 38.5% and 75.0%, respectively; p<0.001). The microbiological examination of venous blood performed at an early date before admission to the cardiac surgery hospital was comparable in sensitivity to the PCR blood test performed at a later date after prolonged AMT, and significantly less sensitive in relation to the PCR of resected valve tissues [44.2% and 38.5% (p>0.05) vs. 75.0% (p<0.05)]. In course of AMT 1-28 days, there were comparable results of microbiological examination with PCR blood examination and significantly better results of PCR of resected valve tissues [31.0% and 34.5% and 41.4% (p>0.05) vs 72.4% (p<0.001), respectively], and with AMT ≥ 29 days, microbiological examination of any biological material was negative in all patients, and PCR of blood/tissues of resected valves retained high sensitivity (0% and 0% vs. 34.8% and 78.3%, respectively; p<0.01).Conclusion. Long-term preoperative AMT significantly reduced the sensitivity of microbiological examination of resected valve blood/tissue in operated patients with IE, whereas PCR of resected valve blood/tissue was highly sensitive even with preoperative AMT for more than 29 days.

Synbiotics intake improves disturbed metabolism in a rat model of high fat diet-induced obesity; A potential role of adipose tissue browning

Browning of white adipose tissue (WAT) is currently considered a potential therapeutic approach to treat or prevent diet-induced obesity. Synbiotics have protective effects against diet-induced obesity; however, its role in adipose tissue browning has been less investigated. to study the possible effect of synbiotics intake on browning of WAT in obese rats. Twenty-four adult male Wistar rats were randomly divided into four groups; normal diet (ND) control group, high fat diet (HFD) group, ND group receiving synbiotics, and HFD group receiving synbiotics. After eight weeks, all rats were sacrificed; and samples (blood, WAT, brown adipose tissue, and liver) were collected. Lipid profile, liver enzymes, fasting glucose, and fasting insulin levels were measured. The expression of browning-related genes: uncoupler protein-1 (UCP-1), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), and peroxisome proliferator-activated receptors gamma (PPARγ) were measured by real-time polymerase chain reaction (PCR) in adipose tissues. Fibroblast growth factor 21 (FGF21) protein level was measured in serum, adipose and liver tissues, and FGF21 receptor expression was performed by real-time PCR in adipose tissues. ynbiotics intake was associated with improvement in lipid profile, liver enzymes, and insulin sensitivity in HFD rats. Moreover, the intake was associated with higher gene expression of brown adipocyte-specific markers. As for the FGF21 and its receptor, intriguing results were obtained that needs further in-depth studies. synbiotics might protect against diet-induced obesity through induction of thermogenic genes resulting in brown-like adipocyte phenotype in WAT.

Autopsy Histopathologic Cardiac Findings in 2 Adolescents Following the Second COVID-19 Vaccine Dose

Autopsy Histopathologic Cardiac Findings in 2 Adolescents Following the Second COVID-19 Vaccine Dose

Comparable Results of Helicobacter pylori Antibiotic Resistance Testing of Stools vs Gastric Biopsies Using Next-Generation Sequencing

Comparable Results of Helicobacter pylori Antibiotic Resistance Testing of Stools vs Gastric Biopsies Using Next-Generation Sequencing

Combining Direct PCR Technology and Capillary Electrophoresis for an Easy-to-Operate and Highly Sensitive Infectious Disease Detection System for Shrimp.

Infectious diseases are considered the greatest threat to the modern high-density shrimp aquaculture industry. Specificity, rapidity, and sensitivity of molecular diagnostic methods for the detection of asymptomatic infected shrimp allows preventive measures to be taken before disease outbreaks. Routine molecular detection of pathogens in infected shrimp can be made easier with the use of a direct polymerase chain reaction (PCR). In this study, four direct PCR reagent brands were tested, and results showed that the detection signal of direct PCR in hepatopancreatic tissue was more severely affected. In addition, portable capillary electrophoresis was applied to improve sensitivity and specificity, resulting in a pathogen detection limit of 25 copies/PCR-reaction. Juvenile shrimp from five different aquaculture ponds were tested for white spot syndrome virus infection, and the results were consistent with the Organization for Animal Health’s certified standard method. Furthermore, this methodology could be used to examine single post larvae shrimp. The overall detection time was reduced by more than 58.2%. Therefore, the combination of direct PCR and capillary electrophoresis for on-site examination is valuable and has potential as a suitable tool for diagnostic, epidemiological, and pathological studies of shrimp aquaculture.

Severe Acute Respiratory Syndrome Coronavirus 2 Is Detected in the Gastrointestinal Tract of Asymptomatic Endoscopy Patients but Is Unlikely to Pose a Significant Risk to Healthcare Personnel.

Background and AimsRecent evidence suggests that the gut is an additional target for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, whether SARS-CoV-2 spreads via gastrointestinal secretions remains unclear. To determine the prevalence of gastrointestinal SARS-CoV-2 infection in asymptomatic subjects, we analyzed gastrointestinal biopsy and liquid samples from endoscopy patients for the presence of SARS-CoV-2.MethodsWe enrolled 100 endoscopic patients without known SARS-CoV-2 infection (cohort A) and 12 patients with a previous COVID-19 diagnosis (cohort B) in a cohort study performed at a regional hospital. Gastrointestinal biopsies and fluids were screened for SARS-CoV-2 by polymerase chain reaction (PCR), immunohistochemistry, and virus isolation assay, and the stability of SARS-CoV-2 in gastrointestinal liquids in vitro was analyzed.ResultsSARS-CoV-2 ribonucleic acid was detected by PCR in the colonic tissue of 1/100 patients in cohort A. In cohort B, 3 colonic liquid samples tested positive for SARS-CoV-2 by PCR and viral nucleocapsid protein was detected in the epithelium of the respective biopsy samples. However, no infectious virions were recovered from any samples. In vitro exposure of SARS-CoV-2 to colonic liquid led to a 4-log–fold reduction of infectious SARS-CoV-2 within 1 hour (P ≤ .05).ConclusionOverall, the persistent detection of SARS-CoV-2 in endoscopy samples after resolution of COVID-19 points to the gut as a long-term reservoir for SARS-CoV-2. Since no infectious virions were recovered and SARS-CoV-2 was rapidly inactivated in the presence of colon liquids, it is unlikely that performing endoscopic procedures is associated with a significant infection risk due to undiagnosed asymptomatic or persistent gastrointestinal SARS-CoV-2 infections.

Epigenetic silencing of ZBTB28 promotes renal cell carcinogenesis.

Zinc finger and BTB domain-containing protein 28 (ZBTB28) is a potential tumor suppressor for some cancers. However, its epigenetic regulation and functions in renal cell carcinoma (RCC) remain to be elucidated. The expression of ZBTB28 mRNA was analyzed by semi-quantitative reverse transcription polymerase chain reaction (PCR) in nine RCC cell lines and normal kidney tissues. Methylation status of ZBTB28 promoter was assessed by methylation-specific PCR in RCC cell lines, primary RCC, tumors and adjacent tissues. The involvement of ZBTB28 in cell proliferation and migration was investigated. ZBTB28 promoter was hypermethylated in 88.9% (8/9) of RCC cell lines with reduced ZBTB28 mRNA expression, and could be reversed by DNA methyltransferase inhibitors. The methylation of ZBTB28 promoter was detected in 73.5% (36/49) of primary RCC tissues, compared with 7.1% (1/14) in normal tissues. Overexpression of ZBTB28 significantly inhibited RCC cell proliferation and migration, and induced apoptosis. Further analyses revealed that ZBTB28 upregulation could inhibit multiple oncogenic signaling transduction pathways. ZBTB28 is frequently silenced by promoter methylation in RCC pathogenesis and functions as a novel tumor suppressive gene. ZBTB28 may be a potential target for the development of RCC therapeutic strategies.

Investigation of Cytomegalovirus in Intestinal Tissue in a Country With High CMV Seroprevalence.

In Turkey, cytomegalovirus (CMV) seropositivity has been reported to be high, between 85 and 100%. CMV has been responsible for disease exacerbation in inflammatory bowel disease (IBD). We aimed to evaluate the presence of CMV in intestinal tissue by immunohistochemical staining in IBD and non-IBD patient groups, in a country with high CMV seroprevalence. In this prospective cross-sectional study, the presence of intestinal CMV was investigated with tissue immunohistochemistry (IHC) staining, which is accepted as the gold standard method, and with polymerase chain reaction (PCR) in tissue and blood. Patients (≥18 years old, n = 189) who had a colonoscopic biopsy between January and May 2017 were included in the study at our hospital. Clinical, laboratory, endoscopic, and histopathological data of patients were assessed by dividing them into IBD (n = 34) and non-IBD (n = 155) groups. In this study, 567 colonic biopsy samples from 189 patients were evaluated. Tissue IHC staining was positive for 3 (1.58%) non-IBD patients. One of them was diagnosed as CMV ileitis. CMV DNA was also detected in 14 plasma (7.40%, <80-469 copies/mL) and 20 tissue samples (10.69%, 7-15 289 copies/mL). Tissue IHC staining is accepted as the gold standard for CMV ileitis, and the sensitivity and specificity of tissue PCR was 33% and 89.67%, while the sensitivity and specificity of plasma PCR was 66.66% and 93.54%, respectively. Although CMV seroprevalence is high in Turkey, CMV ileitis was diagnosed in only one non-IBD patient (0.53%). Compared to tissue IHC staining, the sensitivity of tissue and blood CMV PCR was low while their specificity was higher.

Alterations of Glutathione and GSTM1 Mutation Induce Tumor Metastasis and Invasion Via EMT Pathway in Breast Cancer Patients

Objectives: Alteration in the Glutathione (GSH) and Glutathione S-Transferase (GST) family lead to various disorders including breast cancer. However, the role of GSH and GSTM1 in the onset of breast cancer is still not fully elucidated. In the present study we observed considerable deficiency in the levels of glutathione and genetic mutation in the GSTM1 enzyme that influence susceptibility to breast cancer metastasis and invasion via EMT pathway. Methods: GSTM1 genotype was identified by multiplex polymerase chain reaction (PCR), real time (RT)-PCR and western blotting in breast tumor samples and adjacent normal control tissue (ANCT) samples. The endogenous glutathione levels were determined by high performance liquid chromatography (HPLC).The tumor metastasis, invasion and epithelial-mesenchymal transition (EMT) biomarkers were determined by RT-PCR. Results: In present study genotyping analysis of GST investigated that genetic mutation in GSTM1 was detected in breast cancer tissue samples. mRNA and protein expression of GSTM1 was significantly downregulated in tumor samples as compared to adjacent normal control tissue (ANCT) samples in breast cancer patients. Significant reduction of total glutathione (GSHt P<0.05) was observed among correlation with patient ages, stages and histological grades of breast cancer patients. Additionally, downregulation of GSTM1 promotes EMT pathway that leads to enhanced the expression of tumor proliferation, invasion and metastasis in breast cancer patients (p<0.05). Conclusion: The present findings suggest that GSTM1 genotype could be a potential biomarker for breast cancer pathogenesis. Keywords: Breast cancer, Glutathione, Glutathione S-Transferase M1, Invasion, Metastasis, Proliferation

Post-COVID mucormycosis: Ascertainment of the pathological diagnostic approach.

Post-COVID mucormycosis: Ascertainment of the pathological diagnostic approach.

Utility of flow cytometry and gene rearrangement analysis in tissue and blood of patients with suspected cutaneous T‑cell lymphoma.

Cutaneous T‑cell lymphoma (CTCL) is difficult to diagnose at an early stage. Current diagnostic tools include clinical examination, histomorphologic analysis, immunohistochemistry, flow cytometry of peripheral blood and/or lesional tissue, and evaluation of T‑cell receptor (TCR) clonality by gene rearrangement analysis (TCRGR). Advances in genomic sequencing, including high‑throughput sequencing (HTS), can be used to identify specific clones of rearranged TCR genes. Even with all of these tools, CTCL can take as long as a decade to definitively diagnose, potentially delaying treatment options and causing patient anxiety. This study aimed to evaluate the performance of the various ancillary testing modalities used to diagnose early‑stage CTCL. In a subset of patients the performance of HTS was compared to flow cytometry and conventional TCRGR analysis via polymerase chain reaction (PCR). Fifty‑five patients, with a total of 68 skin biopsies and peripheral blood draws, were evaluated using flow cytometry, PCR‑TCRGR, and HTS‑TCRGR to determine the sensitivity and specificity of each ancillary test. In tissue biopsies, flow cytometry (64%), PCR (71%) and HTS (69%) shared similar sensitivities; flow cytometry had the highest specificity(93%), followed by HTS(86%) and PCR(76.9%). However, flow cytometry and PCR had insufficient DNA quantities in 29and15%of the specimens, respectively. Peripheral blood testing was less sensitive than tissue testing (flow cytometry 14%,PCR41%, HTS33%); in peripheral blood, HTS was the most specific test (flow cytometry,70%; PCR,62.5%; and HTS,100%). HTS is a highly specific molecular test for identifying CTCL in peripheral blood and skin biopsy specimens; however, our findings suggest a need for a continued search for more sensitive tests for early‑stage CTCL.

Hepatic pathology in patients dying of COVID-19: a series of 40 cases including clinical, histologic, and virologic data

The novel coronavirus SARS-CoV-2 (coronavirus disease 19, or COVID-19) primarily causes pulmonary injury, but has been implicated to cause hepatic injury, both by serum markers and histologic evaluation. The histologic pattern of injury has not been completely described. Studies quantifying viral load in the liver are lacking. Here we report the clinical and histologic findings related to the liver in 40 patients who died of complications of COVID-19. A subset of liver tissue blocks were subjected to polymerase chain reaction (PCR) for viral ribonucleic acid (RNA). Peak levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were elevated; median ALT peak 68 U/l (normal up to 46 U/l) and median AST peak 102 U/l (normal up to 37 U/l). Macrovesicular steatosis was the most common finding, involving 30 patients (75%). Mild lobular necroinflammation and portal inflammation were present in 20 cases each (50%). Vascular pathology, including sinusoidal microthrombi, was infrequent, seen in six cases (15%). PCR of liver tissue was positive in 11 of 20 patients tested (55%). In conclusion, we found patients dying of COVID-19 had biochemical evidence of hepatitis (of variable severity) and demonstrated histologic findings of macrovesicular steatosis and mild acute hepatitis (lobular necroinflammation) and mild portal inflammation. We also identified viral RNA in a sizeable subset of liver tissue samples.

Cerebrospinal fluid PCR: A new approach for the diagnosis of CNS sporotrichosis.

Cases of meningoencephalitis have increased in the zoonotic hyperendemia of sporotrichosis in the state of Rio de Janeiro, Brazil. The gold standard for the diagnosis of sporotrichosis is the isolation of Sporothrix spp. from clinical specimens, not always possible from the cerebrospinal fluid (CSF) of these patients, since fungus recovery in this specimen is difficult in most cases. This limitation led us to pursue a new approach on central nervous system (CNS) sporotrichosis diagnosis based on existing molecular methodologies for the detection of Sporothrix spp. in skin samples. Kano and colleagues (2003) designed species-specific primers for polymerase chain reaction (PCR) based on Sporothrix schenckii sensu lato chitin synthase 1 (CHS1) gene sequence and applied it in skin biopsy paraffin block. Hu and colleagues (2003) used a nested PCR in human clinical samples and samples from infected mice, with the 18S rRNA gene sequence as target. The assay was successfully used to detect S. schenckii DNA from strains from different areas of the world. However, Mendoza and colleagues compared the previously described nested PCR with conventional diagnostic methods, and the molecular methodology presented lower efficacy. Liu and colleagues, using the primer pair S2-R2 targeting the CHS1 gene in the PCR of biopsy tissue, verified positive results in 25 out of 30 cases (83.3%). The nested PCR targeting the partial sequence of the 18S rRNA gene was the best choice in terms of sensitivity due to a low fungal burden in CSF.

Differential diagnosis of the granulomatous appendicitis: Retrospective analysis of 16 cases.

This study aims to present the usability of real-time polymerase chain reaction (PCR) and interferon-gamma release assay (IGRA) in the differential diagnosis of granulomatous appendicitis (GAp), especially in areas where tuberculosis (TB) is endemic. Sixteen patients underwent appendectomy with presumed diagnosis of acute appendicitis were retrospectively analyzed for histopathological diagnosis of GAp. Real-time PCR method was used to show the whether presence of DNA of the tubercle bacilli in paraffin-embedded tissue blocks. IGRA test was used to investigate whether tubercle bacilli- specific interferon gamma was present in peripheral blood. Sixteen patients (male: 10 female: 6) aged between 21 and 82 years were included in this study. All patients had acute appendicitis and three of them also had appendiceal perforation. Histopathologically, necrotizing granulomatous inflammation was detected in all appendectomy specimens. Acid-fast bacilli were not detected in any of the pathology slides stained with Ehrlich-Ziehl-Neelsen. Real-time PCR was studied in paraffin-embedded tissue blocks of all patients with GAp, but the TB bacilli DNA was amplified in only three patients. IGRA test was studied in peripheral blood samples of 12 patients with GAp and results were as follows: negative (n=9), positive (n=2) and indeterminate (n=1). We believe that the use of anamnesis, histopathological findings, tissue PCR, blood IGRA and clinical findings together are important for differential diagnosis of GAp, especially where TB is endemic. We also suggest that all appendectomy specimens should be sent to the laboratory for histopathological evaluation even if specimens appear macroscopically normal.