Serological Tests Research Articles

Sonographic signs of abdominal neoplasms in feline uveitis

Feline uveitis is a common inflammatory disease of the vascular membrane of the eye. Damage to the uveal tract can be caused by a variety of causes, including systemic diseases, autoimmune processes, viral and bacterial infections, parasitic diseases, and oncological pathologies. Differential diagnosis of etiological factors is difficult and requires a comprehensive examination of the animal: careful collection of anamneses in order to exclude a traumatic factor, laboratory tests, serological tests to detect viral infections and parasitic infestations, visual diagnostic examination to diagnose systemic diseases and search for the oncological process. The research was conducted in 2023-2024 on the basis of the Department of Diseases of small domestic, laboratory and exotic animals, as well as the laboratory of "Oncology, Ophthalmology and Biochemistry of Animals" of the Federal State Budgetary Educational Institution "ROSBIOTECH". The aim of the study was to substantiate the use of sonographic and morphological research methods in the differential diagnosis of the etiology of feline uveitis. During the study, in 20.8% of cases (15 cats), sonographic examination of the abdominal cavity allowed to determine the cause of uveitis. We found: thickening of the muscular layer of the intestinal wall with partial or complete loss of layer differentiation, a local increase in the echogenicity of the surrounding adipose tissue, signs of mechanical obstruction of the proximally affected area, diffuse changes in mesenteric lymph nodes, diffuse focal changes in the liver and spleen, a volumetric neoplasm in the abdominal cavity located caudal to the right kidney, moderate nephromegaly and diffuse changes with violation of the differentiation of the cortical and cerebral layers. According to the results of morphological examination of the biopsy material, the diagnosis of large cell lymphoma was established in all cases. Uveitis in this group of cats is attributed to ophthalmopathy associated with paraneoplastic syndrome.

Serologic Testing of US Blood Donations to Identify Severe Acute Respiratory Syndrome Coronavirus 2 and Other Coronaviruses, December 2019 to July 2020.

The first coronavirus disease 2019 (COVID-19) case in the United States was recognized on 19 January 2020, but the time of introduction of the virus into the United States is unknown. An existing sample cohort was examined for serologic evidence of early severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. A repository of 46 120 samples from healthy routine blood donors, representing 46 states and the District of Columbia, was tested for total antibodies to SARS-CoV-2 nucleocapsid (anti-N) using a commercial test. All reactive samples were further tested using an experimental receptor-binding domain (RBD)-specific immunoglobulin G (IgG) enzyme-linked immunosorbent assay. Further testing was also conducted for anti-spike (anti-S) antibodies by commercial tests, experimental anti-S immunologic blocking, and for antibodies to the 4 human cold coronaviruses. Anti-N reactivity was observed in 92 tested samples (0.2%), 91 of which had adequate volume for further testing; of these, 55 were confirmed positive by anti-RBD. None of these reactive findings were attributable to the other human coronaviruses tested. The confirmed-positive frequency increased over time paralleling patterns observed for COVID-19 cases reported in the United States (in contrast to stable patterns over time for the cold coronaviruses). Nine confirmed positive samples (0.07%) were identified among the 13 364 donations collected between 13 December 2019 and 22 January 2020. None of these early confirmed-positive samples were reactive by commercial anti-S tests suggesting very recent infection. The samples tested in this study were broadly representative of the United States, and all were from individuals who had successfully donated blood. The antibody-reactive results of this study suggest that SARS-CoV-2 was likely present in the United States before 19 January 2020.

Revised Diagnosis From Histiocytic Neoplasm to Optic Chiasm Glioblastoma After Genetic Analysis.

A 46-year-old man presented with left eye blurring. Automated visual field testing showed an incongruous right hemianopia, with sparing of the lower temporal quadrant in the right eye. MRI revealed foci of gadolinium enhancement in the optic chiasm and optic tracts. Serologic testing (including myelin oligodendrocyte glycoprotein and neuromyelitis optica antibodies) and cerebrospinal fluid analysis were negative. Whole-body PET/CT scan found no malignancy. Biopsy of the optic chiasm revealed a moderately cellular neoplasm composed of atypical, discohesive cells with enlarged nuclei, prominent eosinophilic nucleoli, and abundant vacuolated cytoplasm. Immunohistochemical stains for CD68 and S100 were positive, whereas those for GFAP, OLIG2, SOX10, and multiple others were negative, supporting a diagnosis of histiocytic neoplasm. Five weeks later, results became available from next-generation sequencing targeting the coding regions of hundreds of malignancy-associated genes and select introns. Alterations associated with histiocytic neoplasms (i.e. BRAF and MAP2K1 mutations) were absent. However, there was a nonsense mutation in the PTEN gene, a hotspot mutation in the TERT gene promotor, and focal amplifications of the CDK4 and MDM2 genes. Additionally, there was chromosome 6q loss, 7 gain, and 10q loss. Based on these findings, the diagnosis was revised to glioblastoma, IDH-wildtype, CNS WHO grade 4. The patient began treatment with temozolomide while continuing radiation therapy. This case illustrates how next-generation sequencing can at times provide more accurate diagnostic information than standard tissue histopathology.

Primary Hydatid Cysts in the Extremities: A Systematic Review of the Literature.

Primary hydatid cysts (PHCs) in the extremities are uncommon, presenting in the majority of cases with atypical clinical features. Radical surgical excision remains the mainstay of treatment. The aim of our study was to accumulate the already published data on PHCs in the extremities in terms of demographic, diagnostic, and therapeutic aspects. Three electronic databases were meticulously searched for articles published until 2024. A total of 85 studies comprising 118 patients were finally included in our review. Sixteen patients (13.5%) were diagnosed with a hydatid cyst in their upper extremity, 94 (79.7%) with a PHC in the lower extremity, and eight (6.8%) with an echinococcal cyst in the axilla. Pain and swelling were the most frequent symptoms, whereas only two patients were completely asymptomatic. The mean lesion size was 11.6 ± 7.1 cm.Preoperative serology investigation was reported in 82 out of 118 (69.5%) patients; among them, 33 (44.6%) cases had a positive preoperative serology test. The vast majority of patients (96.6%) were treated with an interventional procedure either surgical or radiological, and only seven experienced postoperative complications. No anaphylactic reaction was described perioperatively. Although preoperative diagnosis of PHCs is challenging, they should be considered in the differential diagnosis of soft tissue lesions. Treatment strategies should be individualized on a patient basis, while radical surgical excision remains the gold standard treatment.

Analysis of Inflammatory Markers and Electroencephalogram Findings in Pediatric Patients with COVID-19: A Single-Center Study in Korea

Purpose: The Omicron variant wave spread rapidly from February 2022 in South Korea following the initial management of the coronavirus disease 2019 (COVID-19) outbreak. This study examined electroencephalogram (EEG) findings and serological inflammatory markers in pediatric patients with COVID-19 (Omicron variant).Methods: We retrospectively reviewed the medical records of 41 patients who presented at Gyeongsang National University Changwon Hospital between March and May 2022 and were diagnosed with COVID-19. All serological tests were performed within 24 hours of fever or seizure onset. Results: The median patient age was 3.6 years (range, 0.08 to 14.00), and the average hospital stay was 3.7 days (range, 1.0 to 7.0). Interleukin-6 (IL-6) levels were elevated above the normal range in all patients (median, 43.18 pg/mL; range, 7.0 to 190.0) and were higher among those who experienced seizures. Of the 41 total patients, 17 (41.5%; mean age, 5.4 years) visited the clinic for seizure. Three patients experienced prolonged seizures (lasting longer than 30 minutes) and received intravenous lorazepam, while eight presented with complex febrile seizures. Nine patients underwent EEG, of whom five exhibited abnormal initial findings. Linear regression demonstrated correlations between prolonged seizure duration and both serum IL-6 level and blood lymphocyte count.Conclusion: Numerous serological markers associated with the immune cascade were found to be elevated in children with COVID-19. Nevertheless, febrile seizures represent a relatively common neurological presentation among pediatric patients infected with Omicron variants. Consequently, COVID-19 infection exhibits both familiar and distinct characteristics regarding the mechanisms inducing seizures and fever in children.

The porcine circovirus 3 humoral response: characterization of maternally derived antibodies and dynamic following experimental infection.

Research on Porcine Circovirus 3 (PCV3) immunology is vital for understanding and controlling this virus. Previous studies primarily relied on field observations, but they have shown conflicting results about the immunological response against PCV3. This study helps fill those gaps by looking at how antibodies develop in pigs, especially those maternal-derived, and their impact in neonatal pigs preventing PCV3-associated disease in piglets. In addition, we look at the dynamics of antibodies in experimental infections mimicking infection in pigs in the grower-phase condition. Understanding this process can help to develop better strategies to prevent PCV3 infection. Also, this research found that PCV2 and PCV3 do not cross-react, which is crucial for serological test development and results interpretation. Overall, this work is essential for improving swine health and farming practices in the face of PCV3 infections.

Revisiting The Hygiene Theory; Hepatitis A And Tuberculosis Versus Atopy

Objectives: According to the hygiene hypothesis an inverse association between allergic sensitization and exposure to infections and has been reported. In this study, we investigated the relationship between atopy and TB and hepatitis A virus (HAV) infections in children. Methods: A cross-sectional study was performed and included 39 healthy children who were followed up with TB, 40 healthy children who were with HAV seropositive, and 30 healthy children who were seronegative for HAV and tuberculin skin test (TST) response as negative. Serological tests for HAV (anti-HAV immunoglobulin G), skin prick test (SPT) investigations for the detection of atopy, and TST were carried out. Results: The study included 39 (16 males, 23 females) with TB, 40 (16 males, 24 females) with HAV seropositive, and 30 (10 males, 20 females) healthy controls. There was no statistically significant difference between the groups in terms of age and gender (p>0.05). The SPT positivity was 28.2% (n=11) in the TB group, 15% (n=6) in the HAV group, and 30% (n=9) in the control group. There was no statistically significant difference between the groups in terms of SPT positivity (p=0.148). There was no statistically significant difference between the groups in terms of total serum IgE level (p=0.776). Conclusions: Our study does not support the hypothesis that HAV and TB suppress the development of atopy. We think that encountering infections during the immune maturation period is a condition that is protective in the development of atopy due to multifactorial reasons.

The Prevalence of Toxoplasma Gondii Infection in Duhok, Kurdistan Region, Iraq

Toxoplasmosis is a parasitic infection, with widespread gestational and congenital transmission rates globally, consequently, it is regarded as a public health concern and an overlooked medical condition. Human infection occurs through various routes, including the ingestion of oocysts found in cat feces, consumption of raw or undercooked meat containing the parasite, and vertical transmission from an infected pregnant mother to her fetus. Objective. The aim of this study is to determine the prevalence of Toxoplasma gondii infection among individuals in various age groups and genders in Duhok City. Methods. In this research, 2251 individuals of various ages and genders visited the central laboratory in Duhok Сity, Kurdistan Region, Iraq, and peripheral blood samples were taken from individuals to identify specific anti-Toxoplasma gondii IgM and IgG antibodies using serological test (ELISA test). Results. Based on the findings of this study, it was observed that the prevalence of toxoplasmosis among females with infections detected in both IgM and IgG was 0.3 % and 20.6 %, respectively, and in males, the rate of infection with IgG was found to be 0.3 %, while no infections were detected with IgM. Also, among female individuals, the study recorded a 0.3 % infection rate for toxoplasmosis, which encompassed both IgM and IgG cases. Conclusions. Based on this study, it can be concluded that Toxoplasma infection is more common in females than in males, chronic toxoplasmosis appears to be more prevalent than acute infection with the highest rate of acute infections was found in the age group of 21–40 years.

Diagnosis of membranous nephropathy with Anti-GBM glomerulonephritis: a case series report

BackgroundThe concomitant occurrence of membranous nephropathy and anti-glomerular basement (anti-GBM) disease has been previously described but is extremely rare. However, delayed recognition or misdiagnosis leads to delayed treatment, resulting in worse renal and patient outcomes.Case presentationWe present 3 patients with rapidly progressive glomerulonephritis (RPGN), anti-GBM and serum-positive M-type phospholipase A2 receptor (anti-PLA2R) antibody. Renal biopsies revealed PLA2R-associated membranous nephropathy with anti-GBM glomerulonephritis. We analyzed the clinical and pathological characteristics and discussed that the correct diagnosis of membranous nephropathy with anti-GBM should rely on a combination of renal biopsy findings and serological testing. Despite aggressive treatment, one patient received maintenance hemodialysis, one patient progressed to CKD 3 stage, and the other patient died of cerebral infarction.ConclusionThe simultaneous occurrence of membranous nephropathy and anti-GBM disease is extremely rare. The correct diagnosis of membranous nephropathy with anti-GBM relies on a combination of renal biopsy findings and serological testing. Early diagnosis is needed to improve the renal dysfunction.

First study of the detection of Human Herpes Virus-8 and major blood-borne viruses in iranian patients with SLE: A cross-sectional study

BackgroundSystemic lupus erythematosus (SLE) is an autoimmune disease caused by genetic and environmental factors such as viral infections. Genomic and serologic tests were applied to detect significant blood-borne viruses in SLE patients to determine whether there was a possible association between viral infections and SLE. MethodsAntibodies (Abs) against HHV-8, HCMV, EBV, HIV, HBV, and HCV in SLE patients suffering from SLE were assessed by ELISA. In addition, HHV-8 DNA and HIV-1 RNA were quantified by real-time PCR, and the HCV and HBV genomes were detected using nested PCR. ResultsCompared to those in the control group, a high prevalence of anti-HHV-8 (p < 0.0001), anti-HCMV (p = 0.014), and anti-EBV (p = 0.017) Abs was detected in SLE patients. HHV-8, HIV, HCV, and HBV genomic tests were negative in both groups, while only 1.1 %, 2.2 %, and 1.1 % of SLE patients were positive for anti-HIV, anti-HCV Abs, and HBsAg, respectively. The most frequent major complaint in patients was arthralgia (76.7 %). ConclusionsThe increased prevalence of anti-HHV-8 Abs may not be related to the natural history of infection but to molecular mimicry. Increased anti-HCMV and anti-EBV Abs may also be associated with the development of SLE and may play direct or indirect roles in such infections or molecular mimicry. Since arthralgia is the most common symptom in SLE patients, the presence of these symptoms in any patient is a suggestive clue for the diagnosis of SLE. Defining the typical pattern of SLE in divergent nations with distinct environmental and geographical factors can be beneficial for obtaining a prompt diagnosis.

Structural Insights on Cross-Reactivity of Mite Allergens with Helminth Proteins

Updated notions about the so-called hygiene hypothesis consider now that helminths may have influence in the training of the immune system during childhood. Considering the similar type of immune response between helminth infections and allergic illnesses, the objective of this study was to evaluate how structural and functional conservation between house-dust mite allergens and their helminth orthologs might contribute to the cross-induction of IgE responses in allergies and helminthiasis. Amino acid sequences from group-1, -2, -5, -9, -10, -18, -21, and -23 allergens of the house dust mite Dermatophagoides pteronyssinus were retrieved from curated databases, and orthologs were identified in other mite species and different helminth parasites. We also assessed structural, conservational, functional, and immunologic relationships between these major mite allergens and their helminth counterparts. De novo 3D-modelling, B-cell epitopes prediction, structural conservation, and docking analyses were analyzed by Robetta platform, ElliPro and CBTope, RaptorX, and Z-Dock, respectively. Our results extend previous findings on structural conservations between major allergens and parasite proteins and show that these conservations go beyond the well-known conservations and may account for the observed immunological cross-reactions. This understanding can contribute in the near future to the development of more specific serological testing for mite-induced allergies and helminthiasis.

Molecular Background of RhD-positive and RhD-negative Phenotypes in a Saudi Population.

The RHD gene is one of the most complex blood group genes. The molecular background of the RHD gene in RhD-negative and RhD-positive individuals varies within and among different populations. Knowing the molecular basis of the RHD gene in a specific population is required to establish effective genotyping methods. While the molecular basis has been revealed in many ethnicities, such as Caucasians and Black Africans, it still requires elucidation in Arabs. The aim of this study was to gain insights into the molecular basis of RhD-positive and RhD-negative phenotypes in Saudi donors. Conventional serological tests were used to determine the Rh phenotypes in 136 Saudi donors by typing D, C, c, E, and e antigens. Multiplex-PCR and Single Specific Primer-PCR were used to detect the presence of exons 3, 4, and 7 and the hybrid Rhesus box gene, respectively, in RhD-negative and/or RhD-positive samples. Of the 136 samples, 70 were RhD positive and 66 were RhD negative. None of the RhD-negative donors had any of the three tested exons, whereas the hybrid Rhesus box gene was detected in all, indicating the zygosity status of the RHD deletion allele. The hybrid Rhesus box gene was detected in 79% of the RhD-positive individuals, suggesting high frequencies of RHD-negative haplotypes. The study findings indicate that Saudis with the RhD-negative phenotype are likely to have an entire RHD deletion in the homozygous state. However, a more comprehensive analysis of variant RHD alleles in the Saudi population is required to implement effective and dedicated molecular RHD typing strategies.

Posicionamiento de la Sociedad Española de Infectología Pediátrica sobre el diagnóstico y tratamiento de la infección por Mycoplasma pneumoniae

Mycoplasma pneumoniae (MP) is a bacterium with particular characteristics that give rise to a broad clinical spectrum, and respiratory infection is the most frequent presentation. Infection by MP occurs in cyclical epidemics, and paediatricians in Spain have noticed an increase in cases since January 2024, establishing hospital registers to collect surveillance data (as it is not a notifiable disease in Spain). The diagnosis of infection by MP is made through serological testing and/or the detection of genetic material by means of polymerase chain reaction (PCR). Neither methods can differentiate between colonization and active infection, so a precise diagnosis is not possible and testing should only be requested in the case of high clinical suspicion. The role of antibiotherapy in infection by MP in its different clinical variants is not well defined. Most infections are self-limiting and mild, and there is insufficient evidence to support the use of antibiotherapy in these cases. Antibiotic treatment is justified in patients with risk factors for the development of severe disease (Down syndrome, anatomical or functional asplenia, immunosuppression), in hospitalized patients with respiratory infection and in patients with moderate or severe extrapulmonary forms. Taking into account aspects concerning the rational use of antimicrobials, the treatment of choice would be clarithromycin, with azithromycin as an alternative, reserving the use of doxycycline and levofloxacin for cases of antimicrobial resistance and/or infections of the central nervous system.

Characterization of Blood Group Variants in an Omani Population by Comparison of Whole Genome Sequencing and Serology.

Although blood group variation was first described over a century ago, our understanding of the genetic variation affecting antigenic expression on the red blood cell surface in many populations is lacking. This deficit limits the ability to accurately type patients, especially as serological testing is not available for all described blood groups, and targeted genotyping panels may lack rare or population-specific variants. Here, we perform serological assays across 24 antigens and whole genome sequencing on 100 Omanis, a population underrepresented in genomic databases. We inferred blood group phenotypes using the most commonly typed genetic variants. The comparison of serological to inferred phenotypes resulted in an average concordance of 96.9%. Among the 22 discordances, we identify seven known variants in four blood groups that, to our knowledge, have not been previously reported in Omanis. Incorporating these variants for phenotype inference, concordance increases to 98.8%. Additionally, we describe five candidate variants in the Lewis, Lutheran, MNS, and P1 blood groups that may affect antigenic expression, although further functional confirmation is required. Notably, we identify several blood group alleles most common in African populations, likely introduced to Oman by gene flow over the last thousand years. These findings highlight the need to evaluate individual populations and their population history when considering variants to include in genotype panels for blood group typing. This research will inform future work in blood banks and transfusion services.

A Paper-Based Multiplexed Serological Test to Monitor Immunity against SARS-COV-2 Using Machine Learning.

The rapid spread of SARS-CoV-2 caused the COVID-19 pandemic and accelerated vaccine development to prevent the spread of the virus and control the disease. Given the sustained high infectivity and evolution of SARS-CoV-2, there is an ongoing interest in developing COVID-19 serology tests to monitor population-level immunity. To address this critical need, we designed a paper-based multiplexed vertical flow assay (xVFA) using five structural proteins of SARS-CoV-2, detecting IgG and IgM antibodies to monitor changes in COVID-19 immunity levels. Our platform not only tracked longitudinal immunity levels but also categorized COVID-19 immunity into three groups: protected, unprotected, and infected, based on the levels of IgG and IgM antibodies. We operated two xVFAs in parallel to detect IgG and IgM antibodies using a total of 40 μL of human serum sample in <20 min per test. After the assay, images of the paper-based sensor panel were captured using a mobile phone-based custom-designed optical reader and then processed by a neural network-based serodiagnostic algorithm. The serodiagnostic algorithm was trained with 120 measurements/tests and 30 serum samples from 7 randomly selected individuals and was blindly tested with 31 serum samples from 8 different individuals, collected before vaccination as well as after vaccination or infection, achieving an accuracy of 89.5%. The competitive performance of the xVFA, along with its portability, cost-effectiveness, and rapid operation, makes it a promising computational point-of-care (POC) serology test for monitoring COVID-19 immunity, aiding in timely decisions on the administration of booster vaccines and general public health policies to protect vulnerable populations.

Evaluation of the correlation of serological and intradermal allergen testing with clinical history in 29 dogs with atopic dermatitis.

Limited information exists about the correlation between clinical history and positive serum (SAT) and intradermal allergen test (IDAT) results in atopic dogs. To evaluate the correlation between clinical history and SAT/IDAT results in atopic dogs. Twenty-nine client-owned dogs with nonseasonal atopic dermatitis with or without seasonal exacerbation were enrolled. IDAT, SAT (immunoglobulin (Ig)M antibody capture enzyme-linked immunosorbent assay [MacELISA] with bromelain CCD inhibitor) and clinical information collected in a questionnaire regarding seasonal variations in pruritus affecting the dogs were performed on the same day. Two independent investigators (Inv A and Inv B) recorded IDAT results. The kappa coefficients agreement for positive IDAT scores between Inv A and B was substantial. The agreement between IDAT and SAT results at different ELISA absorbance units (EAU) cut-offs (>79 and ≥300) was slight and fair for both investigators, respectively. A higher agreement was observed between IDAT and SAT (≥300 EAU) than between IDAT and SAT (>79 EAU) with the exception of mite and flea allergens. There was a statistically significant association between clinical history and positive IDAT results for seasonal allergens (Inv A and Inv B, p = 0.016). There was no significance between positive SAT results and clinical history. Five (IDAT) and 12 of 13 (SAT) atopic dogs without clinical seasonal exacerbation showed positive results for seasonal allergens. The agreement between IDAT and SAT ≥300 EAU results was fair and the agreement between IDAT and SAT >79 EAU results was slight for all allergens. Only positive IDAT results significantly correlated with clinical history.

THE STUDY OF PERFORMANCE AND DIAGNOSTIC EFFICACY OF WIDAL TEST AND STOOL CULTURE IN THE DIAGNOSIS OF TYPHOID FEVER AMONG SUSPECTED PATIENTS IN LOW INCOME COUNTRIES : A COMPREHENSIVE SYSTEMATIC REVIEW

Background: Typhoid fever is a significant health challenge in low- and middle-income countries (LMIC) due to inadequate access to clean water and sanitation infrastructure. The prevalence of typhoid fever, as determined by the Widal test, has quadrupled between 2014 and 2018, with sub-Saharan Africa having the highest infection load. Inadequate diagnosis and treatment are crucial to prevent complications. Rapid serological tests, lack of standard laboratory practices, and limited disease surveillance systems contribute to the uncertainty in disease burden. Methods: Following PRISMA 2020 guidelines, this systematic review concentrated on full-text English literature published between 2014 and 2024. Editorials and review articles that appeared in the same journal as the submission were not accepted without a DOI. The literature was assembled using a variety of online databases, including ScienceDirect, PubMed, and SagePub. Result: Utilizing reliable resources including Science Direct, SagePub, and PubMed, the study examined around 800 papers. After seven pieces were determined to be relevant for methodical investigation, a more thorough examination of the complete material was conducted. Conclusion: Diagnostics for typhoid fever, a common illness in low- and middle-income countries, mostly depend on the Widal test. On the other hand, variables such as malaria parasitemia, antigen standardization, and patient population affect how accurate the test is. The suggested diagnostic strategy identifies Salmonella from blood, stool, and bone marrow cultures; this calls for significant upgrades to laboratory resources as well as continuous training.

A Case Series on Spotted Fever and Typhus Fever Seropositivity at National Center for Disease Control and Epidemiological Perspective.

Background: The rickettsioses, except for typhus fever and scrub typhus (ST), were not really recognized as distinct clinical entities until the early 20th century. Only when specific rickettsial serologic testing was introduced in the 1940s could the precise etiologies of various rickettsial diseases (RDs) be determined with certainty. Although ST is a well- recognized zoonotic disease entity, but non-scrub typhus rickettsial infection like spotted fever group and typhus group are not well studied in India and are still underestimated. Methods: We report cases who had shown seropositivity of spotted fever and typhus fever RD in IgM and IgG ELISA whose samples were referred from various hospitals of Delhi/National Capital Region in which clinicians had strong suspicion of rickettsiosis other than ST or Weil-Felix test found positive for any of the OX2, 19, and K antigens. Results: We reported 18 cases of SFG and TGRD with mostly cases presented with fever followed by hepato-intestinal symptoms. Conclusion: The vast variability and nonspecific presentation of rickettsiosis in spotted and typhus fever at times have often made it difficult to diagnose clinically. Prompt antibiotic therapy shortens the course of the disease, lowers the risk of complications, and in turn, reduces morbidity and mortality owing to RDs. There is a distinct need for physicians and health care workers at all levels of care in India to be aware of the clinical features, available diagnostic tests and their interpretation, and the therapy for these infections.

Application of Interferon-γ Release Assay in the Assessment of T-Cell Immunity to SARS-CoV-2 Antigens in the Cohort of Pediatric Patients with Juvenile Idiopathic Arthritis.

Background: an accurate assessment of the immunity against SARS-CoV-2 can facilitate a better understanding and management of not only the recent coronavirus but similar pathogens as well. Objective: the aim of this study was to evaluate T-cell immunity with reference to antibody titers in a group of pediatric patients with autoimmune arthritides utilizing the widely known Interferon-γ Release Assay (IGRA). Materials and Methods: This study was conducted in the cohort of 55 children suffering from Juvenile Idiopathic Arthritis (JIA). This research analyzed the SARS-CoV-2 T-cell response measured by a specific quantitative IGRA, followed by a serological ELISA test measuring the presence and quantity of IgG, IgM, and IgA antibodies in serum. Results: The cellular response to SARS-CoV-2 measured by the IGRA test significantly correlated with the antibody titers, IgA (p < 0.00003, R = 0.537), IgG (p < 0.0001, R = 0.668), and IgG nucleocapsid protein (NCP) (p < 0.003, R = 0.0399), with no correlation with IgM levels. The antibody levels in patients receiving biological agents were significantly lower compared to the rest of the cohort (p = 0.0369), while traditional disease-modifying antirheumatic drugs had no such effect. Limitations: the main limitation of the research is the small sample size, mostly due to the specific cohort of patients and the lack of a healthy control. Conclusions: IGRA appears to be a viable tool in the accurate evaluation of T-cell responses to SARS-CoV-2, and serodiagnostics alone is not always sufficient in the assessment of immune responses.

Seroprevalence and Risk Factors of Brucellosis in Abattoir Workers in Fars Province, Iran

Background &amp; Objectives: Brucellosis remains an important occupational zoonotic disease, especially in developing countries. The disease is endemic in Iran and the Fars province. One of the main routes of brucellosis infection is at slaughterhouses, where the workers directly contact infected animals. This study was designed to estimate the seroprevalence of brucellosis among slaughterhouse workers in the Fars province, Iran. Materials &amp; Methods: Ninety blood samples were collected from workers of two livestock slaughterhouses (Marvdasht and Kazeroon), in Fars, Iran. The sera were assessed for the Rose Bengal test (RBT), as a screening test for brucellosis, and the positive samples were subjected to the Wright test. The positive Wright samples were finally tested for the 2 -mercaptoethanol (2 -ME) agglutination test. Results: Brucellosis prevalence was 13.33% using RBT and 4.44% of the workers showed active brucellosis. No significant relationship was found between the questionnaire variables and brucellosis tests; exceptionally, there was a relationship between the workers' statements regarding having had brucellosis and RBT (P=0.01). Conclusion : Our study highlights the practical application of serological tests, including RBT, Wright, and 2 - ME as a simple strategy to monitor brucellosis and to diagnose and treat its active form in endemic regions. Although a small frequency of the disease was found, it could cause significant health and economic damage to humans and animals in endemic areas. Furthermore, taking enough protective measures is highly recommended for slaughterhouse workers to prevent human brucellosis.