Detection of viral antigen, IgM and IgG antibodies in cerebrospinal fluid of Chikungunya patients with neurological complications

BACKGROUND: During Chikungunya virus (CHIKV) epidemic in Nagpur, India, we identified some suspected Chikungunya patients with neurological complications. Early and cost-effective diagnosis of these patients remains problematic despite many new advanced diagnostic methods. A reliable diagnostic test, which could be performed in any standard pathology laboratory, would help to obtain definitive early diagnosis of CHIKV patients with neurological complications. In our laboratory, in-house ELISA protocol for viral antigen, immunoglobulin M (IgM) and IgG detection has been developed and assessed for the diagnosis of CHIKV patients with neurological complications. METHOD: Cerebrospinal fluid samples of forty-six patients who developed neurological symptoms within two months of CHIKV infections along with control subjects were included in the study and were analyzed for the presence of antigens and of IgM and IgG using an ELISA protocol. RESULTS: The ELISA method for antigen detection yielded 80% sensitivity and 87% specificity for the diagnosis of CHIKV patients with neurological complications. The sensitivity for detection of IgM 48% or IgG 63% was significantly lower than the antigen assay (80%). CONCLUSION: The detection of viral antigen in CSF of CHIKV patients with neurological complications by ELISA method gave a more reliable diagnosis than antibodies detection that can be used to develop an immunodiagnostic assay with increased sensitivity and specificity

Modelling of cerebral tuberculosis in BALB/c mice using clinical strain from patients with CNS tuberculosis infection

Background & objectives: Central nervous system (CNS) infection caused by Mycobacterium tuberculosis (MTB) is the most severe form of extrapulmonary tuberculosis (EPTB) due to a high level of mortality and morbidity. Limited studies are available on CNS-TB animal model development. The present study describes the development of a murine model of CNS-TB using a clinical strain (C3) isolated from the cerebrospinal fluid (CSF) of CNS-TB patients. Methods: Groups of mice were infected by the intravenous route with MTB C3 strain isolated from the CSF of CNS-TB patients. Brain and lung tissue were evaluated for bacterial burden, histopathology and surrogate markers of TB infection at 30 and 50 days post-infection. Results: Mice infected intravenously with MTB C3 strains showed progressive development of CNS disease with high bacillary burden in lungs at the initial stage (30 days), which eventually disseminated to the brain at a later stage (50 days). Similarly, high mortality (60%) was associated in mice infected with C3 strain compared to control. Interpretation & conclusions: The study showed development of a novel murine model of CNS-TB using the C3 strain of MTB that replicated events of extrapulmonary dissemination. The developed model would be helpful in understanding the pathogenesis of CNS-TB infection for the development of improved therapeutic interventions in future

Rapid Diagnosis and Simultaneous Identification of Tuberculous and Bacterial Meningitis by a Newly Developed Duplex Polymerase Chain Reaction

The present study describes the development and evaluation of a duplex polymerase chain reaction (DPCR) for diagnosis and simultaneous identification of tuberculous meningitis (TBM) and bacterial meningitis (BM) in a single reaction. A D-PCR with primers amplifying portions of the Mycobacterium tuberculosis IS6110 and the eubacteria 16SrDNA sequence in a same reaction mix was developed and tested on DNA extracted from 150 clinical CSF samples from different categories (TBM = 39, BM = 26, control infectious and non-infectious category = 85). The results indicate a clear differentiation between bands for eubacteria and M. tuberculosis with an analytical sensitivity of 103 cfu/ml for eubacteria and 102 cfu/ml for M. tuberculosis. When evaluated in clinical samples, D-PCR overall diagnosed 100 % confirmed TBM and 100 % confirmed BM cases with overall specificity of 96.5 %. D-PCR can be an effective tool for diagnosis and simultaneous identification of TBM or BM in a single PCR reaction. It saves time, cost, labour and sample amount and help in administration of appropriate antimicrobial therapy

Diagnosis of Chikungunya Fever in an Indian Population by an Indirect Enzyme-Linked Immunosorbent Assay Protocol Based on an Antigen Detection Assay: a Prospective Cohort Study▿

A Chikungunya virus (CHIKV) outbreak continues in India. Monitoring of the clinical features of CHIKV infection is an important component of assessing the disease process. Diagnosis is usually made by an immunoglobulin M (IgM)/IgG enzyme-linked immunosorbent assay (ELISA). However, these assays have extremely low sensitivities for the detection of infection in the majority of CHIKV patients during the acute stage of infection (during the 1 to 4 days after infection). In our laboratory, a sensitive ELISA protocol for antigen detection has been developed for the detection of CHIKV infection in the acute stage, and in the present study we assessed the usefulness of this ELISA-based system for the detection of CHIKV infection. We performed a prospective, double-blinded study of 205 Indian patients with suspected CHIKV infection in the Nagpur District. All patients underwent a full clinical assessment, and their serum samples were analyzed for the presence of antigens and of IgM and IgG by an ELISA protocol. In patients with CHIKV infection, the sensitivity of antigen detection was 85%, which was significantly higher (P < 0.001) than that of IgM (17%) or IgG (45%) detection. The sensitivity of IgM (20%) or IgG (25%) detection was significantly lower than that of the antigen assay (95%) for patients with acute infections (i.e., from day 1 to day 5 after infection). Antigen detection not only gives a positive confirmatory result in the early phase of the disease, but it is also useful in the prodromal and subclinical stage and may be useful for field applications for the rapid detection of CHIKV infection

Incidence and Clinical Outcome of Patients with Hypertensive Acute Ischemic Stroke: An Update from Tertiary Care Center of Central India

Introduction: We evaluated the incidence and clinical outcome of patients with hypertensive acute ischemic stroke (AIS) admitted to a tertiary care center in Central India. In addition, we examined the status of stroke biomarkers namely neuron-specific enolase (NSE), glial specific protein (S-100&beta;&beta;), and inter-&alpha;-trypsin inhibitor heavy chain 4(ITIH4) in the serum of patients suffering from AIS with hypertension (HTN) and without HTN. Methods: A total of 104 patients with AIS were enrolled for the study. Clinical outcome and stroke biomarker levels were evaluated in them at the time of hospital discharge and then followed at 12 months and 18 months after hospital discharge.&nbsp; Results: HTN is a major risk factor associated with 67%(70.104) of patients with AIS. Multivariate analysis suggests higher odds of 4.088(95%Cl, 0.721&ndash;23.179) and 2.437(95%Cl, 0.721&ndash;23.179) for 12 and 18 months outcome in patients with AIS and HTN, respectively. Serum NSE and S-100&beta;&beta; decreased at the time of discharge as compared to admission level in improved patients suffering from AIS with or without HTN, whereas levels of ITIH4 peptides 2 and 7 increased at the time of discharge (compared to its admission level) only in improved patients with AIS regardless of HTN or non-HTN condition. Conclusion: HTN is one of the major risk factors associated with higher risk of AIS as well as long-term unfavourable outcome after AIS in Central India region. NSE, S-100&beta;&beta;, and ITIH4 were found to be independent predictors of outcome in patients with AIS irrespective of HTN and non-HTN condition

Nested PCR Assay for Eight Pathogens: A Rapid Tool for Diagnosis of Bacterial Meningitis

Purpose Bacterial meningitis is a dreadful infectious disease with a high mortality and morbidity if remained undiagnosed. Traditional diagnostic methods for bacterial meningitis pose a challenge in accurate identification of pathogen, making prognosis difficult. The present study is therefore aimed to design and evaluate a specific and sensitive nested 16S rDNA genus-based polymerase chain reaction (PCR) assay using clinical cerebrospinal fluid (CSF) for rapid diagnosis of eight pathogens causing the disease. Methods The present work was dedicated to development of an in-house genus specific 16S rDNA nested PCR covering pathogens of eight genera responsible for causing bacterial meningitis using newly designed as well as literature based primers for respective genus. A total 150 suspected meningitis CSF obtained from the patients admitted to Central India Institute of Medical Sciences (CIIMS), India during the period from August 2011 to May 2014, were used to evaluate clinical sensitivity and clinical specificity of optimized PCR assays. Results The analytical sensitivity and specificity of our newly designed genus-specific 16S rDNA PCR were found to be C92 %. With such a high sensitivity and specificity, our in-house nested PCR was able to give 100 % sensitivity in clinically confirmed positive cases and 100 % specificity in clinically confirmed negative cases indicating its applicability in clinical diagnosis