A Hospital Based Study on Estimation of Adenosine Deaminase Activity (ADA) in Cerebrospinal Fluid (CSF) in Various Types of Meningitis

Herpes simplex viruses (1 and 2) and varicella-zoster virus infections in an adult population with aseptic meningitis or encephalitis: A nine-year retrospective clinical study

Three α-herpesviruses are known to be associated with central nervous system (CNS) infection; however, there are limited data on the incidence and clinical characteristics of α-herpesviruses CNS infections. This study aimed to assess the clinical manifestations, laboratory findings, and outcomes in patients with human herpes simplex virus 1 (HSV-1), human herpes simplex virus 2 (HSV-2), and varicella-zoster virus (VZV) CNS infections.We identified cases of HSV-1, HSV-2, and VZV CNS infections and reviewed their clinical and laboratory characteristics. The study population was drawn from patients with HSV-1, HSV-2, and VZV polymerase chain reaction positivity in cerebrospinal fluid (CSF) who visited Pusan National University Hospital between 2010 and 2018.During the 9-year study period, a total of 727 CSF samples were examined, with 72.2% (525/727) patients identified as having a CNS infection. Of 471 patients with aseptic meningitis and encephalitis, the causative virus was identified in 145 patients, and no virus was detected in 337 patients. A total of 15.2% (80/525) were diagnosed with one of the 3 herpesviruses as causative agents, 59 patients had meningitis, and 21 patients had encephalitis. Eleven patients with HSV-1, 27 patients with HSV-2, and 42 patients with VZV CNS infections were included. The distribution of cases by age showed different patterns depending on the type of herpesvirus infection. Compared with the HSV-1 group, the median age in the HSV-2 group was younger (HSV-1: 58 years; HSV-2: 38 years; P = .004), and patients with VZV infections showed a bimodal age distribution. Encephalitis was more common in the HSV-1 group, and HSV-1 infection was associated with a poor prognosis at discharge. CSF white blood cell counts were significantly lower in patients infected with HSV-1 (117 × 106 cells/L) than in patients infected with VZV (301 × 106 cells/L) (P = .008).These 3 herpesviruses are important causes of CNS infections regardless of immunologic status. HSV-1 infection was commonly associated with encephalitis and poor prognosis; HSV-2 and VZV CNS infections were associated with a low risk of mortality and neurological sequelae.

Miliary Brain Tuberculomas and Meningitis: Tuberculosis Beyond the Lungs

Tuberculosis remains one of the most common infectious diseases. Miliary presentation is a rare and possibly lethal form, resulting from massive lymphohaematogenous dissemination of Mycobacterium tuberculosis bacilli. The authors describe the case of a 47-year-old immunocompetent woman, diagnosed with miliary tuberculosis, with both lung and central nervous system involvement, who showed total recovery after starting anti-tuberculous drugs. The atypical neutrophilic-predominant pleocytosis and negative cerebrospinal fluid microbiological results made the diagnosis even more challenging. Since prognosis largely depends on timely treatment, recognition and prompt diagnosis is important. Thus, clinicians should be aware and treatment should be initiated as soon as the diagnosis is suspected.

Clinical characteristics and molecular epidemiology of children with meningitis in Tehran, Iran: a prospective study

The molecular epidemiology of meningitis in children is unclear in Iran, and data are scarce. We aimed to characterize its clinical and paraclinical features as well as to determine the distribution of genotype/capsular types of common bacterial meningitis agents in children in Iran. All children suspected to have meningitis aged 4 days to 15 years were enrolled onto a prospective cross-sectional study from January 2015 to September 2017. Diagnostic values of clinical features, cerebrospinal fluid and serum parameters were evaluated independently and in combination with each other by multivariate logistic regression to develop a diagnostic rule. Genotype/capsular types of all the isolates were determined by targeting serotype-specific genes with uniplex or multiplex PCR. Among 119 patients suspected of having meningitis, 43 had bacterial meningitis, 19 aseptic and one tuberculous; and there were 56 nonmeningitis cases (NMC). Presentation of four features at the same time-cerebrospinal fluid white blood cell count, protein, polymorphonuclear leukocytes and serum C-reactive protein-revealed 100% sensitivity and 86.4% specificity for diagnosis of bacterial meningitis. Haemophilus influenzae type b (60%), Streptococcus pneumoniae serotype 3 (28.5%) and Neisseria meningitidis B (63.5%) were the most prevalent serotypes. This study demonstrated that a well-designed combination of clinical and paraclinical features is useful, but these combinations are not good enough to be relied on as stand-alone exclusionary tests for the diagnosis of bacterial meningitis. In addition, public immunization of infants with the most prevalent bacterial meningitis serotypes is recommended.

Diagnostic accuracy of cerebrospinal fluid adenosine deaminase in detecting Tuberculous Meningitis

Objective

To determine diagnostic accuracy of Cerebro Spinal Fluid (CSF) Adenosine De-Aminase (ADA) in detecting Tuberculous Meningitis (TBM) keeping CSF Polymerase Chain Reaction (PCR) for Mycobacterium Deoxy Ribonucleic Acid (DNA) as gold standard.

Methods

This cross sectional validation study was conducted at Department of General Medicine of PNS Shifa Naval Hospital Karachi, Pakistan from Oct 2015 to Mar 2017 for a total duration of one and a half year. One hundred and thirty six patients were included. The diagnosis of TBM was based clinically on symptoms like fever, headache, altered mental state and signs of meningeal irritation with CSF findings of increased proteins, low glucose and lymphocytic pleocytosis. Lumbar puncture was done and approximately 4ml of CSF sample was withdrawn for analysis. Diagnosis of TBM was confirmed by doing CSF PCR test for mycobacterium tuberculosis DNA.

Results

Total 136 patients were enrolled in this study. Mean age in our study was 47.09±12.80 years, whereas frequency and percentages of male and female patients was 102 (75%) and 34 (25%) respectively. The diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value of CSF ADA level in detecting TBM was 71.32%, 84.21%, 95.45%, 98.97% and 53.85% respectively.

Conclusion

The study concludes that diagnostic accuracy of CSF ADA in detecting TBM is high which is proposed as an investigation to differentiate it from other causes of meningitis in places where PCR test is not available.

Miliary Tuberculosis Presenting With Meningitis in a Patient Treated With Mycophenolate for Lupus Nephritis: Challenges in Diagnosis and Review of the Literature

Tuberculosis is one of the top 10 causes of death worldwide according to the World Health Organization. Central nervous system involvement is usually the least common presentation of tuberculosis occurring in about 1% of all cases but yet can have very devastating outcomes. Lupus nephritis is one of the most common complications of systemic lupus erythematosus with up to two thirds of patients presenting with some degree of renal dysfunction. The mainstay of treatment is glucocorticoids; however, to sustain remission, steroid sparing agents such as cyclophosphamide, azathioprine and mycophenolate mofetil are used. Such patients, in addition to their baseline dysfunctional immune system, have a heightened risk of infections due to these drugs. In this article, we present a young woman who had recently been started on mycophenolate mofetil for control of class V lupus nephritis who presented with headaches, sinus pressure, and fevers. She had a protracted course of hospitalization as she failed to improve clinically and to respond to conventional therapy for acute bacterial sinusitis and meningitis. She was empirically started on antitubercular therapy 9 days after hospitalization. The diagnosis was not confirmed until day 18, the day results of cerebrospinal fluid acid-fast bacillus culture was reported. This case is reported to highlight the challenges in diagnosing Mycobacterium tuberculosis infection in an immunocompromised state and to demonstrate that its presentation can mimic numerous other conditions. Clinicians must maintain a high index of suspicion of Mycobacterium tuberculosis infection in such patients who present with nonspecific or unexplainable symptoms.

Determination and Validation of a Lower Cut Off Value of Cerebrospinal Fluid Adenosine Deaminase (CSF-ADA) Activity in Diagnosis of Tuberculous Meningitis

INTRODUCTION

Tuberculous meningitis is an infection of the meninges caused by Mycobacterium tuberculosis. It is one of the most common infectious diseases of the Central Nervous System (CNS) and a major health problem in developing countries like India. If there is delay in diagnosis and initiation of specific treatment, it causes significant morbidity and mortality. CSF-ADA 10 U/l is the standard cut off value that is used for differentiation between Tuberculous (TBM) and Non-Tuberculous Meningitis (non-TBM).

AIM

To determine and validate a lower cut off value for CSF-ADA for diagnosing TBM in an Indian setting.

MATERIALS AND METHODS

This was a prospective study involving 85 cases of meningitis whose CSF were analysed and ADA estimated using an enzymatic deamination assay kit. Diagnosis of various types of meningitis was made based on specified diagnostic criteria. The comparison of mean value of CSF- ADA activity of the two types of meningitis was done using two Sample t-test. A p-value of <0.05 was considered as significant. Cut off value to differentiate between TBM and non-TBM meningitis was determined using ROC curve analysis.

RESULTS

The CSF-ADA activity of TBM and non-TBM cases was compared. The mean CSF-ADA activity was found to be significantly higher in TBM patients (10.97±4.43; Mean±SD) than in non-TBM patients (5.09±1.53) which was statistically significant with a p-value of <0.001. A cut off value of 6.65 was calculated using ROC curve for the diagnosis of TBM which gave a sensitivity of 85.3% and a specificity of 84.3% for differentiating TBM from non-TBM. The positive predictive value was 78.3% and negative predictive value of 89.5% using the above cut off. The positive likelihood ratio was 5.44 and negative likelihood ratio of 0.17 when this lower cut off value was applied.

CONCLUSION

This study has demonstrated that CSF-ADA can be used as an important diagnostic tool in early diagnosis of TBM using a cut off value of 6.65. This cut off value gave a good sensitivity and specificity in differentiating it from non-TBM.