Diagnosis Of Focal Brain Lesions Research Articles

Diagnostic accuracy of magnetic resonance spectroscopy (MRS) for diagnosis of focal brain lesions taking histopathology as gold standard.

Objective: To determine diagnostic accuracy of MRS for diagnosis of malignant brain lesions taking histopathology as gold standard. Study Design: Cross Sectional Validation study. Setting: Department of Radiology, Lahore General Hospital, Lahore. Material & Methods: A total number of 127 patients who were referred for the diagnosis of focal brain lesions were included. In all patients, MRS was done by consultant radiologist to diagnose malignancy. All patients underwent surgery in the neurosurgery department and after surgery biopsy specimen were taken for diagnosis of malignancy using histopathology findings. Results: Mean age of patients was 40.88±11.37 years. There were 88 (69.29%) males and 39 (30.71%) female patients. On MRS, malignancy was diagnosed in 99 (77.95%) patients and on histopathology malignancy was diagnosed in 102 (80.31%) patients. Regarding diagnostic accuracy, MRS was 97.00% sensitive, 94.10% specific, with PPV of 78.60% and NPV of 88.00%. Conclusion: Magnetic resonance spectroscopy (MRS) has good sensitivity and specificity in differentiating neoplasm from non-neoplastic focal brain lesions.

Problems of differential diagnosis of focal brain lesions in patients with HIV infection

Currently, the leading cause of social disadaptations and disability of patients at advanced stages of HIV infection, as well as adverse outcomes, is the presence of severe comorbid variants of the course of HIV infection: HIV and co-infection of chronic viral hepatitis, tuberculosis, HIV and malignant tumors, and HIV-associated neurological diseases. In pediatric practice, the combination of HIV-induced and perinatal CNS lesions is the most relevant. The differential diagnosis of these conditions is complicated due to the polymorphism of clinical manifestations and the possibility of combining several pathological conditions simultaneously in patients. Neuroimaging data does not always have clear criteria for determining the exact cause of cerebral damage. The article presents data of own clinical neuroimaging observations of two patients with perinatal and parenteral HIV infection. The nervous system damage was polyetiological in nature and was presented in one case by a combination of HIV-encephalitis, cerebral toxoplasmosis and CNS lymphoma, in the second by the presence of Bourneville-Pringle disease (tuberous sclerosis) with the formation of giant-cell astrocytoma and HIV-induced brain damage. It should be noted that the optimization of the antiretroviral therapy regimen in the case of a combination of B-cell lymphoma and cerebral toxoplasmosis in a child with perinatal HIV infection led to clinical and laboratory remission

IgG4 specific to Toxoplasma gondii excretory/secretory antigens in serum and/or cerebrospinal fluid support the cerebral toxoplasmosis diagnosis in HIV-infected patients

Cerebral toxoplasmosis is the most common neurological opportunistic disease manifested in HIV infected patients. Excretory/secretory antigens (ESA) are serological markers for the diagnosis of reactivation of the infection in HIV-infected patients with cerebral toxoplasmosis. Immunosuppressed patients develop high antibody titers for ESA. However, little is known about the humoral response for these antigens. The present study analyzed the profile of antibody recognition against ESA in comparison with tachyzoite lysate antigen (TLA) in 265 sera and 270 cerebrospinal fluid (CSF) samples from infected patients with Toxoplasma gondii and or HIV and in sera of 50 healthy individuals. The samples of sera and CSF were organized in 8 groups. The sera sample groups were: Group I — Se/CT/AIDS (patients with cerebral toxoplasmosis/AIDS) with 58 samples; Group II — Se/ONinf/AIDS/PosT (patients with AIDS/other neuroinfections/positive toxoplasmosis) with 49 samples; Group III — Se/ONinf/AIDS/NegT (patients with AIDS/other neuroinfections/negative toxoplasmosis) with 58 samples; Group IV — Se/PosT/NegHIV (individuals with asymptomatic toxoplasmosis/negative HIV) with 50 samples and Group V — Se/NegT/NegHIV (healthy individuals/negative toxoplasmosis and HIV) with 50 samples. The CSF sample groups were: Group VI — CSF/CT/AIDS (patients with cerebral toxoplasmosis/AIDS) with 99 samples; Group VII — CSF/ONinf/AIDS/PosT (patients with AIDS/other neuroinfections/positive toxoplasmosis) with 112 samples, and Group VIII — CSF/ONinf/AIDS/NegT (patients with AIDS/other neuroinfections/negative toxoplasmosis) with 59 samples. Levels of IgM, IgA, IgE, IgG and subclasses were determined by ELISA against TLA and ESA antigens. IgM, IgA or IgE antibodies against ESA or TLA were not detected in sera from patients with toxoplasmosis suggesting that all patients were in chronic phase of the infection. High levels of IgG1 against TLA were found in sera samples from groups I, II and IV and in CSF samples from groups VI and VII; whereas IgG2, IgG3 and IgG4 levels were not detected in the same sera or CSF sample groups. However, patients from groups I and VI, that had tachyzoites circulating in blood and CSF respectively, produced a mix of IgG1 and IgG4 antibodies against ESA. IgG2 against ESA were predominant in serum from patients with the latent (non-active) T. gondii infection/HIV negative and in CSF samples from patients with other neuroinfections and positive toxoplasmosis (groups IV and VII, respectively). IgG4 levels against ESA were found to be significantly (P<0.05 and P<0.005) higher in patients with cerebral toxoplasmosis (groups I and VI, respectively) in comparison with groups II, IV and VII. This data suggest that IgG4 can be valuable for supporting the diagnosis of focal brain lesions, caused by T. gondii infection, in HIV-infected patients. This approach might be useful, mainly when molecular investigation to detect parasites is not available.

CXCL13 plus interleukin 10 is highly specific for the diagnosis of CNS lymphoma

AbstractEstablishing the diagnosis of focal brain lesions in patients with unexplained neurologic symptoms represents a challenge. The goal of this study is to provide evidence supporting functional roles for CXC chemokine ligand (CXCL)13 and interleukin (IL)-10 in central nervous system (CNS) lymphomas and to evaluate the utility of each as prognostic and diagnostic biomarkers. We demonstrate for the first time that elevated CXCL13 concentration in cerebrospinal fluid (CSF) is prognostic and that CXCL13 and CXCL12 mediate chemotaxis of lymphoma cells isolated from CNS lymphoma lesions. Expression of the activated form of Janus kinase 1 supported a role for IL-10 in prosurvival signaling. We determined the concentration of CXCL13 and IL-10 in CSF of CNS lymphoma patients and control cohorts including inflammatory and degenerative neurologic disease in a multicenter study involving 220 patients. Bivariate elevated CXCL13 plus IL-10 was 99.3% specific for primary and secondary CNS lymphoma, with sensitivity significantly greater than reference standard CSF tests. These results identify CXCL13 and IL-10 as potentially important biomarkers of CNS lymphoma that merit further evaluation and support incorporation of CXCL13 and IL-10 into diagnostic algorithms for the workup of focal brain lesions in which lymphoma is a consideration.

Detection of Toxoplasma gondii, Epstein-Barr Virus, and JC Virus DNAs in the Cerebrospinal Fluid in Acquired Immunodeficiency Syndrome Patients with Focal Central Nervous System Comlications.

Toxoplasmic encephalitis (TE), primary central nervous system lymphoma (PCNSL) and progressive multifocal leukoencephalopathy (PML) are major central nervous system (CNS) diseases in patients with acquired immunodeficiency syndrome (AIDS). We assessed the diagnostic value of polymerase chain reaction (PCR) in the detection of DNAs of Toxoplasma gondii (T. gondii), Epstein-Barr virus (EBV) and JC virus (JCV) in the cerebrospinal fluid (CSF). We compared the PCR results with those of pathological findings at autopsy. The present study included 23 autopsies representing those in whom CSF samples were obtained before death while the patient was hospitalized or at autopsy. The threshold levels for PCR detection were 4 tachyzoites of T. gondii, 5-15 genomes of EBV and 10 genomes of JCV. We identified T. gondii DNA in 4 out of 5 autopsy-defined cases of TE, EBV DNA in 5 out of 5 cases with PCNSL, and JCV DNA in 2 out of 2 cases with PML. The specificity of PCR was 100% in TE, 78% in PCNSL, and 100% in PML. Although the number of cases was relatively small in this study, PCR correctly identified T. gondii DNA in those cases in which PML or PCNSL was the sole clinical diagnosis. Our results indicate that PCR examination of CSF is a clinically useful tool for the diagnosis of focal brain lesions in patients with AIDS.

Management of intracerebral lesions in patients with HIV: a retrospective study with discussion of diagnostic problems.

A total of 95 patients who presented in 1994 and 1995 with focal brain lesions at a London HIV centre were studied retrospectively. Patients were allocated to "definite" or "presumed" diagnostic categories of toxoplasma encephalitis (TE), primary CNS lymphoma (PCNSL) or progressive multifocal leukoencephalopathy (PML), based on strict criteria. The number in each category was: TE, 20; PCNSL, 9; PML, 7; presumed TE, 12; presumed PCNSL, 8 and presumed PML, 17. There were 20 patients in whom a diagnosis could not be made, and there were three non-HIV diagnoses. Demographic data, features at presentation and routine CSF analysis were not discriminatory in making a diagnosis. Toxoplasma titres were a median of 1:256 in those with TE compared to 1:16 in all other groups (p < 0.001) and those with TE were less likely to be on toxoplasma prophylaxis compared to those with PCNSL (p < 0.002). Survival with TE (median of 446 days) was significantly longer than survival in all other groups. Survival with either confirmed or presumed PML was similar. The problems of diagnosis of focal brain lesions in HIV patients are discussed and a management flow chart for mass lesions is proposed.

High dosage administration of paramagnetic contrast media in diagnosis of focal brain lesions

In analogy with high-dose contrast-enhanced CT, there have been a few studies during recent years that have dealt with high-dose paramagnetic contrast dyes in MRI. One reason for these studies was the development of new and low-osmolar contrast agents in the MR field. Depending on the clinical problem, a high-dose contrast study in MRI is rarely indicated: (1) in metastatic disease, MR imaging with high-dose contrast material is indicated when the standard dose study is negative or only shows a solitary cerebral lesion or a number of lesions just suitable for radiosurgery; (2) in patients with malignant glioma the high-dose study allows better definition of the tumor margins. If a radical surgical approach is planned, the diagnostic potential should be fully used; if only a biopsy or subtotal debulking is planned, a standard dose study is enough. (3) in patients with MS, a high-dose study is only recommended within therapeutic trials in which the number of active plaques is a primary variable.