Biomedical subjects

Nicholas J Patronas

Publications and source records attributed to Nicholas J Patronas.

8 recordsLinked to original sources

PubMed2006

Diagnosis and treatment of vasculitis of the central nervous system in a patient with systemic lupus erythematosus.

BACKGROUND: A 23-year-old white woman with a 3-year history of systemic lupus erythematosus and a 15-month history of lupus nephritis and retinal vasculitis was successfully treated with antibiotics for Pseudomonas aeruginosa pneumonia while on moderate doses of corticosteroids. Even though her pneumonia had improved, she developed acute changes in her mental status that rapidly progressed to encephalopathy with coma. INVESTIGATIONS: Physical examination, fundoscopic examination, laboratory tests for metabolic abnormalities, cerebrospinal fluid analysis, microbiology and serologic testing, electroencephalogram, tests for IgM and IgG anticardiolipin antibodies, neuroimaging including CT of the brain and T1-weighted MRI before and after gadolinium contrast, and flow-attenuated inversion recovery MRI. DIAGNOSIS: Vasculitis of the central nervous system associated with systemic lupus erythematosus. MANAGEMENT: Intravenous methylprednisolone 1,000 mg/day for 3 days, one dose of intravenous pulse cyclophosphamide 750 mg/m(2), intravenous immunoglobulin 400 mg/kg/day for 4 days, plasmapheresis on alternate days for five cycles, and prednisone 40 mg/day. She continued monthly doses of intravenous pulse cyclophosphamide and intravenous pulse methylprednisolone for 6 months, followed by maintenance infusions every 3 months over 2 years. Prednisone was tapered over 18 months. Cyclophosphamide was discontinued after 2 years because of poor bone-marrow tolerance, and was replaced with mycophenolate mofetil 3,000 mg/ day and ciclosporin 50 mg twice daily.

Adult↗

PubMed2005

Lymphomatoid granulomatosis: abnormalities of the brain at MR imaging.

PURPOSE: To retrospectively evaluate the magnetic resonance (MR) imaging features of lymphomatoid granulomatosis in the brain. MATERIALS AND METHODS: The study, including retrospective analysis of data, was approved by the institutional review board of the National Cancer Institute and complied with Health Insurance Portability and Accountability Act. All patients gave written informed consent. Thirty-one patients with pathologically confirmed lymphomatoid granulomatosis were enrolled in a natural history and treatment study at the National Institutes of Health. Twenty-five patients (median age, 50 years; range, 18-62 years; 18 men, seven women) were evaluated with MR imaging of the brain at study entry for the presence of brain lesions and enhancing characteristics. Patients with abnormal findings were reexamined at intervals ranging from 2 to 19 months, as medically indicated. Cytologic analysis and flow cytometry of cerebrospinal fluid (CSF) were performed. Statistical analysis was performed to compare neurologic and CSF findings in patients with brain MR imaging abnormalities and in patients without abnormalities. The sensitivity of brain MR imaging was compared with that of CSF studies. RESULTS: Thirteen (52%) of 25 patients evaluated with MR imaging had a variety of brain abnormalities. Multiple focal intraparenchymal lesions, which exhibited T2 prolongation and commonly punctate or linear enhancement, were the most frequent abnormalities, and they were encountered in seven patients. The second most common finding was involvement of leptomeninges and cranial nerves, which manifested as abnormal enhancement on MR images obtained after contrast agent administration. This abnormality was seen in six patients. Involvement of dura mater was noted in another. Four patients had brain masses. Two had abnormal engorgement and intense enhancement of the choroid plexus. Most lesions resolved after treatment, but seven resulted in lacunar infarctions. Abnormal B cells were detected in the CSF with either cytologic techniques or flow cytometry in five patients. CONCLUSION: Lymphomatoid granulomatosis has a high rate of central nervous system involvement and a variable spectrum of lesions at MR imaging. Findings in this study suggest that MR imaging is more sensitive than CSF cytologic analysis or flow cytometry for detection of central nervous system involvement from lymphomatoid granulomatosis.

Adolescent↗

PubMed2004

Meningiomas may be a component tumor of multiple endocrine neoplasia type 1.

PURPOSE: Recently, an increased incidence of some nonendocrine tumors are reported in patients with multiple endocrine neoplasia type 1 (MEN 1). There are rare reports of meningiomas and other central nervous system tumors in these patients, but it is unknown if they are more frequent or if allelic loss of the MEN1 gene is important in their pathogenesis. The aim of this study was to address these two latter questions. EXPERIMENTAL DESIGN: Results from a prospective study of 74 MEN 1 patients with suspected/proven pancreatic endocrine tumors (PETs) were analyzed, as well as molecular studies performed on a resected meningioma. All patients had serial brain imaging studies (computed tomography, magnetic resonance imaging, and octreoscanning since 1994) and yearly studies evaluating MEN 1 involvement with a mean follow-up of 7.2 years. Results were compared with 185 patients with sporadic Zollinger-Ellison syndrome. RESULTS: Six patients (8%) had meningiomas. Meningiomas were single and found late in the MEN 1 course (mean age = 51 years). Magnetic resonance imaging/computed tomography were more sensitive than octreoscanning. Their diagnosis averaged 18 years after the onset of hyperparathyroidism, 10-15 years after pituitary disease or PETs. Meningiomas were 11 times more frequent in patients with PETs with MEN 1 than without MEN 1 (P = 0.017). No clinical, laboratory, or MEN 1 feature distinguished patients with meningiomas. Meningiomas were asymptomatic and 60% showed no growth. A resected meningioma showed loss of heterozygosity at 11q13 and 1p, including at p73 and ARHI/NOEY2 locus, but not at the neurofibromatosis 2 gene locus. CONCLUSIONS: These results show meningiomas are not an infrequent occurrence in MEN 1, and loss of the function of the MEN1 gene product plays a role in their pathogenesis in these patients.

Adult↗

PubMed2003

White matter lesions in Fabry disease occur in 'prior' selectively hypometabolic and hyperperfused brain regions.

Fabry disease is an X-linked disorder associated with early onset stroke. We previously found a significantly elevated cerebral blood flow (CBF) in patients with Fabry disease. We set to determine whether elevated resting CBF in Fabry disease is primarily a cerebrovascular abnormality or is secondary to enhanced neuronal metabolism. The relationship of cerebral metabolism and blood flow to Fabry leukoencephalopathy was also investigated. We measured the global and regional cerebral metabolic rate of glucose using 18-fluoro-deoxyglucose (FDG) and PET in 16 patients with Fabry disease (7 patients with leukoaraiotic lesions and 9 without) and in 7 control subjects. MRI fluid attenuated inversion recovery (FLAIR) studies were also performed in the patient and control groups. All control subjects had normal MRI FLAIR studies with no high-signal deep white matter lesions (WML). Patients were partitioned into FLAIR lesion and non-FLAIR lesion groups. We found no evidence of cerebral glucose hypermetabolism in Fabry disease. On the contrary, significantly decreased regional cerebral glucose metabolism (rCMRGlu) was found particularly in the deep white matter in the Fabry non-lesion group and exacerbated in the lesion group. Lesion-susceptible regions were relatively hyperperfused in non-lesion patients compared to the control group. We conclude that the elevated rCBF and decreased white matter rCMRGlu indicates a dissociation between metabolism and blood flow suggesting chronic deep white matter metabolic insufficiency.

Adult↗

PubMed2003

In-111 DTPA-octreotide scintigraphy for disease detection in metastatic thyroid cancer: comparison with F-18 FDG positron emission tomography and extensive conventional radiographic imaging.

PURPOSE: The utility of In-111 DTPA octreotide scintigraphy (SRS) for disease detection in patients with metastatic thyroid carcinoma (TCA) remains controversial. The authors compared the sensitivity of In-111-based SRS, F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET), and extensive conventional radiographic imaging (CRI) in this type of cancer. METHODS: SRS, FDG PET, and CRI were performed concurrently in 21 patients (age, 56.4 +/- 12.9 years) who had aggressive TCA. Concordance rates % of lesion positivity among pairs of different techniques (A and B) were calculated as the ratio of the number of lesions positive with both techniques divided by the sum of the total number of lesions positive with technique A + total number of lesions positive with technique B, which was then multiplied by 200. RESULTS: The combined use of CRI, FDG PET, and SRS resulted in the detection of 105 lesions, presumed to be due to metastatic deposits. Sensitivities for SRS and FDG-PET imaging were 49.5% and 67.6%, respectively. The lesion detection concordance rates were as follows: CRI versus FDG PET, 80.8%; CRI versus SRS, 74.2%; and FDG-PET versus SRS, 58.6%. Importantly, SRS detected five unexpected lesions, which were negative by both CRI and FDG-PET imaging. In two representative patients, a positive correlation (Spearman's rank = 0.71; = 0.0576) existed between the percentage of lesional In-111 DTPA octreotide uptake and the standard uptake value in eight concordant lesions. CONCLUSION: Although SRS has only moderate sensitivity for disease detection in metastatic TCA, sometimes it can reveal lesions that otherwise would be undetectable by either CRI or FDG-PET imaging.

Bone Neoplasms↗

PubMed2003

MR imaging features of thyrotropin-secreting pituitary adenomas at initial presentation.

OBJECTIVE: We report the MR imaging characteristics of thyrotropin-producing pituitary adenomas at their initial presentation and also report the role of MR imaging in predicting surgical outcome in these rare tumors. MATERIALS AND METHODS: We reviewed the records and MR images of 21 patients with thyrotropin-producing pituitary adenomas from 1984 to 1999. The imaging features of these tumors were examined, including enhancing characteristics and tumor volumes. A staging system of tumor invasion was designed by grading cavernous and sphenoid sinus invasion and suprasellar extension. A cumulative invasion score was then used as a predictor of short-term surgical outcome. RESULTS: Twenty patients had macroadenomas, and one patient had a microadenoma. In 17 of 21 patients, the thyrotropin-producing pituitary adenoma was clearly visualized as a hypoenhancing mass compressing the normal pituitary gland. Conversely, in four patients, the pituitary gland was not discernible because of complete distortion by the adenoma. Thyrotropin-producing pituitary adenomas were large and showed a tendency to invade surrounding structures. Tumor volume ranged from 0.42 to 94.2 cm(3) (mean +/- SD, 16.0 +/- 17.8 cm(3)). The mean score of tumor invasion was 4.77 +/- 2.06 of a maximal possible value of 9.0. A high staging score was found to be predictive of an unfavorable response to surgery. CONCLUSION: Thyrotropin-producing pituitary adenomas are usually large tumors at initial presentation with hypoenhancing features compared with normal pituitary tissue; they tend to be invasive. Greater amounts of invasion correlate with incomplete surgical removal of the tumor and continued hormonal secretion.

Adenoma↗

PubMed2002

Cerebrovascular disease in HIV-infected pediatric patients: neuroimaging findings.

OBJECTIVE: The goal of our study was to report on the prevalence and the neuroradiologic manifestations of cerebrovascular complications in children infected with HIV. We also elucidate the types of vascular involvement, identify their anatomic distribution, and discuss possible causes. MATERIALS AND METHODS: We conducted a retrospective study of 567 patients (age range, 1 month-29 years; median age, 5.47 years) who acquired HIV as children. Of these, 426 patients (75%) were evaluated with neuroimaging studies. We reviewed these studies to identify the cerebrovascular abnormalities and classify them by type, anatomic location, and shape. RESULTS: Eleven children (2.6%) were found to have cerebrovascular lesions. Only one had focal neurologic symptoms at the time of diagnosis. Twenty-six aneurysms were found in seven patients, and 27 infarctions were found in eight patients. In four of the patients with infarctions, fusiform aneurysms of the cerebral arteries were also identified. Most patients had advanced HIV disease. Nine of the 11 patients were infected by a vertical transmission route or during blood transfusion early in the neonatal period. In this group of patients, the diagnosis of cerebrovascular disease was made earlier (mean age at diagnosis, 8.2 years) than in the two patients who were infected later in life (mean age at diagnosis, 14.9 years). CONCLUSION: HIV-infected children have an increased incidence of cerebrovascular disease that is associated with severe immune suppression and with vertically acquired HIV infection or exposure to the virus in the neonatal period. Despite extensive lesions, most children in our study were asymptomatic. Screening with MR imaging should be considered for high-risk children and is advisable when evidence of neurologic symptoms or neurocognitive dysfunction is noted.

AIDS Arteritis, Central Nervous System↗

PubMed2002

Quantification of brain lesions using interactive automated software.

We developed an interactive program, Analysis of Brain Lesions (ABLe) so that researchers studying the effects of brain lesions on cognition could have a user-friendly tool that could quantitatively characterize such lesions. The program was prepared in Tcl/Tk and will run on any UNIX or PC LINUX platform with the MEDx medical imaging software package. The ABLe is almost completely automated and determines the brain lesion size as well as which cytoarchitectonic brain regions (Brodmann areas) are contained within the boundaries of the lesion. Lesion data from multiple subjects can be grouped together and the degree of lesion overlap displayed. All images are analyzed and displayed within standard Talairach coordinate space, and the precision of the match between the ABLe Brodmann area graphics and the subject/patient brain is easily confirmed. The program is the first easy-to-use software that contains these specific features and is available for interested researchers with a background in lesion analysis.

Adult↗