Chronic Meningitis

Entzündliche Erkrankungen

Unter einer Meningitis versteht man eine Entzündung von Pia mater und Arachnoidea. Das Erregerspektrum ist weit und reicht von Bakterien, die hämatogen-metastatisch, fortgeleitet oder durch offene Hirnverletzung zur eitrigen Meningitis führen, über Viren zu Pilzen und Parasiten. Insbesondere bei den unbehandelt häufig letal verlaufenden eitrigen Meningitiden ist eine rasche Diagnose mit Erregernachweis notwendig. Unverzüglich ist daraufhin eine spezifische, der regionalen Resistenzentwicklung angepasste Therapie einzuleiten. Die meningeale Affektion im Rahmen einer Listeriose oder Tuberkulose verdient aufgrund des klinischen Bildes, des Verlaufs und der spezifischen Therapie besondere Beachtung. Die fungalen Infektionen werden, da klinisch häufig als Meningoenzephalitis imponierend, in Abschn. 33.3 abgehandelt.

Chronic Meningitis in Thailand

The charts of 114 consecutive patients with chronic meningitis admitted to a general hospital in Bangkok, Thailand, between 1993 and 1999 were retrospectively reviewed. The most common causative agents were Cryptococcus neoformans (54%) and Mycobacterium tuberculosis (37%). HIV and other underlying diseases had a major impact on the presentation of chronic cryptococcal meningitis patients. Compared to HIV-negative cryptococcal meningitis patients (21%), HIV-positives (79%) had a significantly lower incidence of focal signs (p = 0.02), hydrocephalus (p = 0.03) and seizures (p = 0.001) during hospital stay, furthermore, a lower leucocyte level, a significantly higher glucose level (p = 0.02) and a lower protein level (p = 0.03) in the first cerebrospinal fluid examination. Of the 43 patients with chronic tuberculous meningitis, only 3 were HIV positive. Focal neurologic deficits were found more frequently in tuberculous meningitis patients (p = 0.001) when compared to cryptococcal meningitis patients without HIV. Cerebral infarction on cerebral CT was indicative of tuberculous meningitis. Cryptococcal meningitis patients with HIV infection had a worse outcome compared to non-AIDS patients. Advanced stage of the disease on admission, decreased level of consciousness prior to and on the admission day and raised intracranial pressure above 40 cm H(2)O at any given time were predictive of a poor outcome in tuberculous meningitis patients.

Chronic meningitis

Chronic meningitis is a clinical syndrome that is characterized by persistent or progressive signs and symptoms of meningitis associated with cerebrospinal fluid pleocytosis and elevated protein concentrations, lasting for a duration of at least 4 weeks without improvement. A large number of infectious and noninfectious diseases, many of which are difficult to diagnose, can cause chronic meningitis. Careful attention to exposure and travel history, physical examination findings, and certain patterns of CSF parameters, coupled with other specific laboratory evaluations, all play important roles in trying to identify the etiologic agent causing the chronic meningitis.

Outcome of chronic idiopathic meningitis

OBJECTIVE

To record long-term follow-up data on patients with chronic idiopathic meningitis.

DESIGN

We retrospectively reviewed the outcome of 49 patients who were examined at the Mayo Clinic between 1978 and 1990.

MATERIAL AND METHODS

For all patients, symptoms, signs, laboratory values, results of imaging studies, findings on biopsies, results of any empiric treatment, and results of autopsy, if applicable, were assessed. Some of these findings were stratified on the basis of good versus poor outcome of the patients and were analyzed statistically.

RESULTS

Of the 49 patients who fulfilled the criteria for chronic idiopathic meningitis, 10 had a cause identified after repeated studies, brain biopsy, or autopsy (8 of these had a neoplasm). Of 21 brain biopsies, 5(24%) yielded a diagnosis. Follow-up of the 39 undiagnosed cases showed that 33 (85%) had a good outcome despite an often prolonged illness. Two patients (5%) died of the meningeal process. Of the eight patients treated empirically with antituberculous medications, none responded. Corticosteroid therapy was effective in 52% of the patients thus treated, but it did not influence the outcome.

CONCLUSION

In this study, 85% of undiagnosed cases of chronic meningitis were benign. No clinical or laboratory findings predicted those patients who had a fatal outcome. In our study population, the most useful empiric therapy was corticosteroids rather than antituberculous medications.

Chronic meningitis: the role of meningeal or cortical biopsy

Meningeal and cortical biopsies were evaluated in 37 patients (25 men and 12 women; mean age, 54 yr) who had chronic meningitis of an unknown cause between 1985 and 1993 (the era of magnetic resonance imaging). Magnetic resonance imaging with gadolinium contrast was the most useful diagnostic imaging technique, demonstrating meningeal enhancement in 15 of 32 patients (47%). Only 2 of 32 (6%) computed tomographic scans revealed enhancement. A definitive diagnosis was made in 16 of 41 biopsies (39%), but in cases where enhancement was present on either magnetic resonance imaging or computed tomography, a diagnosis was obtained in 80% (12 of 15 cases). Only 2 of 22 biopsies (9%) from nonenhancing regions were diagnostic. Although the locations of enhancement were distributed evenly, biopsies through suboccipital and pterional craniotomies gave the highest diagnostic yields (50%). Furthermore, if the biopsies were obtained from enhancing regions, the yield of these two approaches increased to 84 and 100%, respectively. Of 18 cases in which biopsy samples were taken from both the meninges and cortex, only 1 had cortical involvement alone. The meninges were therefore diagnostic in 15 of the 16 definitive diagnostic cases (94%). Second biopsies were necessary in four cases, of which the three biopsies from enhancing regions were diagnostic. The most frequent causes of chronic meningitis were sarcoid (31%) and metastatic adenocarcinoma (25%).(ABSTRACT TRUNCATED AT 250 WORDS)

Primary diffuse leptomeningeal gliomatosis (PDLG): a neoplastic cause of chronic meningitis

Cancerous 'chronic meningitis' may be related to subarachnoid space involvement by solid tumors, hematologic malignancies or rarely intraparenchymatous gliomas. Primary leptomeningeal gliomatosis is a rare condition that is attributed to malignant transformation of heterotopic neuroglial tissue. We discuss the clinical and biological features of a patient who died with the diffuse form of primary leptomeningeal gliomatosis (PDLG). A literature search shows that a one to two months long non-specific prodromal phase followed by a fluctuating neurologic downhill course is suggestive of this disease. Cerebro-spinal fluid (CSF) cytology has been diagnostic in only 1 of 8 reported cases. Recent technical progress, including the use of GFAP (glial fibrillary acidic protein) directed antibody, may enhance the sensitivity of CSF cytologies. Diagnosis may require repeated cerebral biopsies, because the hemispheric lesions are often separated by normal tissue. PDLG must be added to the large differential diagnosis of 'chronic meningitis'.

Infections of the central nervous system

Infections of the central nervous system are common, serious medical conditions. One hundred consecutive adult cases with purulent meningitis of known etiology encountered by the Medical Service at Parkland Memorial Hospital were reviewed. Streptococcus pneumoniae was the most common pathogen (56 cases), followed by Neisseria meningitidis (16 cases) and Listeria monocytogenes (seven cases). Hemophilus influenzae, Staphylococcus aureus, and streptococci each accounted for five cases. An additional 15 patients had purulent meningitis with a pathogen being isolated. Twenty five purulent meningitis cases of known etiology after trauma or neurosurgery were reviewed. Staphylococcus aureus (five cases), Staphylococcus epidermidis (four cases), and gram negative bacilli (14 cases) were the most common pathogens. Review of intracranial suppurative infections demonstrated advances in microbiology, antibiotic therapy, and imaging, leading to improvements in therapy. Subdural empyema continues to be a difficult diagnosis to make and apparently is related to the anatomic pathology of the infectious process. To illustrate salient features about granulomatous meningitis and encephalitis, cases of tuberculous meningitis, herpes simplex encephalitis, St. Louis encephalitis, and encephalitis of undetermined etiology are presented and discussed.

Drug-induced aseptic meningitis. Diagnosis leads to quick resolution

Drug-induced aseptic meningitis is a syndrome that should be considered in the differential diagnosis of acute and recurrent aseptic meningitis. It has been observed in all age-groups and can occur following the use of a wide spectrum of pharmaceutical agents. Presumptive diagnosis is made by demonstrating the resolution of symptoms after drug withdrawal, and definitive diagnosis is made by conducting a drug rechallenge. Fortunately, the syndrome is usually benign and resolves quickly following drug cessation.

Antibiotic treatment of community acquired bacterial meningitis

Community acquired meningitis is predominantly caused by three agents: Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis Four physical properties of available drugs--molecular size, protein binding, lipid solubility and ionization--affect drug entry to the central nervous system (CNS). These factors, coupled with acute changes in blood-brain barriers and intrinsic bactericidal activity, have a bearing on the success of treatment with all agents. Third generation cephalosporins have largely supplanted older regimens due to their intrinsic qualities of greater bactericidal activity, optimal cerebrospinal fluid pharmacokinetics, and low toxicity. The pharmacological principles of treatment of CNS bacterial infections, pharmacology of available drugs, and current treatment recommendations are reviewed.

Spinal arachnoiditis with Cryptococcus neoformans in a nonimmunocompromised child

Cryptococcal spinal arachnoiditis occurs in patients with meningitis and usually when they are immunocompromised. It is rare in children. We report a child without evidence of immunologic abnormality who developed paraparesis due to a primary cryptococcal arachnoiditis without meningitis and who improved with adequate therapy.

Intracranial nonspecific inflammatory granuloma

A case of nonspecific inflammatory granuloma arising from the dura mater near the hypoglossal canal is reported. A 38-year-old woman developed an isolated left hypoglossal nerve palsy. Computed tomography and magnetic resonance imaging demonstrated an enhanced tumorous lesion at the inner orifice of the left hypoglossal canal. Skull x-ray was normal, and cerebral angiography showed no vascular abnormalities. Examination of the cerebrospinal fluid showed mild pleocytosis with a predominance of lymphocytes. Systemic examination revealed no abnormalities. The tumor was removed completely and pathologic investigation revealed that it was an inflammatory granuloma. The patient's history and laboratory data, however, failed to suggest the underlying disease, and histopathologic examination did not indicate any special type of granuloma. Therefore, the lesion was diagnosed as a nonspecific inflammatory granuloma.

Leptomeningeal cancer in leukemia and solid tumors

Although some patients with overt leptomeningeal cancer can now be cured, the proportion of patients who survive is very small, and the cost of cure, in terms of neuropsychological and educational morbidity, is substantial. Yet the incidence of central nervous system infiltration of systemic cancer is generally increasing, in most instances because control of systemic cancer has sufficiently prolonged survival to permit leptomeningeal metastases to develop and become symptomatic or detectable. The best chance for prolongation of life and possible cure is early detection and aggressive therapy in those forms of cancer that are amenable to therapy. We review the incidence of the various forms of leptomeningeal metastases, current concepts of pathogenesis and pathophysiology, clinical and laboratory features of leptomeningeal cancer, the available therapies, and the associated toxicities. The various methods that have been used to prevent and treat leptomeningeal cancer are described with an emphasis on childhood acute lymphoblastic leukemia (ALL) because it plays a predominant role in our understanding of meningeal neoplasms in general.