Prognosis in meningoencephalitis of unknown origin in dogs: Risk factors associated with survival, clinical relapse, and long-term disability

BACKGROUND

Meningoencephalitis of unknown origin (MUO) comprises a group of noninfectious inflammatory diseases affecting the central nervous system of dogs. Previous studies have reported individual risk factors for survival but prognostication for MUO remains challenging.

OBJECTIVES

Identify clinical prognostic variables in dogs with MUO.

ANIMALS

A retrospective study of 447 dogs presented to 2 UK referral hospitals and diagnosed with MUO.

METHODS

Medical records of dogs diagnosed with MUO were retrospectively reviewed. Multivariable logistic regression was used for the identification of risk factors for survival and Cox proportional hazards analysis for the identification of risk factors for clinical relapse.

RESULTS

Eighty-two percent (366/447) of dogs with presumptive MUO survived to discharge and 63.5% (284/447) were alive at 6 months; 36% of the latter (103/284) had persistent neurological deficits. Breed (pugs; P = .03), epileptic seizures (P < .001), paresis (P < .001), and higher neurodisability scale (NDS) score (P < .001) at presentation were negatively associated with survival to 6 months. Dogs with persistent deficits had higher NDS scores on presentation (P = .001). Median follow-up time was 11 months (interquartile range [IQR], 1-24) and 50.6% (160/316) relapsed during treatment (median time to relapse, 7 months; IQR, 2-15). Incomplete resolution of the clinical signs during the 6 months after diagnosis (P < .001), higher NDS score (P < .001), and longer duration of the clinical signs (P < .001) were associated with relapse.

CONCLUSIONS AND CLINICAL IMPORTANCE

Knowledge of risk factors associated with survival, incomplete recovery and clinical relapse in MUO can help guide monitoring and treatment and improve owner communications regarding prognosis for this debilitating disease.

Cryptococcal meningoencephalitis: time for action

Cryptococcal meningoencephalitis was first described over a century ago. This fungal infection is preventable and treatable yet continues to be associated with excessive morbidity and mortality. The largest burden of disease resides in people living with HIV in low-income and middle-income countries. In this group, mortality with the best antifungal induction regimen (7 days of amphotericin B deoxycholate [1·0 mg/kg per day] and flucytosine [100·0 mg/kg per day]) in a clinical trial setting was 24% at 10 weeks. The world is now at an inflection point in terms of recognition, research, and action to address the burden of morbidity and mortality from cryptococcal meningoencephalitis. However, the scope of interventional programmes needs to increase, with particular attention to implementation science that is specific to individual countries. This Review summarises causes of excessive mortality, interventions with proven survival benefit, and gaps in knowledge and practice that contribute to the ongoing high death toll from cryptococcal meningoencephalitis. TRANSLATIONS: For the Vietnamese and Chichewa translations of the abstract see Supplementary Materials section.

Rickettsia felis identified in two fatal cases of acute meningoencephalitis

BACKGROUND

Rickettsia felis has recently emerged worldwide as a cause of human illness. Typically causing mild, undifferentiated fever, it has been implicated in several cases of non-fatal neurological disease in Mexico and Sweden. Its distribution and pathogenicity in Southeast Asia is poorly understood.

METHODOLOGY/PRINCIPAL FINDINGS

We retroactively tested cerebrospinal fluid (CSF) or sera from 64 adult patients admitted to hospital in North Sulawesi, Indonesia with acute neurological disease. Rickettsia felis DNA was identified in the CSF of two fatal cases of meningoencephalitis using multi-locus sequence typing semi-nested PCR followed by Sanger sequencing. DNA from both cases had 100% sequence homologies to the R. felis reference strain URRWXCal2 for the 17-kDa and ompB genes, and 99.91% to gltA.

CONCLUSION/SIGNIFICANCE

The identification of R. felis in the CSF of two fatal cases of meningoencephalitis in Indonesia suggests the distribution and pathogenicity of this emerging vector-borne bacteria might be greater than generally recognized. Typically Rickettsia are susceptible to the tetracyclines and greater knowledge of R. felis endemicity in Indonesia should lead to better management of some acute neurological cases.

Neurological symptoms and mortality associated with Streptococcus gallolyticus subsp. pasteurianus in calves

Suppurative meningitis-meningoencephalitis (M-ME) is a sporadic disease in neonatal ungulates and only a few studies have reported the involvement of Streptococcus bovis/Streptococcus equinus complex (SBSEC) members in bovine neonatal M-ME. The SBSEC taxonomy was recent revised and previous biotype II/2 was reclassified as S. gallolyticus subsp. pasteurianus (SGP). The aim of this study was to describe a case of fatal neonatal neurological syndrome associated with SGP in calves. Ten calves were monitored because of neurological hyperacute symptoms associate with bilateral hypopyon and death. They were not fed with maternal colostrum; two of them died and were subjected to bacteriological, histopathological and biomolecular analysis as well as antibiotic susceptibility test. Both animals presented lesions mostly concentrated to meninges and brain and had bilateral hypopyon. Nine strains isolated in purity from brain, ocular humors and colon were identified as S. bovis group by using the API Strep system and as S. gallolyticus by using the 16S rRNA sequence. Two of these strains where subjected to WGS analysis that confirmed the sub-species identification and the clonality of the two SGP strains. The strains were found resistant to OT, SXT, MTZ and EN and susceptible to AMP, AMC, KZ and CN. We hypothesized that the syndrome observed could be due to the lack of maternal colostrum feeding. A timely and precise diagnosis could have likely prevented the death of the calves and, since the zoonotic potential of SBSECs members is known, accurate and rapid identification is required.

[Acute care of patients with bacterial meningitis]

BACKGROUND

Bacterial meningitis is a life-threatening emergency that is still associated with high mortality and poor outcome.

OBJECTIVE

The purpose of this article is to provide a review of clinical presentation, diagnostic procedure, therapy, and prognosis in bacterial meningitis. Prognostic factors which could be influenced positively are identified and a focused procedure in the emergency setting and for the treatment of complications are provided.

MATERIAL AND METHODS

This work is based on a literature search (PubMed, guidelines) and personal experience (standard operating procedures, SOP).

RESULTS

Despite improved health care, bacterial meningitis is still associated with high mortality and poor neurological outcome, which has remained largely unaltered during recent decades. Diagnosis and, more importantly, effective therapy of bacterial meningitis are often delayed, having an immediate negative influence on clinical outcome. Neurological and nonneurological complications often necessitate intensive care and may occur rapidly or in the further course of the disease.

CONCLUSION

Immediate initiation of effective therapy is crucial to positively influence mortality and neurological outcome. Antibiotics should be administered within 30 min after admission. To achieve this, a focused and well-organized procedure in the emergency setting is necessary. Because of intra- and extracranial complications, patients need to be treated on intensive care units including neurological expertise and interdisciplinary support.

Cryptococcus neoformans hyperfilamentous strain is hypervirulent in a murine model of cryptococcal meningoencephalitis

Cryptococcus neoformans is a human fungal pathogen that causes lethal infections of the lung and central nervous system in immunocompromised individuals. C. neoformans has a defined bipolar sexual life cycle with a and α mating types. During the sexual cycle, which can occur between cells of opposite mating types (bisexual reproduction) or cells of one mating type (unisexual reproduction), a dimorphic transition from yeast to hyphal growth occurs. Hyphal development and meiosis generate abundant spores that, following inhalation, penetrate deep into the lung to enter the alveoli, germinate, and establish a pulmonary infection growing as budding yeast cells. Unisexual reproduction has been directly observed only in the Cryptococcus var. neoformans (serotype D) lineage under laboratory conditions. However, hyphal development has been previously associated with reduced virulence and the serotype D lineage exhibits limited pathogenicity in the murine model. In this study we show that the serotype D hyperfilamentous strain XL280α is hypervirulent in an animal model. It can grow inside the lung of the host, establish a pulmonary infection, and then disseminate to the brain to cause cryptococcal meningoencephalitis. Surprisingly, this hyperfilamentous strain triggers an immune response polarized towards Th2-type immunity, which is usually observed in the highly virulent sibling species C. gattii, responsible for the Pacific Northwest outbreak. These studies provide a technological advance that will facilitate analysis of virulence genes and attributes in C. neoformans var. neoformans, and reveal the virulence potential of serotype D as broader and more dynamic than previously appreciated.

Clinical characteristics and outcomes of patients with cryptococcal meningoencephalitis in a resource-limited setting

BACKGROUND

Cryptococcosis is a potentially lethal opportunistic infection among human immunodeficiency virus (HIV)-infected individuals. The mortality rate of patient with cryptococcal meningoencephalitis (CM) in Thailand is high. Studying the factors associated with treatment failure is important to improve outcome.

MATERIAL AND METHOD

A retrospective study of patients with cryptococcosis in Siriraj Hospital, Thailand, during 2005-2008 was conducted. Treatment options, outcomes, survival and factors associated with outcomes and mortality were analyzed.

RESULTS

A total of 143 patients with cryptococcosis were enrolled. Mean age was 39 years old and 58.7% were male. There were 124 HIV-infected patients (86.7%) and 116 of those had CM. Favorable clinical response in HIV-associated CM was 55.2% and 6-month survival was 67.2%. Relapse was found in 21 patients (18.1%). Factors associated with favorable clinical response included lower opening and closing pressures and a higher white blood cell in cerebrospinal fluid (CSF). Favorable mycological response was 56.8% and factors associated with favorable mycological response were a lower CD4+ T-lymphocyte count and a longer amphotericin B treatment. The median time to achieve CSF sterilization was 30 days. Factors associated with survival were a longer course of amphotericin B, a lower CSF opening pressure and a higher white blood cell in CSF.

CONCLUSION

High mortality rate of HIV-associated CM was demonstrated and most likely linked to inadequate induction antifungal therapy resulting in inability to sterilize CSF. New strategies and/or guidelines are suggested to improve survival.

Balamuthia mandrillaris meningoencephalitis associated with solid organ transplantation--review of cases

We report the first identified transmission of Balamuthia mandrillaris through solid organ transplantation. Kidneys were transplanted from a donor with presumptive diagnosis of autoimmune encephalitis. Shortly after, the recipients developed neurologic symptoms. Magnetic Resonance Imaging of the brain from the donor and both kidney recipients demonstrated multiple ring enhancing lesions with surrounding edema and adjacent leptomeningeal extension. In addition most of the lesions demonstrated signal changes suggesting central hemorrhagic foci. Specimens were tested locally and at the Centers for Disease Control and Prevention. Histopathology revealed B. mandrillaris in either brain tissue and/or cerebral spinal fluid in the donor and recipients.

[The tuberculous meningoencephalitis in patients with later stages of HIV infection]

Based on the examination and treatment of 120 patients with tuberculous meningoencephalitis (TM) in the later stages of HIV infection, the differences between these patients and patients without HIV infection were found. HIV-infected patients with TM had a more acute disease onset, more clinical symptoms of encephalitis confirmed by magnetic resonance imaging of the brain, more frequent presence of mycobacterium tuberculosis in the cerebrospinal fluid and higher level of resistance to tuberculosis drugs. The morphologic study demonstrated the domination of necrotic and exudative reactions over productive inflammation with destructive abscess-type lesions in the brain matter. The mortality was more than 2 times higher than that in the control group.

Treatment and prophylaxis of invasive candidiasis

Invasive candidiasis (IC) is a leading cause of morbidity and mortality in preterm infants. Even if successfully treated, IC can cause significant neurodevelopmental impairment. Preterm infants are at increased risk for hematogenous Candida meningoencephalitis owing to increased permeability of the blood-brain barrier, so antifungal treatment should have adequate central nervous system penetration. Amphotericin B deoxycholate, lipid preparations of amphotericin B, fluconazole, and micafungin are first-line treatments of IC. Fluconazole prophylaxis reduces the incidence of IC in extremely premature infants, but its safety has not been established for this indication, and as yet, the product has not been shown to reduce mortality in neonates. Targeted prophylaxis may have a role in reducing the burden of disease in this vulnerable population.

[Etiology and results of treatment of adults with bacterial encephalomeningitis]

Results of treatment and outcomes of 89 adults with purulent encephalomeningitis, treated in years 1996-2002 in the Department of Infectious Diseases and Hepatology, Medical University of Lodz, were analyzed. Eighty nine patients were retrospectively included into the study. Results of treatment were evaluated at the last day of patient's hospitalization, and classified as: cure, disability or death. Results of treatment were analyzed in relation to etiology of purulent encephalomeningitis, age and gender of patients, course of the disease, and time from the onset of symptoms to admission to the Department. No statistically significant correlations between age, gender and prognosis were found. Thirty seven out of 89 patients were cured (41.6%); 29 of 89 patients died (32.6%); in 18 patients (19/89; 20.2) disability was diagnosed. In remaining 5 cases (5.6%), the result of treatment remained unknown. These patients were transferred to Intensive Care Units, outside our Hospital. In the studied group, etiologic factor was identified in 40 out of 89 cases (44.9%). In 40 patients, positive results of bacterial examination of cerebrospinal fluid were achieved. In 22 out of these 40 cases (55.0%), Streptococcus pneumoniae was identified as the etiologic factor. Higher percentage of patients died in subgroup with known etiology than in in subgroup of unknown etiology (p = 0.02). Higher percentage of cases with unconsciousness and higher percentage of cases with respiratory insufficiency were diagnosed in patients who died, than in patients who were cured (p = 0.00001).

CONCLUSION

1. Purulent meningoencephalitis in adults, despite progress in antibiotic treatment, is still a serious condition, with poor prognosis. 2. Diagnostics and treatment modalities of purulent meningo-encephalitis should be urgently extended in order to achieve better outcomes in these group of patients.

[Pathogenesis of the lethal postoperative cerebral inflammatory-purulent complications in neurooncological patients]

The main and immediate causes of death, pathogenetic mechanisms of postoperative cerebral inflammatory-purulent complications (CIPC) in patients, suffering the brain tumour, were analyzed. The main pathogenetic patterns of the postoperative period course in the CIPC occurrence were studied, basing on the data of analysis of 30 patients, who died after the operation. There was proved, that the sepsis occurrence on the background of postoperative meningoencephalitis means the lethal ending of the disease. There was established, that in occurrence of septic complications, connected with postoperative meningoencephalitis, the most frequently the affection of respiratory and urinary systems occurs.

Ciclosporin use in multi-drug therapy for meningoencephalomyelitis of unknown aetiology in dogs

OBJECTIVE

To evaluate the efficacy and safety of ciclosporin therapy alone or in combination with corticosteroids and/or ketoconazole in dogs with diagnosis of meningoencephalomyelitis of unknown aetiology.

METHODS

Medical records of 10 dogs diagnosed with meningoencephalomyelitis of unknown aetiology and treated with ciclosporin therapy alone or in combination with corticosteroids and/or ketoconazole were reviewed at the Veterinary Medical Teaching Hospital, University of Wisconsin-Madison. Laboratory abnormalities, side effects, clinical and cerebrospinal fluid responses to treatment and association between blood ciclosporin level and response to treatment were evaluated. Histopathological diagnosis was available in three patients.

RESULTS

No significant abnormalities were detected on serial complete blood count and serum chemistry panel in any of the dogs. Side effects of ciclosporin therapy included excessive shedding, gingival hyperplasia and hypertrichosis. Overall median survival time for all dogs in the study was 930 days (range, 60 to more than 1290 days). In all dogs, serial cerebrospinal fluid analysis showed a marked improvement in the inflammation.

CLINICAL SIGNIFICANCE

Results suggest that ciclosporin either alone or in combination with ketoconazole may be a safe and effective treatment for meningoencephalomyelitis of unknown aetiology in dogs.

Human Herpesvirus 6 Meningoencephalitis in Allogeneic Hematopoietic Stem Cell Transplant Recipients

We retrospectively investigated the clinical characteristics of human herpesvirus 6 (HHV-6) meningoencephalitis within 100 days after allogeneic hematopoietic stem cell transplantation (HSCT). Of 1148 patients who received transplants between January 1999 and December 2003, 11 patients (0.96%) with HHV-6 meningoencephalitis were identified. Ten of 11 recipients received hematopoietic stem cells from donors other than HLA-identical siblings. Confusion was the most frequent central nervous system (CNS) symptom, and a skin rash with high-grade fever preceded the CNS symptoms in 9 patients. Magnetic resonance imaging of the brain showed an abnormal increased T2 signal in the hypothalamus of 5 patients. Eight patients were treated with ganciclovir, and an improvement of CNS symptoms was obtained in 3 patients; 3 patients treated with acyclovir showed no improvement. Improvement in the meningoencephalitis seemed less frequent in patients with abnormal findings in the hypothalamus than in those without such findings. Because the symptoms of HHV-6 meningoencephalitis mimicked those of cyclosporine- or tacrolimus-induced encephalopathy, the drugs were withdrawn at the onset of CNS symptoms in 10 patients, resulting in the development of grade IV graft-versus-host disease (GVHD) in 5 patients. Three patients died of HHV-6 meningoencephalitis, and 6 died of other causes, including GVHD. In conclusion, HHV-6 meningoencephalitis is a rare but potentially life-threatening complication in patients who undergo allogeneic HSCT. Careful assessment of the clinical findings and the brain may allow early and precise diagnosis of HHV-6 meningoencephalitis and contribute to improving its prognosis.

Combined cytosine arabinoside and prednisone therapy for meningoencephalitis of unknown aetiology in 10 dogs

OBJECTIVES

The differential diagnosis for young to middle-aged dogs with progressive neurological signs, focal or multifocal computed tomography/magnetic resonance imaging lesions, mononuclear cerebrospinal fluid pleocytosis and negative infectious titres includes granulomatous meningoencephalomyelitis, breed-specific meningoencephalitis, infectious meningoencephalitis of unknown origin and central nervous system neoplasia. The terminology meningoencephalitis of unknown aetiology may be preferable for cases that lack histopathological diagnoses. The safety and efficacy of a combination of cytosine arabinoside and prednisone protocol is evaluated, in this study, for the treatment of meningoencephalitis of unknown aetiology in 10 dogs.

METHODS

Cases were selected based on neuroanatomical localisation, negative regional infectious disease titres, cerebrospinal fluid pleocytosis and brain imaging. Clinical response was gauged through follow-up examinations, owner and referring veterinarian surveys and review of medical records.

RESULTS

Partial or complete remission was achieved in all dogs; the median survival time for the 10 dogs was 531 days (range 46 to 1025 days), with five of the 10 dogs alive at the time of writing.

CLINICAL SIGNIFICANCE

Prednisone/cytosine arabinoside is a safe empirical therapy for dogs with meningoencephalitis of unknown aetiology; this drug combination may prolong survival time.

Increase in viral meningitis cases reported in the Autonomous Region of Madrid, Spain, 2006

Between 1 January and 16 September 2006, the Epidemiological Surveillance Network of the Autonomous Region of Madrid detected 446 cases of viral meningitis

Synergistic activities of azithromycin and amphotericin B against Naegleria fowleri in vitro and in a mouse model of primary amebic meningoencephalitis

Naegleria fowleri is responsible for producing a rapidly fatal central nervous system infection known as primary amebic meningoencephalitis (PAM). To date, amphotericin B, an antifungal agent, is the only agent with established clinical efficacy in the treatment of PAM. However, amphotericin B is not always successful in treating PAM and is associated with severe adverse effects. We previously found azithromycin to be more effective than amphotericin B in a mouse model of PAM. We therefore investigated the combination of amphotericin B and azithromycin in vitro and in a mouse model of PAM. For the in vitro studies, 50% inhibitory concentrations were calculated for each drug alone and for the drugs in fixed combination ratios of 1:1, 3:1, and 1:3. We found amphotericin B and azithromycin to be synergistic at all three of the fixed combination ratios. In our mouse model of PAM, a combination of amphotericin B (2.5 mg/kg of body weight) and azithromycin (25 mg/kg) protected 100% of the mice, whereas amphotericin B alone (2.5 mg/kg) protected only 27% of mice and azithromycin alone (25 mg/kg) protected 40% of mice. This study indicates that amphotericin B and azithromycin are synergistic against the Lee strain of N. fowleri, suggesting that the combined use of these agents may be beneficial in treating PAM.

A rare and often unrecognized cerebromeningitis and hemodynamic disorder: a major cause of sudden death in somatic cell cloned piglets

In this study, we generated 40 somatic cell cloned (scNT) piglets. Of these, five piglets were stillborn, 22 scNT piglets died suddenly within the first week of life, and 1 piglet died after 40 days. Twelve scNT piglets are still healthy. The birth weights of compromised scNT piglets in comparison with those of normal scNT piglets are significantly reduced (0.80 +/- 0.29 vs 1.27 +/- 0.30 kg, p < 0.05), in spite of longer gestation (114 versus 120 day). Significant findings from histological examinations showed that approximately 25% (7/28) of scNT piglets showed severe congestion of lung and liver or neutrophilic inflammation in brain indicating that unexpected phenotypes can appear as a result of somatic cell cloning. Two-dimensional gel electrophoresis experiments revealed changes in the responses of several detoxification-related proteins related to stress and inflammation and found significant alterations in myocardium-specific proteins, indicating hemodynamic disorder. scNT piglets that survived to adulthood did not show any abnormality except skin and hair color depigmentation. The present study suggests that cerebromeningitis and hemodynamic disorder are a major risk factor for sudden early death of scNT piglets. Although we cannot completely exclude the possibility that scNT piglets are susceptible to specific respiratory infections, our data suggests that the early death of scNT clones is due to cardiopulmonary functional abnormalities and cerebromeningitis.

Clinical assessment of the entry into neurological state in rat experimental African trypanosomiasis

Human African trypanosomiasis, caused by Trypanosoma brucei (T.b.) gambiense or rhodesiense, evolves in two stages: haemolymphatic stage and meningo-encephalitic stages, the latter featuring numerous neurological disorders. In experimental models infected with diverse T.b. sub-species, body weight (BW) loss, drop in food intake (FI), and hypo-activity after an asymptomatic period suggest the occurrence of a similar two-stage organization. In addition to daily measurement of BW and FI, body core temperature (T(co)) and spontaneous activity (SA) were recorded by telemetry in T.b. brucei-infected rats. After a 10--12-day symptom-free period, a complex clinical syndrome occurred suddenly. If the animal survived the access, the syndrome re-occurred at approximately 5-day intervals until death. The syndrome was made of a drop in FI and BW, a sharp decrease in T(co) and a loss of SA, suggesting a brisk alteration of the central nervous system functioning. Such events confirm the existence of a two-stage disease development in experimental trypanosomiasis. The entry into the second stage is marked by the occurrence of the first access, BW follow-up being essential and often sufficient its determination.

Intranasal coadministration of the Cry1Ac protoxin with amoebal lysates increases protection against Naegleria fowleri meningoencephalitis

Cry1Ac protoxin has potent mucosal and systemic adjuvant effects on antibody responses to proteins or polysaccharides. In this work, we examined whether Cry1Ac increased protective immunity against fatal Naegleria fowleri infection in mice, which resembles human primary amoebic meningoencephalitis. Higher immunoglobulin G (IgG) than IgA anti-N. fowleri responses were elicited in the serum and tracheopulmonary fluids of mice immunized by the intranasal or intraperitoneal route with N. fowleri lysates either alone or with Cry1Ac or cholera toxin. Superior protection against a lethal challenge with 5 x 10(4) live N. fowleri trophozoites was achieved for immunization by the intranasal route. Intranasal immunization of N. fowleri lysates coadministered with Cry1Ac increased survival to 100%; interestingly, immunization with Cry1Ac alone conferred similar protection to that achieved with amoebal lysates alone (60%). When mice intranasally immunized with Cry1Ac plus lysates were challenged with amoebae, both IgG and IgA mucosal responses were rapidly increased, but only the increased IgG response persisted until day 60 in surviving mice. The brief rise in the level of specific mucosal IgA does not exclude the role that this isotype may play in the early defense against this parasite, since higher IgA responses were detected in nasal fluids of mice intranasally immunized with lysates plus either Cry1Ac or cholera toxin, which, indeed, were the treatments that provided the major protection levels. In contrast, serum antibody responses do not seem to be related to the protection level achieved. Both acquired and innate immune systems seem to play a role in host defense against N. fowleri infection, but further studies are required to elucidate the mechanisms involved in protective effects conferred by Cry1Ac, which may be a valuable tool to improve mucosal vaccines.

West Nile virus encephalitis in organ transplant recipients: another high-risk group for meningoencephalitis and death

West Nile virus infection has been spreading westward across the continental United States since 1999. Although it often presents as a mild, self-limiting viral illness, it can result in a devastating meningoencephalitis in some patient populations, particularly the elderly. We report in this article on two immunosuppressed transplant patients who developed a severe meningoencephalitis caused by mosquito-borne West Nile virus infection. Suggestions for the prevention, diagnosis, and treatment of West Nile virus infection in this patient population are described.

Review of clinical presentations in Thai patients with primary amoebic meningoencephalitis

CONTEXT

Primary amoebic meningoencephalitis (PAM) is a very rare but deadly infection of the central nervous system. Since the disease was first identified in 1965, fewer than 200 cases have been observed worldwide.

OBJECTIVE

The author performed a literature review of the reports of PAM in Thailand in order to study the clinical summary of PAM among Thai patients.

DESIGN

This study was designed as a descriptive retrospective study. A literature review of the papers concerning PAM in Thailand was performed.

RESULTS

According to this study, there have been at least 12 reports of PAM in Thailand, of which 2 cases were nonlethal. The mean age was 15.2 +/- 16.1 years with a male:female ratio of about 2:1. History of risk behaviors such as suffocation of surface water during swimming was demonstrated in 6 cases. Also, 2 interesting cases involved possible water contact according to the Thai tradition and culture. Concerning the patients' clinical features, fever, headache, impaired consciousness, and stiff neck were seen in all cases. However, some unusual presentations such as intermittent abdominal pain and convulsion were also seen in this series. Similar to worldwide findings, most cases occurred during the summer months. Most of the cases involved young males from rural provinces in various regions of Thailand. Concerning the laboratory investigation, the cerebrospinal fluid (CSF) profile presented the polymorphonuclear (PMN) pleomorphic with hypoglycorhachia pattern. Trophozoite could be identified in all but 2 cases in this series.

CONCLUSION

PAM is sporadically reported in Thailand but remains a public health issue. The clinical diagnosis of PAM is usually difficult as many clinicians are unfamiliar with the disease. The prognosis outcome is usually grave although broad medications are prescribed.

Fatal fulminant pan-meningo-polioencephalitis due to West Nile virus

We report a case of fatal fulminant West Nile virus (WNV) meningoencephalitis in an 87-year-old white male gardener. The Pennsylvania patient presented with a 3-day history of flu-like symptoms. His hospital course was gravely precipitous with onset of coma, ventilator dependence, loss of cortical and brainstem functions within ten days of admission. Acute serum and cerebrospinal fluid samples revealed elevated levels of WNV IgM antibodies by ELISA as well as elevated CSF white blood cells, protein and glucose. A complete autopsy revealed a multifocal lymphocytic myocarditis and severe chronic tubulointerstitial nephritis. Viral culture and PCR analysis of post-mortem samples of the spleen, kidney and brain were positive for WNV. Histological sections from all regions of the brain and spinal cord demonstrated a severe, non-necrotizing, subacute, polio-meningoencephalitis. While both gray and white matter were inflamed, gray matter was much more severely involved. Many gray matter nuclei showed severe neuronal loss with residual dying neurons surrounded by activated microglia. Immunohistochemical stains revealed profuse infiltration of the meninges and cerebral parenchyma by CD8 T-lymphocytes and perivascular B-lymphocytes. Electron micrographs revealed diffuse intracellular and extracellular edema but no viral particles were identified. Immunohistochemical and immunofluorescent staining for WNV filled the cytoplasm of residual neurons. West Nile virus mediates a predominantly polioencephalitis secondary to direct infection of neurons.

Identification of Naegleria fowleri in domestic water sources by nested PCR

The free-living amoeboflagellate Naegleria fowleri is the causative agent of primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system. In the United States, the disease is generally acquired while swimming and diving in freshwater lakes and ponds. In addition to swimming, exposure to N. fowleri and the associated disease can occur by total submersion in bathwater or small backyard wading pools. In the present study, swipe samples and residual pipe water from homes in Arizona were examined for N. fowleri by nested PCR due to the death of two previously healthy children from PAM. Since neither child had a history of swimming in a freshwater lake or pond prior to the onset of disease symptoms, the domestic water supply was the suspected source of infection. Of 19 samples collected from bathroom and kitchen pipes and sink traps, 17 samples were positive for N. fowleri by PCR. A sample from a Micro-Wynd II filter was obtained by passing water from bathtubs through the filter. Organisms attached to the filter also tested positive by PCR. The two samples that tested negative for N. fowleri were one that was obtained from a kitchen sink trap and a swipe sample from the garbage disposal of one home.

A fatal case of Vibrio vulnificus meningoencephalitis

The objective of this paper is to report a rare case of Vibrio vulnificus presenting as meningoencephalitis without a wound infection. Vibrio vulnificus is capable of causing severe and often fatal infections in susceptible individuals. It commonly causes necrotizing wound infections, primary septicemia, and gastroenteritis. A 69-year-old man had meningoencephalitis with lesion on the red nucleus, substantia nigra, basal ganglia, and dentate nucleus as the initial clinical manifestation of a V. vulnificus infection. This is the first case of V. vulnificus infection in which MRI demonstrated the involvement of deep nuclei of the brain.

Anthrax meningoencephalitis

OBJECTIVE

To review reported cases of anthrax meningoencephalitis and describe the clinical findings, diagnostic test results, treatment, and outcome over the past 50 years.

METHODS

Retrospective review of English language articles published since Haight's (1952) review.

RESULTS

Thirty-four core articles were identified, describing 70 patients with cutaneous (29%), gastrointestinal (17%), inhalational (39%), and unknown (16%) sources of infection. Clinical signs on presentation included fever, malaise, meningeal signs, hyperreflexia, and delirium, stupor, or coma. CSF analyses demonstrated hemorrhagic meningitis, with positive Gram's stains and CSF cultures. Many patients presented in extremis following a prodromal period of 1 to 6 days, and 75% died within 24 hours of presentation. Despite aggressive treatment in many cases, only 6% (4 of 70) survived, none of whom had pulmonary anthrax. Surviving patients generally had a cutaneous portal of entry, were younger, and had less severely abnormal initial CSF results than patients who died. Most of the survivors recovered fully. Pathologic findings included hemorrhagic meningitis, multifocal subarachnoid and intraparenchymal hemorrhages, vasculitis, and cerebral edema.

CONCLUSIONS

Anthrax meningoencephalitis has a high case-fatality rate, even with aggressive antibiotic treatment and supportive therapy. Hemorrhagic meningitis should raise suspicion of anthrax infection, particularly if gram-positive rods are demonstrated on Gram's stain. Anthrax meningoencephalitis can develop from any primary focus, but survival appears to be most likely if meningoencephalitis develops from cutaneous anthrax. Treatment of surviving patients was generally begun before signs and symptoms of meningoencephalitis were present.

Tick-borne encephalitis (TBE) in Germany and clinical course of the disease

Between 1991 and 2000 about 1500 patients fell ill in Germany (Baden-Wuerttemberg, Bavaria, Hesse) after infection with the tick-borne encephalitis (TBE) virus. Detailed clinical and epidemiological data of TBE were available from 850 patients. A biphasic course of the disease occurred in 75% of patients. TBE presented as meningitis in 400 patients (47%), as meningoencephalitis in 356 (42%) and as meningoencephalomyelitis in 93 (11%). Nine of the patients (1%) died from TBE. Five hundred and ninety three patients (70%) had noticed a tick bite and the first symptoms occurred, on average, seven days later. The most frequent neurological symptoms were an impairment of consciousness (31%), ataxia (18%) and paresis of the extremities (15%) and cranial nerves (11%). Laboratory investigations revealed leukocytosis in the peripheral blood in 74% of the patients, elevation of the sedimentation rate in 91%, increased C-reactive protein in 82%, pleocytosis in the CSF of all patients tested, damage of the blood-CSF-barrier in 79%, abnormalities in EEG in 77% and abnormalities in MRI in 18%. In general, adolescents up to 14 years of age had a more favourable course of the disease than adults. In view of the severity of the illness and the high frequency of sequelae, active immunisation against TBE is recommended for all subjects living in and travelling to areas of risk. Regarding the higher risk of severe manifestations of TBE in the elderly patients and the higher risk of failure of immunisation in this population, vaccination against TBE is more important in elderly subjects than in very young persons. Prevention of TBE by post exposure prophylaxis with hyperimmunoglobulins is less effective and should therefore not be performed.

Assessing the risk of primary amoebic meningoencephalitis from swimming in the presence of environmental Naegleria fowleri

Free-living Naegleria fowleri amoebae cause primary amoebic meningoencephalitis (PAM). Because of the apparent conflict between their ubiquity and the rarity of cases observed, we sought to develop a model characterizing the risk of PAM after swimming as a function of the concentration of N. fowleri. The probability of death from PAM as a function of the number of amoebae inhaled is modeled according to results obtained from animals infected with amoeba strains. The calculation of the probability of inhaling one or more amoebae while swimming is based on a double hypothesis: that the distribution of amoebae in the water follows a Poisson distribution and that the mean quantity of water inhaled while swimming is 10 ml. The risk of PAM for a given concentration of amoebae is then obtained by summing the following products: the probability of inhaling n amoebae x the probability of PAM associated with inhaling these n amoebae. We chose the lognormal model to assess the risk of PAM because it yielded the best analysis of the studentized residuals. Nonetheless, the levels of risk thereby obtained cannot be applied to humans without correction, because they are substantially greater than those indicated by available epidemiologic data. The curve was thus adjusted by a factor calculated with the least-squares method. This provides the PAM risk in humans as a function of the N. fowleri concentration in the river. For example, the risk is 8.5 x 10(-8) at a concentration of 10 N. fowleri amoebae per liter.

The differential roles of LFA-1 and Mac-1 in host defense against systemic infection with Streptococcus pneumoniae

Mice deficient in CD18, which lack all four CD11 integrins, have leukocytosis and increased susceptibility to bacterial infection. To determine the effect of deficiencies in LFA-1 (CD11a/CD18) or Mac-1 (CD11b/CD18) on host defense against systemic bacterial infection, knockout mice were inoculated i.p. with Streptococcus pneumoniae. Increased mortality occurred in both LFA-1(-/-) (15 of 17 vs 13 of 35 in wild type (WT), p < 0.01) and Mac-1(-/-) (17 of 34 vs 6 of 25, p < 0.01) mice. All deaths in LFA-1(-/-) mice occurred after 72 h, whereas most deaths in Mac-1(-/-) mice occurred within 24-48 h. At 24 h, 21 of 27 Mac-1(-/-) mice were bacteremic, vs 15 of 25 WT (p = 0.05); no difference was observed between LFA-1(-/-) and WT. Increased bacteria were recovered from Mac-1(-/-) spleens at 2 h (p = 0.03) and 6 h (p = 0.002) and from livers (p = 0.001) by 6 h. No difference was observed at 2 h in LFA-1(-/-) mice, but by 6 h increased bacteria were recovered from spleens (p = 0.008) and livers (p = 0.04). Baseline and peak leukocyte counts were similar between Mac-1(-/-) and WT, but elevated in LFA-1(-/-). At 8 h, peritoneal neutrophils were increased in Mac-1(-/-), but not significantly different in LFA-1(-/-). Histopathologically, at 24 h Mac-1(-/-) animals had bacteremia and lymphoid depletion, consistent with sepsis. LFA-1(-/-) mice had increased incidence of otitis media and meningitis/encephalitis vs WT at 72 and 96 h. Both Mac-1 and LFA-1 play important but distinct roles in host defense to S. pneumoniae.

[Criteria of the unfavorable course of meningoencephalitis of rhinogenic origin]

The paper presents the data on 318 patients who visited "Diagnostics" Medical Centre. Among the patients there were 195 women (61%) and 123 men (39%) aged 9-71 years. Somatizated mental pathology was diagnosed in 306 cases. A cohort of the patients examined reflected quite adequately both the frequency and the types of mental pathology, exactly: neurotic, personal, psychotic and organic (somatic). But these patients did not received necessary psychiatric aid. Clinical, cultural and social-psychological causes of this situation are considered. Among such causes there is deterioration of both dispensary and ambulatory-polyclinic psychiatric service.

[Early-summer meningo-encephalitis (ESME) and ESME-vaccination: status 2000]

Tick-borne encephalitis (TBE) is a public health problem very well under control in Austria because of a vaccination programme using a safe, efficient and well tolerated vaccine and a carefully designed social marketing concept. The Austrian vaccine underwent another technological updating and is now marketed under a new brand name (TicoVac) on the basis of an EU registration. A second product is also available (Encepur), but some limitations of use have to be taken into account. To improve the epidemiological situation even further (only 41 hospital cases in 1999) special attention has to be given to the age group 50 years and older as this is the segment of the population where the majority of cases is observed. TBE is a growing international health problem as awareness increases and cases are identified in many European countries, even in regions where TBE so far was not diagnosed. An "International Scientific Working-group on Tick-borne encephalitis (ISW-TBE)" was established to coordinate research and public health activities.

[Prognosis factors in cryptococcal meningoencephalitis]

OBJECTIVE

To identify demographic, clinical and cerebrospinal fluid (CSF) variables associated to intrahospitalar lethality of patients with cryptococcal meningoencephalitis.

STUDY DESIGN

Retrospective cohort to study prognosis.

SETTING

Hospital Couto Maia (HCMaia) reference for patients with infectious diseases in the State of Bahia Northeastern Brazil.

POPULATION

Patients admitted at HCMaia, from 1972 to 1996, with the diagnosis of cryptococcal meningoencephalitis.

RESULTS

Lethality rate was 42.7%. The most important neurological abnormalities were neck stiffness, decreased consciousness level, behavior changes, cranial nerve palsy and visual alteration. Disease time over 30 days, involvement of consciousness level and cerebrospinal fluid cells under 40/mm3 were associated to a higher lethality rate.

CONCLUSION

Disease time over 30 days, involvement of consciousness level, and CSF decreased cellularity were the only predictors of lethality in the studied population.

Phosphatidylcholine-specific phospholipase C from Listeria monocytogenes is an important virulence factor in murine cerebral listeriosis

Meningoencephalitis is a serious and often fatal complication of Listeria monocytogenes infection. The aim of the present study was to analyze the role of internalin A (InlA) and B, which are involved in the invasion of L. monocytogenes into cultivated host tissue cells, and that of phosphatidylcholine-specific phospholipase C (PlcB), which mainly promotes the direct cell-to-cell spread of L. monocytogenes, in murine cerebral listeriosis by use of an InlA/B (DeltainlAB2)- and a PlcB (DeltaplcB2)-deficient isogenic deletion mutant strain and the wild-type (WT) L. monocytogenes EGD. Listeria strains were directly applied to the brain, a technique which has been employed previously to study the pathogenesis of cerebral listeriosis (D. Schlüter, S. B. Oprisiu, S. Chahoud, D. Weiner, O. D. Wiestler, H. Hof, and M. Deckert-Schlüter, Eur. J. Immunol. 25:2384-2391, 1995). We demonstrated that PlcB, but not InlA or InlB, is an important virulence factor in cerebral listeriosis. Nonimmunized mice infected intracerebrally with the DeltaplcB2 strain survived significantly longer and had a reduced intracerebral bacterial load compared to mice infected with the DeltainlAB2 strain or WT bacteria. In addition, immunization with the WT prior to intracerebral infection significantly increased the survival rate of mice challenged intracerebrally with the DeltaplcB2 strain compared to that of mice infected with the WT or DeltainlAB2 strain. Histopathology revealed that the major difference between the various experimental groups was a significantly delayed intracerebral spread of the DeltaplcB2 mutant strain, indicating that cell-to-cell spread is an important pathogenic feature of cerebral listeriosis. Interestingly, irrespective of the Listeria mutant used, the apoptosis of hippocampal and cerebellar neurons and an internal hydrocephalus developed in surviving mice, indicating that these complications are not dependent on the virulence factors InlA/B and PlcB. In conclusion, this study points to PlcB as a virulence factor important for the intracerebral pathogenesis of murine L. monocytogenes meningoencephalitis.

[Prognostic factors of tuberculous meningoencephalitis lethality]

In order to describe the lethality predictors of patients with tuberculous meningoencephalitis, records of 231 patients were analysed. Ages ranged from less than 1 year to 68 years. Ninety-seven patients (42%) were four years old or less. Apart from 73.2% of patients whose diagnosis was performed by clinical and epidemiologic criteria associated with response to specific therapy, 26.8% had diagnostic confirmation through cerebrospinal fluid (culture, bacilloscopy, PCR) or necropsy. The lethality predictors were: less than 4 years of age, seizures, and severe alterations of consciousness.

Development of specific nested oligonucleotide PCR primers for the Streptococcus iniae 16S-23S ribosomal DNA intergenic spacer

Streptococcus iniae is a cause of septicemia, meningoencephalitis, and death in farmed fish and of cellulitis in human beings. A set of nested oligonucleotide PCR primers that specifically amplified a 373-bp subunit from a variety of clinical isolates from farmed fish and human patients were constructed from a 524-bp consensus sequence of the S. iniae 16S-23S ribosomal DNA intergenic spacer.

Prognostic factors for dogs with granulomatous meningoencephalomyelitis: 42 cases (1982-1996)

OBJECTIVE

To assess signalment, clinical signs, results of CSF analysis, treatment, and survival times in dogs with granulomatous meningoencephalomyelitis (GME) and to identify factors associated with survival.

DESIGN

Retrospective study.

SAMPLE POPULATION

Medical records of 42 dogs with GME.

PROCEDURE

Information on signalment, neurolocalization, presence of focal or multifocal signs, results of CSF analysis, method of treatment, and time from onset of clinical signs to death was retrieved from medical records of each dog. Kaplan-Meier survival analysis was used to assess survival times. The Cox proportional hazards method was used to identify predictors of survival.

RESULTS

Females and toy and terrier breeds were predisposed to GME. Half of the dogs had focal neurologic signs, and half had multifocal involvement. Clinical signs referable to the forebrain were most common with focal involvement, whereas signs referable to the forebrain and brainstem were most commonly seen with multifocal involvement. Cerebrospinal fluid analysis commonly revealed a mononuclear pleocytosis. Survival times ranged from 1 to > 1,215 days. Significant differences in survival times were demonstrated for the following factors: focal versus multifocal clinical signs, neurolocalization of focal signs, and treatment with radiation. Radiation was the only independent predictor of survival.

CLINICAL IMPLICATIONS

Dogs with signs suggesting focal involvement of GME tend to survive longer than those with multifocal involvement. Radiation is an effective treatment for dogs with GME, particularly those with clinical signs suggesting focal involvement.

Modified Glasgow Coma Scale to predict mortality in children with acute infections of the central nervous system

BACKGROUND

This study aimed to identify the predictors of hospital mortality in children with acute infective disorders of the central nervous system using an aggregate Modified Glasgow Coma Scale (MGCS) score and other clinical variables assessed within 24 hours of hospitalization.

METHODS

We did a prospective cohort study in a teaching and referral hospital in Lucknow, North India. Consecutive children aged 1 month to 12 years of age admitted with acute infective disorders of the central nervous system were included in the study. The diagnosis was based on the presence of symptoms of fever, headache or irritability with or without vomiting, and either altered sensorium or first episode of seizures or both. The main outcome measure was hospital-based mortality.

RESULTS

Of the 230 patients included in the study, 42.2% had pyogenic meningitis, 36.9% had tuberculous basal meningitis and 20.9% had meningo-encephalitis. There were 43 (18.7%) deaths of which 44.2% were within 3 days of admission. Death was associated with the day 1 aggregate MGCS score only. The area under the curve of four strata of aggregate MGCS was 0.63 (SE 0.05). The likelihood ratio for discharge with an aggregate MGCS score of < 5 was 0.52 (95% CI:0.29-0.95) and > 10 was 5.52 (9% CI:1.02-31.96).

CONCLUSION

The MGCS can be used to predict discharge in patients with acute infective disorders of the central nervous system within 24 hours of hospitalization. The scale is simple, can be applied at the bedside and does not depend on any investigations. In developing countries with limited investigative facilities it can be used for identification and selective referral of patients with a higher risk of death to specialized centres. This study validates the predictive value of the MGCS.

[Purulent meningoencephalitis--studies of disease progression and prognosis]

The course of acute purulent meningitis and meningocephalitis was investigated in 101 patients using records and a questionnaire directed to all patients. Patients who survived meningoencephalitis were asked to come to a neurological examination. Neuropsychological status, EEG and Tc-HMPAO-Spect were also performed in these patients. The patients were treated with a combination of three antimicrobial agents which was commonly used at our hospital during the investigation time consisting of penicillin, a cephalosporine of the third generation and an aminoglycoside. 40% of the patients suffered from more or less severe neurologic sequelae; remaining cognitive deficits were also frequent. On the whole there was a tendency towards improvement in patients who suffered from less severe deficits at the time of discharge from hospital, patients with more severe deficits also showed slight improvement but generally did not reach a restitutio ad integrum. Regarding this, in our opinion a broad initial antimicrobial therapy should be used, although a statistically significant improvement of the patient's outcome by this could not be shown. Lethality as well as the frequency of complications do not seem to differ over many years although antimicrobial and intensive care treatment were improved. Thus, the outcome seems to depend largely on the occurrence of secondary focal complications or brain oedema.

An epidemic of food-borne listeriosis in western Switzerland: description of 57 cases involving adults

This article describes 57 cases of listeriosis that occurred in adults in western Switzerland during an outbreak associated with the consumption of a soft cheese. Twenty-one percent of the cases were of bacteremia, 40% were of meningitis, and 39% were of meningoencephalitis. Overall, 42% of the patients had an underlying disease and 54% were > 65 years of age. Patients with bacteremia were significantly older than those with meningitis or meningoencephalitis (median ages, 75, 69, and 55 years, respectively). The epidemic strain, defined by phage typing, was isolated in three-quarters of the listerial cases observed during the epidemic period and did not appear to differ significantly from the nonepidemic strains in terms of virulence. The overall mortality associated with the 57 cases was 32%. Among the patients' characteristics, age and type of clinical presentation were independent predictors of death in a multivariate logistic regression model (pseudo-r2 [coefficient of determination], .26; both P values < .05), and a presentation of meningoencephalitis was associated with an increased death risk (odds ratio, 6.5; 95% confidence interval, 1.1-39.5; P < .05). Neurological sequelae developed in 30% of the survivors of CNS listeriosis.

Radiation therapy of canine brain masses

This article evaluates the responses of 14 dogs with brain masses using orthovoltage irradiation for definitive treatment. Dogs were anesthetized for computed tomography (CT) examination, formation of head immobilization and positioning devices, radiation treatment simulation, and treatments. Total doses of 39 Gy (9 dogs) or 45 Gy (5 dogs) to the tumor were administered over 25 to 41 days. Two or three portals (parallel opposed lateral with or without a dorsal field) were used. Treatment volumes included the tumor and peritumoral edema, as determined by CT scan, and a 1-cm margin. Histopathologic diagnoses were available in 9 of 14 dogs. There were 4 meningiomas, 1 lymphosarcoma, 1 pituitary adenoma, 1 metastatic anaplastic carcinoma, 1 anaplastic oligodendroglioma and 1 dog with granulomatous meningoencephalitis. At the end of radiation therapy, 10 dogs could be evaluated for progression of clinical signs: 3 dogs deteriorated or failed to improve, and 7 dogs improved. At the time of analysis, all dogs were dead. Mean and median survival times, measured from the beginning of radiation, were 345 and 489 days, respectively. This was compared with mean survival times of 30 to 81 days reported in the literature for dogs with brain tumors that did not receive treatment. The median survival time of 9 dogs treated with 39 Gy was 153 days, versus 519 days for 5 dogs that received 45 Gy. It appears that radiation therapy prolongs survival times for dogs with brain masses. Although megavoltage therapy would be optimal, orthovoltage radiation can be applied in total doses of 45 Gy in 3.75 Gy fractions over 28 days without adverse effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Up-to-date aspects of meningoencephalitis. Anatomo-clinical researches

The anatomo-clinical study of the deaths caused by meningoencephalitis at the Infectious Diseases Clinics in Bucharest in 1986 and 1987 showed the increase of morbidity, 194 lethal cases being registered. The most affected age group was up to 1 year, followed by older persons, then by children between 1 and 10 years, the male sex prevailing. The most incriminated pathogenic agents were meningococcus, pneumococcus, as well as negative Gram germs, Escherichia coli, whereas the favouring factors were especially malnutrition, premature birth, dystrophies, focal infections. The lesional pictures are described, underlying the frequency of vascular lesions, ventriculitis cerebral abscesses, as well as the role of demyelinizations and of the glial reactions in pathogenesis.

The fifth nonlethal case of primary amoebic meningoencephalitis

The fifth nonlethal case of primary amoebic meningoencephalitis was reported. He was a 61-year-old gardener from northeast Thailand who had an abrupt onset of high fever, headache and stupor. Lumbar puncture showed numerous naegleria in the cerebrospinal fluid. The combination of 0.5 mg/kg/day of intravenous amphotericin B for 14 days, oral rifampicin and oral ketoconazole for 1 month cured the patient with no recurrence after one year of follow-up. The authors emphasise the regimen of low dose amphotericin B for a prolonged period instead of a high dose over a short period.

[Clinical and echoencephalographic data in assessing the outcome of meningococcal meningoencephalitis]

The authors made a clinical analysis of outcomes of meningococcal meningoencephalitis in 100 patients with consciousness disturbances. It was established that the outcome of the disease depended on the time of hospitalization and degree of disturbed consciousness. The dynamics of neurological symptoms and echoencephalography of brain edema is of importance in evaluation of the prognosis of meningoencephalitis.

Eosinophilic meningoencephalitis due to Angiostrongylus cantonensis as the cause of death in captive non-human primates

Fatal eosinophilic meningoencephalitis due to Angiostrongylus cantonensis is reported in captive non-human primates. A howler monkey (Alouatta caraya) at the Audubon Park and Zoological Gardens, New Orleans, LA, died 21 days after initial clinical symptoms. A white-handed gibbon (Hylobates lar) died at the Ardastra Gardens and Zoo, Nassau, Bahamas, 17 days after onset of symptoms. Both had access to free-ranging gastropods within the zoos. These are the first reported cases of natural infection by A. cantonensis in non-human primates in the western hemisphere.

[Death caused by viral meningoencephalitis in a caseload of 1052 cases]

1,052 medical records of patients discharged from "Pedro Borrás Astorga" Pediatric Teaching Hospital, with a diagnosis of non-urlean viral meningoencephalitis in the period ranging from October 1, 1985 to March 31, 1986, were reviewed. In this study the medical records of three deaths were particularly analyzed by means of the data of highest interest such as: age, sex, color of skin, length of stay, diagnostic impression at admission, motive of admission, course of the disease, physical examination and complementary procedures, and particularly anatomopathologic results. Conclusions are provided.

Encephalitis and aseptic meningitis, Olmsted County, Minnesota, 1950-1981: I. Epidemiology

All cases fulfilling stated criteria for encephalitis and aseptic meningitis in Olmsted County, Minnesota, for the period 1950 through 1981 were identified. This is, to our knowledge, the first such incidence and trend study in a delineated population, providing rates per 100,000 person-years of 7.4 for encephalitis (189 cases) and 10.9 for aseptic meningitis (283 cases). These are about twelve and six times higher, respectively, than the rates reported by the Centers for Disease Control. The rates have been stable over successive 5- or 10-year periods except for a recent increase in aseptic meningitis. Both conditions were more common in the summer months, in childhood, and among males. Viral identification using conventional laboratory tests has improved with time; in the period 1970 through 1981, virus type was specified in about one-fourth of the cases. The most common agents identified were California and mumps viruses in encephalitis, and entero and mumps viruses in aseptic meningitis. Antecedent and/or concurrent infections were noted in 42 and 35% of encephalitis and aseptic meningitis cases, respectively. No case due to mumps, measles, or rubella viruses has occurred since 1972, reflecting the impact of immunizations. Recovery was reported at the end of the acute phase in 95% of patients with aseptic meningitis, and there were no deaths. Seventy-eight percent of encephalitis patients recovered completely; the case fatality rate was 3.8%. Of the encephalitis cases, 2% were diagnosed initially postmortem.

Immunization with killed Acanthamoeba culbertsoni antigen and amoeba culture supernatant antigen in experimental Acanthamoeba meningoencephalitis

Mice immunized with killed (sonicated) Acanthamoeba culbertsoni A-1 antigen displayed marked resistance to intranasal challenge with the amoeba. A primary immunization produced a survival rate of approximately 40%, and survival values of greater than 80% were obtained by multiple immunizations. Similarly mice immunized with fluids from A-1 cultures were highly resistant to infection.