Balamuthia mandrillaris amoebic encephalitis mimicking tuberculous meningitis.

A 76-year-old female with no apparent immunosuppressive conditions and no history of exposure to freshwater and international travel presented with headache and nausea 3 weeks before the presentation. On admission, her consciousness was E4V4V6. Cerebrospinal fluid analysis showed pleocytosis with mononuclear cell predominance, elevated protein, and decreased glucose. Despite antibiotic and antiviral therapy, her consciousness and neck stiffness gradually worsened, right eye-movement restriction appeared, and the right direct light reflex became absent. Brain magnetic resonance imaging revealed hydrocephalus in the inferior horn of the left lateral ventricle and meningeal enhancement around the brainstem and cerebellum. Tuberculous meningitis was suspected, and pyrazinamide, ethambutol, rifampicin, isoniazid, and dexamethasone were started. In addition, endoscopic biopsy was performed from the white matter around the inferior horn of the left lateral ventricle to exclude brain tumor. A brain biopsy specimen revealed eosinophilic round cytoplasm with vacuoles around blood vessels, and we diagnosed with amoebic encephalitis. We started azithromycin, flucytosine, rifampicin, and fluconazole, but her symptoms did not improve. She died 42 days after admission. In autopsy, the brain had not retained its structure due to autolysis. Hematoxylin and eosin staining of her brain biopsy specimen showed numerous amoebic cysts in the perivascular brain tissue. Analysis of the 16S ribosomal RNA region of amoebas from brain biopsy and autopsy specimens revealed a sequence consistent with Balamuthia mandrillaris. Amoebic meningoencephalitis can present with features characteristic of tuberculous meningitis, such as cranial nerve palsies, hydrocephalus, and basal meningeal enhancement. Difficulties in diagnosing amoebic meningoencephalitis are attributed to the following factors: (1) excluding tuberculous meningitis by microbial testing is difficult, (2) amoebic meningoencephalitis has low incidence and can occur without obvious exposure history, (3) invasive brain biopsy is essential in diagnosing amoebic meningoencephalitis. We should recognize the possibility of amoebic meningoencephalitis when evidence of tuberculosis meningitis cannot be demonstrated.

Fatal granulomatous amebic encephalitis initially presenting with a cutaneous lesion.

We present a case of a 66-year-old man with a cutaneous Balamuthia mandrillaris lesion that progressed to fatal granulomatous amoebic encephalitis. We provide a summary of Australian cases and describe the clinical features and approach to diagnosing this rare but devastating condition, including the importance of PCR for diagnosis.

Balamuthia mandrillaris Granulomatous Amoebic Encephalitis: The First African Experience.

We report the first case of Balamuthia mandrillaris granulomatous amoebic encephalitis definitively acquired in Africa. Our case emphasizes initial nonspecific dermatological features, delays in confirmation of the diagnosis, difficulties accessing recommended medication, and uncertainty about optimal treatment of a disease with a frequently fatal outcome.

Sequential infection of Epstein-Barr virus and cryptococcal encephalitis after umbilical cord blood transplantation in a child with X-linked adrenoleukodystrophy.

Dual infection with two pathogens can be found in few cases of encephalitis. Cases of sequential infection with EBV and cryptococcal encephalitis in post-transplant patients are rare. We describe a 5-year-old boy with X-linked adrenoleukodystrophy who presented sequential infection with EBV and cryptococcal encephalitis after umbilical cord blood transplant. The patient showed fever, vomiting and emotional agitation with EBV DNA detected in CSF on day 100. The child underwent 3 doses of intravenous rituximab with a good response. However, the child presented with right facial paralysis, headache, and fever on day 130 after 2 weeks of clinical stability. Brain MRI demonstrated chronic granuloma formed with ring enhancement. FilmArray ME PCR confirmed the existence of Cryptococcus neoformans/gattii in the CSF. The child underwent sequential treatment with amphotericin liposome B and flucytosine. Maintenance treatment with fluconazole was administered for 1 year. Facial paralysis was on longer present on day 260. Cryptococcus neoformans/gattii was not detected on day 310. The biochemistry and cell count of the CSF were completely normal on day 520. Follow-up 2.5 years after presentation, brain MRI changes showed near complete resolution of the lesions. The child survived for 3 years to the last following-up. Invasive cryptococcal encephalitis is rare and life-threatening complication of transplantation. It is important to recognize dual infections, and perform treatment quickly to improve the prognosis of encephalitis after transplantation.

Scratching Past Lymphadenopathy: A Case of Bartonella henselae Encephalitis.

A previously healthy 6-year-old boy presented with new onset seizure activity and altered mental status. His prehospital course included prolonged fever, vague abdominal complaints, and unusual behavior. Neurological testing was unrevealing, and his symptoms slowly improved without intervention. His primary pediatrician had ordered serum antibody titers to Bartonella henselae for testing of prolonged fever in the setting of exposure to a kitten; these were found to be positive for both immunoglobulin G and immunoglobulin M. Further examination for organ involvement revealed splenic and liver micro-abscesses. After completion of his antibiotic course, the patient returned to his cognitive and neurologic baseline with resolution of his abdominal abscesses. This case emphasizes the importance of obtaining a thorough exposure history when evaluating for infectious causes of encephalitis. [Pediatr Ann. 2020;49(8):e359-e362.].

A Surviving Case of Acanthamoeba Granulomatous Amebic Encephalitis in a Hematopoietic Stem Cell Transplant Recipient.

BACKGROUND Acanthamoeba are free-living amoebae with potential to infect immunocompromised hosts. The mortality rate of granulomatous amebic encephalitis (GAE) due to Acanthamoeba exceeds 90% and there are currently no reports of survival of this infection in recipients of hematopoietic stem cell transplant. CASE REPORT We report herein the case of a 32-year-old man presenting to our service with abrupt neurological deterioration and seizures 5 months after allogeneic stem cell transplantation for Hodgkin lymphoma. Clinical and imaging findings were non-specific at presentation. Multiple circumscribed, heterogenous, mass-like lesions were identified on MRI. Brain biopsy was performed and revealed multiple cysts and trophozoites suggesting a diagnosis of granulomatous amebic encephalitis. PCR testing confirmed Acanthamoeba. Treatment with miltefosine, metronidazole, azithromycin, fluconazole, pentamidine isethionate, and co-trimoxazole was instituted and the patient survived and shows continued improvement with intensive rehabilitation. CONCLUSIONS We report the first successful outcome in this setting. The diagnosis would have been missed on cerebrospinal fluid analysis alone, but was rapidly made by histological analysis of brain biopsy. This diagnostically challenging infection is likely under-recognized. Early brain biopsy and commencement of a prolonged miltefosine-containing anti-ameba regimen can be curative.

Acute Encephalitic Syndrome Induced by Scleromyxedema.

Dermato-neuro syndrome is a potentially fatal neurological complication of scleromyxedema consisting of fever, seizures, and coma. This is an overlooked scleromyxedema case of a 62-year-old female patient from 2-years ago. She was admitted to our ICU because of high fever, colloid speech, muscle ache, and nausea. Molecular methods in the cerebrospinal fluid for neurotropic viruses ruled out acute infectious encephalitis. Her thyroid hormones were within normal values while the serum protein electrophoresis confirmed the monoclonal gammopathy of immunoglobulin G lambda (IgG(λ)), known for the last 2 years. The subsequent bone-marrow biopsy excluded the development of multiple myeloma. The patient fulfilled fundamental diagnostic criteria of scleromyxedema (monoclonal gammopathy, normal thyroid function and the appearance of marked sclerosis and induration of the skin papules on the face, neck, extremities, and skin creases) presenting as dermato-neuro syndrome, which was histologically confirmed. She demonstrated a remarkable improvement after intravenous immunoglobulin treatment during the first 24 hours. Mimics of non-infectious acute encephalitis should include the clinical diagnosis of scleromyxedema, especially when patients present in the emergency department with acute fever, coma, and skin lesions of diffuse sclerodermoid and papular type.

Prospective Cohort Study of Next-Generation Sequencing as a Diagnostic Modality for Unexplained Encephalitis in Children.

BACKGROUND: Encephalitis is an inflammatory condition of the brain associated with long-term neurologic sequelae and even death in children. Although viruses are often implicated, an etiology is not identified in the majority of cases. Metagenomics-based next-generation sequencing (mNGS) is a high-throughput sequencing technique that can enhance the detection of novel or low-frequency pathogens. METHODS: Hospitalized immunocompetent children aged 6 months to 18 years with encephalitis of unidentified etiology were eligible for enrollment. Demographic, historical, and clinical information was obtained, and residual blood and cerebrospinal fluid (CSF) samples were subjected to mNGS. Pathogens were identified by querying the sequence data against the NCBI GenBank database. RESULTS: Twenty children were enrolled prospectively between 2013 and 2017. mNGS of CSF identified 7 nonhuman nucleic acid sequences of significant frequency in 6 patients, including that of Mycoplasma bovis, parvovirus B19, Neisseria meningitidis, and Balamuthia mandrillaris. mNGS also detected Cladophialophora species, tobacco mosaic virus, and human bocavirus, which were presumed to be contaminants or nonpathogenic organisms. One patient was found to have positive serology results for California encephalitis virus, but mNGS did not detect it. Patients for whom mNGS identified a diagnosis had a significantly higher CSF white blood cell count, a higher CSF protein concentration, and a lower CSF glucose level than patients for whom mNGS did not identify a diagnosis. CONCLUSION: We describe here the results of a prospective cohort analysis to evaluate mNGS as a diagnostic tool for children with unexplained encephalitis. Although mNGS detected multiple nonpathogenic organisms, it also identified multiple pathogens successfully and was most useful in patients with a CSF abnormality.

Balamuthia mandrillaris-Related Primary Amoebic Encephalitis in China Diagnosed by Next Generation Sequencing and a Review of the Literature.

BACKGROUND: Encephalitis is caused by infection, immune mediated diseases, or primary inflammatory diseases. Of all the causative infectious pathogens, 90% are viruses or bacteria. Granulomatous amoebic encephalitis (GAE), caused by Balamuthia mandrillaris, is a rare but life-threatening disease. Diagnosis and therapy are frequently delayed due to the lack of specific clinical manifestations. METHOD: A healthy 2 year old Chinese male patient initially presented with a nearly 2 month history of irregular fever. We present this case of granulomatous amoebic encephalitis caused by B. mandrillaris. Next generation sequencing of the patient's cerebrospinal fluid (CSF) was performed to identify an infectious agent. RESULT: The results of next generation sequencing of the CSF showed that most of the mapped reads belonged to Balamuthia mandrillaris. CONCLUSION: Next generation sequencing (NGS) is an unbiased and rapid diagnostic tool. The NGS method can be used for the rapid identification of causative pathogens. The NGS method should be widely applied in clinical practice and help clinicians provide direction for the diagnosis of diseases, especially for rare and difficult cases.

Fatal granulomatous amoebic encephalitis due to free-living amoebae in two boys in two different hospitals in Lima, Perú.

Granulomatous amoebic encephalitis caused by free-living amoebae is a rare condition that is difficult to diagnose and hard to treat, generally being fatal. Anti-amoebic treatment is often delayed because clinical signs and symptoms may hide the probable causing agent misleading the appropriate diagnostic test. There are four genera of free-living amoeba associated with human infection, Naegleria, Acanthamoeba sp., Balamuthia and Sappinia. Two boys were admitted with diagnosis of acute encephalitis. The history of having been in contact with swimming pools and rivers, supports the suspicion of an infection due to free-living amoebae. In both cases a brain biopsy was done, the histology confirmed granulomatous amoebic encephalitis with the presence of amoebic trophozoites.

Acanthamoeba and its pathogenic role in granulomatous amebic encephalitis.

Acanthamoeba is a free-living amoeba that is widely distributed in the environment. It is an opportunist protist, which is known to cause rare yet fatal infection of the central nervous system (CNS), granulomatous amebic encephalitis (GAE) in humans. GAE cases are increasingly been reported among immunocompromised patients, with few cases in immunocompetent hosts. Diagnosis of GAE primarily includes neuroimaging, microscopy, cerebrospinal fluid (CSF) culture, histopathology, serology and molecular techniques. Early diagnosis is vital for proper management of infected patients. Combination therapeutic approach has been tried in various GAE cases reported worldwide. We tried to present a comprehensive review, which summarizes on the epidemiology of GAE caused by Acanthamoeba along with the associated clinical symptoms, risk factors, diagnosis and treatment of GAE among infected patients.

Toxoplasmic encephalitis of basal ganglia with tumor-like features proven by pathogen-specific polymerase chain reaction and direct DNA sequencing.

We report a case of a young female patient who developed progressive neurological dysfunction with a ring-enhancing tumor-like nodule on brain magnetic resonance imaging. Urgent surgery was performed to remove the mass in the left basal ganglia. Pathological findings showed that the necrotic brain areas were accompanied by congestion, edema, discrete hemorrhage, and intestinal and perivascular lymphohistiocytic infiltration. Immunohistochemical staining results showed that Toxoplasma gondii (T. gondii) immunoreactivity was detected in both cysts and tachyzoites in these areas. The glycerol-3-phosphate dehydrogenase gene (B1) of T. gondii was amplified by sequence-specific polymerase chain reaction (PCR) and the PCR products were bi-directional Sanger sequenced. A 195 bp consensus sequence of the gene B1 was found to be 98% identical to a reference T. gondii sequence (GenBank accession No. kx270373). The final diagnosis was toxoplasmic encephalitis in the left basal ganglia. This report suggests that PCR and bi-directional DNA sequencing of T. gondii gene might be the most convenient and rapid tools for accurate diagnosis of toxoplasmic encephalitis .

Diagnosis of Chagasic Encephalitis by Sequencing of 28S rRNA Gene.

We report a case of chagasic encephalitis diagnosed by 28S rRNA sequencing. The diagnosis of chagasic encephalitis is challenging, given the broad differential diagnosis for central nervous system lesions in immunocompromised patients and low sensitivity of traditional diagnostics. Sequencing should be part of the diagnostic armamentarium for potential chagasic encephalitis.

Immune-mediated encephalitis for the infectious disease specialist.

PURPOSE OF REVIEW: Autoimmune encephalitis is increasingly recognized and must be distinguished from infectious forms of encephalitis. Moreover, physicians should be aware of infectious triggers of autoimmune encephalitis and of infectious complications associated with treatment. RECENT FINDINGS: Recent epidemiological studies suggest that the incidence of autoimmune encephalitis may rival that of infectious encephalitis. Although distinguishing autoimmune from infectious forms of encephalitis on clinical grounds can be challenging, recently proposed diagnostic criteria can provide some assistance. There has been an explosion in our knowledge of autoimmune encephalitis associated with antibodies to neuronal cell surface antigens, and two of the most common forms, anti-NMDA receptor encephalitis and anti-LGI1 encephalitis, are typically associated with distinctive clinical features. Although tumors have long been known to trigger autoimmune encephalitis, it has been recently recognized that herpes simplex encephalitis may trigger the generation of antineuronal autoantibodies resulting in an autoimmune neurologic relapse. Both first and second-line therapies for autoimmune encephalitis are associated with infectious complications, whereas emerging treatments, including anakinra and tocilizumab, may also result in increased susceptibility to certain infections. SUMMARY: The diagnosis and management of autoimmune encephalitis is complex, and awareness of diagnostic criteria and modalities, typical clinical syndromes, infectious triggers of disease, and infectious complications of therapies is critical in optimizing care for affected patients.

An Improved Specimen Handling Procedure for Pathogen Detection of the Cerebrospinal Fluid by Microscope.

BACKGROUND: In order to increase the detection rate of pathogenic microorganisms in CSF, an improved specimen handling procedure (ISHP) was created. METHODS: This study enrolled encephalitis and control groups, both groups were handled with traditional specimen handling procedure (TSHP) and ISHP. Glutaraldehyde was added to the ISHP. Observed items included: total protein, glucose, chloride, adenosine deaminase, lactate dehydrogenase, sediment, cell and pathogen, Pandy's test. RESULTS: Sediment test of CSF: There was 1 specimen in 10 control specimens tested by TSHP in which Pandy's test was positive; there were 2 specimens tested by ISHP which could see sediment by eye. There was no statistical difference between those two methods (p = 1.000, Table 1). Ten specimens in 23 of the encephalitis group processed by TSHP were positive with Pandy's test; 23 specimens processed by ISHP could all see sediments by eye (Figure 1). There was a statistical difference between the two methods (p = 0.000, Table 1). Pathogen test of CSF: no pathogen was found in the control group processed by TSHP and ISHP. No pathogen was found in the encephalitis group specimens processed by TSHP. Pathogen tests were positive in 7 encephalitis specimens processed by ISHP (p = 0.009, Table 1), which were confirmed as Rickettsia spp. by Gimenze stain (Figure 1B), IFA (Figure 2). CONCLUSIONS: The results revealed that ISHP contributes to the separation of cells, pathogens (such as Rickettsia), and proteins.

Granulomatous amebic encephalitis caused by Acanthamoeba in an immuncompetent child.

Sütçü M, Aktürk H, Gülümser-Sisko S, Acar M, Erol OB, Somer A, Bilgiç B, Salman N. Granulomatous amebic encephalitis caused by Acanthamoeba in an immuncompetent child. Turk J Pediatr 2018; 60: 340-343. Acanthamoeba may lead to granulomatous amebic encephalitis (GAE) with high mortality rates generally in patients with immunosupression and/or chronic disease. Here, we present a rare GAE case, who was a previously healthy child. A Georgian 9 year old boy presented with focal seizure on his left arm and confusion. Since computed tomography (CT) demonstrated hypodense lesion on right occipital lobe, brain biopsy was performed. Histopathological examination of the biopsy material revealed Acanthamoeba cysts and trophozoites together with granulomatous inflammation. The patient, who had no clinical and laboratory findings consistent with immunedeficiency, was diagnosed as GAE. He was treated with a combination drug therapy. Even if it is very rare, amebic meningoencephalitis may also be seen in immunocompetent children, as in our case. Definitive diagnosis is made by microbiological and histopathological examination of brain biopsy material.

Meningoencefalitis: etiología infecciosa en pacientes pediátricos de un hospital de referencia / Meningoencephalitis: infectious etiology in pediatric patients at a reference hospital

Resumen Introducción: Las causas de meningoencefalitis, meningitis o encefalitis pueden ser infecciosas o no infecciosas. Para el diagnóstico microbiológico se requieren cultivos y pruebas moleculares. El objetivo del estudio fue describir las causas infecciosas de meningoencefalitis y su presentación clínica. Métodos: Estudio transversal realizado en el Hospital Civil de Guadalajara Dr. Juan I. Menchaca. Se incluyeron pacientes mayores de 28 días de vida con síndrome de meningitis, encefalitis o meningoencefalitis. Se identificó la etiología infecciosa mediante cultivos, tinciones de Gram y pruebas moleculares de líquido cefalorraquídeo. Se compararon las características de pacientes con y sin diagnóstico etiológico. Resultados: Se incluyeron en el estudio 50 pacientes con meningoencefalitis (n = 25), meningitis (n = 19) o encefalitis (n = 6). La mediana de edad fue de un año y el 62% de los pacientes fueron de sexo masculino. Se realizó diagnóstico etiológico infeccioso en el 42%: el 65.2% (n = 15) se debió a virus y el 34.8% (n = 8) a bacterias. En los pacientes con diagnóstico etiológico, se presentó un mayor número de leucocitos en líquido cefalorraquídeo (92 leu/mm3 vs. 12 leu/mm3, p = 0.001). Fue más frecuente el antecedente de gastroenteritis (razón de momios [RM]: 3.5; intervalo de confianza al 95% [IC 95%]: 1.007-12.1; p = 0.04) y ante la exploración, fue más frecuente la rigidez de cuello (RM: 3.8; IC 95%: 1-15.2; p = 0.04). Conclusiones: El 42% de los pacientes con meningitis, encefalitis o meningoencefalitis tuvieron diagnóstico etiológico infeccioso. La causa más frecuente fue el enterovirus.

Abstract Background: The etiologies of meningoencephalitis, meningitis or encephalitis may be infectious or non-infectious. For the microbiological diagnosis it is necessary to perform cultures and molecular tests. The objective of this study was to describe the infectious causes of meningoencephalitis and their clinical presentation. Methods: Cross-sectional study performed at the Hospital Civil de Guadalajara Dr. Juan I. Menchaca. Patients older than 28 days of life with meningitis, encephalitis or meningoencephalitis syndrome were included in the study. Infectious etiology was identified through cultures, Gram stains, and molecular tests of cerebrospinal fluid. The characteristics of patients with and without etiological diagnosis were compared. Results: Fifty patients with meningoencephalitis (n = 25), meningitis (n = 19) or encephalitis (n = 6) were included in the study. The mean age was one year and 62% were male. An infectious etiological diagnosis was performed in 42%; 65.2 % (n = 15) were viruses and 34.8% (n = 8) bacteria. In patients with etiological diagnosis, a higher number of leukocytes were found in cerebrospinal fluid (92 leu/mm3 vs. 12 leu/mm3, p = 0.001); the history of gastroenteritis was more frequent (odds ratio [OR]: 3.5; 95% confidence interval (CI): 1.007-12.1; p = 0.04) and upon examination, neck stiffness was more common (OR: 3.8; 95% CI: 1-15.2; p = 0.04). Conclusions: 42 % of the patients with meningitis, encephalitis or meningoencephalitis had an infectious etiological diagnosis; the most frequent cause was enterovirus.

A case report of granulomatous amoebic encephalitis by Group 1 Acanthamoeba genotype T18 diagnosed by the combination of morphological examination and genetic analysis.

BACKGROUND: The diagnosis of granulomatous amoebic encephalitis is challenging for clinicians because it is a rare and lethal disease. Previous reports have indicated that Acanthamoeba with some specific genotypes tend to cause the majority of human infections. We report a case of granulomatous amoebic encephalitis caused by Acanthamoeba spp. with genotype T18 in an immunodeficient patient in Japan after allogenic bone marrow transplantation, along with the morphological characteristics and genetic analysis. CASE PRESENTATION: A 52-year old man, who had undergone allogenic bone marrow transplantation, suffered from rapid-growing brain masses in addition to pneumonia and died within 1 month from the onset of the symptoms including fever, headache and disorientation. Infection with Acanthamoeba in the brain and lung was confirmed by histological evaluation; immunohistochemical staining and polymerase chain reaction analysis using autopsy samples also indicated the growth of Acanthamoeba in the brain. Gene sequence analysis indicated that this is the second documented case of infection with Acanthamoeba spp. with genotype T18 in a human host. Postmortem retrospective evaluation of cerebrospinal fluid sample in our case, as well as literature review, indicated that some cases of granulomatous amoebic encephalitis caused by Acanthamoeba may be diagnosable by cerebrospinal fluid examination. CONCLUSION: This case indicates that Acanthamoeba spp. with genotype T18 can also be an important opportunistic pathogen. For pathologists as well as physicians, increased awareness of granulomatous amoebic encephalitis is important for improving the poor prognosis along with the attempt to early diagnosis with cerebrospinal fluid.

Brainstem encephalitis. A diagnostic dilemma.

Brainstem encephalitis (BE) is a rare, severe, and potentially life-threatening inflammation of the central nervous system. Brainstem encephalitis has multiple etiologies, which vary in treatment and outcomes. The current literature is generally focused on the infectious causes of BE, while little is known about the other entities, including cases with inconclusive diagnoses. Additionally, the outcomes of BE are not well documented. We present a case of an 18-year-old male who presented with progressive symptoms of brainstem involvement. His clinical investigations, including cerebrospinal fluid (CSF) analysis, were normal; magnetic resonance imaging (MRI) of the brain showed an enhancing medullary lesion, while tissue biopsy yielded no specific diagnosis. Multiple empirical treatments to address possible autoimmune and infectious processes were started with no significant improvement. He continued to deteriorate over a period of 12 weeks. Thereafter, following intensive supportive and rehabilitative care, he started to show slow signs of improvement.

Multiple cortical brain abscesses due to Listeria monocytogenes in an immunocompetent patient.

Listeria monocytogenes is an intracellular organism which is well recognised for its ability to cause meningeal infections in neonates, immunosuppressed, debilitated and elderly individuals. 1 Other less common central nervous system (CNS) infections caused by Listeria spp. include rhomboencephalitis, cerebritis and abscesses in the brain, brain stem and spinal cord. The neuroradiological appearance of Listeria brain abscesses is similar to other types and may also mimic primary or metastatic brain tumours. 2 , 3 We report a case of Listeria brain abscesses in a patient who was being treated for atypical parkinsonism. A good clinical outcome was achieved after appropriate antimicrobial therapy.