Acute bilateral striatal necrosis associated with Mycoplasma pneumoniae infection

Acute Movement Disorders in Childhood

Acute-onset movement disorders (MDs) are an increasingly recognized neurological emergency in both adults and children. The spectrum of possible causes is wide, and diagnostic work-up is challenging. In their acute presentation, MDs may represent the prominent symptom or an important diagnostic clue in a broader constellation of neurological and extraneurological signs. The diagnostic approach relies on the definition of the overall clinical syndrome and on the recognition of the prominent MD phenomenology. The recognition of the underlying disorder is crucial since many causes are treatable. In this review, we summarize common and uncommon causes of acute-onset movement disorders, focusing on clinical presentation and appropriate diagnostic investigations. Both acquired (immune-mediated, infectious, vascular, toxic, metabolic) and genetic disorders causing acute MDs are reviewed, in order to provide a useful clinician’s guide to this expanding field of pediatric neurology.

Autoimmune Movement Disorders in Children

Over the last decade, there have been significant advances in the identification, characterization, and treatment of autoimmune neurologic disorders in children. Many of these diseases include a typical movement disorder that can be a powerful aid to diagnosis. Frequently, movement disorders in autoimmune conditions are the sole or among a few presenting symptoms, allowing for earlier diagnosis of an underlying malignancy or systemic autoimmune disease. Given that early detection and treatment with immunotherapy may confer improved outcomes, recognizing these patterns of abnormal movements is essential for child neurologists. The purpose of this review is to summarize the clinical characteristics, diagnosis, and treatment of movement disorders that occur in pediatric autoimmune disorders.

Cytokine Production by Mononuclear Cells from Patients with Familial Infantile Bilateral Striatal Necrosis

Prompted by findings suggesting immune instability in infantile bilateral striatal necrosis (IBSN), we evaluated levels of proinflammatory (tumor necrosis factor α, interleukin [IL]-1β, IL-6, interferon [IFN]γ) and anti-inflammatory (IL-10 and IL-1ra) cytokines produced by peripheral blood mononuclear cells (PBMC) from 6 children with IBSN and 11 age-matched controls. Compared to controls, non-stimulated PBMC from the IBSN group produced a significantly lower level of IL-1ra (by 38%; p < 0.001) and significantly lower levels of TNFα, IL-1β, and IFNγ (by 36% [p < 0.001], 25% [p = 0.06], and 32% [p < 0.02]) under PBMC stimulation. The severe cachexia manifesting shortly after IBSN onset may impair the immunological state, placing patients at risk of death from hyperpyrexia and sepsis.

Neurological Disorders Associated with Striatal Lesions: Classification and Diagnostic Approach

Neostriatal abnormalities can be observed in a very large number of neurological conditions clinically dominated by the presence of movement disorders. The neuroradiological picture in some cases has been described as "bilateral striatal necrosis" (BSN). BSN represents a condition histo-pathologically defined by the involvement of the neostriata and characterized by initial swelling of putamina and caudates followed by degeneration and cellular necrosis. After the first description in 1975, numerous acquired and hereditary conditions have been associated with the presence of BSN. At the same time, a large number of disorders involving neostriata have been described as BSN, in some cases irrespective of the presence of signs of cavitation on MRI. As a consequence, the etiological spectrum and the nosographic boundaries of the syndrome have progressively become less clear. In this study, we review the clinical and radiological features of the conditions associated with MRI evidence of bilateral striatal lesions. Based on MRI findings, we have distinguished two groups of disorders: BSN and other neostriatal lesions (SL). This distinction is extremely helpful in narrowing the differential diagnosis to a small group of known conditions. The clinical picture and complementary exams will finally lead to the diagnosis. We provide an update on the etiological spectrum of BSN and propose a diagnostic flowchart for clinicians.

Transient parkinsonism following mycoplasma pneumoniae infection with normal brain magnetic resonance imaging (MRI)

Parkinsonism caused by infection is uncommon in children. We report 2 previously healthy children with acute self-limiting parkinsonism following Mycoplasma pneumoniae infection, with normal brain magnetic resonance imaging (MRI). Our case report expands the phenotype of parkinsonism associated with M. pneumoniae infection. We recommend that children with acute parkinsonism preceded by a period of febrile illness, even with a normal brain MRI, should be investigated for M. pneumoniae infection.

Reversible parainfectious bilateral "striatal necrosis"

Bilateral striatal necrosis is usually associated with either endogenous or exogenous toxins, and with poor neurodevelopmental outcomes. We describe two patients with acute bilateral striatal clinical syndrome and magnetic resonance signal changes who made a complete clinical and radiologic recovery within 3 months. After an uneventful pregnancy, normal birth, and normal development, both boys presented at ages 3 and 5 years, respectively, after a viral illness with slurring of speech, bradykinesia, and an extrapyramidal movement disorder. On examination, both manifested bilateral cog wheel rigidity, with a broad-based gait and flexor plantar response. Cranial magnetic resonance imaging in both children indicated bilateral, symmetric, high signal changes in the lentiform nucleus, predominately in the putamen, with sparing of the globus pallidi bilaterally. The brain parenchyma was otherwise normal. Neurometabolic investigations produced normal results in both patients. The pathogenesis is uncertain, but could be immune-mediated. Both children, at 3-year and 1-year follow-ups, respectively, are doing well neurologically and academically. Our patients demonstrate that abnormal imaging findings during acute stages do not preclude good clinical and radiologic recovery.

Acute infantile bilateral striatal necrosis: single-photon emission computed tomography (SPECT) imaging and review

Acute infantile bilateral striatal necrosis is a rarely described acute neurological syndrome associated with radiological findings. Its etiology and pathogenic mechanisms are unknown. Clinically, the syndrome usually follows respiratory illnesses and presents with an array of neurological findings, including axial ataxia, grimacing, mutism, head nodding, and high-pitched cry. This study follows a child with acute infantile bilateral striatal necrosis both clinically and radiologically. In addition, for the first time, the authors describe the serial findings of single-photon emission computed tomography (SPECT) from onset of illness through 20 months. Their findings indicate an initial insult apparent on both magnetic resonance imaging and SPECT localized to the basal ganglia, which, although improved over time, does not fully regress. The residual lesion on SPECT was clinically associated with only mild attention deficit disorder and no motor pathology. The authors review the published literature concerning acute infantile bilateral striatal necrosis and suggest possible mechanisms of this poorly understood and probably underreported condition.

Infantile bilateral striatal necrosis associated with human herpes virus-6 (HHV-6) infection

A 1-year-old female with acute bilateral striatal necrosis secondary to exanthema subitum associated with human herpesvirus 6 (HHV-6) infection is reported. The patient was previously healthy. She presented with progressive neurologic signs of oral dyskinesia and involuntary movements, after suffering from exanthema subitum. Initial magnetic resonance imaging (MRI) demonstrated abnormal signals in the bilateral striatal regions. In addition, the serum HHV-6 IgM class antibody level was significantly increased. The patient is thought to be the first case of HHV-6 infection related infantile bilateral striatal necrosis (IBSN).

Central nervous system manifestations of Mycoplasma pneumoniae infections

Mycoplasma pneumoniae infection is associated with several manifestations from the central nervous system (CNS) such as encephalitis, aseptic meningitis, acute transverse myelitis, stroke, and polyradiculopathy. In the current paper epidemiologic, clinical, laboratory and treatment data on these manifestations are reviewed. The M. pneumoniae induced immune dysregulation and its contributing role in the pathogenesis of neurological insult is discussed. The recent introduction in clinical practice of newer molecular diagnostic techniques has helped in establishing a firmer association between M. pneumoniae infection and CNS disease especially encephalitis. Clinicians should be aware of the potential association between M. pneumoniae infection and several CNS manifestations. The role of various anti-microbial or immunomodulating therapies in treating such manifestations should be further explored.

Biotin-responsive basal ganglia disease maps to 2q36.3 and is due to mutations in SLC19A3

Biotin-responsive basal ganglia disease (BBGD) is a recessive disorder with childhood onset that presents as a subacute encephalopathy, with confusion, dysarthria, and dysphagia, and that progresses to severe cogwheel rigidity, dystonia, quadriparesis, and eventual death, if left untreated. BBGD symptoms disappear within a few days with the administration of high doses of biotin (5-10 mg/kg/d). On brain magnetic resonance imaging examination, patients display central bilateral necrosis in the head of the caudate, with complete or partial involvement of the putamen. All patients diagnosed to date are of Saudi, Syrian, or Yemeni ancestry, and all have consanguineous parents. Using linkage analysis in four families, we mapped the genetic defect near marker D2S2158 in 2q36.3 (LOD=5.9; theta=0.0) to a minimum candidate region (approximately 2 Mb) between D2S2354 and D2S1256, on the basis of complete homozygosity. In this segment, each family displayed one of two different missense mutations that altered the coding sequence of SLC19A3, the gene for a transporter related to the reduced-folate (encoded by SLC19A1) and thiamin (encoded by SLC19A2) transporters.

Mycoplasma pneumoniae infection and Tourette's syndrome

An association between infection and Tourette's syndrome (TS) has been described repeatedly. A role for streptococcal infection (PANDAS) has been established for several years, but the involvement of other infectious agents such as Borrelia Burgdorferi or Mycoplasma pneumoniae has only been described in single case reports. We examined antibody titers against M. pneumoniae and various types of antibodies by immunoblot in patients and in a sex- and age-matched comparison group. Participants comprised 29 TS patients and 29 controls. Antibody titers against M. pneumoniae were determined by microparticle agglutination (MAG) assay and confirmed by immunoblot. Elevated titers were found in significantly more TS patients than controls (17 vs. 1). Additionally, the number of IgA positive patients was significantly higher in the TS group than in the control group (9 vs. 1). A higher proportion of increased serum titers and especially of IgA antibodies suggests a role for M. pneumoniae in a subgroup of patients with TS and supports the finding of case reports implicating an acute or chronic infection with M. pneumoniae as one etiological agent for tics. An autoimmune reaction, however, has to be taken into account. In predisposed persons, infection with various agents including M. pneumoniae should be considered as at least an aggravating factor in TS.

Diagnosis, treatment, and prognosis of Mycoplasma pneumoniae childhood encephalitis: systematic review of 58 cases

Most of the knowledge on Mycoplasma pneumoniae encephalitis in children is based on case reports or small case series. The aim of this study was to assess the important features of the disease by a systematic review of previously published cases. Overall, 58 cases (22 female, 36 male; median age 10 years, range: 2-17 years), derived from 38 reports, were reviewed. Forty-five patients (76%) had flulike or respiratory symptoms prior to the onset of neurologic disease, and 23 patients (40%) presented with pulmonary infiltrates. Cerebrospinal fluid (CSF) pleocytosis (mostly mononuclear cells) and elevated cerebrospinal fluid protein counts were present in 34 (59%) and 21 (36%) patients, respectively. Cranial computed tomography (CT) or magnetic resonance imaging (MRI) abnormalities were seen in 18 (31%) and 17 (29%) patients, respectively, whereby various different presentations were observed. Forty-four patients (76%) received antimicrobial therapy active against mycoplasmas, most frequently erythromycin (n = 29) or minocycline (n = 6). Only in one patient, cure was directly attributed to antimicrobial therapy (with chloramphenicol) by the respective authors. Thirty-three patients (57%) recovered without sequelae, 20 patients (34%) had minor to major sequelae, and 5 patients (9%) died. A high cerebrospinal fluid cell count, cerebrospinal fluid protein elevation, and higher age were associated with an unfavorable outcome.

Restless legs syndrome: association with streptococcal or mycoplasma infection

Group A beta-hemolytic streptococcal infections have been reported to cause neuropsychiatric symptoms, such as chorea, tics, and obsessive-compulsive disorder, presumably through autoimmune damage to basal ganglia. Mycoplasma pneumoniae infections have also been reported to cause damage to the basal ganglia. Restless legs syndrome is a movement disorder with focal restlessness, an irresistible desire to move, and exacerbation by long periods of sitting or lying. We present three children with transient restless legs syndrome-like symptoms possibly associated with group A beta-hemolytic streptococcal infection or Mycoplasma pneumoniae infection. One of three patients had persistently elevated enzyme-linked immunosorbent optical density values against human caudate and putamen.

Type I glutaric aciduria, part 2: a model of acute striatal necrosis

Type I glutaric aciduria (GA1) is an inborn error of organic acid metabolism that is associated with acute neurological crises, typically precipitated by an infectious illness. The neurological crisis coincides with swelling, metabolic depression, and necrosis of basal ganglia gray matter, especially the putamina and can be visualized as focal, stroke-like, signal hyperintensity on MRI. Here we focus on the stroke-like nature of striatal necrosis and its similarity to brain injury that occurs in infants after hypoxia-ischemia or systemic intoxication with 3-nitropropionic acid (NPA). These conditions share several features including abrupt onset, preferential effect in the striatum and age-specific susceptibility. The pathophysiology of the conditions is reviewed and a model proposed herein. We encourage investigators to test this model in an appropriate experimental system.

Mycoplasma pneumoniae ecephalitis

Mycoplasma pneumoniae causes between 5 and 10 percent of acute childhood encephalitis in Europe and North America. Encephalitis due to this organism may be caused by direct infection of the brain, immune-mediated brain injury or thromboembolic phenomenon. The prognosis is guarded with 20 to 60 percent suffering neurologic sequelae. The diagnosis of M. pneumoniae encephalitis should be based on strong evidence of M. pneumoniae infection that includes detection of the organism in culture or using molecular detection techniques in addition to serology and exclusion of other potential etiologies. Antibiotic therapy should be considered for all children with suspected M. pneumoniae encephalitis; antibiotics with good central nervous system (CNS) penetration such as ciprofloxacin, doxycycline, chloramphenicol or azithromycin are appropriate under most circumstances. Immune modulating therapies, such as corticosteroids, intravenous immune globulin or plasmapharesis, should be considered in those with immune-mediated syndromes such as acute disseminated encephalomyelitis.

Treatment of dystonia in striatal necrosis caused by Mycoplasma pneumoniae

We report on an 8-year-old male with bilateral striatal necrosis secondary to Mycoplasma pneumoniae respiratory infection. This patient has been remarkable for persistent severe dystonia that has been difficult to treat. We share our experience of beneficial responses to multimodal treatment, including moderate doses of trihexyphenidyl, botulinum toxin, and intrathecal baclofen.

Brainstem and striatal encephalitis complicating Mycoplasma pneumoniae pneumonia: possible benefit of intravenous immunoglobulin

Encephalitides of the brainstem and the striatum associated with Mycoplasma pneumoniae infection are believed to be mediated by an autoimmune process triggered by the organism, a toxin or direct invasion by the organism itself. Inability to identify M. pneumoniae from cerebrospinal fluid by culture or polymerase chain reaction suggested a possible immunologic process. A trial of intravenous immunoglobulin in a critically ill patient with encephalitis that developed in parallel to M. pneumoniae pneumonia was associated with neurologic improvement within 48 h of treatment.