Extremely elevated cerebrospinal fluid protein levels in a child with neurologic symptoms: Beware of haemophagocytic lymphohistiocytosis

Neurologic symptoms can be the initial manifestation of haemophagocytic lymphohistiocytosis (HLH). In this case study, we present a 3-year old boy with a clinical picture of encephalitis, a cerebrospinal fluid (CSF) protein level up to 1165 mg/dl and diffuse cerebral MRI abnormalities. The diagnosis of HLH was established only 6 weeks after initial presentation. The boy recovered after HLH therapy with persisting mild cognitive defects. Genetic investigation demonstrated X-linked lymphoproliferative disease (XLP) as the underlying cause of HLH. The extremely elevated protein level in CSF in this case has not yet been reported in patients with HLH.     

Hypoxic-ischaemic encephalopathy: early and late magnetic resonance imaging findings in relation to outcome.

Sixteen infants with hypoxic-ischaemic encephalopathy (HIE) were studied using serial magnetic resonance imaging (MRI) up to the age of 2 years. The infants had regular neurological and developmental assessments. An nuclear magnetic resonance (NMR) score was devised to quantify the early and late MRI findings and a neurological optimality score was used to quantify abnormal neurological signs at the time of the final examination. The follow up MRI score was compared with the neonatal MRI score and the outcome of the child. There was a strong positive correlation between the neonatal and follow up MRI scores and between MRI scores and optimality score. All infants with a normal outcome had patchy white matter abnormalities. All infants with an abnormal outcome had extensive white matter abnormalities. The outcome was most severe in those infants with additional basal ganglia atrophy with or without cyst formation. Infants with mild HIE who are developmentally normal at the age of 2 years do not have normal MRI scans and may be at risk of minor neurological problems by school age. Bilateral basal ganglia abnormalities are associated with severe developmental delay, but infants with mainly white matter and cortical abnormalities have less severe problems despite extensive tissue loss.     

Chlamydia pneumoniae infection-related hemophagocytic lymphohistiocytosis and acute encephalitis and poliomyelitis-like flaccid paralysis

A 3-year-old male presented with Chlamydia pneumoniae infection-related hemophagocytic lymphohistiocytosis (HLH). The patient developed an episode of HLH with severe skin eruption following C. pneumoniae pneumonia. Symptoms responded to steroid/cyclosporine A therapy, but the patient slowly lost consciousness and developed systemic flaccid paralysis. He was diagnosed with encephalitis/myelitis by brain and spinal MRI. Neurological symptoms and signs gradually resolved. We thought that the immune response to C. pneumoniae infection triggered the development of HLH, associated with unusual neurological complications. This report describes a novel case of C. pneumoniae-associated HLH and with poliomyelitis like flaccid paralysis.     

儿童噬血细胞淋巴组织细胞增生症20例分析

目的了解噬血细胞淋巴组织细胞增生症(HLH)的病因,临床特点,治疗及预后。方法回顾性分析20例HLH患儿的发病相关因素,临床特点,实验室检查指标的变化,治疗效果以及转归。结果所有病例均以持续高热起病,均有肝脾肿大,50%患儿有淋巴结肿大;所有患儿二系以上外周血细胞减少,肝功能异常,凝血功能异常有17例(85%),高甘油三脂血症15例(75%),血清铁蛋白增高13例(65%)。17例(85%)骨髓涂片可见组织细胞增生。12例(60%)和感染因素相关,其中8例(40%)明确与EB病毒感染有关。有6例(3%)按HLH-2004方案正规化疗,达到临床治愈。14例(70%)不规范化疗患儿,8例(40%)仍有肝功能异常和体温波动,5例(25%)死亡。结论HLH起病急重,进展快,病死率高。有明显血象、骨髓细胞学、肝功能改变,高甘油三酯血症以及血清铁蛋白改变。对高度怀疑为HLH的患儿,应及早行诊断性治疗,规范按照HLH-2004方案化疗,改善预后。     

Magnetic resonance imaging of the brain in adenylosuccinate lyase deficiency: a report of seven cases and a review of the literature

Adenylosuccinate lyase (ADSL) deficiency is a rare autosomal recessive disorder of purine metabolism. Patients may present with a wide range of neurological symptoms. Head imaging abnormalities have been reported only rarely in the scientific literature and include atrophy of the cerebral cortex, corpus callosum, cerebellar vermis, lack of myelination, delayed myelination, anomalies of the white matter, and lissencephaly. The pathogenesis of abnormalities remains unknown. To further the understanding of the spectrum of brain abnormalities associated with ADSL deficiency, we examined the magnetic resonance findings in seven Polish patients with different clinical phenotypes and genotypes. Head MRI showed impaired white matter myelination with various degrees of global supra- and infratentorial white matter loss including widening of the lateral ventricles, enlargement of the subarachnoid spaces, atrophy of the cerebrum, hypoplasia of the cerebellar hemispheres and enlargement of the cisterna magna, and white matter abnormal hyperintense signal on T₂-weighted sequences. We recommend performing a detailed analysis of urine and plasma purine metabolites in patients who have neurological findings, including developmental delay, microcephaly, autistic features, neonatal encephalopathy, and seizures especially if MRI findings such as delayed or lack of myelination, white matter abnormal signal, and atrophy of the cerebrum and/or cerebellum are also present. Greater awareness of adenylosuccinate lyase deficiency among general pediatricians, neonatologists, pediatric neurologists, and also radiologists is the key to identifying the disorder at an early stage.     

Diffusion tensor imaging in infants with basal ganglia-thalamic lesions.

We performed diffusion tensor imaging in two infants with neonatal hypoxic-ischemic encephalopathy. MRI revealed basal ganglia-thalamic lesions in both patients during the neonatal period. Patient 1 had severe neurological sequelae, whereas patient 2 achieved normal development. Conventional MRI at 12 months of age showed abnormal high-intensity areas in bilateral basal ganglia and thalami in patient 1, whereas no abnormal intensities were recognized in patient 2. Diffusion tensor tractography demonstrated poor depiction of white matter tracts above the level of centrum semiovale in patient 1. Region of interest analysis showed that fractional anisotropy of white matter of centrum semiovale and deep white matter was markedly reduced in patient 1 compared with patient 2, although apparent diffusion coefficient was not largely different between them. Our study suggested that abnormalities of diffusion property will be more widely present than those of conventional MRI. Diffusion tensor imaging will be useful to detect white matter abnormalities in normal-appearing white matter on conventional MRI.     

Clinical characteristics of children with cerebral white matter abnormalities.

The rapidly expanding use of magnetic resonance imaging (MRI) in children with neurological impairments of unknown aetiology has revealed a large number of children with abnormalities of the cerebral white matter, some with leukodystrophy-like white matter abnormalities on MRI, but non-progressive in clinical presentation and course. The aim of this study was to investigate the clinical and neuroradiological characteristics of 26 children with white matter abnormalities of unknown origin and to find diagnostic clues or indicators of progressive versus nonprogressive disease. The typical child with white matter abnormalities was characterized by onset of symptoms within the first year of life, most often presenting as general developmental delay and hypotonia. Later-appearing signs were spasticity and ataxia and as a rule severe learning and motor disabilities. Serious ophthalmological signs were frequently seen. Perinatal adverse events were rare, infectious aetiologies not indicated but prenatal stigmata relatively common. The clinical course was progressive in 11 children and non-progressive in 15. Late onset presentation was associated with a progressive course whereas prenatal stigmata and asymmetrical white matter lesions only were found in children with a non-progressive disorder. The MRI showed three main patterns: a) a generalized increase of the T2 signal of the white matter in 12 children, b) a bilateral, symmetric but not generalized abnormality in nine and c) asymmetric, focal or multifocal pathology in five. Useful information as to clinical entities and course was obtained from the combined clinical and radiological assessment. A precise nosological diagnosis could be made in six cases. The study showed that white matter abnormalities in children constitute a heterogeneous group of rare and 'anonymous' conditions, motivating collaborative studies for further clarification of background and management.     

A Diagnostic Dilemma: Similarity of Neuroradiological Findings in Central Nervous System Hemophagocytic Lymphohistiocytosis and Aspergillosis

Central nervous system (CNS) involvement in the context of hemophagocytic lymphohistiocytosis (HLH) is not uncommon. Given the immunosuppressive nature of HLH therapy, infectious complications are also seen. We describe a 9‐year‐old male who developed acute neurological decline secondary to aspergillosis while undergoing HLH therapy. The significant overlap observed in CNS neuroimaging of HLH and aspergillosis and the subtleties that may help differentiate the two are discussed. The importance of obtaining tissue for definitive diagnosis is underscored.     

Incidence and treatment of hemophagocytic lymphohistiocytosis in hospitalized children with Ehrlichia infection

We report a large cohort of pediatric patients with human monocytic ehrlichiosis (HME), enabling an estimated incidence of secondary hemophagocytic lymphohistiocytosis (HLH) in hospitalized children with HME. Among 49 children with PCR‐confirmed Ehrlichia infection, 8 (16%) met current criteria for HLH. Those with HLH had more significant hematologic abnormalities and longer durations from symptom onset to admission and definitive anti‐infective therapy. Among these eight, three received chemotherapy plus doxycycline, one of whom died; the other five were treated with doxycycline without chemotherapy, and all survived without HLH recurrence. Our findings demonstrate that antimicrobial therapy alone can successfully resolve Ehrlichia‐associated HLH.     

Neuroimaging abnormalities in Griscelli's disease

Griscelli's disease is a rare autosomal recessive immunodeficiency syndrome. We report a 7-1/2-month-old white girl who presented with this syndrome, but initially without neurological abnormalities. Initial CT of the brain was normal. Despite haematological remission with chemotherapy, she developed neurological symptoms, progressing to coma. At this time, CT showed areas of coarse calcification in the globi pallidi, left parietal white matter and left brachium pontis. Hypodense areas were present in the genu and posterior limb of the internal capsule on the right side, as well as posterior aspects of both thalami, together with minimal generalised atrophy. MRI revealed areas of increased T2 signal and a focal area of abnormal enhancement in the subcortical white matter. Griscelli's disease should be added to the list of acquired neuroimaging abnormalities in infants.     

Allogeneic hematopoietic stem cell transplantation is associated with cure and durable remission of late‐onset primary isolated central nervous system hemophagocytic lymphohistiocytosis

Primary isolated CNS presentation of HLH is exceedingly rare and typically associated with significant morbidity and mortality. We describe an adolescent patient with late‐onset, primary isolated CNS HLH and a compound heterozygous PRF1 mutation (c50delT (p.L17 fs); c.1229G>C (p.R410P)), not previously reported with this phenotype. He was successfully treated with allogeneic HSCT following a reduced‐intensity conditioning regimen, despite a high pre‐HSCT comorbidity index. Two years after transplant, he is alive and in disease remission. While patients with systemic HLH and active CNS disease have relatively poorer outcomes, a high index of suspicion may aid with early diagnosis of primary isolated CNS HLH; prompt treatment with HSCT may be associated with improved cure and durable remission of this rare disease.     

Traumatic head injury mimicking acute encephalopathy with biphasic seizures and late reduced diffusion

Many studies have reported acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) associated with viral infection at onset, but few studies have reported AESD without infection. We report the case of a 9‐month‐old boy who had a clinical course mimicking AESD after a traffic accident. The traffic accident caused a mild subdural hematoma without neurological abnormalities on admission. The boy became unconscious on the second day, and he was diagnosed with non‐convulsive status epilepticus on the third day. Diffusion‐weighted imaging showed reduced water diffusion in the subcortical white matter. On laboratory analysis interleukin (IL)‐6 was elevated in the cerebrospinal fluid (CSF), but not in the serum. He had severe neurological sequelae with mental retardation, spastic tetraplegia, and epilepsy. We suggest that brain damage mimicking AESD was caused by the traffic accident and the prolonged seizure during infancy.     

Multiple sclerosis presenting at 4 years of age: clinical and MRI correlations

The authors present a patient with multiple sclerosis (MS) whose onset of illness was at 4 years of age. Three separate and distinct episodes of central nervous system (CNS) dysfunction associated with cerebrospinal fluid (CSF) pleocytosis, electroencephalographic (EEG) abnormalities, and extensive CNS white matter demyelination on both computerized tomography (CT) and magnetic resonance imaging (MRI) characterized her clinical course. Two episodes responded well to prednisone therapy.     

Neurotoxicity Due to CNS Therapy for Leukemia

CNS symptoms ranging from mild to lethal have occurred following CNS radiotherapy and intrathecal chemotherapy. Cranial radiotherapy often produces signs of mild encephalopathy, with predominance of somnolence. In rare cases, it appears that CNS radiotherapy may be followed by progressive encephalopathy. Intrathecal methotrexate frequently causes symptoms of meningeal irritation. Occasionally cases of weakness and paralysis, and rare instances of severe encephalopathy, may occur. However, in leukemic children treated with intensive chemotherapy and CNS radiotherapy who develop neurological complications, it is often difficult to determine which of many possible factors may be causing the CNS symptoms. The pathogenesis of the various forms of methotrexate neurotoxicity is poorly understood. The best-established cause for these symptoms is high concentrations of methotrexate in the CSF or prolonged exposure of the brain to low CSF concentrations of methotrexate. These elevated concentrations of the drug may in turn be due to impaired elimination of the drug from the cerebrospinal fluid (usually due to overt CNS leukemia) or to increased dosage in relation to cerebrospinal fluid volume (due to adolescent age). Leukoencephalopathy is occasionally found at autopsy in children given intensive therapy with CNS radiotherapy and intrathecal methotrexate, together with intensive systemic chemotherapy. It was proposed that alteration of the blood-brain barrier by cranial radiotherapy allows systemically administered anti-leukemic drugs to enter the brain and to cause necrotic changes in the CNS white matter. Leukoencephalopathy also occurs following intraventricular administration of methotrexate. CNS-toxicity due to intrathecal cytosine arabinoside is clinically similar to the symptoms seen following intrathecal methotrexate.     

Neurological outcome in adult patients with early-treated phenylketonuria

Due to the observation of severe neurological symptoms in single patients as well as brain imaging, neuropsychological and neurophysiological abnormalities, the long-term prognosis of treated phenylketonuria is still under discussion. We investigated the neurological outcome of 57 (24 male, 33 female) patients with phenylketonuria (diet onset <3 months) at a mean age of 23.6 (17–33) years in comparison to control subjects. Methods used were a clinical-neurological examination, tests for fine motor abilities, IQ test (WAIS-R), a neuropsychological attention task and MRI (30 patients only). Tremor was increased in the patients (28%) compared to controls (15%). Fine motor abilities were significantly reduced in three areas: hand-wrist steadiness, finger-hand dexterity and hand-wrist speed. Tremor as well as reduced fine motor skills were not associated with treatment-related variables, e.g. diet onset, strictness of biochemical control or amount of MRI white matter change. IQ was lower in patients (mean 97.6) compared to matched control subjects (mean 105.5). IQ at 12 years was correlated with biochemical control from birth up to the age of 12 and remained stable up to adult age, independent of biochemical control after 12 years of age. In contrast to the other outcome parameters, the performance in a neuropsychological attention task was influenced by the concurrent plasma phenylalanine concentration. Specific late-onset neurological impairment was not identified in this sample of early-treated adults with phenylketonuria. Conclusion Careful neurological investigation revealed subtle symptoms of brain damage even after early-initiated treatment in adult patients with phenylketonuria. At present it cannot be excluded that further neurological deterioration could emerge later in life. Thus, patients with phenylketonuria – either on or off diet – should be monitored throughout life. Received: 5 February 1998 / Accepted in revised form: 22 June 1998     

Ophthalmological abnormalities in children with cerebral white matter disorders.

The use of magnetic resonance imaging (MRI) in children with severe neurological impairment has defined a subgroup with increased T2-signals from cerebral white matter. The causes of white matter abnormalities are for the most part unknown, despite extensive investigation. Their clinical correlates and characteristics have still to be systematically analysed and described. We have compared clinical, ophthalmological and electro-ophthalmological findings in such children to delineate neurological and MRI patterns and have sought to correlate with the progression of disease. Clinical and electro-ophthalmological investigations were performed in 26 children with cerebral white matter abnormalities of unknown aetiology; 25 of the 26 children showed abnormalities, 23 clinical and 18 electro-ophthalmological. Optic nerve abnormalities, severe visual impairment and strabismus were the most common. Electro-ophthalmological abnormalities were increased latencies and abnormal waveform of the visual evoked potentials (VEP). Children with progressive disease all had abnormal VEP, whereas none of the ten children with a normal VEP deteriorated. We conclude that children with cerebral white matter abnormalities almost invariably had ophthalmological and often VEP abnormalities. Normal VEP was correlated with non-progressive disorder, as was hypoplasia or malformation of the papilla, whereas abnormal VEP were associated with progressive disease.     

Neurological complications of pandemic influenza A H1N1 2009 infection: European case series and review

Neurological manifestations and outcomes of children with the 2009 H1N1 virus infection have been reported in three American series and from smaller cohorts and case reports worldwide. Of the 83 children admitted between April 2009 and March 2010 with H1N1 virus infection to a tertiary children’s hospital in a European setting, five children aged between 2 and 10 years had neurological symptoms. Four patients had seizures and encephalopathy at presentation. One patient presented with ataxia; one developed neuropsychiatric manifestations, and two developed movement disorders during the disease course. Early neuroimaging showed evidence of acute necrotising encephalopathy (ANE) in one case and non-specific white matter changes in another. Initial neuroimaging was normal for the other three, but interval MRI showed increased signal in bilateral periventricular distribution in one and significant cerebral volume loss in the other. Clinical outcomes varied: two recovered fully while three had residual seizures and/or significant cognitive deficits. Conclusion An analysis of our patients along with all reported cases reveal that seizures and encephalopathy were common neurological presentations associated with pandemic 2009 H1N1 influenza virus infection in children requiring hospital admission. Neuroimaging suggestive of ANE, basal ganglia involvement and volume loss appears to be associated with worse neurological outcome.     

Can neurobehavioral examination predict the presence of cerebral injury in the very low birth weight infant?

This study examined in a regional cohort of 66 term age very low birth weight infants, the relationship between qualitative magnetic resonance imaging (MRI) measures of cerebral white and gray matter abnormalities and infant neurobehavioral functioning assessed by structured neurological examination. The diagnostic utility of the Dubowitz neonatal neurological examination in identifying children with severe cerebral abnormalities was also evaluated. Examination results revealed the presence of high rates of neurological abnormality, with 60% of infants scoring in the suboptimal range relative to infants born full term. Linear associations were found between the severity of structural cerebral abnormality on MRI and the quality of clinically rated infant neurobehavioral functioning, with increasing abnormalities being significantly associated with poorer neurological functioning. In particular, white matter abnormalities were significantly associated with lower mean tone and tone pattern scores and a tendency toward lower mean reflex scores. Gray matter abnormalities were significantly associated with lower tone and tone pattern scores and a tendency toward lower spontaneous movements and orientation/behavior scores. Finally, the Dubowitz Neonatal Neurological Examination was found to have relatively good sensitivity (88%; negative predictive value, 92%) but poor specificity (46%; positive predictive value, 34%) for identifying children with significant MRI abnormalities. Implications of these findings for the neurological evaluation of the very low birth weight infant are discussed.     

Pneumocystis carinii pneumonitis in haemophagocytic lymphohistiocytosis

We report on a 10-y-old boy who developed Pneumocystis carinii pneumonitis (PCP) as the dominant symptom at the onset of haemophagocytic lymphohistiocytosis (HLH). PCP is a common infection in patients with combined primary immunodeficiencies or acquired immunodeficiency syndrome but it has rarely been observed at the onset of HLH. Typically, HLH presents as a febrile syndrome associated with cytopenia and hepatosplenomegaly. Repeated bone marrow aspirates, spleen or lymph node biopsies are sometimes required to reveal haemophagocytosis. Because of the significant immunosuppression during treatment of HLH, prophylaxis of PCP with co-trimoxazole is recommended. However, de-arranged immune response in HLH renders the patients susceptible to opportunistic infections, even before the introduction of immunosuppressants. Conclusion: We suggest that in patients with unclear respiratory symptoms, it is worth considering a differential diagnosis of HLH.     

A syndrome of irreversible leukoencephalopathy following pediatric allogeneic bone marrow transplantation

BACKGROUND: Despite decreases in overall mortality following bone marrow transplantation (BMT), a number of complications such as neurotoxicity have been described and often associated with immunosuppressive agents. The syndrome of reversible posterior leukoencephalopathy has been described in patients receiving cyclosporin and FK-506. We report here a subset of children who developed a syndrome of previously undescribed irreversible leukoencephalopathy following allogeneic BMT. PATIENTS AND METHODS: Between 1996 and 2002, 138 pediatric patients received an allogeneic BMT at Lucile Salter Packard Children's Hospital at Stanford. Six cases of irreversible leukoencephalopathy were observed. Cases were defined as children who exhibited progressive and continued, severe neurologic deterioration lasting greater than 2 weeks and consistent with non-localizing, central nervous system abnormalities. Medical records and magnetic resonance images (MRIs) were reviewed. RESULTS: Median age of the affected patients at BMT was 7.8 years. All six received cyclosporine, and [corrected] one had elevated drug levels. Encephalopathy occurred at a median of 53 days (range 14-77) following BMT. Symptoms at onset of leukoenceophalopathy included confusion and altered mental status, sluggish pupillary responses, abnormal movements, and seizures. Two patients died during their neurologic decline. Four patients remain alive with persistent encephalopathy. MRI showed abnormalities in all patients including periventricular or subcortical white matter involvement in all, and basal ganglia lesions in three. CONCLUSIONS: We report a syndrome of irreversible neurologic deficits and cerebral white matter abnormalities following allogeneic BMT, yet not associated with elevated cyclosporin levels. A precise mechanism for this syndrome is lacking and warrants further consideration.