VP1 is the primary determinant of neuropathogenesis in a mouse model of enterovirus D68 acute flaccid myelitis.

Enterovirus D68 (EV-D68) is an emerging pathogen that can cause severe respiratory and neurologic disease [acute flaccid myelitis (AFM)]. Intramuscular (IM) injection of neonatal Swiss Webster (SW) mice with US/IL/14-18952 (IL52), a clinical isolate from the 2014 EV-D68 epidemic, results in many of the pathogenic features of human AFM, including viral infection of the spinal cord, death of motor neurons, and resultant progressive paralysis. In distinction, CA/14-4231 (CA4231), another clinical isolate from the 2014 EV-D68 outbreak, does not cause paralysis in mice, does not grow in the spinal cord, and does not cause motor neuron loss following IM injection. A panel of chimeric viruses containing sequences from IL52 and CA4231 was used to demonstrate that VP1 is the main determinant of EV-D68 neurovirulence following IM injection of neonatal SW mice. VP1 contains four amino acid differences between IL52 and CA4231. Mutations resulting in substituting these four amino acids (CA4231 residues into the IL52 polyprotein) completely abolished neurovirulence. Conversely, mutations resulting in substituting VP1 IL52 amino acid residues into the CA4231 polyprotein created a virus that induced paralysis to the same degree as IL52. Neurovirulence following infection of neonatal SW mice with parental and chimeric viruses was associated with viral growth in the spinal cord. IMPORTANCE: Emerging viruses allow us to investigate mutations leading to increased disease severity. Enterovirus D68 (EV-D68), once the cause of rare cases of respiratory illness, recently acquired the ability to cause severe respiratory and neurologic disease. Chimeric viruses were used to demonstrate that viral structural protein VP1 determines growth in the spinal cord, motor neuron loss, and paralysis following intramuscular (IM) injection of neonatal Swiss Webster (SW) mice with EV-D68. These results have relevance for predicting the clinical outcome of future EV-D68 epidemics as well as targeting retrograde transport as a potential strategy for treating virus-induced neurologic disease.

Transcription factor EB (TFEB) interaction with RagC is disrupted during enterovirus D68 infection.

Enterovirus D68 (EV-D68) is a picornavirus associated with severe respiratory illness and a paralytic disease called acute flaccid myelitis in infants. Currently, no protective vaccines or antivirals are available to combat this virus. Like other enteroviruses, EV-D68 uses components of the cellular autophagy pathway to rewire membranes for its replication. Here, we show that transcription factor EB (TFEB), the master transcriptional regulator of autophagy and lysosomal biogenesis, is crucial for EV-D68 infection. Knockdown of TFEB attenuated EV-D68 genomic RNA replication but did not impact viral binding or entry into host cells. The 3C protease of EV-D68 cleaves TFEB at the N-terminus at glutamine 60 (Q60) immediately post-peak viral RNA replication, disrupting TFEB-RagC interaction and restricting TFEB transport to the surface of the lysosome. Despite this, TFEB remained mostly cytosolic during EV-D68 infection. Overexpression of a TFEB mutant construct lacking the RagC-binding domain, but not the wild-type construct, blocks autophagy and increases EV-D68 nonlytic release in H1HeLa cells but not in autophagy-defective ATG7 KO H1HeLa cells. Our results identify TFEB as a vital host factor regulating multiple stages of the EV-D68 lifecycle and suggest that TFEB could be a promising target for antiviral development against EV-D68. IMPORTANCE: Enteroviruses are among the most significant causes of human disease. Some enteroviruses are responsible for severe paralytic diseases such as poliomyelitis or acute flaccid myelitis. The latter disease is associated with multiple non-polio enterovirus species, including enterovirus D68 (EV-D68), enterovirus 71, and coxsackievirus B3 (CVB3). Here, we demonstrate that EV-D68 interacts with a host transcription factor, transcription factor EB (TFEB), to promote viral RNA(vRNA) replication and regulate the egress of virions from cells. TFEB was previously implicated in the viral egress of CVB3, and the viral protease 3C cleaves TFEB during infection. Here, we show that EV-D68 3C protease also cleaves TFEB after the peak of vRNA replication. This cleavage disrupts TFEB interaction with the host protein RagC, which changes the localization and regulation of TFEB. TFEB lacking a RagC-binding domain inhibits autophagic flux and promotes virus egress. These mechanistic insights highlight how common host factors affect closely related, medically important viruses differently.

Multimodal Surveillance Model for Enterovirus D68 Respiratory Disease and Acute Flaccid Myelitis among Children in Colorado, USA, 2022.

Surveillance for emerging pathogens is critical for developing early warning systems to guide preparedness efforts for future outbreaks of associated disease. To better define the epidemiology and burden of associated respiratory disease and acute flaccid myelitis (AFM), as well as to provide actionable data for public health interventions, we developed a multimodal surveillance program in Colorado, USA, for enterovirus D68 (EV-D68). Timely local, state, and national public health outreach was possible because prospective syndromic surveillance for AFM and asthma-like respiratory illness, prospective clinical laboratory surveillance for EV-D68 among children hospitalized with respiratory illness, and retrospective wastewater surveillance led to early detection of the 2022 outbreak of EV-D68 among Colorado children. The lessons learned from developing the individual layers of this multimodal surveillance program and how they complemented and informed the other layers of surveillance for EV-D68 and AFM could be applied to other emerging pathogens and their associated diseases.

Longitudinally extensive posterolateral myelitis revealing invasive CNS aspergillosis in an immunocompetent patient.

BACKGROUND: Fungal infections of the central nervous system usually affect immunocompromised patients. Primary Aspergillus myelitis has never been described. REPORT: A 45-year-old immunocompetent male with subacute paraplegia was treated for inflammatory myelitis before clinical deterioration requiring mechanical ventilation. Purulent meningitis preceded the formation of a paraspinal nodule biopsied by neurosurgery. Histopathological analysis revealed the presence of fungal hyphae, and polymerase chain reaction was positive for Aspergillus fumigatus. No cause of immunodeficiency was identified in this patient. DISCUSSION: Primary Aspergillus myelitis may be confused with inflammatory myelitis and should be considered even in the absence of apparent immunosuppression.

Surveillance for Acute Flaccid Myelitis - United States, 2018-2022.

Acute flaccid myelitis (AFM) is a serious neurologic condition primarily affecting children; AFM can cause acute respiratory failure and permanent paralysis. AFM is a rare but known complication of various viral infections, particularly those of enteroviruses (EVs). Increases in AFM cases during 2014, 2016, and 2018 were associated with EV-D68 infection. This report examines trends in confirmed AFM cases during 2018-2022 and patients' clinical and laboratory characteristics. The number of AFM cases was low during 2019-2022 (28-47 cases per year); the number of cases remained low in 2022 despite evidence of increased EV-D68 circulation in the United States. Compared with cases during the most recent peak year (2018), fewer cases during 2019-2021 had upper limb involvement, prodromal respiratory or febrile illness, or cerebrospinal fluid pleocytosis, and more were associated with lower limb involvement. It is unclear why EV-D68 circulation in 2022 was not associated with an increase in AFM cases or when the next increase in AFM cases will occur. Nonetheless, clinicians should continue to suspect AFM in any child with acute flaccid limb weakness, especially those with a recent respiratory or febrile illness.

Patterns of neuromyelitis optica spectrum disorder attacks in different age groups and sexes depending on the status of immunosuppressive therapy: A retrospective cohort study.

BACKGROUND AND PURPOSE: The association between onset age and sex with relapse risk in neuromyelitis optica spectrum disorder (NMOSD) remains inconclusive. We aimed to describe the clinical features of patients with NMOSD in different age groups and sexes and to analyse relapse characteristics pre- and post-immunosuppressive therapy (IST). METHODS: Patients with NMOSD were retrospectively reviewed from our clinical centre's database. Demographic and clinical data, attack presentation, and disease course pre- and post-IST were investigated. We also analysed the effect of onset age on the annualized relapse rate and relapse risk according to sex and IST status. Interactions on the additive scale between onset age and sex were analysed. A restricted cubic spline was used to analyse potential nonlinear correlations. Longitudinal changes in the Expanded Disability Status Scale score across NMOSD attacks were analysed using linear mixed-effect models. RESULTS: In total, 533 patients experienced 1394 attacks pre-IST and 753 relapses post-IST. Older age at onset was correlated with more myelitis attacks but fewer optic neuritis attacks, with no sex-related differences in attack presentation. Pre-IST, relapse risk increased with age at onset in women, while a U-shaped correlation between onset age and relapse risk was found in men. Post-IST, an inverted U-shaped association between the predicted relapse risk and onset age was observed in women. Conversely, a negative correlation between the predicted relapse risk and onset age was found in men. Overall, a higher ratio of myelitis attacks was found post-IST. CONCLUSIONS: Patients of different onset ages and sexes had different relapse patterns before and after IST.

Short segment myelitis as a dominant manifestation of cryptococcal infection: a case report.

Cryptococcal infection of central nervous system commonly involves meningitis or meningoencephalitis, but rarely mimics inflammatory myelitis. We present short segment myelitis as a dominant manifestation caused by Cryptococcus neoformans in a patient with nephrotic syndrome under immunosuppressive therapy. This case report highlights Cryptococcus neoformans as a potential etiological factor for short segment myelitis in immunocompromised hosts.

Combining imaging mass spectrometry and immunohistochemistry to analyse the lipidome of spinal cord inflammation.

Inflammation is a complex process that accompanies many pathologies. Actually, dysregulation of the inflammatory process is behind many autoimmune diseases. Thus, treatment of such pathologies may benefit from in-depth knowledge of the metabolic changes associated with inflammation. Here, we developed a strategy to characterize the lipid fingerprint of inflammation in a mouse model of spinal cord injury. Using lipid imaging mass spectrometry (LIMS), we scanned spinal cord sections from nine animals injected with lysophosphatidylcholine, a chemical model of demyelination. The lesions were demonstrated to be highly heterogeneous, and therefore, comparison with immunofluorescence experiments carried out in the same section scanned by LIMS was required to accurately identify the morphology of the lesion. Following this protocol, three main areas were defined: the lesion core, the peri-lesion, which is the front of the lesion and is rich in infiltrating cells, and the uninvolved tissue. Segmentation of the LIMS experiments allowed us to isolate the lipid fingerprint of each area in a precise way, as demonstrated by the analysis using classification models. A clear difference in lipid signature was observed between the lesion front and the epicentre, where the damage was maximized. This study is a first step to unravel the changes in the lipidome associated with inflammation in the context of diverse pathologies, such as multiple sclerosis.

Diagnostic implications of MOG-IgG detection in sera and cerebrospinal fluids.

The spectrum of MOG-IgG-associated disease (MOGAD) includes optic neuritis (ON), myelitis (MY), acute disseminated encephalomyelitis (ADEM), brainstem encephalitis, cerebral cortical encephalitis (CE) and AQP4-IgG-negative neuromyelitis optica spectrum disorder (NMOSD). In MOGAD, MOG-IgG are usually detected in sera (MOG-IgGSERUM), but there have been some seronegative MOGAD cases with MOG-IgG in CSF (MOG-IgGCSF), and its diagnostic implications remains unclear. In this cross-sectional study, we identified patients with paired serum and CSF sent from all over Japan for testing MOG-IgG. Two investigators blinded to MOG-IgG status classified them into suspected MOGAD (ADEM, CE, NMOSD, ON, MY and Others) or not based on the current recommendations. The MOG-IgGSERUM and MOG-IgGCSF titres were assessed with serial 2-fold dilutions to determine end point titres [≥1:128 in serum and ≥1:1 (no dilution) in CSF were considered positive]. We analysed the relationship between MOG-IgGSERUM, MOG-IgGCSF and the phenotypes with multivariable regression. A total of 671 patients were tested [405 with suspected MOGAD, 99 with multiple sclerosis, 48 with AQP4-IgG-positive NMOSD and 119 with other neurological diseases (OND)] before treatment. In suspected MOGAD, 133 patients (33%) tested MOG-IgG-positive in serum and/or CSF; 94 (23%) double-positive (ADEM 36, CE 15, MY 8, NMOSD 9, ON 15 and Others 11); 17 (4.2%) serum-restricted-positive (ADEM 2, CE 0, MY 3, NMOSD 3, ON 5 and Others 4); and 22 (5.4%) CSF-restricted-positive (ADEM 3, CE 4, MY 6, NMOSD 2, ON 0 and Others 7). None of AQP4-IgG-positive NMOSD, multiple sclerosis or OND cases tested positive for MOG-IgGSERUM, but two with multiple sclerosis cases were MOG-IgGCSF-positive; the specificities of MOG-IgGSERUM and MOG-IgGCSF in suspected MOGAD were 100% [95% confidence interval (CI) 99-100%] and 99% (95% CI 97-100%), respectively. Unlike AQP4-IgG-positive NMOSD, the correlation between MOG-IgGSERUM and MOG-IgGCSF titres in MOGAD was weak. Multivariable regression analyses revealed MOG-IgGSERUM was associated with ON and ADEM, whereas MOG-IgGCSF was associated with ADEM and CE. The number needed to test for MOG-IgGCSF to diagnose one additional MOGAD case was 13.3 (14.3 for ADEM, 2 for CE, 19.5 for NMOSD, infinite for ON, 18.5 for MY and 6.1 for Others). In terms of MOG-IgGSERUM/CSF status, most cases were double-positive while including either serum-restricted (13%) or CSF-restricted (17%) cases. These statuses were independently associated with clinical phenotypes, especially in those with ON in serum and CE in CSF, suggesting pathophysiologic implications and the utility of preferential diagnostic testing. Further studies are warranted to deduce the clinical and pathological significance of compartmentalized MOG-IgG.

Atypical and delayed spinal cord MRI features of COVID-19-associated myelopathies: a report of four cases and literature review.

We reported four patients with coronavirus disease 2019 (COVID-19)-associated myelopathies, highlighting the delayed and atypical spinal cord magnetic resonance imaging (MRI) features and the literature review. All four patients were males, aged 37 to 72 years old. The latencies from COVID-19 to the onset of myelitis were 5, 15, 30, and 80 days. The initial symptoms were numbness and weakness of lower limbs in three cases, and back pain with weakness of lower limbs in one case. The peak symptoms included paraplegia, sphincter dysfunction, sensory disturbance level, and spastic gait. The EDSS scores were 7.5, 9.0, 9.0, and 7.5, respectively. Magnetic resonance imaging (MRI) showed delayed atypical spinal cord lesions at onset, i.e., two cases without lesions, one with linear spinal meningeal enhancement, and one with punctate lesions on T2-weighted imaging (T2WI). During the follow-up period, punctate, linear, and cloudy lesions in the lateral and posterior funiculus were seen on T2WI in the peak stage. The prominent features of spinal cord lesions were linear spinal meningeal enhancement, the mismatch of deteriorated clinical symptoms, and inapparent MRI findings. All four patients were left with an obvious disability, with two patients completely bedridden and two who could stand with support. This report highlights the recognition of COVID-19-associated myelopathy even months after initial infection, especially in patients with delayed and atypical spinal cord findings on MRI.

Only anti-GM4 antibody positivity in a Chinese girl with overlapping MFS/GBS: a case report.

BACKGROUND: Guillain-Barré syndrome (GBS), as the most common cause of acute flaccid paralysis worldwide, is considered a part of a clinical spectrum in which discrete, complete, or incomplete forms of GBS and overlapping syndromes lie on the basis of their clinical features. The term overlapping Miller Fisher syndrome (MFS)/GBS is used when patients with MFS also suffer from progressive motor weakness of the limbs. Anti-ganglioside GQ1b has been specifically associated with MFS and ophthalmoplegia. CASE DESCRIPTION: Here, we report a Chinese girl who was diagnosed with overlapping MFS/GBS showing acute flaccid paralysis of all four limbs, sensory symptoms, cranial nerve dysfunction, autonomic involvement, ophthalmoplegia, and ataxia. She had high serum and cerebrospinal fluid titres of monospecific anti-GM4 IgG antibody instead of anti-GQ1b antibody in the acute phase. CONCLUSION: Anti-GM4 antibodies usually coexist with other antiganglioside antibodies, leading to missed diagnoses. The findings of the present study show that antibodies to ganglioside GM4 may in overlapping MFS/GBS as the lone immunological factors.

Neurological and neuromuscular manifestations in patients with West Nile neuroinvasive disease, Belgrade area, Serbia, season 2022.

INTRODUCTION: We aimed to describe neurological manifestations and functional outcome at discharge in patients with West Nile neuroinvasive disease. METHODS: This retrospective study enrolled inpatients treated in the University Clinic for Infectious and Tropical Diseases in Belgrade, Serbia, from 1 June until 31 October 2022. Functional outcome at discharge was assessed using modified Rankin scale. RESULTS: Among the 135 analyzed patients, encephalitis, meningitis and acute flaccid paralysis (AFP) were present in 114 (84.6%), 20 (14.8%), and 21 (15.6%), respectively. Quadriparesis/quadriplegia and monoparesis were the most frequent forms of AFP, present in 9 (6.7%) and 6 (4.4%) patients, respectively. Fourty-five (33.3%) patients had cerebellitis, 80 (59.3%) had rhombencephalitis, and 5 (3.7%) exhibited Parkinsonism. Ataxia and wide-based gait were present in 79 (58.5%) patients each. Fifty-one (37.8%) patients had tremor (41 (30.3%) had postural and/or kinetic tremor, 10 (7.4%) had resting tremor). Glasgow coma score (GCS) ≤ 8 and respiratory failure requiring mechanical ventilation developed in 39 (28.9%), and 33 (24.4%) patients, respectively. Quadriparesis was a risk factor for prolonged ventilator support (29.5 ± 16.8 vs. 12.4 ± 8.7 days, p = 0.001). At discharge, one patient with monoparesis recovered full muscle strength, whereas 8 patients with AFP were functionally dependent. Twenty-nine (21.5%) patients died. All of the succumbed had encephalitis, and 7 had quadriparesis. Ataxia, tremor and cognitive deficit persisted in 18 (16.9%), 15 (14.2%), and 22 (16.3%) patients at discharge, respectively. Age, malignancy, coronary disease, quadriparesis, mechanical ventilation, GCS ≤ 8 and healthcare-associated infections were risk factors for death (p = 0.001; p = 0.019; p = 0.004; p = 0.001; p < 0.001; p < 0.001, and p < 0.001, respectively).

Selective nerve transfers to restore shoulder abduction and flexion in acute flaccid myelitis: A case report.

Acute flaccid myelitis (AFM) is a polio-like condition predominantly affecting children that is characterized by acute-onset, asymmetric flaccid paralysis, often preceded by a prodromal fever or viral illness. With prompt diagnosis and early surgical referral, nerve transfers may be performed to improve function. Highly selective nerve transfers are ideal to preserve existing functions while targeting specific deficits. In this report, we present a case of a double fascicular nerve transfer of median and ulnar nerve fascicles to the axillary nerve, combined with selective transfer of the spinal accessory nerve to the supraspinatus branch of the suprascapular nerve, performed for a 5-year-old girl who developed AFM after an upper respiratory infection. Six months after the onset of the patient's symptoms, the patient had continued weakness of shoulder flexion and abduction, atrophy of the deltoid, and supraspinatus muscles, though needle electromyography revealed a functioning infraspinatus muscle. The patient had no post-operative complications and at 2 years of postoperative follow up achieved shoulder abduction and flexion Active Movement Scale scores of 7/7 compared to preoperative scores of 2/7, with no loss of function in the donor nerve domains. The patient showed active shoulder abduction against gravity to 90° from 30° preoperatively and shoulder flexion to 180° from 15° preoperatively. This case report shows that highly selective nerve transfers may preserve existing functions while targeting specific deficits. A double fascicular transfer from the median and ulnar nerves to axillary nerve may provide abundant axons for functional recovery.

[Pathogen-induced diseases of the spinal cord and adjacent structures]. / Erregerbedingte Erkrankungen des Rückenmarks und seiner angrenzenden Strukturen.

Pathogen-induced myelitis is an inflammatory disease of the spinal cord that can be caused by various pathogens including viruses, bacteria, fungi or parasites. The most frequent viral pathogens include herpes and enteroviruses, while bacterial myelitis can be caused by, e.g., Mycobacterium tuberculosis, Borrelia burgdorferi and Treponema pallidum. Fungi such as Candida and Aspergillus and parasites such as Toxoplasma gondii and schistosomes can also cause myelitis. The main symptom is subacute paraplegia with motor, sensory and autonomic deficits to varying degrees, often accompanied by fever and a general malaise. Following a thorough clinical examination and review of the medical history diagnostic imaging procedures, such as magnetic resonance imaging (MRI) along with cerebrospinal fluid analysis and blood tests that include antibody testing are warranted. The treatment is directed at the cause of the myelitis and mostly with anti-infective agents but for some viral pathogens no specific treatment is available and the only option is a symptomatic treatment. The prognosis is very variable and depends on the etiology and severity of the disease. A fast diagnosis and targeted treatment are crucial to achieve a good outcome.

Varicella-zoster virus myelitis as a cause of acute functional decline. / Varicella-zoster-virus-myelitt som årsak til akutt funksjonssvikt.

Background: Acute functional decline is a common reason for hospital admission for older people, often caused by an acute deterioration of an underlying chronic illness. However, occasionally a rare condition is detected. Case presentation: A woman in her eighties was admitted to hospital with acute functional decline. Hyponatraemia, urinary tract infection and pulmonary embolism were initially diagnosed. She developed increasing difficulties in using her legs, and assessment led to the diagnosis of varicella- zoster virus myelitis, which was treated with intravenous acyclovir. After a brief stay in the rehabilitation unit, the patient's condition acutely deteriorated, leading to readmission with neurovascular septic embolism and microvascular haemorrhage in the brain. Anticoagulation was terminated. After 52 days she was discharged to a nursing home for further rehabilitation. Interpretation: Our article presents a case of acute functional decline caused by a rare condition. Collaboration between the geriatric, neurological and infectious disease departments was needed. When treated rapidly with targeted therapy, the prognosis for myelitis is often good.

Trends of Enterovirus D68 Concentrations in Wastewater, California, USA, February 2021-April 2023.

In this retrospective study, we measured enterovirus D68 (EV-D68) genomic RNA in wastewater solids longitudinally at 2 California, USA, wastewater treatment plants twice per week for 26 months. EV-D68 RNA was undetectable except when concentrations increased from mid-July to mid-December 2022, which coincided with a peak in confirmed EV-D68 cases.

Animal Models of Enterovirus D68 Infection and Disease.

Human enterovirus D68 (EV-D68) is a globally reemerging respiratory pathogen that is associated with the development of acute flaccid myelitis (AFM) in children. Currently, there are no approved vaccines or treatments for EV-D68 infection, and there is a paucity of data related to the virus and host-specific factors that predict disease severity and progression to the neurologic syndrome. EV-D68 infection of various animal models has served as an important platform for characterization and comparison of disease pathogenesis between historic and contemporary isolates. Still, there are significant gaps in our knowledge of EV-D68 pathogenesis that constrain the development and evaluation of targeted vaccines and antiviral therapies. Continued refinement and characterization of animal models that faithfully reproduce key elements of EV-D68 infection and disease is essential for ensuring public health preparedness for future EV-D68 outbreaks.

Challenges in the Clinical Recognition of Acute Flaccid Myelitis and its Implications.

OBJECTIVES: To explore the challenges in diagnosing acute flaccid myelitis (AFM) and evaluate clinical features and treatment paradigms associated with under recognition. STUDY DESIGN: This was a retrospective multicenter study of pediatric patients (≤18 years) who were diagnosed with AFM from 2014 to 2018 using the Centers for Disease Control and Prevention's case definition. RESULTS: In 72% of the cases (126 of 175), AFM was not considered in the initial differential diagnosis (n = 108; 61.7%) and/or the patient was not referred for acute care (n = 90; 51.4%) at the initial clinical encounter, and this did not improve over time. Although many features of the presentation were similar in those initially diagnosed with AFM and those who were not; preceding illness, constipation, and reflexes differed significantly between the 2 groups. Patients with a non-AFM initial diagnosis more often required ventilatory support (26.2% vs 12.2%; OR, 0.4; 95% CI, 0.2-1.0; P = .05). These patients received immunomodulatory treatment later (3 days vs 2 days after neurologic symptom onset; 95% CI, -2 to 0; P = .05), particularly intravenous immunoglobulin (5 days vs 2 days; 95% CI, -4 to -2; P < .001). CONCLUSIONS: Delayed recognition of AFM is concerning because of the risk for respiratory decompensation and need for intensive care monitoring. A non-AFM initial diagnosis was associated with delayed treatment that could have a clinical impact, particularly as new treatment options emerge.

Transverse myelitis associated with systemic lupus erythematosus (SLE-TM): A review article.

Systemic lupus erythematosus-related transverse myelitis (SLE-TM) is a rare but serious complication of SLE, which may result in significant morbidity. Its incidence is estimated between 0.5% and 1% of all SLE patients but may be the presenting feature in 30%-60% of these patients. Unfortunately, due to lack of high-quality studies, data regarding this condition remains limited. Its pathogenesis remains largely unknown and clinical presentation is variable. There are still no set guidelines regarding diagnosis, management, or monitoring and the role of autoantibodies remains controversial. In this review, we aim to summarize the available data regarding the epidemiology, pathogenesis, clinical features, management, and prognosis of this rare disease.

Comparison of acute flaccid myelitis and transverse myelitis in children and evaluation of diagnostic criteria.

BACKGROUND AND PURPOSE: Acute flaccid myelitis (AFM) and transverse myelitis (TM) are serious conditions that may be difficult to differentiate, especially at onset of disease. In this study, we compared clinical features of pediatric AFM and TM and evaluated current diagnostic criteria, aiming to improve early and accurate diagnosis. METHODS: Two cohorts of children with enterovirus D68-associated AFM and clinically diagnosed TM were compared regarding presenting clinical features, additional investigations, and outcome. Current diagnostic criteria for AFM and TM were applied to evaluate their specificity. RESULTS: Children with AFM (n = 21) compared to those with TM (n = 36) were younger (median 3 vs. 10 years), more often had a prodromal illness (100% vs. 39%), predominant proximal weakness (69% vs. 17%), and hyporeflexia (100% vs. 44%), and less often had sensory deficits (0% vs. 81%), bowel and/or bladder dysfunction (12% vs. 69%), and hyperreflexia (0% vs. 44%). On magnetic resonance imaging, brainstem involvement was more common in AFM (74% vs. 21%), whereas supratentorial abnormalities were only seen in TM (0% vs. 40%). When omitting the criterion of a sensory level, 11 of 15 (73%) children with AFM fulfilled the diagnostic criteria for TM. Of children with TM, four of 33 (12%) fulfilled the diagnostic criteria for probable/definite AFM. CONCLUSIONS: Although there is considerable overlap between AFM and TM in children, we found important early differentiating clinical and diagnostic features. Meeting diagnostic criteria for AFM in children with TM and vice versa underlines the importance of thorough clinical examination and early and accurate diagnostic studies.