A case of anti-GA1 antibody-positive Fisher syndrome with elevated tau protein in cerebrospinal fluid

Pediatric Miller Fisher Syndrome; Characteristic Presentation and Comparison with Adult Miller Fisher Syndrome

Background: We aimed to investigate the characteristic presentation of Miller Fisher syndrome (MFS) in pediatrics and compare it with that in adults. Methods: We performed a retrospective review of medical records, laboratory findings, and disease course of pediatric MFS. The data were compared with those of adult MFS, and literature review was done. Unpaired and paired comparisons between groups were made using Wilcoxon rank-sum and signed-rank tests, respectively. Results: Median age for pediatric MFS was 9.8 ± 6.5 years. There were 5 (45.5%) male and 6 (54.5%) female patients. All patients had preceding infection. Two patients (22.2%) had tested positive for anti-GQ1b antibody. Ten patients (90.1%) were treated with intravenous immunoglobulin, and 2 (18.2%) also received intravenous methylprednisolone. Within one month, 8 (72.7%) patients showed recovery, and all 11 (100%) recovered fully within 3 months. Further, the pediatric group had higher frequency of unilateral involvement of ophthalmoplegia, ataxia, and autonomic symptoms but lower antiganglioside antibody positivity and manifestations of areflexia than the adult group. Conclusions: Neuro-ophthalmic manifestations and disease course of pediatric MFS were similar to those of adult MFS as stated in the literature. However, the presence of autonomic symptoms was higher and anti-GQ1b antibody positivity was lower in pediatric MFS than in adult MFS.

Neuropathogenesis of Zika Virus Infection : Potential Roles of Antibody-Mediated Pathology

Zika virus (ZIKV) is an enveloped, positive-sense, single-stranded RNA virus that belongs to the genus Flavivirus, family Flaviviridae, which includes many human and animal pathogens, such as dengue virus (DENV), West Nile virus, and Japanese encephalitis virus. In the original as well as subsequent experimental and clinical reports, ZIKV seems to have moderate neurotropism (in animal models) and neurovirulence (in human fetuses), but no neuroinvasiveness (in human adults). Intrauterine ZIKV infection (viral pathology) has been linked to an increased incidence of microcephaly, while increased Guillain-Barré syndrome (GBS) following ZIKV infection is likely immune-mediated (immunopathology). Clinically, in ZIKV infection, antibodies against other flaviviruses, such as DENV, have been detected; these antibodies can cross-react with ZIKV without ZIKV neutralization. In theory, such non-neutralizing antibodies are generated at the expense of decreased production of neutralizing antibodies ("antigenic sin"), leading to poor viral clearance, while the non-neutralizing antibodies can also enhance viral replication in Fc receptor (FcR)-bearing cells via antibody-dependent enhancement (ADE). Here, we propose three potential roles of the antibody-mediated pathogenesis of ZIKV infection: 1) cross-reactive antibodies that recognize ZIKV and neural antigens cause GBS; 2) ZIKV-antibody complex is transported transplacentally via neonatal FcR (FcRn), resulting in fetal infection; and 3) ZIKV-antibody complex is taken up at peripheral nerve endings and transported to neurons in the central nervous system (CNS), by which the virus can enter the CNS without crossing the blood-brain barrier.

Alternating ptosis associated with asialo-GM1 and GD1b antibodies

Miller Fisher syndrome (MFS), variant of acute inflammatory demyelinating polyradiculoneuropathy, is recognized as clinical triad (ophthalmoplegia-ataxia-areflexia). Ganglioside antibodies play an important role in the pathogenesis of acute polyradiculoneuropathy including MFS. To our knowledge, there has been no report of MFS presenting with atypical alternating ptosis or with concurrent elevation of serum GD1 and asialo-GM1 antibody titers, and negative titers of GQ1b antibody such as our patient. Our objective is to report MFS with unusual symptoms and to share our diagnostic approach. We report a rare case of MFS presenting with alternating eyelid ptosis, paresthesia, and ataxia after a respiratory infection. Initial neurological examination revealed left eyelid ptosis, hyporeflexia, positive Romberg sign, and ataxia. The ice pack test was negative. Three days later, contralateral ptosis was observed, associated with areflexia and worsened ataxia. However, there was significant improvement of the previous left eyelid ptosis. Serology revealed elevated asialo-GM1 and GD1b antibodies. Acetylcholine receptor antibodies were negative. Cerebral spinal fluid revealed elevated IgG index. Nerve conduction studies (NCS) performed four days after the onset of symptoms showed normal nerve conduction velocities and F-waves, and absent bilateral H-reflexes. Repetitive nerve stimulation (3 Hz) showed no decrement of compound muscle action potentials. Trial with a single dose of pyridostigmine showed no clinical improvement. The symptoms resolved without intervention. NCS 18 days after onset of symptoms showed mildly prolonged F-waves and absent H-reflexes. This case highlights an atypical presentation of MFS and raises the awareness of a rare autoantibody associated with it.

Global Epidemiology of Campylobacter Infection

Campylobacter jejuni infection is one of the most widespread infectious diseases of the last century. The incidence and prevalence of campylobacteriosis have increased in both developed and developing countries over the last 10 years. The dramatic increase in North America, Europe, and Australia is alarming, and data from parts of Africa, Asia, and the Middle East indicate that campylobacteriosis is endemic in these areas, especially in children. In addition to C. jejuni, there is increasing recognition of the clinical importance of emerging Campylobacter species, including Campylobacter concisus and Campylobacter ureolyticus. Poultry is a major reservoir and source of transmission of campylobacteriosis to humans. Other risk factors include consumption of animal products and water, contact with animals, and international travel. Strategic implementation of multifaceted biocontrol measures to reduce the transmission of this group of pathogens is paramount for public health. Overall, campylobacteriosis is still one of the most important infectious diseases that is likely to challenge global health in the years to come. This review provides a comprehensive overview of the global epidemiology, transmission, and clinical relevance of Campylobacter infection.

Serum and CSF biomarkers in acute pediatric neurological disorders

BACKGROUND

There have been numerous reports regarding serum or cerebrospinal fluid (CSF) biomarkers in various disorders; however, the validities of such biomarkers for more precise diagnoses and prognosis estimates remain to be determined, especially in pediatric patients with neurological disorders.

METHODS

Serum/CSF S100B, neuron-specific enolase, and total tau (tTau) were measured in various acute pediatric neurological disorders, and their usefulness for diagnostic and prognostic predictions was validated using receiver operating characteristic curves and area under the curve (AUC) analysis.

RESULTS

A total of 336 serum and 200 CSF specimens from 313 patients were examined, and we identified statistically significant differences that were relevant from diagnostic and prognostic viewpoints. CSF and serum tTau levels could be good predictors for diagnosis (CSF tTau; AUC=0.76) and prognosis (serum tTau; AUC=0.78).

CONCLUSIONS

Both CSF and serum tTau levels could be useful for precise diagnostic and prognostic estimations in acute pediatric neurological disorders. Further studies are needed to clarify the clinical significance of such biomarkers.