CD11chigh B Cell Expansion Is Associated With Severity and Brain Atrophy in Neuromyelitis Optica

BACKGROUND AND OBJECTIVES

Neuromyelitis optica (NMO) is an autoimmune astrocytopathy mediated by anti-AQP4 antibody-producing B cells. Recently, a B-cell subset highly expressing CD11c and T-bet, originally identified as age-associated B cells, has been shown to be involved in the pathogenesis of various autoimmune diseases. The objective of this study was to determine the relationship between the frequency of CD11chigh B cells per CD19+ B cells in the peripheral blood of patients with NMO and the clinical profiles including the brain volume.

METHODS

In this observational study, 45 patients with anti-AQP4 antibody-positive NMO in remission and 30 healthy control subjects (HCs) were enrolled. Freshly isolated peripheral blood mononuclear cells were analyzed for immune cell phenotypes. The frequency of CD11chigh B cells per CD19+ B cells was assessed by flow cytometry and was evaluated in association with the clinical profiles of patients. Brain MRI data from 26 patients were included in the study for the analysis on the correlation between CD11chigh B-cell frequency and brain atrophy.

RESULTS

We found that the frequency of CD11chigh B cells in CD19+ B cells was significantly increased in patients with NMO compared with HCs. The expansion of CD11chigh B cells significantly correlated with EDSS, past relapse numbers, and disease duration. In addition, a higher frequency of CD11chigh B cells negatively correlated with total brain, white matter, and gray matter volumes and positively correlated with T2/FLAIR high lesion volumes. When the past clinical relapse episodes of patients with or without the expansion of CD11chigh B cells were compared, relapses in the brain occurred more frequently in patients with CD11chigh B-cell expansion. CD11chigh B cells had distinct features including expression of chemokine receptors associated with migration into peripheral inflammatory tissues and antigen presentation. CD11chigh B-cell frequency was positively correlated with T peripheral helper-1 (Tph-1) cell frequency.

DISCUSSION

Even during the relapse-free period, CD11chigh B cells could expand in the long disease context, possibly through the interaction with Tph-1 cells. The increased frequency of CD11chigh B cells associated with brain atrophy and disease severity, indicating that this cell population could be involved in chronic neuroinflammation in NMO.

Activation of a Cryptic Splice Site of GFAP in a Patient With Adult-Onset Alexander Disease

Background and Objective

Alexander disease (ALXDRD) is an autosomal dominant neurologic disorder caused by mutations in the glial fibrillary acidic protein (GFAP) gene and is pathologically defined by Rosenthal fiber accumulation. Most mutations are exonic missense mutations, and splice site mutations are rare. We report a very-late-onset autopsied case of adult-onset ALXDRD with a novel splice site mutation.

Methods

Genetic testing of GFAP was performed by Sanger sequencing. Using autopsied brain tissues, GFAP transcript analysis was performed.

Results

The patient presented mild upper motor neuron symptoms in contrast to the severe atrophy of spinal cord and medulla oblongata. The patient had c.619-1G>A mutation, which is located in the canonical splice acceptor site of intron 3. The brain RNA analysis identified the r.619_621del (p.Glu207del) mutation, which is explained by the activation of the cryptic splice acceptor site in the second and third nucleotides from the 5′ end of the exon 4.

Discussion

GFAP gene expression analysis is necessary to clarify the effects of intronic mutations on splicing, even if they are in canonical splice sites. This case showed a much milder phenotype than those in previous cases with missense mutations at Glu207, thereby expanding the clinical spectrum of ALXDRD with Glu207 mutation.

Pulse-gated noncontrast thoracic magnetic resonance angiography for acute aortic dissection with transient ischemic attack: A case report

Aortic dissection is a rare cause of an acute ischemic stroke or transient ischemic attack (TIA). Aortic dissection is particularly challenging in stroke patients who are eligible for thrombolysis secondary to the diagnostic difficulty within a narrow time window (4.5 h) and have a risk of developing life-threatening hemorrhagic complications following thrombolysis. Computed tomographic angiography (CTA) has been the mainstay of imaging when evaluating acute aortic syndrome. However, it cannot be routinely performed for pregnant patients and those with renal failure or iodine-contrast media allergy. We report a case of a 72-year-old woman who developed transient right-hand paralysis without any chest symptoms. Brain magnetic resonance imaging (MRI) showed no recent infarction; however, the brachiocephalic trunk was not well visualized on carotid magnetic resonance angiography (MRA). Subsequent thoracic pulse-gated noncontrast three-dimensional balanced steady-state free precession MRA (bSSFP-MRA) detected a Stanford type A acute aortic dissection (TAAAD). This was confirmed by CTA, leading to the diagnosis of TIA due to Stanford TAAAD. Pulse-gated noncontrast thoracic bSSFP-MRA was acquired a few minutes after a series of brain MRI scans. This imaging modality is expected to be used as a screening platform to rule out Stanford TAAAD during the hyperacute phase of stroke.

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CTA has been the mainstay of imaging when evaluating acute aortic syndrome.

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bSSFP-MRA can detect Stanford type A acute aortic dissection.

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Pulse-gated noncontrast thoracic bSSFP-MRA can screen for Stanford TAAAD.

AB1050 CLINICAL IMPLICATIONS OF ULTRASONOGRAPHY (US) IN DIAGNOSIS AND MONITORING DISEASE ACTIVITY OF RELAPSING POLYCHONDRITIS (RP) AND COMPARATIVE INVESTIGATION BY US BETWEEN AURICLE OF RP, REPEATED TRAUMA, CELLULITIS AND HEALTHY SUBJECT

Objectives:

To assess the clinical implications of ultrasonography (US) in monitoring disease activity and diagnosis of relapsing polychondritis (RP).

Methods:

Firstly, auricular (n=5) and nasal (n=1) chondritis of six patients with RP were assessed by US before and after treatments. The relationship between US findings and serum markers were evaluated. Moreover, the comparisons of US findings between the auricle of patients with RP (n=5), repeated trauma (n=5), cellulitis (n=2) and healthy subjects (n=5) were also assessed.

Results:

US finding before treatment showed low-echoic swollen auricular and nasal cartilage with increased power Doppler signals (PDS) in all cases of RP. US findings corresponded to biopsy findings. After treatment, the swollen ear and nose completely resolved. Then, US findings also showed dramatic reductions in swollen cartilage with the decrease in PDS. Although serum markers completely improved, US finding remained in 1 of 6 cases, and this case showed flare due to PSL tapering. Finally, RP could be differentiated from the damage of repeated trauma and cellulitis by the presence or absence of PDS and subperichondrial serous effusion.

Conclusion:

US of auricular and nasal cartilage in RP possibly facilitates evaluation of auricular lesions and monitoring of disease activity, especially when we consider the treatment response and the timing of drug tapering.

Disclosure of Interests:

None declared

Propionibacterium acnes-associated chronic hypertrophic pachymeningitis followed by refractory otitis media: a case report

BACKGROUND

Hypertrophic pachymeningitis (HP) is a rare disorder that involves localized or diffuse thickening of the dura mater. HP is associated with various inflammatory, infectious, and malignant diseases, such as rheumatic arthritis, sarcoidosis, anti-neutrophil cytoplasmic antibody-associated vasculitis, IgG4-related disorders, syphilis, tuberculosis, bacterial and fungal infections, cancer, and idiopathic diseases, when evaluation fails to reveal a cause. Among them, chronic infection with Propionibacterium acnes is a rare etiology of HP, and its pathology remains unclear.

CASE PRESENTATION

An 80-year-old man having refractory otitis media with effusion of the right ear presented with progressive right-sided headache and nausea. Post-contrast brain magnetic resonance imaging revealed right mastoiditis and remarkable thickening of the dura mater and enhancement of pia mater extending from the right middle cranial fossa to the temporal lobe. HP secondary to middle ear infection was suspected, and a biopsy of the right mastoid was performed. An anaerobic culture of the biopsied right mastoid showed the growth of P. acnes, and histopathological examination using P. acnes-specific monoclonal antibody (PAB antibody) revealed the infiltration of inflammatory cells with P. acnes. Moreover, using PAB antibody, P. acnes was detected in the biopsy specimen of the thickening dura mater. No granulomas were identified in either specimen. HP was resolved with long-term administration of antibiotics and steroids.

CONCLUSION

This is the first documentation of pathologically demonstrated chronic HP associated with P. acnes infection followed by refractory otitis media. This report showed that chronic latent P. acnes infection induces chronic inflammation.

Intrathecal IgG Synthesis and Persistent Inflammation Are Associated with White Matter Lesions in HIV-negative Patients with Cryptococcal Meningoencephalitis

Objective Cryptococcal meningoencephalitis (CM) causes significant morbidity and mortality in human immunodeficiency virus (HIV)-negative and HIV-positive populations. White matter lesions (WMLs) have been reported in both populations of CM patients; however, the mechanisms underlying WML formation remain unknown. We herein report the relationship between the intrathecal immune response and the development of WMLs in HIV-negative patients with CM. Methods Eleven consecutive HIV-negative patients with CM who presented at one of three emergency hospitals in Japan from April 2001 to March 2018 were enrolled. For all patients, we retrospectively assessed the relationships between clinical and laboratory information and the presence of WMLs. Results At presentation, 6 patients had WMLs on magnetic resonance imaging (MRI). The cerebrospinal fluid immunoglobulin G (CSF IgG) index was significantly higher in the patients with WMLs than in those without WMLs (mean, 1.34 vs. 0.70, p=0.017). The time from the symptom onset to initial neuroimaging was also significantly longer in the patients with WMLs than in those without WMLs (median, 31.5 vs. 7.0 days; p=0.008). The clinical outcome was comparable among the patients with and without WMLs. Conclusion In HIV-negative patients with CM, a persistent, aberrant immune response to Cryptococcus, such as intrathecal IgG synthesis, may induce WML formation.

Remarkable improvement in progressive multifocal leukoencephalopathy following acute pyelonephritis with bacteremia

Progressive multifocal leukoencephalopathy (PML) is caused by John Cunningham (JC) virus in immunocompromized patients such as those with human immunodeficiency virus (HIV) infection, hematological malignancy, autoimmune disorder, and immunodeficiency disorder as well as those undergoing chemotherapy or immunosuppressive therapy. No effective treatments have been established for PML, which commonly causes severe neurological sequelae. We describe the first case of PML in a patient without HIV infection who exhibited remarkable improvement following acute pyelonephritis with Escherichia coli bacteremia.

Late-onset paradoxical reactions 10 years after treatment for tuberculous meningitis in an HIV-negative patient: a case report

Background

Although paradoxical reactions (PRs) to anti-tuberculosis (anti-TB) therapy during treatment are well-established occurrences, PRs presenting as a new lesion after the completion of treatment are extremely rare, and little is known about the management of such cases, particularly of central nervous system (CNS) tuberculosis.

Case presentation

A 27-year-old female, with a past medical history of tuberculous meningitis 10 years ago and who completed the anti-TB treatment with asymptomatic remnant tuberculomas in the basal cistern, was admitted to our hospital because of a headache and the worsening of pre-existing visual disturbance. Contrast-enhanced T1-weighted brain magnetic resonance imaging (MRI) revealed new tuberculomas in the left sylvian fissure with a diffuse low signal around it. Because repeated polymerase chain reaction and Mycobacterium tuberculosis culture presented negative results and the patient had no laboratory data suggestive of a relapse of tuberculous meningitis, she was diagnosed with late-onset post-treatment PRs and treated with oral corticosteroids, tapered off over 1 year. Eventually, the symptoms were relieved, and the tuberculomas disappeared.

Conclusions

Clinicians should consider the possibility of PRs long after the completion of tuberculous meningitis treatment. Hence, a precise MRI-based examination is imperative for the follow-up of CNS tuberculosis, and the unnecessary administration of anti-TB drugs should be avoided. The use of corticosteroids as a treatment option for post-treatment PRs is seemingly safe when the isolated M. tuberculosis is sensitive to the first-line anti-TB therapy.

Dynamic spinal compression revealed by computed tomography myelography in overshunting-associated myelopathy: A case report

RATIONALE

OSAM is a rare ventriculoperitoneal (VP) shunt complication where cervical spinal cord compression by epidural venous plexus engorgement is caused by cerebrospinal fluid (CSF) overdrainage. Symmetrically indented deformity of the upper cervical spinal cord and surrounding epidural venous engorgement are characteristic radiological findings. Both of them are typically detected on magnetic resonance imaging (MRI) and enhanced computed tomography (CT).

PATIENT CONCERNS

The 77-year-old man who underwent the placement of a VP shunt without an antisiphon device to treat post-subarachnoid hemorrhage (SAH) hydrocephalus presented with progressive quadriplegia 10 years postoperatively.

DIAGNOSIS

MRI revealed a symmetrically indented spinal cord from the craniocervical junction (CCJ) to the C2 level and enhanced CT showed the epidural venous engorgement, which were characteristic radiological findings of overshunting-associated myelopathy (OSAM). However, MRI atypically failed to detect the engorged epidural vein and showed no compressive lesion around the spinal cord.

INTERVENTION

In order to reveal how the cervical spinal cord was deformed and compressed by engorged epidural vein, CT myelography was performed.

OUTCOMES

CT myelography proved that the epidural vein dynamically engorged and compressed the cervical spinal cord immediately after rotation and extension of the neck.

LESSONS

CT myelography combined with neck rotation and extension revealed the dynamic change of the epidural venous engorgement, and is useful for evaluation and diagnosis of OSAM especially when epidural venous engorgement was not detectable on MRI.

Pitfalls in the diagnosis of pupil-sparing oculomotor nerve palsy without limb ataxia: A case report of a variant of Claude's syndrome and neuroanatomical analysis using diffusion-tensor imaging

Midbrain infarction causing oculomotor nerve palsy with contralateral ataxia is named Claude's syndrome. Herein we report the case of a variant of Claude's syndrome, which shows pupil-sparing oculomotor nerve palsy without the accompanying neurological deficits other than subtle truncal ataxia. MRI and Diffusion Tensor Imaging revealed that midbrain infarction was located rostrally above the decussation of the superior cerebellar peduncle (SCP) and might have partially destructed the tectospinal tract, which resulted in the absence of limb ataxia and presence of subtle truncal ataxia. In this variant of Claude's syndrome, we should carefully assess truncal ataxia to avoid misdiagnosing it as isolated pupil-sparing oculomotor nerve palsy because the patient showed apparently normal gait and truncal ataxia was only revealed by unstable tandem gait.

[A case of renal oncocytoma with cystic formation]

A 60-year-old man was admitted to our hospital because of a right renal mass incidentally detected by ultrasonography during a general health check. Computerized tomography (CT) and magnetic resonance imaging (MRI) revealed a solid mass measuring 6 cm diameter containing a cystic portion in the right kidney. Cystic renal cell carcinoma was suspected, and right nephrectomy was performed. The gross appearance showed a well circumscribed mahogany brown tumor in the lower portion. On cross section of the tumor, a solid mass was seen in the cystic portion. Microscopically, oncocytic cells with eosinophilic granular cytoplasm were scattered on the cystic wall, and tumor cells formed microcystic structures in the solid part. Therefore, the tumor was diagnosed as renal oncocytoma with cystic formation. Only twelve cases have previously been reported in the literature.

A rice (Oryza sativa L.) mutant having a low content of glutelin and a high content of prolamine

Among the mutant lines of rice that have been selected for morphological characters, one line, NM67, was found to have a low content of glutelin and a higher content of prolamine in its seed protein than other Japanese cultivars. This mutant is a semi-dwarf and partially sterile line, and its leaves turn yellow before heading. Genetic analysis after backcross to the original cultivar, 'Nihonmasari', revealed the following: (1) the character of low glutelin content was always accompanied by the character of high prolamine content; (2) the low glutelin (and high prolamine) character seemed to be manifested by a single dominant gene; and (3) semi-dwarfness, low fertility and early yellowing leaf of the mutant, which might also be pleiotropy, were controlled by a single recessive gene independent of the gene for protein content. The protein character of NM67 was genetically separated from semi-dwarfness and low fertility, and a new line having low glutelin content and high prolamine content with normal morphological characters comparable to those of the original cultivar was obtained from the progenies of the cross. The possible use of this line as a low protein rice cultivar is discussed.

Flow system for automated analysis of maize pollen

Pollen grains are haploid gametes of uniform shape and size, and can be obtained in large quantity. If appropriate traits are used, they can be an excellent material for investigation of rare but important biological events like intracistronic recombinations or mutations induced by very low level of mutagens. This advantage will be further improved, if the laborious counting and examination can be made automatically. For automation of pollen analysis, techniques of flow analysis and image analysis would be applicable. Flow analysis with a optical detector was tested using maize pollen. Pollen grains were transported by gentle suction through a glass capillary which was placed under a microscope. Interruptions of the light path by pollen grains were detected by a silicon photocell after optical magnification and converted into electric pulses. The frequency distribution of pulse height was examined by a multichannel pulse height analyzer. 10(6) pollen grains would be counted and classified within about 30 min for a pollen suspension dilute enough for separation of each pulse. The flow system tested seems promising for detection of Wx mutant pollen in a wx pollen population after iodine staining if illumination of sample particles is improved.

Genetic and biochemical characterization of waxy mutants in cereals

During fine structure analyses of artificially induced waxy mutants in maize by use of Nelson's pollen analysis methods, it was noticed that some mutants showed a phenotype intermediate between waxy and normal nonwaxy. Such intermediate or leaky waxy mutants were frequent among mutants induced by a chemical mutagen, EMS. They seemed to be located evenly within the waxy locus. This would suggest that they might have been missense mutations, which would produce full-sized but partially inactivated enzymes, rather than deletions or frameshift mutations. To confirm the intermediate phenotype, a rapid measuring system was developed to measure waxiness of endosperm quantitatively. It was based on the blue value method and is applicable to a single grain of rice. Among the 27 waxy mutant lines of maize, including 11 EMS-induced, two of the EMS-induced mutants were clearly intermediate. Eighteen EMS induced wx mutants of rice were also examined, and nine were intermediate.

Evaluation of the DuPont aca amylase method

The dilution/activity curve for the DuPont aca kinetic amylase (EC 3.2.1.1) method is linear to approximately six times the upper limit of the expected range. Total reaction time on the aca is 4.3 min; however, there is a nonlinear rate of change in absorbance for at least the first 8 min, which is consistent with a lag phase. The within-run and day-to-day coefficients of variation were 2.4% at 100 U/L and 3.6% at 114 U/L, respectively. There was no interference by marked hemolysis (hemoglobin 4 g/L) or by glucose concentrations of 10--50 g/L. Comparisons by the split-sample method between the Amylochrome procedure and the aca procedure gave correlation coefficients of 0.992 for serum and 0.989 for urine. A second comparison, between the AutoAnalyzer I method and the aca, gave correlation coefficients of 0.998 for serum and 0.909 for urine. The expected range for serum was 18--106 U/L and for urine 2--33 U/2 h.

Subcellular distribution and activation by non-ionic detergents of guanylate cyclase in cerebral cortex of rat

Non-ionic detergents stimulated particulate guanylate cyclase activity in cerebral cortex of rat 8- to 12-fold while stimulation of soluble enzyme was 1.3- to 2.5-fold. Among various detergents, Lubrol PX was the most effective one. The subcellular distribution of guanylate cyclase activity was examined with or without 0.5% Lubrol PX. Without Lubrol PX two-thirds of the enzyme activity was detected in the soluble fraction. In the presence of Lubrol PX, however, two-thirds of guanylate cyclase activity was recovered in the crude mitochondrial fraction. Further fractionation revealed that most of the particulate guanylate cyclase activity was associated with synaptosomes. The sedimentation characteristic of the particulate guanylate cyclase activity was very close to those of choline acetyltransferase and acetylcholine esterase activities, two synaptosomal enzymes. When the crude mitochondrial fraction was subfractionated after osmotic shock, most of guanylate cyclase activity as assayed in the absence of Lubrol PX was released into the soluble fraction while the rest of the enzyme activity was tightly bound to synaptic membrane fractions. The total guanylate cyclase activity recovered in the synaptosomal soluble fraction was 6 to 7 times higher than that of the starting material. The specific enzyme activity reached more than 1000 pmol per min per mg protein, which was 35-fold higher than that of the starting material. The membrane bound guanylate cyclase activity was markedly stimulated by Lubrol PX. Guanylate cyclase activity in the synaptosomal soluble fraction, in contrast, was suppressed by the addition of Lubrol PX. The observation that most of guanylate cyclase activity was detected in synaptosomes, some of which was tightly bound to the synaptic membrane fraction upon hypoosmotic treatment, is consistent with the concept that cyclic GMP is involved in neural transmission.