Detection of homogentisic acid by electrospray ionization mass spectrometry.

OBJECTIVE: Homogentisic acid (HGA) is excreted in excessive amounts in the urine of patients with alkaptonuria, which is a hereditary metabolic disorder of phenylalanine and tyrosine. Therefore, the detection of HGA in urine is useful for the diagnosis of alkaptonuria. To evaluate the detection of HGA, we confirmed the color shift of HGA solutions and analyzed them by electrospray ionization mass spectrometry (ESI-MS). METHODS: We observed the color change of the HGA solutions under different pH conditions (pH 6.0, 7.0, and 8.0) and examined the influences of adding potassium hydroxide (KOH) and ascorbic acid (AA) to the HGA solutions. Then, we analyzed the chemical reaction in HGA solutions using ESI-MS. RESULTS: The HGA solution at pH 8.0 became brown after incubation at room temperature for 24 h and became darker brown with the addition of KOH; however, HGA solutions at pH 6.0 and 7.0 showed no color changes. The brown color change of the HGA solution at pH 8.0 was also inhibited by AA. Moreover, all HGA sample solutions showed the deprotonated molecular ion peak at m/z 167.035 in the negative ion mode after incubation at room temperature for 24 h and with the addition of KOH and AA. CONCLUSION: We identified the molecular ion of HGA in all sample solutions by ESI-MS, regardless of different pH conditions, color changes, or the presence of AA. These results suggest that spectral analysis by ESI-MS is suitable for the detection of HGA and the diagnosis of alkaptonuria.

Clinical impact of antibodies to Sp100 on a bacterial infection in patients with primary biliary cholangitis.

BACKGROUND: A specific antinuclear antibody for primary biliary cholangitis (PBC) is anti-Sp100, which was recognized as a serological marker of concurrent urinary tract infection. We sought to determine the clinical characteristics of PBC patients who had anti-Sp100. PATIENTS AND METHODS: Fifty-one patients with PBC and 10 healthy controls (HCs) were enrolled. Anti-Sp100 were determined with an ELISA method. Lipopolysaccharide-binding protein (LBP) was measured as a serological hallmark for bacterial infection. The correlations of anti-Sp100 with demographic, laboratory, and pathological parameters were investigated. RESULTS: Six of the 51 (11.8%) PBC patients had anti-Sp100, whereas none of the HCs did. There was no significant difference in the frequency of antimitochondrial antibodies (AMAs) between PBC patients with and without anti-Sp100 (67% vs. 82%, p = 0.5839). Biochemical and immunological parameters were not associated with the emergence of anti-Sp100 in these patients. The clinical stage by Scheuer classification was not correlated with the existence of anti-Sp100. No significant difference in the serum LBP levels was found between PBC patients with and without anti-Sp-100, although serum LBP levels were significantly higher in PBC patients with anti-Sp100 than in HCs (8.30 ± 2.24 ng/ml, vs. 5.12 ± 2.48 ng/ml, p = 0.0022). The frequency of granuloma formation was higher in the liver specimens of PBC patients with anti-Sp100 than in those without anti-Sp100 (67% vs 29%, p = 0.0710). CONCLUSION: anti-Sp100 does not become a complementary serological marker for PBC in AMA-negative patients. A bacterial infection may trigger the production of anti-Sp100. Another factor is required to initiate the autoantibody production.

Acromioclavicular joint arthritis as the first manifestation of Austrian syndrome.

Austrian syndrome is a rare condition caused by invasive Streptococcus pneumoniae, comprising a triad of pneumococcal meningitis, endocarditis, and pneumonia. Herein, we report a 59-year-old male patient who presented with fever and tenderness of the right shoulder. Although the initial diagnosis was acromioclavicular joint septic arthritis, the present case showed a reduced level of consciousness, pulmonary infiltrates, cerebral infarcts, and destruction of the mitral valve. This case suggests that acromioclavicular joint arthritis could be an initial presentation of pneumococcal infection inclusive of Austrian syndrome, especially in patients with some risk factors of invasive pneumococcal infections, such as chronic alcoholism.

Method for ABO Blood Group Testing Using a General-Purpose Automated Biochemical Analyzer.

BACKGROUND: We investigated a high-throughput and high-precision forward ABO blood typing screening method that utilizes a general-purpose biochemical analyzer to perform direct red blood cell sampling. METHODS: The blood group antisera used were Ortho® BioClone® Anti-A Serum and Ortho® BioClone® Anti-B Se-rum. AFFIRMAGEN® Reagent Red Blood Cells (Ortho Clinical Diagnostics) were used for AB standard red blood cells. The general-purpose biochemical analyzer employed was the TBATM-120FR HbA1c measurement unit (Canon Medical Systems). RESULTS: ABO blood group of patient samples was determined based on values relative to amount of change in the AFFIRMAGEN® response. Repeatability was CV5% or lower, and testing of 1,112 patient samples showed 100% agreement between the results obtained using the proposed method and those obtained using the tube test method. CONCLUSIONS: The proposed method allows ABO blood typing to be performed simply, quickly, and with a high degree of precision.

Optimization of oral entacapone administration in patients undergoing levodopa-carbidopa intestinal gel treatment.

BACKGROUND: Levodopa-carbidopa intestinal gel (LCIG) treatment markedly reduces motor fluctuations in patients with Parkinson's disease; however, some patients undergoing LCIG treatment may demonstrate clinical deterioration in the afternoon. Entacapone, a catechol-O-methyltransferase inhibitor, may be a promising adjunctive option for LCIG-treated patients; however, the optimal timing of oral entacapone administration to ameliorate clinical symptoms in the afternoon remains unexplored. This study aimed to investigate the optimal timing of oral entacapone administration in patients with Parkinson's disease undergoing LCIG treatment. METHODS: Pharmacokinetic analysis and symptom assessment were performed on three days: a day without entacapone administration, day with oral entacapone administration at 13:00, and day with oral entacapone administration at 15:00. RESULTS: Eight LCIG-treated patients were enrolled, of whom seven completed this study. The relative plasma concentrations of levodopa with entacapone administration at 13:00 were gradually increased, especially at 18:00 and were significantly higher than those without entacapone administration (127.10 ± 25.06% vs. 97.51 ± 22.20%). The relative plasma concentrations of 3-O-methyldopa were gradually increased without entacapone administration, whereas those with entacapone administration at 13:00 were lower than those without entacapone administration, especially at 17:00 (97.47 ± 3.70% vs. 110.71 ± 9.84%). Administering oral entacapone at 15:00 increased and decreased the relative plasma concentrations of levodopa and 3-O-methyldopa, respectively, but without significant difference. The "Off" time was shorter with entacapone administration at 13:00 (0.43 ± 0.79 h) and at 15:00 (0.57 ± 0.79 h) than that without entacapone administration (1.14 ± 1.46 h). CONCLUSIONS: The concomitant use of oral entacapone in the early afternoon may be effective in improving afternoon symptoms in patients undergoing LCIG treatment.

Intrinsic and extrinsic mechanisms control the termination of cortical interneuron migration.

During development, neurons migrate from their site of origin to their final destinations. Upon reaching this destination, the termination of their migration is crucial for building functional architectures such as laminated structures and nuclei. How this termination is regulated, however, is not clear. Here, we investigated the contribution of cell-intrinsic mechanisms and extrinsic factors. Using GAD67-GFP knock-in mice and in utero electroporation cell labeling, we visualized GABAergic neurons and analyzed their motility in vitro. We find that the motility of GABAergic neurons in cortical slices gradually decreases as development proceeds and is almost abolished by the end of the first postnatal week. Consistent with this, a reduction of embryonic interneuron motility occurred in dissociated cultures. This is in part due to cell-intrinsic mechanisms, as a reduction in motility is observed during long-term culturing on glial feeder cells. Cell-intrinsic regulation is further supported by observations that interneurons labeled in early stages migrated more actively than those labeled in late stages in the same cortical explant. We found evidence suggesting that upregulation of the potassium-chloride cotransporter KCC2 underlies this intrinsic regulation. Reduced motility is also observed when embryonic interneurons are plated on postnatal cortical feeder cells, suggesting extrinsic factors derived from the postnatal cortex too contribute to termination. These factors should include secreted molecules, as cultured postnatal cortical cells could exercise this effect without directly contacting the interneuron. These findings suggest that intrinsic mechanisms and extrinsic factors coordinate to reduce the motility of migrating neurons, thereby leading to the termination of migration.

A spectrophotometric method for the determination of tryptophan following oxidation by the addition of sodium hypochlorite pentahydrate.

Tryptophan (Trp) is an essential amino acid that functions in various biological processes and human daily health. As the significant functions of Trp become more apparent, its measurement is becoming increasingly important in various situations. Herein, we improved the Trp color reaction based on the Hopkins-Cole reaction and established a simple colorimetric method for Trp determination using several different reagents, including sodium hypochlorite pentahydrate and monosodium glutamate. The detection method can be performed using safe materials, rather than conventional toxic substances, and induces a crimson color change with an absorption peak at 525 nm, enabling the quantification of Trp by simple spectrophotometry in just 10 min. This assay exhibited a linear detection range from 10 to 100 mg/L (R2 = 0.9996). The average recoveries in the spiked cerebrospinal fluid ranged from 90.5% to 104.3%, with a relative standard deviation of 0.27% (n = 3, 29.40 mg/L Trp) to 1.19% (n = 3, 72.90 mg/L Trp). This novel spectrophotometric method may enable many researchers and laboratory technicians to detect Trp in various sample solutions without expensive analytical instruments or complicated operations.

Clinical use of CSF neopterin levels in CNS demyelinating diseases.

BACKGROUND: There is some phenotypic overlap between MS, AQP4-IgG positive NMOSD, and MOG-IgG associated disease (MOGAD), and distinguishing a true relapse and a pseudorelapse can be difficult. CSF neopterin, a marker of inflammation-immune-mediated processes in the CNS, may be a useful marker in a wide range of CNS infectious and inflammatory diseases. We compared CSF neopterin levels and other CSF parameters in patients with MS, AQP4-IgG-positive NMOSD, and MOGAD and also investigated whether CSF neopterin levels can distinguish between active and inactive phases of the diseases. METHODS: We retrospectively reviewed the medical records of 22 patients with MS, 18 with AQP4-IgG-positive NMOSD, and five with MOGAD. CSF neopterin concentrations were measured by HPLC with fluorometric detection. RESULTS: CSF neopterin levels at diagnosis were significantly higher in patients with AQP4-IgG-positive NMOSD (52.77 ± 34.56 pmol/mL) than patients with MS (16.92 ± 5.03 pmol/mL, p < 0.001), and tended to be higher in patients with MOGAD (28.87 ± 9.66 pmol/mL) than patients with MS (p = 0.092). ROC analysis revealed that CSF neopterin most accurately discriminated between MS and AQP4-IgG-positive NMOSD (AUC, 0.912; sensitivity, 75.0%; specificity, 100.0%). At diagnosis/relapse and during remission, CSF neopterin most accurately discriminated between the disease phases in patients with MS (AUC, 0.779; sensitivity, 58.1%; specificity, 94.7%) and patients with AQP4-IgG-positive NMOSD (AUC, 0.934; sensitivity, 83.3%; specificity, 94.1%). CONCLUSION: Measurement of CSF neopterin may be useful for differential diagnosis and assessment of disease activity in CNS demyelinating diseases. Further studies with larger cohorts, including comparisons with other biomarkers, are needed to validate the utility of CSF neopterin.

Zonisamide Ameliorates Microglial Mitochondriopathy in Parkinson's Disease Models.

Mitochondrial dysfunction and exacerbated neuroinflammation are critical factors in the pathogenesis of both familial and non-familial forms of Parkinson's disease (PD). This study aims to understand the possible ameliorative effects of zonisamide on microglial mitochondrial dysfunction in PD. We prepared 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and lipopolysaccharide (LPS) co-treated mouse models of PD to investigate the effects of zonisamide on mitochondrial reactive oxygen species generation in microglial cells. Consequently, we utilised a mouse BV2 cell line that is commonly used for microglial studies to determine whether zonisamide could ameliorate LPS-treated mitochondrial dysfunction in microglia. Flow cytometry assay indicated that zonisamide abolished microglial reactive oxygen species (ROS) generation in PD models. Extracellular flux assays showed that LPS exposure to BV2 cells at 1 µg/mL drastically reduced the mitochondrial oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). Zonisamide overcame the inhibitory effects of LPS on mitochondrial OCR. Our present data provide novel evidence on the ameliorative effect of zonisamide against microglial mitochondrial dysfunction and support its clinical use as an antiparkinsonian drug.

Utility of Rectus Abdominis Ultrasound as a Respiratory Function Test for Amyotrophic Lateral Sclerosis.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) causes deterioration of respiratory function. Muscle weakness of the orbicularis oris interferes with the accurate assessment of respiratory function using spirometry. Reduced forced vital capacity (FVC) is an indicator that helps determine the appropriate timing to provide noninvasive ventilation (NIV) for the survival of ALS patients. We employed ultrasonography to evaluate changes in respiratory function by measuring the thickness of the rectus abdominis (RA) muscle as a possible alternative to spirometry. METHODS: Sixteen subjects with ALS were included in this study. The thickness of RA muscles was measured using ultrasonography, and respiratory fluctuations, such as vital capacity (VC), FVC, FEV1, percentage of predicted VC (%VC), percentage of predicted FVC (%FVC), percentage of predicted FEV1 (%FEV1), and FEV1/FVC, were evaluated using spirometry. RESULTS: Sixteen subjects underwent assessment by ultrasonography. A positive correlation was observed between the percent change in RA muscle thickness evaluated from maximal expiration to maximal inspiration and %VC (P = .001), %FVC (P = .001), FEV1 (P = .009), and %FEV1 (P = .02). CONCLUSIONS: RA ultrasonography was useful for predicting a reduction in VC in subjects with ALS and may help determine the best timing for introducing NIV.

Refractory Longitudinally Extensive Transverse Myelitis after Severe Acute Respiratory Syndrome Coronavirus 2 Vaccination in a Japanese Man.

Vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been developed and administered worldwide. There have been reports of neurological adverse events following immunization (AEFIs). We herein report a case of refractory longitudinally extensive transverse myelitis in a 75-year-old Japanese man following the first dose of the BNT162b2 vaccine. The patient developed total sensory loss below the umbilicus and complete paralysis in both legs. Although he was treated with steroid therapy and plasma exchange, his recovery was limited, and severe sequelae remained. Further studies, including large epidemiological studies, are required to understand the association between SARS-CoV-2 vaccines and neurological AEFI.

Impact of Intestinal Bacteria on Levodopa Pharmacokinetics in LCIG Therapy.

Background: Levodopa-carbidopa intestinal gel (LCIG) therapy is used in advanced Parkinson's disease (PD) and consists of continuous administration of levodopa directly into the jejunum through a percutaneous endoscopic gastro-jejunal (PEG-J) tube. Recently, the metabolism of levodopa by Enterococcus faecalis (E. faecalis) has been reported. Intestinal bacteria can also affect this therapy. Objectives: To investigate intestinal bacteria and examine its impact on levodopa blood concentration in patients with PD receiving LCIG therapy. Methods: We enrolled 6 patients receiving LCIG therapy in our department. After PEG-J tube replacement, intestinal bacteria were collected from the tip of the tube and were identified using culture and polymerase chain reaction (PCR) tests. Moreover, the presence of tyrosine decarboxylase, which metabolizes levodopa, was also confirmed by PCR test. The ability of these bacteria to metabolize levodopa was confirmed in vitro. Levodopa blood concentrations were also examined before PEG-J tube replacement. Results: Bacteria were detected in all 6 patients. E. faecalis was present in 4 patients. Moreover, tyrosine decarboxylase was detected in 2 patients. The identified bacteria displayed in vitro metabolization to dopamine in the 4 E. faecalis positive samples. The addition of carbidopa did not inhibit the metabolism of levodopa. However, there was no difference in the mean blood concentration of levodopa, regardless of the presence of E. faecalis. Conclusions: We found bacteria, including E. faecalis in the PEG-J tube. We observed levodopa metabolism in vitro, but there was no association with levodopa blood concentration. The effect of intestinal bacteria may be limited in patients receiving LCIG therapy.

Association between high-sensitivity C-reactive protein and left ventricular diastolic function assessed by echocardiography in patients with cardiovascular risk factors.

High-sensitivity C-reactive protein (hsCRP) has been demonstrated to play a causal role in atherosclerosis and to predict cardiovascular events in the general population. On the other hand, left ventricular (LV) hypertrophy and diastolic dysfunction assessed by echocardiography can also predict cardiovascular events in patients with cardiovascular risk factors. However, there are few data regarding the relationships among hsCRP, LV hypertrophy, and diastolic function. We examined the relationships among hsCRP, LV hypertrophy, and diastolic function in 185 patients (65±11 years), who had no overt heart disease, but had cardiovascular risk factors, including hypertension, diabetes, and dyslipidemia. Echocardiography was performed to measure the left ventricular mass index (LVMI) as a parameter of LV hypertrophy. LV diastolic function was assessed by the ratio (E/A) of early (E) and late (A) diastolic transmitral flows, early diastolic mitral annular velocity (E'), and the ratio (E/E') of E to E' using Doppler echocardiography. The hsCRP was correlated with LVMI (r=0.228, p=0.002), E' (r=-0.276, p<0.001), and E/E' (r=0.419, p<0.001). The E/E' as a parameter of LV diastolic function showed the closest correlation to hsCRP. These results indicate that elevated hsCRP reflects LV diastolic dysfunction rather than LV hypertrophy. We therefore suggest that hsCRP may be a marker of subclinical LV diastolic dysfunction in patients with cardiovascular risk factors.

Fasting state is one of the factors associated with plasma levodopa fluctuations during levodopa‒carbidopa intestinal gel treatment.

INTRODUCTION: Some patients with Parkinson's disease (PD) undergoing levodopa‒carbidopa intestinal gel (LCIG) treatment experience motor fluctuations in the afternoon. The migrating motor complex, a specific periodic migrating contraction pattern occurring in the stomach and small intestine during the fasting state, can affect drug absorption. We aimed to compare the pharmacokinetic parameters between two conditions (with and without lunch) and assessed the influence of the fasting state on the levodopa pharmacokinetics in LCIG treatment. METHODS: We evaluated the levodopa pharmacokinetics from 12:00 p.m. to 6:00 p.m. in 10 LCIG-treated PD patients in the presence and absence of lunch. RESULTS: The maintenance dose of LCIG correlated strongly with the mean plasma concentration of levodopa in the absence (r = 0.94, coefficient of determination (R2) = 0.89, p < 0.001) or presence of lunch (r = 0.96, R2 = 0.93, p < 0.001). Comparison of the pharmacokinetic parameters revealed that the coefficient of variation was significantly greater in the condition without lunch than in the condition with lunch (p = 0.004): 16.73% (4.88%) without lunch and 9.22% (3.80%) with lunch. There were no significant differences in the mean plasma concentration of levodopa (p = 0.49) and area under the plasma concentration‒time curve (p = 0.27) between the two conditions. CONCLUSIONS: Plasma concentrations of levodopa fluctuated more in patients undergoing LCIG treatment without than with lunch. Our results indicate that a small amount of food intake may be a better corrective approach for worsening of symptoms in the fasting state rather than additional levodopa.

Exendin-4 regulates pancreatic ABCA1 transcription via CaMKK/CaMKIV pathway.

ATP-binding cassette transporter A1 (ABCA1) in pancreatic beta cells influences insulin secretion and glucose homeostasis. This study investigates whether the long-acting agonist of the glucagon-like peptide 1, namely exendin-4, which mediates stimulatory effects on ABCA1 gene expression, could interfere with the Ca(2+)/calmodulin (CaM)-dependent protein kinase (CaMK) cascade. ABCA1 promoter activity was examined by reporter gene assay in rat insulin-secreting INS-1 cells incubated with exendin-4. CaMKIV activity was assessed by detection of activation-loop phosphorylation (Thr(196)) of CaMKIV. We investigated the influence of the constitutively active form (CaMKIVc) or CaMKIV knockdown on ABCA1 expression. Increased abundance of ABCA1 protein was noted in response to rising concentrations of exendin-4 with maximum induction at 10 nM. Exendin-4 also stimulated ABCA1 promoter activity, but failed to do so in the presence of STO-609, a CaMKK inhibitor. Up-regulation of CaMKIV phosphorylation (at Thr(196)) peaked after 10 min. of exposure to exendin-4. CaMKIVc enhanced or up-regulated ABCA1 promoter activity in INS-1 cells. Furthermore, exendin-4 induction of ABCA1 protein expression was significantly suppressed in cells treated with CaMKIV-siRNA. Activation of the CaMKK/CaMKIV cascade by exendin-4 stimulated ABCA1 gene transcription, indicating that exendin-4 plays an important role in insulin secretion and cholesterol ester content in pancreatic beta cells.

Reference urinary biopyrrin level and physiological variation in healthy young adults: relation of stress by learning.

BACKGROUND: Biopyrrins are end products of oxidation reactions of bilirubin with reactive oxygen, and urinary biopyrrin (UBP) levels might increase under oxidative stress. The authors examined the reference UBP level for healthy adults and its physiological variation in 40 healthy volunteers recruited from among students of our university (20 students each from third-year and fourth-year), and compared the results with data on 8-hydroxy-2-deoxyguanosine (8OHdG). METHODS: UBP and 8OHdG levels could be considered as oxidative stress markers. The UBP levels were measured with a competitive ELISA kit using biopyrrin antibody 24G7, according to the manufacturer's protocol. 8OHdG levels were measured with a Highly Sensitive 8-OHdG Check kit. UBP and 8OHdG measurements were performed in triplicate and means values calculated. For both parameters, creatinine (Cr) correction was performed using urinary creatinine levels measured by an enzymatic method. RESULTS: A comparison of the UBP levels between different grades revealed that the third-year students under high stress from clinical training and other course work tended to have a higher UBP level than fourth-year students. Therefore, we compared the current UBP levels in fourth-year students (samples collected in 2018) with their UBP level when they were in the third-year (samples collected in 2017) to examine the annual change. We found that the UBP level in 2017 samples was significantly higher than that in 2018 samples (P < 0.05). No difference in the 8OHdG level. Additionally, no effect of menstrual stress on the UBP level was observed. CONCLUSIONS: These results suggest that the UBP levels may be related to school-related stress and menstruation has no effects on urinalysis results.

Three cases of rheumatoid meningitis with elevated CSF neopterin levels.

Rheumatoid meningitis (RM) is a rare but treatable central nervous system (CNS) manifestation of rheumatoid arthritis (RA) with various clinical presentations and atypical cerebrospinal fluid (CSF) findings. There are no established biomarkers for RM, making diagnosis a challenge. Herein, we present three cases of RM: two patients with RA diagnosis and one without. CSF analysis showed pleocytosis in only one case. In contrast, CSF neopterin levels were elevated in all three cases and decreased after steroid therapy. This study suggests that CSF neopterin levels may be a useful biomarker for diagnosing and therapeutically monitoring CNS inflammation in patients with RM.

A double-blind, randomized controlled trial of duloxetine for pain in Parkinson's disease.

BACKGROUND: Duloxetine proved effective for treating pain in people with Parkinson's disease in a single-arm, open-label study. OBJECTIVE: To evaluate the efficacy of duloxetine in a double-blind, randomized, placebo-controlled trial. METHODS: We randomly assigned 46 patients with Parkinson's disease with pain to either the duloxetine 40 mg/day arm or the placebo arm. After 10 weeks, we tested the change from baseline in 24-hour average pain severity measured by a visual analogue scale. RESULTS: We could not confirm the effect of duloxetine on pain. Exploratory analyses indicated that treatment with duloxetine was associated with improved scores on the Unified Parkinson's Disease Rating Scale Part III and 3 domains of the Parkinson's Disease Questionnaire - 39. CONCLUSIONS: The study failed to provide evidence for the use of duloxetine for treating pain in people with Parkinson's disease.

Survey of patients with spinal muscular atrophy on the island of Shikoku, Japan.

BACKGROUND: Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder associated with spinal motor neuron loss and characterized by generalized muscle weakness. Only a few reports exist on SMA epidemiology in Japan. Additionally, nusinersen recently became available as a treatment for this condition. We estimated the prevalence of each type of SMA on Shikoku, Japan's fourth-largest major island. METHODS: We sent a questionnaire to all 131 hospitals in Shikoku that have pediatrics or neurology departments from March to September 2019, asking whether each hospital had SMA patients at that time. If so, we sent a second questionnaire to obtain more detailed information on the clinical data and treatment of each patient. RESULTS: A total of 117 hospitals (89.3%) responded to our first questionnaire, and 21 SMA patients were reported, 16 of whom had homozygous deletion of SMN1. Of the 21, nine had SMA type 1, five were type 2, five were type 3, one was type 4, and one was unidentified. The estimated prevalence for all instances of SMA and 5q-SMA was 0.56 and 0.43 per 100,000 people, respectively. Thirteen patients had received nusinersen therapy. Its outcomes varied from no obvious effects and being unable to sit to being able to sit independently. CONCLUSION: Our data showed the prevalence of SMA types 2 and 3 was relatively low on Shikoku compared with previous reports from other countries, suggesting delayed diagnosis may affect the results. Remaining motor function may be one predicting factor. Greater awareness of SMA among clinicians and patients seems necessary for more accurate epidemiological studies.