Chun-Che Chu’s research while affiliated with Chang Gung University and other places

Introduction For patients with acute intermittent porphyria (AIP), a true attack could be difficult to distinguish from chronic abdominal pain. This study focused on treatment responses from two patients with confirmed elevated biochemical data (delta-aminolevulinic acid (ALA), porphobilinogen (PBG)) and clinical evidence for acute attacks before starting givosiran. Methods Data from patients who participated in the phase III givosiran trial in Taiwan between May 2018 and May 2021 were reviewed. The pre-trial and post-trial biochemical data (urinary ALA/PBG), annualized attack rate (AAR), for two participants were obtained from our hospital record. Results Two patients had detailed records of biochemical evidence of acute attacks pre-trial (ALA:11.66–79.8 mg/24-h urine collection, PBG:75.45–160.11 mg/24-h). Patient Pb/Gn#1 with a disease duration of 1.6-years, had zero AAR during givosiran treatment. Patient Pb/Gn#2 had received prior hemin prophylaxis, had AIP for 6.7-years, had an AAR of 17.0 before givosiran, and an AAR of 12 at the post-trial compassionate-use period. The change in SF-12 PCS score from baseline was marginally clinical-meaningful (2.8 for Patient Pb/Gn#1 and 2.0 for Patient Pb/Gn#2). Conclusion Our data from 2 AIP patients with biochemical and clinical evidence of acute attacks suggested that patient with a shorter disease duration may respond better in terms of AAR. Further studies are necessary to understand the association between disease characteristics, treatment history, and optimal treatment response for patients with recurrent AIP in terms of both attack frequency and quality of life.

Aims/Introduction This study aims to investigate the association between cross‐sectional area (CSA) imaging findings of nerve ultrasound and conventional nerve conduction studies (NCS) for patients with distal symmetric sensorimotor polyneuropathy (DSPN) due to type 2 diabetes mellitus. Materials and Methods We enrolled 103 patients with type 2 diabetes mellitus and collected their demographic data, modified Michigan Neuropathy Screening Instrument (mMNSI) score, NCS, and ultrasonography images of peripheral nerves. The relationship of ultrasound variables for individual nerves and the ultrasound pattern sum score (UPSS) to conventional NCS findings was investigated. Results A higher grade of DSPN was associated with a notably higher CSA. Multivariate step‐wise regression analysis revealed that the number of abnormal nerves was a positive independent variable for UPSS (β coefficient = 0.4205; P < 0.0001). Of the five nerves studied, abnormalities of the tibial nerve (P ≤ 0.0100) and ulnar nerve (P = 0.052) were the most significant variables. Conclusions The tibial nerve exhibited the most substantial association with elevated UPSS. In addition, a strong correlation was observed between abnormal NCS findings and UPSS in patients with DSPN.

Aims This study aimed to identify metabolic markers for diabetic peripheral neuropathic pain (DPNP) in patients with type 2 diabetes mellitus (T2DM). Materials and Methods Blood metabolite levels in the amino acid, biogenic amine, sphingomyelin, phosphatidylcholine (PC), carnitines, and hexose classes were analyzed in nondiabetic control (n = 27), T2DM without DPNP (n = 58), and T2DM with DPNP (n = 29) using liquid chromatography tandem mass spectrometry. Variable importance projection (VIP) evaluation by partial least squares discriminant analysis was performed on clinical parameters and metabolites. Results Sixteen variables with VIP > 1.0 (P < 0.05) were identified across all patient groups, and 5 variables were identified to discriminate between the two T2DM groups. DPNP patients showed elevated fasting blood glucose, glutamate, PC aa C36:1, lysoPC a C18:1, and lysoPC a C18:2, while low‐density lipoprotein cholesterol, phenylalanine, and tryptophan were reduced. Glutamate, lysoPC a C18:1, and lysoPC a C18:2 discriminated T2DM with DPNP from those without DPNP with an AUC of 0.671. The AUC was improved to 0.765 when ratios of metabolite pairs were considered. Interpretation Blood metabolites include glutamate, and phospholipid‐related metabolites implicated in neuropathic pain may have the potential as biomarkers for DPNP. Further investigation is required to understand the mechanism of action of these altered metabolites in DPNP.

Background Distal symmetric sensorimotor polyneuropathy (DSPN) is a common neurologic complication of type 2 diabetes mellitus (T2DM), but the underlying mechanisms and changes in serum metabolites remain largely undefined. This study aimed to characterize the plasma metabolite profiles of participants with T2DM using targeted metabolomics analysis and identify potential biomarkers for DSPN. Methods A combined liquid chromatography MS/MS and direct flow injection were used to quantify plasma metabolite obtained from 63 participants with T2DM, 81 with DSPN, and 33 non‐diabetic control participants. A total of 130 metabolites, including amino acids, biogenic amines, sphingomyelins (SM), phosphatidylcholines, carnitines, and hexose were analyzed. Results A total of 16 plasma metabolites and 3 cholesterol‐related laboratory parameters were found to have variable importance in the projection score > 1.0 and false discovery rate <5.0% between control, T2DM, and DSPN. Among these variables, 5 serum metabolites including phenylalanine (AUC = 0.653), alanine (AUC = 0.630), lysine (AUC = 0.622) tryptophan (AUC = 0.620), and SM C16:0 (AUC = 0.630) are potential biomarkers (all p<0.05) in distinguishing T2DM with DSPN from those without (AUC = 0.720). Conclusions In this cross‐sectional study, derangement of several metabolites in the plasma was observed in T2DM with and without DSPN, and these metabolites may be potential biomarkers for predicting DSPN. Longitudinal studies are warranted. This article is protected by copyright. All rights reserved.

Background Approximately 10% to 20% of myasthenia gravis (MG) patients have experienced a myasthenic crisis (MC), which contributes to morbidity and mortality. MC triggered by infection is associated with poor outcomes. However, there is a lack of prognostic factors that clinicians can utilize to target interventions for preventing recurrent infection-triggered MC. This study aimed to characterize clinical manifestations, comorbidities, and biochemical profiles associated with recurrent infection-triggered MC in MG patients. Methods This retrospective study included 272 MG patients hospitalized with an infection requiring at least 3 days of antibiotics from January 2001 to December 2019. Patients were further stratified into non-recurrent or recurrent infection groups. Clinical features such as gender, age, concomitant diseases, acetylcholine receptor antibodies and biochemical data (including electrolytes and coagulants), muscle strength of pelvic and shoulder girdle, bulbar and respiratory function, management with an endotracheal tube, Foley catheter, or plasmapheresis, duration of hospitalization, and culture pathogens were recorded. Results The recurrent infection group was significantly older than the non-recurrent group (median age, 58.5 versus 52.0 years). Pneumonia was the most common infection and Klebsiella pneumoniae was the most common pathogen. The presence of concomitant diabetes mellitus, activated partial thromboplastin time prolongation, the duration of hospitalization, and hypomagnesaemia were independently associated with recurrent infection. The presence of deep vein thrombosis, thymic cancer, and electrolyte imbalances i.e., hypokalemia, and hypoalbuminemia were significantly associated with a risk for infection. The influence of endotracheal intubation, anemia, and plasmapheresis during hospitalization were inconsistent. Conclusions The independent risk factors for recurrent infections in MG patients identified in this study include the presence of concomitant diabetes mellitus, hypomagnesaemia, activated partial thromboplastin time prolongation, and longer duration of hospitalization, highlighting the need for targeted interventions to prevent recurrent infections in this population. Further research and prospective studies are warranted to validate these findings and refine interventions for optimizing patient care.

Currently, there is no objective biomarker to indicate disease progression and monitor therapeutic effects for amyotrophic lateral sclerosis (ALS). This study aimed to identify plasma biomarkers for ALS using a targeted metabolomics approach. Plasma levels of 185 metabolites in 36 ALS patients and 36 age- and sex-matched normal controls (NCs) were quantified using an assay combining liquid chromatography with tandem mass spectrometry and direct flow injection. Identified candidates were correlated with the scores of the revised ALS Functional Rating Scale (ALSFRS-r). Support vector machine (SVM) learning applied to selected metabolites was used to differentiate ALS and NC subjects. Forty-four metabolites differed significantly between ALS and NC subjects. Significant correlations with ALSFRS-r score were seen in 23 metabolites. Six of them showing potential to distinguish ALS from NC—asymmetric dimethylarginine (area under the curve (AUC): 0.829), creatinine (AUC: 0.803), methionine (AUC: 0.767), PC-acyl-alkyl C34:2 (AUC: 0.808), C34:2 (AUC: 0.763), and PC-acyl-acyl C42:2 (AUC: 0.751)—were selected for machine learning. The SVM algorithm using selected metabolites achieved good performance, with an AUC of 0.945. In conclusion, our findings indicate that a panel of metabolites were correlated with disease severity of ALS, which could be potential biomarkers for monitoring ALS progression and therapeutic effects.

Background: Neuromuscular ultrasound is a complementary technology that aids in the diagnosis of peripheral neuropathy. The interpretation of neuromuscular ultrasound results requires the use of accurate normative cross-sectional area (CSA) reference values. This study aims to provide CSA reference values specific to Taiwanese adults for Sonography of peripheral nerves in the upper and lower extremities. Methods: The study cohort included 66 healthy subjects (36 women; 30 men). A linear probe was used to measure the CSA of the median, ulnar, radial, tibial, sural, and peroneal nerves at multiple sites. These data were analyzed to determine standard ranges for the CSA at each site (reference range = mean ± 2 × SD) and identify correlations between the CSA and patient characteristics. Results: Normative CSA ranges were determined for all the assessed nerve sites, revealing that the nerve sizes in this Taiwanese population were smaller than Caucasian populations but comparable to those reported for other Asian cohorts. Men tended to have larger nerves than women, even after adjusting for height and weight. The size of ulnar nerve in the cubital tunnel and the peroneal nerve in the popliteal fossa correlated negatively with increasing age. The nerve size correlated positively with increasing weight and BMI at several sites, correlation of median nerve in the forearm with weight and BMI was significant after multiple testing. Significant correlation was also found between size of ulnar nerve in cubital tunnel and decreasing height. Conclusion: We provide reference ranges for neuromuscular ultrasound CSA values for the upper and lower extremities that are specific to the Taiwanese population. These reference values may be useful for evaluating peripheral neuropathy in Taiwanese subjects.

Autoimmune encephalitis with antibodies against the gamma-aminobutyric acid-B receptor is a relatively rare disease. We report a case with characteristic symptoms of limbic encephalitis associated with combined small cell lung carcinoma. The brain magnetic resonance imaging showed bilateral temporal lesions and the photoemission tomography revealed regional heterogenous metabolism across the brain. The double labeling of anti-gamma-aminobutyric acid-B receptor autoantibodies both in the tissues of neuroendocrine and small cell neoplasia was a unique feature of this patient.

Background The relationships among small fiber neuropathy, age, sex and pain intensity in the context of Fabry’s disease remain unclear. We aim to study the correlations of small fiber neuropathy, age, sex and pain intensity in Fabry patients. Methods We evaluated C-fiber function by recording the withdrawal latencies to painful heat stimulus (WLPHS) when each subject's right hand was immersed in a 50°C hot water bath and correlated this parameter with the patient’s perceived pain intensity and quality of life assessed by the short-form McGill Pain Questionnaire (SF-MPQ) in a large Taiwanese Fabry family and normal controls. Results Male Fabry patients showed a significantly increased WLPHS compared to that of normal controls. Furthermore, male Fabry patients showed a positive correlation of increased WLPHS with patient age. The SF-MPQ of male Fabry patients showed a bell distribution with age, and maximal pain scores were detected between the ages of the early 20s and late 40s. In contrast, the female Fabry patients had variable associations of WLPHS and SF-MPQ with age. Conclusions We proposed a probable mechanism by which globotriaosylceramide (Gb3) or globotriaosylsphingosine (lyso-Gb3) is gradually deposited into the small nerve bundles with increasing age, which induces continuous damage and produces injury discharges to sustain neuropathic pain in young male Fabry patients. However, once the small fibers are reduced to a certain degree, they no longer produce enough noxious discharges to sustain neuropathic pains in older male Fabry patients, which leads these patients to have lower SF-MPQ scores. In contrast, female Fabry patients had less and variable small fiber damage, pain intensity and clinical signs/symptoms.