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Current Gastroenterology Reports Sep 2023Acute Colonic Pseudo-obstruction (ACPO) is a cause of large intestinal dilation and obstruction without any physical transition point. It remains difficult to diagnose... (Review)
Review
PURPOSE OF REVIEW
Acute Colonic Pseudo-obstruction (ACPO) is a cause of large intestinal dilation and obstruction without any physical transition point. It remains difficult to diagnose and treat. We review the recent updates on diagnosis and management of ACPO.
RECENT FINDINGS
Recent guidelines have posited that conservative management can be tried in most cases of ACPO, but that early decompression and surgery should be considered. Use of neostigmine is still a viable option but there is also promising data on pyridostigmine as well as prucalopride. Resolution of ACPO should be followed by daily use of polyethylene glycol (PEG) to help prevent recurrence. ACPO warrants early and accurate diagnosis with exclusion of alternate causes of large bowel dilation. Conservative management can be attempted for 48-72 h in those with cecal diameters < 12 cm and without signs of peritonitis and perforation. Early escalation of management should be attempted with neostigmine followed by endoscopy and/or surgery as needed, given that longer periods of dilation are associated with worse outcomes. There is promising new evidence for use of pyridostigmine and prucalopride, but further trials are needed prior to incorporating them into regular use. Finally, studies are lacking regarding prevention of ACPO after initial resolution.
Topics: Humans; Acute Disease; Colonic Pseudo-Obstruction; Endoscopy, Gastrointestinal; Neostigmine; Polyethylene Glycols; Pyridostigmine Bromide; Cholinesterase Inhibitors; Parasympathomimetics; Treatment Outcome
PubMed: 37486594
DOI: 10.1007/s11894-023-00881-w -
ANZ Journal of Surgery Sep 2023Chronic intestinal pseudo-obstruction (CIPO) may be a primary or secondary phenomenon and is often multifactorial. Treatment is largely directed at improving colonic... (Review)
Review
BACKGROUND
Chronic intestinal pseudo-obstruction (CIPO) may be a primary or secondary phenomenon and is often multifactorial. Treatment is largely directed at improving colonic motility. The use of cholinesterase inhibitors such as pyridostigmine has been hypothesized to increase acetylcholine in the bowel, improving symptoms and transit times.
METHODS
A systematic review of the use of pyridostigmine in CIPO was conducted using scientific and commercial search engines identifying scientific studies enrolling adult human subjects, published from 2000 to 2022 in the English language.
RESULTS
Four studies were identified including two randomized controlled trials (RCT) and two observational studies. The studies had heterogenous inclusion criteria, dosing regimens and reported outcomes. Two studies were identified as being at high risk of bias. All studies reported improved patient outcomes with use of pyridostigmine, and low rates (4.3%) of mild cholinergic side effects. No major side effects were reported.
CONCLUSION
The use of pyridostigmine in management of CIPO is biologically plausible due to its ability to increase colonic motility, and early studies on its role are uniformly suggestive of benefit with low side-effect profile. Four clinical studies have been conducted to date, with small sample sizes, heterogeneity and high risk of bias. Further high-quality studies are required to enable assessment of pyridostigmine's utility as an effective management strategy in CIPO.
Topics: Adult; Humans; Pyridostigmine Bromide; Gastrointestinal Motility; Intestinal Pseudo-Obstruction; Cholinesterase Inhibitors; Chronic Disease
PubMed: 37132128
DOI: 10.1111/ans.18478 -
Brain, Behavior, and Immunity Oct 2023Gulf War Illness (GWI) collectively describes the multitude of central and peripheral disturbances affecting soldiers who served in the 1990-1991 Gulf War. While the...
Gulf War Illness (GWI) collectively describes the multitude of central and peripheral disturbances affecting soldiers who served in the 1990-1991 Gulf War. While the mechanisms responsible for GWI remain elusive, the prophylactic use of the reversible acetylcholinesterase inhibitor, pyridostigmine bromide (PB), and war-related stress have been identified as chief factors in GWI pathology. Post-deployment stress is a common challenge faced by veterans, and aberrant cholinergic and/or immune responses to these psychological stressors may play an important role in GWI pathology, especially the cognitive impairments experienced by many GWI patients. Therefore, the current study investigated if an immobilization stress challenge would produce abnormal responses in PB-treated rats three months later. Results indicate that hippocampal cholinergic responses to an immobilization stress challenge are impaired three months after PB administration. We also assessed if an immune or stress challenge reveals deficits in PB-treated animals during hippocampal-dependent learning and memory tasks at this delayed timepoint. Novel object recognition (NOR) testing paired with either acute saline or lipopolysaccharide (LPS, 30 µg/kg, i.p.), as well as Morris water maze (MWM) testing was conducted approximately three months after PB administration and/or repeated restraint stress. Rats with a history of PB treatment exhibited 24-hour hippocampal-dependent memory deficits when challenged with LPS, but not saline, in the NOR task. Similarly, in the same cohort, PB-treated rats showed 24-hour memory deficits in the MWM task. Ultimately, these studies highlight the long-term effects of PB treatment on hippocampal function and provide insight into the progressive cognitive deficits observed in veterans with GWI.
Topics: Rats; Animals; Persian Gulf Syndrome; Gulf War; Lipopolysaccharides; Acetylcholinesterase; Cholinesterase Inhibitors; Pyridostigmine Bromide; Cognitive Dysfunction; Memory Disorders; Disease Models, Animal
PubMed: 37437820
DOI: 10.1016/j.bbi.2023.07.003 -
European Journal of Neurology May 2024Generalized myasthenia gravis (MG) with antibodies against the acetylcholine receptor is a chronic disease causing muscle weakness. Access to novel treatments warrants...
BACKGROUND
Generalized myasthenia gravis (MG) with antibodies against the acetylcholine receptor is a chronic disease causing muscle weakness. Access to novel treatments warrants authoritative treatment recommendations. The Nordic countries have similar, comprehensive health systems, mandatory health registers, and extensive MG research.
METHODS
MG experts and patient representatives from the five Nordic countries formed a working group to prepare treatment guidance for MG based on a systematic literature search and consensus meetings.
RESULTS
Pyridostigmine represents the first-line symptomatic treatment, while ambenonium and beta adrenergic agonists are second-line options. Early thymectomy should be undertaken if a thymoma, and in non-thymoma patients up to the age of 50-65 years if not obtaining remission on symptomatic treatment. Most patients need immunosuppressive drug treatment. Combining corticosteroids at the lowest possible dose with azathioprine is recommended, rituximab being an alternative first-line option. Mycophenolate, methotrexate, and tacrolimus represent second-line immunosuppression. Plasma exchange and intravenous immunoglobulin are used for myasthenic crises and acute exacerbations. Novel complement inhibitors and FcRn blockers are effective and fast-acting treatments with promising safety profiles. Their use depends on local availability, refunding policies, and cost-benefit analyses. Adapted physical training is recommended. Planning of pregnancies with optimal treatment, information, and awareness of neonatal MG is necessary. Social support and adaptation of work and daily life activities are recommended.
CONCLUSIONS
Successful treatment of MG rests on timely combination of different interventions. Due to spontaneous disease fluctuations, comorbidities, and changes in life conditions, regular long-term specialized follow-up is needed. Most patients do reasonably well but there is room for further improvement. Novel treatments are promising, though subject to restricted access due to costs.
Topics: Pregnancy; Female; Infant, Newborn; Humans; Middle Aged; Aged; Myasthenia Gravis; Receptors, Cholinergic; Neuromuscular Diseases; Pyridostigmine Bromide; Immunosuppressive Agents; Thymus Neoplasms; Autoantibodies; Thymectomy
PubMed: 38321574
DOI: 10.1111/ene.16229 -
Journal of Medical Case Reports Sep 2023Myasthenia gravis is an autoimmune condition affecting the neuromuscular junction and causing muscle weakness along with fatigue (myasthenia). When the clinical...
BACKGROUND
Myasthenia gravis is an autoimmune condition affecting the neuromuscular junction and causing muscle weakness along with fatigue (myasthenia). When the clinical manifestations of myasthenia gravis are isolated to the eye muscles, only causing weak eye movements, it is referred to as ocular myasthenia gravis, which can mimic a 1 and ½ syndrome.
CASE PRESENTATION
An African-American female in her fifties with past medical history of hypertension presented to our outpatient clinic with complaints of blurred vision for two weeks. Her symptoms were associated with facial discomfort and a generalized headache. On physical examination upon her initial presentation, there was demonstratable swelling of the left upper eyelid with drooping. Her extraocular movements revealed defects with the abduction and adduction of the right eye, and the left eye would not adduct, although the outward movement was normal. The left eye failed to lift/elevate completely when looking upwards, a pseudo 1 and ½ syndrome. A positive Cogan lid twitch was also noticed. Imaging of the brain and orbit ruled out central causes. Diagnosis of ocular myasthenia gravis was made in accordance with positive anti-acetylcholine receptor antibodies. With 120 mg pyridostigmine oral dose, the patient experienced improvement subjectively and objectively, and the patient was discharged on oral pyridostigmine and prednisone. Six months later, with prednisone having been tapered off, the patient developed a myasthenic crisis and was treated with plasmapheresis and intravenous immunoglobulins. After recovering from the myasthenic crisis, efgartigimod infusions were instituted, which helped our patient restore normal life.
CONCLUSION
Our patient who presented with "blurred vision" was discovered to have binocular diplopia due to significant dysconjugate eye movements. After diligently ruling out central etiologies, we concluded that her presentation was due to a peripheral etiology. Her serologies and her presentation helped confirm a diagnosis of ocular myasthenia gravis. Also, as in most cases, our patient also progressed to develop generalized myasthenia gravis while on pyridostigmine. Efgartigimod infusions instituted after our patient recovered from a myasthenic crisis have helped her restore a normal life.
Topics: Female; Humans; Diplopia; Pyridostigmine Bromide; Prednisone; Vision Disorders; Myasthenia Gravis; Muscle Weakness
PubMed: 37679826
DOI: 10.1186/s13256-023-04089-4 -
Journal of Biochemical and Molecular... Mar 2024Obesity is a major cause of nonalcohol fatty liver disease (NAFLD), which is characterized by hepatic fibrosis, lipotoxicity, inflammation, and apoptosis. Previous... (Review)
Review
Obesity is a major cause of nonalcohol fatty liver disease (NAFLD), which is characterized by hepatic fibrosis, lipotoxicity, inflammation, and apoptosis. Previous studies have shown that an imbalance in the autonomic nervous system is closely related to the pathogenesis of NAFLD. In this study, we investigated the effects of pyridostigmine (PYR), a cholinesterase (AChE) inhibitor, on HFD-induced liver injury and explored the potential mechanisms involving mitochondrial damage and oxidative stress. A murine model of HFD-induced obesity was established using the C57BL/6 mice, and PYR (3 mg/kg/d) or placebo was administered for 20 weeks. PYR reduced the body weight and liver weight of the HFD-fed mice. Additionally, the serum levels of IL-6, TNF-α, cholesterol, and triglyceride were significantly lower in the PYR-treated versus the untreated mice, corresponding to a decrease in hepatic fibrosis, lipid accumulation, and apoptosis in the former. Furthermore, the mitochondrial morphology improved significantly in the PYR-treated group. Consistently, PYR upregulated ATP production and the mRNA level of the mitochondrial dynamic factors OPA1, Drp1 and Fis1, and the mitochondrial unfolded protein response (UPRmt) factors LONP1 and HSP60. Moreover, PYR treatment activated the Keap1/Nrf2 pathway and upregulated HO-1 and NQO-1, which mitigated oxidative injury as indicated by decreased 8-OHDG, MDA and H O levels, and increased SOD activity. Finally, PYR elevated acetylcholine (ACh) levels by inhibiting AChE, and upregulated the α7nAChR and M3AChR proteins in the HFD-fed mice. PYR alleviated obesity-induced hepatic injury in mice by mitigating mitochondrial damage and oxidative stress via α7nAChR and M3AChR.
Topics: Mice; Animals; Non-alcoholic Fatty Liver Disease; Pyridostigmine Bromide; alpha7 Nicotinic Acetylcholine Receptor; Kelch-Like ECH-Associated Protein 1; Chemical and Drug Induced Liver Injury, Chronic; Mice, Inbred C57BL; NF-E2-Related Factor 2; Liver; Oxidative Stress; Liver Cirrhosis; Obesity; Diet; Diet, High-Fat
PubMed: 38454809
DOI: 10.1002/jbt.23671 -
Pediatric Neurology Apr 2024Currently, there is no universally accepted standard treatment for ocular myasthenia gravis (OMG) in children. We aimed to investigate the possible proper regimens and...
BACKGROUND
Currently, there is no universally accepted standard treatment for ocular myasthenia gravis (OMG) in children. We aimed to investigate the possible proper regimens and timing of treatment for pediatric OMG cases based on the clinical manifestations: OMG with ptosis only and OMG with other features.
METHODS
One hundred and forty two OMG cases attended at the Department of Pediatrics, Xiangya Hospital, Central South University, from 2010 to 2019 were included, and information from medical records was reviewed and recorded. Comparisons of clinical characteristics between patients with OMG with ptosis only and patients with OMG with other features as well as between patients treated with glucocorticoid (GC) within or after six months from disease onset were performed.
RESULTS
OMG with other features constituted about 54.9% of the cases, and 66.2% of the patients achieved optimal outcome. Patients with OMG with ptosis only responded to pyridostigmine alone more than patients with OMG with other features who required several therapies (P < 0.001). Patients with OMG with ptosis only had a larger proportion of optimal outcome than the patients with OMG with other features (P = 0.002), and the difference remained significant even when the individual outcome groups were compared (P < 0.001). Patients who received GC within six months had a greater proportion of optimal outcome than those who received it after six months (P < 0.001).
CONCLUSIONS
Although OMG with other features is a more common subtype of OMG, it is also more severe than OMG with ptosis only. An earlier addition of GC leads to optimal outcome.
Topics: Humans; Child; Myasthenia Gravis; Blepharoptosis; Pyridostigmine Bromide; Glucocorticoids; Retrospective Studies
PubMed: 38382246
DOI: 10.1016/j.pediatrneurol.2024.01.014 -
Biomedical Chromatography : BMC Mar 2024The present study focuses on the development of a simple, rapid, specific, and stability-indicating HPLC method for the simultaneous analysis of pyridostigmine bromide...
Stability indicating reversed-phase-high-performance liquid chromatography method development and validation for pyridostigmine bromide and sodium benzoate in oral solution.
The present study focuses on the development of a simple, rapid, specific, and stability-indicating HPLC method for the simultaneous analysis of pyridostigmine bromide (PGB) and sodium benzoate (SBN) in oral liquid dosage forms. Analytical techniques should enhance sensitivity and specificity for the estimation of pharmaceutical drug products. Stress studies were conducted under various International Conference on Harmonization (ICH) conditions for evaluation. The further optimized HPLC method was validated in accordance with the current ICH guidelines. Chromatographic separation was accomplished using a mobile phase consisting of a 950:50 v/v ratio of perchloric acid buffer and acetonitrile as mobile phase-A, and 100% acetonitrile as mobile phase-B. The flow rate is 1.0 mL/min, and the injection volume is 20 μL. Detection of components was carried out at 220 nm for PGB and 228 nm for SBN. The validated HPLC method demonstrated high specificity, with linearity ranging between 24 and 72 μg/mL for PGB and 5.2-15.6 μg/mL for SBN. The correlation coefficient for both drugs exceeded 0.999. The method demonstrated high accuracy, exceeding 97%. In stress studies, PGB was found to be sensitive to alkaline stress conditions. The results reveal the successful applicability of the current method for the estimation of PGB and SBN in its marketed formulation, which can be reasonably inferred to assess other formulation systems.
Topics: Sodium Benzoate; Chromatography, High Pressure Liquid; Pyridostigmine Bromide; Acetonitriles; Chromatography, Reverse-Phase; Drug Stability
PubMed: 38081595
DOI: 10.1002/bmc.5800 -
Clinical Neurophysiology : Official... Oct 2023To investigate the electrophysiological basis of pyridostigmine enhancement of endurance performance documented earlier in patients with spinal muscular atrophy (SMA). (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To investigate the electrophysiological basis of pyridostigmine enhancement of endurance performance documented earlier in patients with spinal muscular atrophy (SMA).
METHODS
We recorded surface electromyography (sEMG) in four upper extremity muscles of 31 patients with SMA types 2 and 3 performing endurance shuttle tests (EST) and maximal voluntary contraction (MVC) measurements during a randomized, double blind, cross-over, phase II trial. Linear mixed effect models (LMM) were used to assess the effect of pyridostigmine on (i) time courses of median frequencies and of root mean square (RMS) amplitudes of sEMG signals and (ii) maximal RMS amplitudes during MVC measurements. These sEMG changes over time indicate levels of peripheral muscle fatigue and recruitment of new motor units, respectively.
RESULTS
In comparison to a placebo, patients with SMA using pyridostigmine had fourfold smaller decreases in frequency and twofold smaller increases in amplitudes of sEMG signals in some muscles, recorded during ESTs (p < 0.05). We found no effect of pyridostigmine on MVC RMS amplitudes.
CONCLUSIONS
sEMG parameters indicate enhanced low-threshold (LT) motor unit (MU) function in upper-extremity muscles of patients with SMA treated with pyridostigmine. This may underlie their improved endurance.
SIGNIFICANCE
Our results suggest that enhancing LT MU function may constitute a therapeutic strategy to reduce fatigability in patients with SMA.
Topics: Humans; Pyridostigmine Bromide; Muscular Atrophy, Spinal; Electromyography; Muscles; Muscle Fatigue; Muscle, Skeletal
PubMed: 37595479
DOI: 10.1016/j.clinph.2023.06.024 -
Journal of the American Animal Hospital... Sep 2023Acquired myasthenia gravis (MG) in dogs can present with focal or generalized weakness and is diagnosed by the presence of circulating antibodies to the acetylcholine...
Acquired myasthenia gravis (MG) in dogs can present with focal or generalized weakness and is diagnosed by the presence of circulating antibodies to the acetylcholine receptor. Megaesophagus is the most common focal form of MG. Although exacerbation of MG has been associated with the use of fluoroquinolones in humans, it has not been previously described in dogs. The medical records of 46 dogs diagnosed with MG based on acetylcholine receptor antibody testing from 1997 to 2021 were retrospectively evaluated to identify any dogs who demonstrated exacerbation of MG after the administration of a fluoroquinolone. Exacerbation of MG, from focal to generalized, occurred in a median of 4.5 days after initiation of fluoroquinolone therapy in six dogs. In addition, one dog with generalized MG and megaesophagus developed pyridostigmine resistance subsequent to fluoroquinolone therapy. Marked improvement in generalized weakness was reported 36 hr after discontinuation of fluoroquinolone therapy alone in one dog and in combination with pyridostigmine in two dogs. Fluoroquinolone therapy was never stopped in three dogs who were euthanized because of severe weakness and one dog who died of respiratory arrest.
Topics: Humans; Dogs; Animals; Pyridostigmine Bromide; Esophageal Achalasia; Retrospective Studies; Dog Diseases; Myasthenia Gravis; Fluoroquinolones; Receptors, Cholinergic
PubMed: 37708471
DOI: 10.5326/JAAHA-MS-7353