Shouman, Kamal

Autonomic medicine is a rapidly evolving field focused on understanding diseases and processes that affect the autonomic nervous system (ANS). The ANS regulates essential involuntary physiologic processes such as heart rate, blood pressure, and digestion. This review introduces the key anatomical structures, physiological mechanisms, and biochemical processes underlying autonomic function. The anatomy section focuses on the peripheral components of the ANS, including the sympathetic and parasympathetic divisions. The physiological section explores the process of homeostasis and the intricate feedback systems that maintain this balance within the body. Finally, the biochemistry of autonomic signaling, focusing on the neurotransmitters acetylcholine, norepinephrine, and epinephrine, and their receptors, is reviewed. Pertinent clinical points are highlighted throughout, emphasizing the importance of the basic science to the clinical world. This review aims to provide a comprehensive basic science foundation for clinicians and researchers exploring the field of autonomic medicine.

Abstract Introduction/Aims Carpal and cubital tunnel syndrome (CTS, CuTS) are common among patients with hereditary neuropathy with liability to pressure‐palsies (HNPP) and Charcot–Marie‐Tooth type 1A (CMT1A) and may impact quality of life. We aimed to evaluate the utility of nerve decompression surgeries in these patients. Methods Medical records were reviewed for patients with PMP22 mutations confirmed in Mayo Clinic laboratories from January 1999 to December 2020, who had CTS and CuTS and underwent surgical decompression. Results CTS occurred in 53.3% of HNPP and 11.5% of CMT1A, while CuTS was present in 43.3% of HNPP and 5.8% of CMT1A patients. CTS decompression occurred in 10‐HNPP and 5‐CMT1A patients, and CuTS decompression with/without transposition was performed in 5‐HNPP and 1‐CMT1A patients. In HNPP, electrodiagnostic studies identified median neuropathy at the wrist in 9/10 patients and ultrasound showed focal enlargements at the carpal and cubital tunnels. In CMT1A, median and ulnar sensory responses were all absent, and the nerves were diffusely enlarged. After CTS surgery, pain, sensory loss, and strength improved in 4/5 CMT1A, and 6/10 HNPP patients. Of clinical, electrophysiologic and ultrasound findings, only activity‐provoked features significantly correlated with CTS surgical benefit in HNPP patients (odds ratio = 117.0:95% confidence interval, 1.94 > 999.99, p = 0.01). One CMT1A and one HNPP patient improved with CuTS surgery while 2 HNPP patients worsened. Discussion CTS symptom improvement post‐surgery can be seen in CMT1A and (less frequent) in HNPP patients. CuTS surgery commonly worsened course in HNPP. Activity‐provoked symptoms in HNPP best informed benefits from CTS surgery.

AbstractIntroduction/AimsRecently, our group found an association between diabetes mellitus (DM) and lumbosacral radiculoplexus neuropathy (LRPN) in Olmsted County, Minnesota; we found a higher risk (odds ratio [OR], 7.91) for developing LRPN in diabetic compared with nondiabetic patients. However, the influence of other comorbidities and anthropomorphic variables was not studied.MethodsDemographic and clinical data from 59 LRPN patients and 177 age/sex‐matched controls were extracted using the Rochester LRPN epidemiological study. Differences between groups were compared by chi‐square/Fisher exact test or Wilcoxon rank‐sum test. Uni‐ and multivariate logistic regression analysis were performed.ResultsFactors predictive of LRPN on univariate analysis were DM (OR, 7.91; 95% confidence interval [CI], 4.11‐15.21), dementia (OR, 6.36; 95% CI, 1.13‐35.67), stroke (OR, 3.81; 95% CI, 1.32‐11.01), dyslipidemia (OR, 2.844; 95% CI, 1.53‐5.27), comorbid autoimmune disorders (OR, 2.72; 95% CI, 1.07‐6.93), hypertension (OR, 2.25; 95% CI, 1.2‐4.13), obesity (OR, 2.05; 95% CI, 1.11–3.8), body mass index (BMI) (OR, 1.1; 95% CI, 1.04‐1.15), and weight (OR, 1.02; 95% CI, 1.009‐1.037). On multivariate logistic regression analysis only DM (OR, 8.03; 95% CI, 3.86‐16.7), comorbid autoimmune disorders (OR, 4.58; 95% CI, 1.45‐14.7), stroke (OR, 4.13; 95% CI, 1.2‐14.25), and BMI (OR, 1.07; 95% CI, 1.01‐1.13) were risk factors for LRPN.DiscussionDM is the strongest risk factor for the development of LRPN, followed by comorbid autoimmune disorders, stroke, and higher BMI. Altered metabolism and immune dysfunction seem to be the most influential factors in the development of LRPN.

AbstractBackgroundMultiple mononeuropathy is a rare presentation of primary (AL) amyloidosis and nerve biopsy is usually needed for diagnosis. Conventional imaging is useful to identify proximal nerve involvement but may be inadequate. We report a patient with multiple mononeuropathy whose presentation was suggestive of AL amyloid neuropathy and in whom repeated tissue biopsies were negative for amyloid (including two sensory nerves and one muscle).MethodsThe patient underwent magnetic resonance imaging (MRI) and whole body 18F‐florbetapir positron emission tomography (PET)/MRI.ResultsWhole body 18F‐florbetapir PET/MRI revealed abnormal low‐level florbetapir uptake in the right proximal tibial and peroneal nerves, which provided a target for a sciatic bifurcation fascicular nerve biopsy that was diagnostic of AL amyloidosis.Conclusions 18F‐florbetapir PET/MRI imaging is a promising diagnostic tool for patients with suspected peripheral nerve amyloidosis (including multiple mononeuropathy) in whom conventional imaging and nerve and muscle biopsies miss the pathology.