Peripheral neuropathy is a disorder of the peripheral nervous system that associates a series of manifestations that cause muscle weakness, numbness and pain syndrome in the upper and lower limbs.
What is peripheral neuropathy?
What are the causes of peripheral neuropathy?
Symptoms of peripheral neuropathy
The diagnosis of peripheral neuropathy
Treatment of peripheral neuropathy
What is peripheral neuropathy?
Peripheral neuropathy is a disorder of the peripheral nervous system that associates a series of manifestations that cause muscle weakness, numbness and algic syndrome (pain) in the upper and lower limbs.
What are the causes of peripheral neuropathy?
Peripheral neuropathy is determined by damage to the nerve endings in the upper and lower limbs caused by trauma (compressive, sectional trauma), metabolic imbalances, infections or exposure to toxins. The most common etiology of peripheral polyneuropathy is encountered in medical practice in the case of patients diagnosed with diabetes. Genetic peripheral neuropathy is a rare form of disease favored by certain genetic mutations that determine the appearance of the Charcot Marie Tooth condition.
Traumatic damage to the nerve endings found in the upper and lower limbs can occur as a result of road accidents, nerve compression due to the development of malignant or benign tumor processes, compartment syndrome (nerve compression is due to the redistribution of interstitial fluid in the various anatomical compartments of the hand or leg) or post-surgical.
In certain situations, damage to the nerve endings can occur following chemotherapy treatment specific to tumor pathologies with various locations. Infections with Epstein Barr, hepatitis C virus, HIV or those that cause Lyme disease and zoster are other factors that can cause the appearance of peripheral neuropathies. Other causes involved in the occurrence of acquired peripheral neuropathies are represented by excessive alcohol consumption, poor diet or lack of vitamin intake.
Symptoms of peripheral neuropathy
The symptoms that make up the clinical picture of patients with peripheral neuropathy vary from case to case depending on the type of condition as follows:
- Mononeuropathy affects a single nerve and causes the appearance of unilateral paresthesias in the anatomical territory served by it, being found in carpal tunnel syndrome, paralysis of the ulnar, radial or peroneal nerve
- Multiple mononeuropathy is due to the damage of more than 2 nerve roots and can sometimes sequentially involve several nerve structures, bearing the name of multiplex mononeuropathy
- Polyneuropathy is a generalized disorder of peripheral innervation frequently encountered in diabetics (diabetic neuropathy) and in Guillan Barre syndrome
- The condition begins progressively in the vast majority of cases and causes the sensation of numbness in the hand or foot, known as “numbness in the glove or in the sock”, the unilateral or bilateral nature of the symptoms is given by the number of nerve pathways affected – mono or polyneuropathy. In addition to paresthesia, the sensory manifestations of peripheral neuropathy also include tactile sensitivity in the affected limb, intense pain that has a burning, throbbing or throbbing character (stabbing sensation)
The motor manifestations of peripheral neuropathy are represented by muscle weakness in the affected limb, which causes difficulty in coordinating movements and loss of balance, along with muscle cramps and muscle atrophy.
Affecting the autonomic nerves in the evolution of peripheral neuropathies causes sweating, heightened thermal sensitivity at high temperatures, changes in blood pressure and urinary and/or fecal incontinence.
The diagnosis of peripheral neuropathy
Due to the multifactorial etiology, the diagnosis of neuropathies is sometimes difficult to perform, but it can be established with the help of the anamnesis and the detailed neurological clinical examination of the patient, followed by the performance of paraclinical investigations represented by:
- An electromyogram (EMG) is used to identify sensory, motor or autonomic neuropathies; the investigation can specify the axonal or demyelinating type of lesion, the distribution of the lesions and the progression of the disease
- Laboratory analyses confirm the etiology of peripheral neuropathies by identifying metabolic disorders (diabetes), thyroid hypofunction, autoimmune pathologies (Sjogren’s syndrome, systemic lupus erythematosus, rheumatoid arthritis), infections (borreliosis, hepatitis, HIV) and poisoning through accidental exposure to toxic substances
Treatment of peripheral neuropathy
The etiological treatment of peripheral neuropathies addresses the underlying pathologies that favor the appearance of specific manifestations and may include hormone replacement in the case of thyroid hypofunction, antidiabetics and/or insulin for the treatment of diabetes, excision and surgical decompression in the case of tumors, antibiotics or systemic antivirals for the remission of bacterial infections or viral.
Symptomatic therapy aims to reduce the specific manifestations of peripheral neuropathy with the help of anti-inflammatory drugs, tricyclic antidepressants or anticonvulsants. Neuromodulatory therapy uses spinal cord stimulators and electrotherapy to improve sensory and motor function in the affected peripheral segments.
Find out more:
- Epidemiology of peripheral neuropathy. – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1074084/
- Management of Diabetic Peripheral Neuropathy – https://diabetesjournals.org/clinical/article/23/1/9/1269/Management-of-Diabetic-Peripheral-Neuropathy
- Advances in the epidemiology, pathogenesis and management of diabetic peripheral neuropathy – https://onlinelibrary.wiley.com/doi/full/10.1002/dmrr.2239
