Peripheral Neuritis: Symptoms, Types, Causes and Treatment

Peripheral neuritis—often referred to as peripheral neuropathy or polyneuritis—is a condition that affects the peripheral nerves, which are responsible for transmitting information between the central nervous system and the rest of the body. This article offers a comprehensive overview of the symptoms, types, causes, and treatment options for peripheral neuritis, drawing on the latest research and clinical insights.

Symptoms of Peripheral Neuritis

Peripheral neuritis can manifest in a variety of ways depending on the nerves affected and the underlying cause. The symptoms are often sensory, but motor and autonomic nerves can also be involved. Recognizing these symptoms early is key to effective management and improved quality of life.

Symptom	Description	Impact/Location	Source(s)
Pain	Burning, stabbing, throbbing, or sharp	Limbs, hands, feet	1, 11
Numbness	Reduced or lost sensation	Hands, feet	11
Tingling	Pins-and-needles sensation	Extremities	11
Muscle Weakness	Difficulty moving or controlling muscles	Arms, legs	11, 5
Allodynia	Pain from non-painful stimuli	Skin	1
Temperature Sensitivity	Unusual response to heat/cold	Skin	1
Balance Issues	Dizziness, instability	Whole body	2

Table 1: Key Symptoms

Understanding the Range of Symptoms

Peripheral neuritis doesn't present the same way in every person. Symptoms can develop suddenly or gradually and often vary in their intensity and distribution.

Sensory Symptoms

• Pain: Neuropathic pain is a hallmark, with patients describing sensations such as burning, stabbing, or sharp pain. These may be spontaneous or triggered by normally innocuous stimuli—a phenomenon known as allodynia. Some also experience hyperalgesia, where even mild discomfort is perceived as severe pain 1.
• Numbness and Tingling: Many patients report numbness or a “pins-and-needles” sensation, commonly starting in the toes or fingers and potentially spreading up the limbs 11.
• Temperature Sensitivity: Some experience heightened sensitivity to heat or cold, or paradoxically, an impaired ability to detect temperature changes 1.

Motor Symptoms

• Muscle Weakness: When motor nerves are affected, muscle weakness or even paralysis can develop. This can make everyday tasks, like walking or holding objects, challenging 11, 5.
• Loss of Coordination: Muscle weakness may be accompanied by poor coordination and balance issues, increasing the risk of falls 2.

Autonomic Symptoms

• Balance and Dizziness: Certain types, such as vestibular neuritis, can lead to loss of balance and vertigo due to involvement of the nerves responsible for equilibrium 2.
• Other Autonomic Features: Although less common, some forms can affect sweating, blood pressure regulation, or bladder and bowel function 5.

Types of Peripheral Neuritis

Peripheral neuritis is not a single disease, but a group of disorders classified by the pattern of nerve involvement, underlying pathology, and affected nerve types. Understanding these distinctions helps tailor diagnosis and management.

Type	Description	Distinguishing Feature	Source(s)
Polyneuritis	Multiple nerves, symmetrical	Both sides affected	5, 8
Mononeuritis	Single nerve involvement	Localized symptoms	5
Mononeuritis Multiplex	Several individual nerves, asymmetric	Patchy, multifocal deficits	5
Vestibular Neuritis	Affects balance nerve	Vertigo, imbalance	2
Brachial Neuritis	Affects brachial plexus	Arm/shoulder pain, weakness	3
Neuritis Ossificans	Nerve involvement with ossification	Hard mass, local symptoms	4

Table 2: Major Types

Classification by Nerve Distribution

• Polyneuritis (Polyneuropathy): The most common form, involving multiple nerves symmetrically. Symptoms usually start in the extremities and progress proximally. Common causes include diabetes, toxins, and systemic diseases 5, 8.
• Mononeuritis: Involves a single nerve, leading to localized deficits. Trauma, compression, or entrapment (e.g., carpal tunnel syndrome) are typical culprits 5.
• Mononeuritis Multiplex: Several individual nerves are affected in a patchy, asymmetric pattern. Often associated with vasculitis or autoimmune diseases 5.

Special Types

• Vestibular Neuritis: Involves the vestibular nerve, leading to severe vertigo, dizziness, and balance problems. While static symptoms (vertigo, nystagmus) typically resolve, dynamic symptoms (impaired reflexes) may persist 2.
• Brachial Neuritis: Targets nerves of the brachial plexus, causing acute shoulder/arm pain followed by weakness. Sometimes seen in autoimmune or inflammatory conditions 3.
• Neuritis Ossificans: A rare condition where ossification (bone formation) occurs within a peripheral nerve, often leading to a palpable mass and significant local symptoms. Trauma is suspected but not always evident 4.

Classification by Underlying Process

• Inflammatory Neuritis: Involves immune-mediated or infectious processes, as in Guillain-Barré syndrome or post-infectious neuropathies 3, 8.
• Ischemic Neuritis: Resulting from impaired blood supply to the nerves, often due to vascular disease or arterial occlusion 7.
• Toxic Neuritis: Caused by exposure to toxins, drugs, or metabolic byproducts 8.

Causes of Peripheral Neuritis

The causes of peripheral neuritis are diverse and sometimes multifactorial. Identifying the underlying etiology is critical for effective management and prevention of recurrence.

Cause	Examples/Details	Notable Features	Source(s)
Toxins/Drugs	Alcohol, lead, certain medications, tri-orthocresyl phosphate	Often preventable/toxic exposures	8
Metabolic Disorders	Diabetes, vitamin deficiencies (esp. B vitamins)	Chronic onset, treatable	5, 8
Autoimmune Diseases	Rheumatoid arthritis, vasculitis, MOG antibody disease	May be relapsing/remitting	6, 3, 5
Infections	Diphtheria, viral (e.g., herpes zoster)	Acute onset, often reversible	8, 1
Ischemia/Vascular	Arteriosclerosis, embolism, infarction, periarteritis nodosa	Associated with vascular disease	7, 5
Trauma/Compression	Physical injury, repetitive use, entrapment	Localized, often sudden	11, 4
Idiopathic	Unknown or spontaneous onset	Diagnosis of exclusion	8

Table 3: Major Causes

Toxic and Metabolic Factors

• Exogenous Toxins: Chronic alcohol use, lead, and certain drugs can damage peripheral nerves. Historic outbreaks (e.g., "Jake Leg" paralysis from adulterated Jamaica Ginger) underscore the dangers of contaminated products 8.
• Metabolic Disorders: Diabetes is a leading cause, with chronic high blood sugar damaging nerves over time. Vitamin deficiencies, especially of the B vitamins, are also implicated 5, 8.

Autoimmune and Inflammatory Causes

• Rheumatoid Arthritis and Vasculitis: Inflammatory disorders can cause immune-mediated attacks on nerves, resulting in both sensory and motor deficits 6, 5.
• MOG Antibody Disease: Recent research links myelin oligodendrocyte glycoprotein (MOG) antibodies to episodes of peripheral neuritis, particularly when associated with demyelinating diseases 3.

Infectious Agents

• Bacterial and Viral Infections: Certain infections, such as diphtheria and herpes zoster (shingles), can directly damage peripheral nerves, often resulting in acute symptoms 8, 1.

Vascular and Ischemic Causes

• Impaired Blood Supply: Conditions that reduce blood flow to nerves, such as arteriosclerosis, embolism, or periarteritis nodosa, can lead to ischemic neuritis 7, 5.
• Trauma and Compression: Direct injuries, repetitive strain, or compression (e.g., carpal tunnel) are common causes of localized neuritis 11, 4.

Idiopathic Cases

• In some cases, no clear cause can be identified—these are termed idiopathic. They may result from subtle or unrecognized insults 8.

Treatment of Peripheral Neuritis

Treating peripheral neuritis requires a multifaceted approach, tailored to the underlying cause and dominant symptoms. While some cases can be resolved with appropriate interventions, others may require ongoing management.

Treatment	Approach/Examples	Indication/Notes	Source(s)
Pharmacotherapy	SNRIs (duloxetine, venlafaxine), gabapentin, TCAs, pregabalin	First-line for neuropathic pain	9, 10, 13
Topical Treatments	Lidocaine 5% patch, capsaicin 8% patch	For localized neuropathic pain	13, 9
Immunotherapy	Corticosteroids, rituximab, fingolimod	Autoimmune/inflammatory neuritis	3, 12
Physical Therapy	Vestibular rehab, exercise	Improve function, balance	2, 11
Surgical/Interventional	Nerve decompression, neurostimulation	Refractory or compressive cases	11, 9, 10
Psychotherapy	CBT, mindfulness	Adjunct for chronic pain	9
Treat Underlying Cause	Address diabetes, remove toxins, treat infection	Essential for long-term success	5, 8, 6

Table 4: Main Treatments

Pharmacological Treatments

• First-line Medications: Serotonin-norepinephrine reuptake inhibitors (SNRIs, e.g., duloxetine, venlafaxine), gabapentinoids (gabapentin, pregabalin), and tricyclic antidepressants (TCAs) are strongly recommended as initial therapies for neuropathic pain 9, 10.
• Topical Agents: Lidocaine 5% patches and capsaicin 8% patches are effective for certain types, with fewer systemic side effects. These may be used as first-line agents in select cases, especially when oral medications are not tolerated 13, 9.
• Second/Third-line Options: Options such as tramadol, strong opioids (as a last resort), and interventional techniques (e.g., spinal cord stimulation) are considered when initial treatments fail 9, 10.

Immunotherapy and Disease-Modifying Treatments

• Steroids and Biologics: In autoimmune-related neuritis, such as those associated with MOG antibodies, high-dose corticosteroids and agents like rituximab may lead to rapid improvement 3.
• Novel Agents: Fingolimod has demonstrated promise in experimental models of autoimmune neuritis, providing immunomodulatory and neuroprotective effects 12.

Physical and Supportive Therapies

• Physical Rehabilitation: Physical therapy is crucial to maintain strength, flexibility, and balance, particularly following acute events such as vestibular neuritis or traumatic nerve injury 2, 11.
• Psychological Support: Chronic pain and disability often necessitate cognitive behavioral therapy (CBT) or mindfulness as adjuncts 9.

Addressing Underlying Causes

• Metabolic Control: Tight glucose control in diabetes, vitamin supplementation for deficiencies, and cessation of alcohol or toxin exposure are fundamental steps 5, 8.
• Infection and Vascular Management: Prompt treatment of infections and optimization of vascular health are important in relevant cases 5, 7.

Surgical and Interventional Approaches

• Nerve Decompression/Resection: In select cases with compressive lesions or masses (e.g., neuritis ossificans), surgery may be required 4, 11.
• Neurostimulation: Techniques like transcutaneous electrical nerve stimulation (TENS) and spinal cord stimulation have a role in refractory pain management 9, 10.

Conclusion

Peripheral neuritis is a complex and multifaceted group of disorders that demand a nuanced understanding of their symptoms, types, causes, and treatment options. Early recognition and a comprehensive, individualized approach can significantly improve outcomes and quality of life.

Key Points:

• Peripheral neuritis produces a spectrum of symptoms ranging from pain and numbness to weakness and balance disturbances 1, 2, 11.
• Types include polyneuritis, mononeuritis, mononeuritis multiplex, and special forms such as vestibular neuritis and neuritis ossificans 5, 2, 4.
• Causes are varied, encompassing toxins, metabolic diseases, autoimmune and infectious processes, vascular disorders, trauma, and idiopathic origins 8, 5, 7, 3.
• Treatment is cause-specific and symptom-driven, involving pharmacological, topical, immunological, physical, surgical, and psychological strategies 9, 10, 13, 11, 12, 3.
• A multidisciplinary and patient-centered approach is essential for optimal management and rehabilitation.