Hyperesthesia

What is Hyperesthesia?

Hyperesthesia is a term used by the International Association for the Study of Pain to describe someone feeling extra sensitive to touch, temperature, or pain. This heightened sensitivity could simply make things feel more intense, but it often results in pain when touched.

It’s a symptom often associated with a type of pain called neuropathic pain, which is a result of damage or disease affecting your body’s system responsible for feelings, like touch or temperature. When you have neuropathic pain, you might experience a range of symptoms, and hyperesthesia is one of the “positive” symptoms. These positive symptoms include pain reaction from being touched, pain that happens even without a trigger and unusual sensations, like pins and needles.

Neuropathic pain affects about 7-8% of all people. Hyperesthesia is often described as increased sensitivity to touch that leads to pain. There are two common types: allodynia and hyperalgesia. Allodynia is when harmless touch, like light touch, causes pain. Hyperalgesia is when a painful touch, like a prick, causes more pain than it should do. While most neuropathic pain symptoms stay within the area served by the damaged nerve, in some cases of hyperesthesia, the heightened sensitivity can spread beyond that area. This spread can sometimes make it difficult to accurately diagnose.

When diagnosing, your doctor will take a detailed history and perform a thorough physical examination. Standard lab tests are also generally conducted, and further specialized tests may be ordered to pinpoint the exact cause. If an underlying cause that can be treated or reversed is identified, it’ll be treated promptly. However, treatment generally focuses on relieving symptoms using medication, non-drug treatments, and medical procedures. Unfortunately, symptoms are usually hard to completely get rid of, and most patients continue to experience them. Approaching treatment with a team of healthcare professionals has been shown to give the best and most lasting results.

What Causes Hyperesthesia?

Neuropathic pain is a kind of pain that comes from problems with signals from the nerves. There are various types of these problems, including an increased sensitivity to stimuli, known as hyperesthesia, which is often caused by either a disease or damage to the nervous system leading to its improper functioning. The cause of such increased sensitivity can be traced back either due to anatomy or cause.

The problem can be peripheral (any part of the nervous system outside of the brain and spinal cord) or central (brain and spinal cord).

Peripheral causes include systemic diseases such as diabetes, nutritional deficiency, underactive thyroid, blood vessel inflammation, sarcoidosis (an inflammatory disease), certain types of cancers, Guillain-Barre syndrome (a condition in which the immune system attacks the nerves), and chronic inflammation of nerves. Other peripheral causes include infections like HIV, herpes, chickenpox, mononucleosis, West Nile virus, Hepatitis C, rabies, tuberculosis, leprosy, and Lyme disease. Furthermore, certain medications and toxins like chemotherapy drugs, cholesterol-lowering drugs, amiodarone (a heart medication), certain antibiotics, and immunosuppressants can also cause these symptoms. Physical injury, nerve compression, post-amputation pain, facial nerve pain, pain after breast surgery or back surgery, and nerve root compression are also peripheral causes. Hereditary diseases like Charcot-Marie-Tooth disease and metachromatic leukodystrophy can also cause these symptoms.

Central causes include systemic diseases like B12 deficiency leading to spinal cord disease, multiple sclerosis, strokes, excessive sensitivity to pain caused by opioid painkillers, and infections such as herpes simplex virus, myelitis (inflammation of the spinal cord), and encephalitis (inflammation of the brain). Physical conditions like spinal cord injury, tumors in the brain and spinal cord, syringomyelia (a fluid-filled cyst in the spinal cord), and myelopathy (spinal cord disease) can also cause these symptoms.

Risk Factors and Frequency for Hyperesthesia

Studies on hyperesthesia, or heightened sensitivity to stimuli, are tricky to carry out for a number of reasons. Among these reasons are the wide range of conditions that can cause hyperesthesia and the fact that it is largely based on individual perceptions. From the studies that have been done on chronic pain with features similar to that of nerve pain, the estimated prevalence of this type of pain in the general population is thought to be around 7 to 8%.

One study that used a survey to look into the sensory symptoms in people suffering from painful diabetic neuropathy (PDN) and postherpetic neuralgia (PHN) – a painful condition resulting from shingles – found that around half of the PHN patients experienced allodynia, or a heightened sensitivity to light touch. The study included 1,600 PDN patients, 18% of whom reported pain upon light touch, and 14% reported occasional pain when exposed to hot or cold temperatures.

Another study that carried out sensory testing on 1,236 patients with diagnosed nerve pain used both mechanical and thermal stimuli. The results showed:

• About 20% of patients experienced brush-provoked allodynia.
• Pain triggered by mechanical stimuli (like a pin prick or blunt pressure) occurred more frequently (29% and 36% respectively) than pain triggered by thermal stimuli (hot and cold at 24% and 19% respectively).

Signs and Symptoms of Hyperesthesia

A detailed account of one’s health history is important for diagnosing hyperesthesia, a condition that manifests as increased sensitivity to stimulation such as touch, heat, cold, or pressure.

During the consultation, the physician will ask about:

• Past medical history, such as diabetes, stroke, fractures, irritable bowel syndrome
• Mental health history related to mood disorders
• Any medication use, particularly those that could harm nerve cells
• Past surgical procedures
• Family medical history
• Sexual history
• Substance use involving alcohol or opioids
• The impact of the symptoms on daily life, work, or sleep

The clinician will also gather a thorough description of the patient’s pain symptoms. This includes the location of the pain, its intensity, what it feels like, when it occurred and if it was triggered by something specific. The doctor might inquire about patterns such as whether the pain is worse at certain times of day, whether it increases or decreases depending on the body’s position, and if it spreads or originates from the spine.

A physical examination is also conducted. Initially, a general examination of overall health is conducted, followed by a thorough neurological assessment:

• Testing of cranial nerves, as central nervous system lesions may involve these nerves
• Manual motor testing, since weakness can occur in both peripheral and central conditions
• Test of deep tendon reflexes, as they may be pronounced in central disorders but reduced in peripheral diseases
• Sensory tests such as assessments for light touch, pinprick sensations, vibrations, and sense of position
• Temperature assessment through the application of ice and hot packs
• Straight leg or slump tests to evaluate nerve pain originating from the spinal cord
• Performing Tinel’s sign to assess trapped peripheral nerves
• Looking for trigger points in your muscles for localised pain issues

In cases of complex regional pain syndrome (CRPS), a skin examination would be required to look for changes in skin temperature, colour, sweat, scars, and hair distribution.

Testing for Hyperesthesia

The first thing we need to do is figure out whether your hyperesthesia, or increased sensitivity to touch, is coming from an issue in your peripheral nervous system (nerves throughout your body) or your central nervous system (brain and spinal cord). Correctly identifying the source will help us treat any underlying causes that we might be able to address.

Lab Tests

Various lab tests can become a part of a regular check-up to investigate peripheral hyperesthesia, which includes: complete blood count, comprehensive metabolic panel, fasting blood glucose, erythrocyte sedimentation rate (a test checking for inflammation in your body), thyroid stimulating hormone, and vitamin B12 levels.

If the doctor suspects certain other conditions based on your symptoms, you might undergo further tests such as Hemoglobin A1c (a test for diabetes), HIV antibodies, liver panel, Lyme disease antibodies, Rapid Plasma Reagin (a test for syphilis), urinalysis, urine protein electrophoresis, serum protein electrophoresis, angiotensin-converting enzyme levels (a test primarily for sarcoidosis, a type of lung disease), antinuclear antibody (a test for autoimmune disorders), perinuclear anti-neutrophil cytoplasmic antibodies test and cytoplasmic antineutrophil cytoplasmic antibodies test (both are specific tests for types of autoimmune disorders).

In rare cases, tests may be ordered for specific conditions. These could include a paraneoplastic panel (tests looking for cancer), antimyelin associated glycoprotein, antiganglioside antibodies (tests for certain types of nerve disease), salivary flow rate, and genetic testing. Moreover, cerebrospinal fluid analysis can also be performed (this is a test of the fluid that surrounds your brain and spinal cord).

Imaging

Imaging is usually not necessary to diagnose hyperesthesia, although it can help determine the cause. Computed tomography (CT) scans and magnetic resonance imaging (MRI) may be used if nerve root compression, herniated disc, myelopathy (spinal cord injury), or a tumor in the brain or spinal cord is suspected. A triple-phase bone scan could be used to support a diagnosis of Complex Regional Pain Syndrome (CRPS), a chronic pain condition.

Special Tests

Electrodiagnostics may be performed including electromyography and nerve conduction studies. However, these tests primarily examine large nerve fibers. Punch skin biopsy may be performed, which helps identify small-fiber neuropathy, a condition that affects the small fibers of the nervous system.

Treatment Options for Hyperesthesia

Treating hyperesthesia and other types of nerve pain can be tricky. That’s why it’s best to have a team of healthcare providers working together. This team can focus on treating the root causes of the pain, managing symptoms with pain medication, use interventions like physical therapy, address any physical impairments you may have and provide mental health services if needed.

The team should aim to set realistic goals for tackling your nerve pain and any related conditions, like mood disorders or sleep issues, should also be addressed. It’s crucial to check in frequently with your treatment team to gauge how well your treatment is working and if the root cause of your condition needs continued evaluation.

If your nerve pain is caused by a disorder in the peripheral nervous system, some common treatable causes include diabetes, underactive thyroid (hypothyroidism), and nutritional deficiencies. There are other causes too, like nerve root compression (nerve pinched by surrounding tissues) or peripheral nerve entrapment (nerve trapped in a tight space), which might initially be managed less invasively with support through pain medication, physical therapy, lifestyle changes, and minimally invasive procedures (such as epidural steroid injection or peripheral nerve injection). If your functionality continues to worsen or plateau, surgery might be needed.

There’s a range of pharmacological treatments that can be used to manage hyperesthesia whether it arises from central or peripheral causes. Typically, the most common drugs used are antidepressants and antiepileptic drugs. Each individual will respond differently, so it’s important to consult with your healthcare provider for the best solution.

Top recommended drugs are antidepressants and antiepileptic drugs, which have been shown to significantly help with nerve pain symptoms. In addition to pain relief, antidepressants can also address any co-existing mood disorders. Antidepressants from groups like ‘tricyclic antidepressants’ and ‘serotonin-norepinephrine reuptake inhibitors’, and antiepileptic drugs like ‘gabapentinoids’ are widely used.

If first-line treatment is not effective, there are also second-line and third-line treatments available. These comprise of topical medications like Lidocaine and Capsaicin patches, a non-specific pain killer called Tramadol, and stronger opioids. There is also the use of Botulinum toxin-A in some cases. Patient symptoms vary and no single treatment will help everyone, so combining multiple medicines is common.

Besides medication, there are also different interventional therapies like epidural steroid injections, sympathetic nerve block, neurostimulation (including spinal cord and motor cortex stimulation), and transcutaneous electrical nerve stimulation (or TENS; method of pain relief involving the use of a mild electrical current). Some of these treatments are still being researched for their effectiveness, so it’s important to discuss these options with your healthcare team and understand their benefits and risks.

What else can Hyperesthesia be?

There are several conditions that can be the source of chronic pain. These include:

• Nociceptive pain (pain that comes from damage to physical tissues)
• Myofascial pain syndrome (chronic pain involving the muscles and the tissues that support them)
• Fibromyalgia (a condition causing widespread pain throughout the body)
• Chronic fatigue syndrome (a disorder characterized by extreme tiredness)

What to expect with Hyperesthesia

It can be challenging to fully get rid of extremely sensitive skin sensations and other symptoms related to nerve pain, also known as neuropathic pain. It’s essential for patients to understand this early in their treatment so they have realistic expectations. Usually, treatment should begin with only one type of medication; however, almost half of all patients with nerve pain end up taking two or more different drugs to manage their pain.

Possible Complications When Diagnosed with Hyperesthesia

The complications arising from hyperesthesia, or extreme sensitivity to touch, can increase illness if not managed properly. The patient might also experience this increased illness from undergoing complex treatment procedures. Beginning treatment with powerful painkillers, like opioids, can also lead to addiction.

Common Complications:

• Increased health issues if symptoms are not controlled
• Increased health issues from complex treatment procedures
• Potential addiction if started on powerful painkillers like opioids

Preventing Hyperesthesia

Here are some key things to remember:

* Setting realistic expectations is a crucial step in your treatment plan. Symptoms like hyperesthesia (a condition where you may feel an overreaction to touch or pain) and other types of nerve pain can be tough to manage and likely will not go away completely. This is something that should be talked about early on in the treatment course.

* Working with a team of various healthcare professionals can be beneficial in managing symptoms like hyperesthesia and other kinds of nerve pain. This approach tends to offer the best pain relief results.

* The treatment plan should be followed in a step-by-step manner.

* Medical procedures may be an option for patients who don’t find enough relief from medication or wish to decrease the use of high-risk medications like opioids (a type of strong painkiller that can lead to addiction).

* Managing other existing health conditions is important too. This may include emotional health conditions like mood disorders and sleep disturbances.

The healthcare team should communicate with you on a regular basis regarding your current treatment plan and possible future treatments. This makes certain that you’re well-informed and involved in your own healthcare.