Paresthesia in the context of Hypoesthesia

Poliomyelitis (/ˌpoʊlioʊˌmaɪəˈlaɪtɪs/ POH-lee-oh-MY-ə-LY-tiss), commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 75% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe symptoms develop such as headache, neck stiffness, and paresthesia. These symptoms usually pass within one or two weeks. A less common symptom is permanent paralysis, and possible death in extreme cases. Years after recovery, post-polio syndrome may occur, with a slow development of muscle weakness similar to what the person had during the initial infection.

Polio occurs naturally only in humans. It is highly infectious, and is spread from person to person either through fecal–oral transmission (e.g. poor hygiene, or by ingestion of food or water contaminated by human feces), or via the oral–oral route. Those who are infected may spread the disease for up to six weeks even if no symptoms are present. The disease may be diagnosed by finding the virus in the feces or detecting antibodies against it in the blood.

Shingles, also known as herpes zoster or zona, is a viral disease characterized by a painful skin rash with blisters in a localized area. Typically the rash occurs in a single, wide mark either on the left or right side of the body or face. Two to four days before the rash occurs, there may be tingling or local pain in the area. Other common symptoms are fever, headache, and tiredness. The rash usually heals within two to four weeks, but some people develop ongoing nerve pain which can last for months or years, a condition called postherpetic neuralgia (PHN). In those with poor immune function the rash may occur widely. If the rash involves the eye, vision loss may occur.

Shingles is caused by the varicella zoster virus (VZV) that also causes chickenpox. In the case of chickenpox, also called varicella, the initial infection with the virus typically occurs during childhood or adolescence. Once the chickenpox has resolved, the virus can remain dormant (inactive) in human nerve cells (dorsal root ganglia or cranial nerves) for years or decades, after which it may reactivate and travel along nerve bodies to nerve endings in the skin, producing blisters. During an outbreak of shingles, exposure to the varicella virus found in shingles blisters can cause chickenpox in someone who has not yet had chickenpox, although that person will not suffer from shingles, at least on the first infection. How the virus remains dormant in nerve cells or subsequently re-activates is not well understood.

Deities in ancient Mesopotamia were almost exclusively anthropomorphic. They were thought to possess extraordinary powers and were often envisioned as being of tremendous physical size. The deities typically wore melam, an ambiguous substance which "covered them in terrifying splendor" and which could also be worn by heroes, kings, giants, and even demons. The effect that seeing a deity's melam has on a human is described as ni, a word for the "physical creeping of the flesh". Both the Sumerian and Akkadian languages contain many words to express the sensation of ni, including the word puluhtu, meaning "fear". Deities were almost always depicted wearing horned caps, consisting of up to seven superimposed pairs of ox-horns. They were also sometimes depicted wearing clothes with elaborate decorative gold and silver ornaments sewninto them.

The ancient Mesopotamians believed that their deities lived in Heaven, but that a god's statue was a physical embodiment of the god himself. As such, cult statues were given constant care and attention and a set of priests were assigned to tend to them. These priests would clothe the statues and place feasts before them so they could "eat". A deity's temple was believed to be that deity's literal place of residence. The gods had boats, full-sized barges which were normally stored inside their temples and were used to transport their cult statues along waterways during various religious festivals. The gods also had chariots, which were used for transporting their cult statues by land. Sometimes a deity's cult statue would be transported to the location of a battle so that the deity could watch the battle unfold. The major deities of the Mesopotamian pantheon were believed to participate in the "assembly of the gods", through which the gods made all of their decisions. This assembly was seen as a divine counterpart to the semi-democratic legislative system that existed during the Third Dynasty of Ur (c. 2112 BC – c. 2004 BC).

Postherpetic neuralgia (PHN) is neuropathic pain that occurs due to damage to a peripheral nerve caused by the reactivation of the varicella zoster virus (herpes zoster, also known as shingles). PHN is defined as pain in a dermatomal distribution that lasts for at least 90 days after an outbreak of herpes zoster. Several types of pain may occur with PHN including continuous burning pain, episodes of severe shooting or electric-like pain, and a heightened sensitivity to gentle touch which would not otherwise cause pain or to painful stimuli. Abnormal sensations and itching may also occur.

Postherpetic neuralgia is the most common long-term complication of herpes zoster, and occurs in approximately 20% of patients with shingles. Risk factors for PHN include older age, severe prodrome or rash, severe acute zoster pain, ophthalmic involvement, immunosuppression, and chronic conditions such as diabetes mellitus and lupus. The pain from postherpetic neuralgia can be very severe and debilitating. There is no treatment which modifies the course of the disease and management primarily aims to control symptoms. Affected individuals often experience a decrease in their quality of life.

Lead poisoning, also known as plumbism and saturnism, is a type of metal poisoning caused by the presence of lead in the human body. Symptoms of lead poisoning may include abdominal pain, constipation, headaches, irritability, memory problems, infertility, numbness and tingling in the hands and feet. Lead poisoning causes almost 10% of intellectual disability of otherwise unknown cause and can result in behavioral problems. Some of the effects are permanent. In severe cases, anemia, seizures, coma, or death may occur.

Exposure to lead can occur through contaminated air, water, dust, food, or consumer products. Lead poisoning poses a significantly increased risk to children and pets as they are far more likely to ingest lead indirectly by chewing on toys or other objects that are coated in lead paint. Additionally, children absorb greater quantities of lead from ingested sources than adults. Exposure at work is a common cause of lead poisoning in adults, with certain occupations at particular risk. Diagnosis is typically by measurement of the blood lead level. The Centers for Disease Control and Prevention (US) has set the upper limit for blood lead for adults at 10 μg/dL (10 μg/100 g) and for children at 3.5 μg/dL; before October 2021 the limit was 5 μg/dL. Elevated lead may also be detected by changes in red blood cells or dense lines in the bones of children as seen on X-ray.

Obdormition (/ˌɒbdɔːrˈmɪʃən/; from Latin obdormire "to fall asleep") is a medical term describing temporary numbness in a limb, often caused by constant pressure on nerves or lack of movement. This is colloquially referred to as the limb "going to sleep," and it is usually followed by paresthesia, colloquially called "pins and needles".

Formication is the sensation resembling that of small insects crawling on (or under) the skin, in the absence of actual insects. It is one specific form of a set of sensations known as paresthesias, which also include the more common prickling, tingling sensation known as pins and needles. Formication is a well-documented symptom which has numerous possible causes. The word is derived from formica, the Latin word for ant.

Formication may sometimes be experienced as feelings of itchiness, tingling, pins and needles, burning, or even pain. When formication is perceived as itchiness, it may trigger the scratch reflex, and, because of this, some people who experience the sensation are at risk of causing skin damage through excessive scratching.

Hyperkalemia is an elevated level of potassium (K) in the blood. Normal potassium levels are between 3.5 and 5.0 mmol/L (3.5 and 5.0 mEq/L) with levels above 5.5 mmol/L defined as hyperkalemia. Typically hyperkalemia does not cause symptoms. Occasionally when severe it can cause palpitations, muscle pain, muscle weakness, or numbness. Hyperkalemia can cause an abnormal heart rhythm which can result in cardiac arrest and death.

Common causes of hyperkalemia include kidney failure, hypoaldosteronism, and rhabdomyolysis. A number of medications can also cause high blood potassium including mineralocorticoid receptor antagonists (e.g., spironolactone, eplerenone and finerenone) NSAIDs, potassium-sparing diuretics (e.g., amiloride), angiotensin receptor blockers, and angiotensin converting enzyme inhibitors. The severity is divided into mild (5.5 – 5.9 mmol/L), moderate (6.0 – 6.5 mmol/L), and severe (> 6.5 mmol/L). High levels can be detected on an electrocardiogram (ECG), though the absence of ECG changes does not rule out hyperkalemia. The measurement properties of ECG changes in predicting hyperkalemia are not known. Pseudohyperkalemia, due to breakdown of cells during or after taking the blood sample, should be ruled out.

Hypocalcemia is a medical condition characterized by low calcium levels in the blood serum. The normal range of blood calcium is typically between 2.1–2.6 mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L), while levels less than 2.1 mmol/L are defined as hypocalcemic. Mildly low levels that develop slowly often have no symptoms. Otherwise symptoms may include numbness, muscle spasms, seizures, confusion, or in extreme cases cardiac arrest.

The most common cause for hypocalcemia is iatrogenic hypoparathyroidism. Other causes include other forms of hypoparathyroidism, vitamin D deficiency, kidney failure, pancreatitis, calcium channel blocker overdose, rhabdomyolysis, tumor lysis syndrome, and medications such as bisphosphonates or denosumab. Diagnosis should generally be confirmed by determining the corrected calcium or ionized calcium level. Specific changes may also be seen on an electrocardiogram (ECG).

Back pain (Latin: dorsalgia) is pain felt in the back. It may be classified as neck pain (cervical), middle back pain (thoracic), lower back pain (lumbar) or coccydynia (tailbone or sacral pain) based on the segment affected. The lumbar area is the most common area affected. An episode of back pain may be acute, subacute or chronic depending on the duration. The pain may be characterized as a dull ache, shooting or piercing pain or a burning sensation. Discomfort can radiate to the arms and hands as well as the legs or feet, and may include numbness or weakness in the legs and arms.

The majority of back pain is nonspecific and idiopathic. Common underlying mechanisms include degenerative or traumatic changes to the discs and facet joints, which can then cause secondary pain in the muscles and nerves and referred pain to the bones, joints and extremities. Diseases and inflammation of the gallbladder, pancreas, aorta and kidneys may also cause referred pain in the back. Tumors of the vertebrae, neural tissues and adjacent structures can also manifest as back pain.

Radiculopathy (from Latin radix 'root'; from Ancient Greek πάθος (pathos) 'suffering'), also commonly referred to as pinched nerve, refers to a set of conditions in which one or more nerves are affected and do not work properly (a neuropathy). Radiculopathy can result in pain (radicular pain), weakness, altered sensation (paresthesia) or difficulty controlling specific muscles. Pinched nerves arise when surrounding bone or tissue, such as cartilage, muscles or tendons, put pressure on the nerve and disrupt its function.

In a radiculopathy, the problem occurs at or near the root of the nerve, shortly after its exit from the spinal cord. However, the pain or other symptoms often radiate to the part of the body served by that nerve. For example, a nerve root impingement in the neck can produce pain and weakness in the forearm. Likewise, an impingement in the lower back or lumbar-sacral spine can be manifested with symptoms in the foot.

A scorpion sting is an injury caused by the stinger of a scorpion resulting in the medical condition known as scorpionism, which may vary in severity. The anatomical part of the scorpion that delivers the sting is called a "telson". In typical cases, scorpion stings usually result in pain, paresthesia, and variable swelling. In serious cases, scorpion stings may involve the envenomation of humans by toxic scorpions, which may result in extreme pain, serious illness, or even death depending on the toxicity of the venom.

Most scorpion stings range in severity from minor swelling to medically significant lesions, with only a few able to cause severe allergic, neurotic or necrotic reactions. However, scorpion stings account for approximately 3,000 deaths a year worldwide. The Brazilian yellow scorpion (Tityus serrulatus) is one species known for being especially dangerous, being responsible for most scorpion sting fatalities in South America.