• Redness
• Swelling
• Heat
• Pain
• Loss of Function

1. What Is the Main Cause of Inflammation in the Body?

There are many causes of inflammation that is triggered by the body’s immune system:

• Injury such as a splinter, scrapes, trauma, or any damage caused by a foreign object.
• Pathogens, including viruses, bacteria, parasites, or fungi
• Chemicals such as glucose, fatty acids, chemical irritants (e.g., acids), toxins, and alcohol
• Radiation such as sunburns
• Biological such as damaged cells in the body

2. What Happens During Inflammation?

Inflammation involves the contribution of different immune cells which release substances known as inflammatory mediators, including hormones such as histamine and bradykinin [1].

These inflammatory mediators induce vasodilation (dilatation of the vessels) which promotes the blood flow in the injured tissue and the recruitment of inflammatory cells (neutrophils, monocytes, and endothelial cells) to the site of injury.

The vasodilatation and the blood rush into the injured tissue result in redness and heat which are 2 signs of acute inflammation.

The pain associated with inflammation is caused by the irritation of local nerves by the inflammatory mediators.

These inflammatory cells have specific roles during acute inflammation:

• Neutrophils initiate the phagocytosis and killing of pathogens to decontaminate the wound, while also promoting cell proliferation and angiogenesis.
• Monocytes also contribute to the phagocytosis and killing of pathogens, and become macrophages, which remove dead cells, and support cell proliferation and tissue restoration following injury.
• Endothelial cells are the building blocks for vessels, and during wound healing, these cells generate new vessels (angiogenesis) to satisfy the metabolic demands of the highly proliferative healing tissue. 

Depending on the site of injury, a transitory loss of function can be observed due to tissue damage, swelling, or pain during inflammation.

3. How long Does Inflammation Last For?

Inflammation can be acute lasting for a few days (2-3 days) or chronic which lasts for a longer time until the insult is resolved.

What Are the Outcomes of Inflammation?

The resolution of acute inflammation (initial inflammation) depends on the causes and the extent of tissue damage. It is characterized by the following outcomes:

• Complete repair of the injured tissue and without scars
• Resolution of the inflammation with the formation of a scar or fibrosis
• Formation of an abscess
• Chronic inflammation if the initial inflammation persists and remains unresolved

The complete repair of the injured tissue or the formation of scars is mediated by a process known as wound healing.

Wound healing is a natural reaction of our body to tissue damage and involves crosstalk between different cells, cytokines, inflammatory mediators, and the vascular system to repair the damaged tissue.

4. What Are the Most Common Inflammatory Diseases?

The most common inflammatory diseases are associated with chronic mediated inflammation which includes the following diseases [2]:

• Rheumatoid Arthritis
• Cardiovascular diseases
• Inflammatory Bowel Disease (IBD) 
• Allergic Asthma
• Chronic obstructive pulmonary disease (COPD)
• Diabetes
• Chronic Kidney Disease
• Cancer

4.1. Rheumatoid Arthritis

Rheumatoid arthritis is due to a local chronic inflammation that results in the infiltration of immune cells into the joints and the release of inflammatory mediators such as cytokines.

4.2. Cardiovascular diseases

Atherosclerosis is associated with a chronic inflammation that leads to heart diseases such as stroke, and myocardial infarction.

4.3. Inflammatory Bowel Disease (IBD)

Inflammatory Bowel Disease (IBD) is a group of chronic inflammatory disorders affecting the bowels that are caused by ulcerative colitis (inflammation of the colon due to ulcer) or Crohn’s disease.

4.4. Allergic Asthma

Allergic asthma is due to the inflammation of the airways caused by the inhalation of an allergen which results in their swelling and tightening affecting breathing.

4.5. Chronic obstructive pulmonary disease (COPD)

COPD is a chronic inflammatory lung disease due to the exposure of the airways to harmful particles or gases causing inflammation that obstruct airflow in the lung leading to breathing difficulties.

4.6. Diabetes

One of the characteristics of diabetes is the infiltration of immune cells, such as macrophages, into pancreatic tissue, and their release of pro-inflammatory molecules responsible for inflammation.

4.7. Chronic Kidney Disease (CDK)

Chronic kidney disease or chronic kidney failure is a progressive loss of the function of the kidney resulting from the accumulation of body wastes and fluids in the blood.

One of the causes of chronic kidney disease is the inflammation of the glomeruli that filter blood for the elimination of waste and fluids in urine.

4.8. Cancer

Chronic inflammation is one of the characteristics of different types of cancer from various origins (Prostate, hepatic, colorectal, ovarian, pancreatic, and lung cancers).

4.9. Neurodegenerative diseases

Neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease are associated with the production of proinflammatory molecules by the brain resident immune cells and microglia which cause brain damage.

5. What Is the Difference Between Inflammation and Infection?

Infections cause inflammation which is a natural process by which the body’s immune system fights against pathogens, including bacteria, viruses, fungi, or parasites.

6. How Do You Get Rid of Inflammation in the Body?

Unlike acute inflammation, chronic inflammation can last for a longer period, and therefore, requires management and treatment through lifestyle changes or medications [3].

6.1. Lifestyle changes

6.1.1. Diet

A diet rich in glucose and processed food rich in saturated fat and trans fats promotes inflammation leading to cardiovascular diseases and type 2 diabetes. Hence, a low glucose diet and avoiding processed food can prevent inflammation.

A diet rich in vegetables and fish oils, nuts, mung bean, green and black teas, and certain species (e.g., ginger, turmeric) can prevent or reduce inflammation as they contain antioxidants and polyphenols which have anti-inflammatory properties.

6.1.2. Physical Activity

In addition to weight loss associated with exercising, physical activity also results in energy consumption with reduces the levels of proinflammatory molecules in the body.

6.2. Medications

The most used anti-inflammatory medications include nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids. 

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as naproxen, ibuprofen, and aspirin, alleviate pain by inhibiting the function of the enzyme cyclooxygenase (Cox) involved in the synthesis of the proinflammatory molecules, prostaglandins.

Corticosteroids are prescribed for some inflammatory conditions such as arthritis, asthma, systemic lupus, and sarcoidosis.

Conclusion

Acute inflammation is a natural process by which the body’s immune system responds to injuries and infections. Acute inflammation takes a few days to resolve, leading to a complete repair of damaged tissues, fibrosis (scars), formation of an abscess, or chronic inflammation.

Chronic inflammation can be associated with several inflammatory diseases such as rheumatoid arthritis, allergic asthma, cancer, diabetes, cardiovascular diseases, chronic kidney disease, COPD, inflammatory bowel disease, and neurodegenerative diseases.

The treatment of chronic inflammation includes lifestyle changes, physical activity, and medications using anti-inflammatory drugs such as NSAIDs and corticosteroids.

The post What Are the 5 Classic Signs of Inflammation? appeared first on .

The hypothalamus works like a thermostat for the body and maintains the temperature in the range of 97.7-99.5 °F (36.5-37.5 °C) [1].

• What Is Hypothermia?

Hypothermia is when the body temperature is lower than 95 °F (35.5 °C).

• What Is Fever?

Hyperthermia is when the body temperature is higher than 99.5 °F (37.5 °C).

• What Is Hyperpyrexia?

Hyperpyrexia is when the temperature is higher than 104 °F (40 °C).

1. How Does the Hypothalamus Regulate Body Temperature?

The Hypothalamus regulates body temperature (Thermoregulation) through 3 mechanisms: Afferent sensing, central sensing, and efferent responses [2].

• Afferent Sensing

Afferent sensing is associated with temperature sensors known as thermoreceptors that are distributed throughout the body.

Thermoreceptors are sensory nerve endings that are part of the nervous system. They are categorized into receptors for warmth detection and receptors for cold detection [3].

Receptors for warmth detection are known as C fibers, while receptors for cold are known as Aδ fibers.

• Central Control

This part is controlled by the hypothalamus which receives information about the body temperature from the thermoreceptors.

• Efferent Responses

Efferent responses are automatic responses to changes in the temperature such as sweating, vasoconstriction (narrowing of the vessels), vasodilatation (dilatation of the vessels), and shivering [4].

2. What Hormone Controls Body Temperature?

The hypothalamus is the part of the brain that controls body temperature; however, heat is internally generated by the metabolisms (energy production) of the different organs of the body where thyroid hormones such as thyroxine (T4), and triiodothyronine (T3) play an essential role.

3. Does Low Body Temperature Indicate Thyroid Problems?

A low body temperature is not necessarily due to problems with the thyroid; however, increased sensitivity to cold is one of the symptoms of hypothyroidism [5].

4. What Time of Day Is Body Temperature the Highest?

The highest body temperature was reported to be an early evening at 6 pm [6].

5. What Factors Affect Body Temperature?

Temperature fluctuations can be associated with the following factors:

• Age

Older individuals (more than 60 years old) have a lower temperature mean (average) compared to those individuals less than 60 years old [1] [7].

• Sex

Women have a slightly lower temperature than men [1]. However, during pregnancy and ovulation, this temperature increases, while it is lower at the start of the menstrual cycle.

• Circadian Rhythms

The body temperature is highest at 6 pm in the evening and lowest at 3 am in the morning [6].

• Physical activity

During physical activity and exercise the body generates a significant amount of heat due to the intense energy consumption.

• Meals

There is an increase in the body s metabolism meals which leads to an increase in the temperature of the body.

• Fever

Fever is due to infections such as a virus or bacteria, heat exhaustion, and inflammation (e.g., rheumatoid arthritis).

• Medications

Antibiotics and blood pressure or seizures can increase the body temperature.

6. What Vitamins Help with Body Temperature?

Vitamins B1, B2, B3, B5, and B7 (Biotin) are directly involved in the metabolic conversion of food into energy necessary for the maintenance of body temperature.

7. Can Mental Stress Cause Fever?

Some individuals, especially young women, develop a high fever when they are exposed to emotional events which cause stress. This type of fever is known as psychogenic fever [8].

8. What Are the Disorders of Body Temperature?

Disorders of the body temperature include any disorders that can cause a fever or hypothermia.

8.1. What Causes Fever?

Fever is mainly caused by sepsis, however, inflammation, and medications can also contribute to fever.

8.1.1. What is Sepsis?

During sepsis, fever is caused by exogenous pyrogens (e.g., pathogens) or endogenous pyrogens such as cytokines that interact with an area of the brain known as the organum vasculosum of the lamina terminalis (OVLT) or supraoptic crest.

The activation of the OVLT results in the increase in the synthesis of molecules known as prostanoids which are involved in inflammation (e.g., prostaglandins and prostacyclins) and in vasoconstriction (thromboxanes).

Prostanoids act by slowing down the activity of the warm sensitive neurons of the hypothalamus leading to an increase in the temperature [9].

8.1.2. Is Fever Associated with Inflammation?

Inflammation is a natural event that occurs following tissue damage or infections that results in swelling, redness, heat, and pain.

During inflammation, several inflammatory mediators are released by the cells involved in wound healing or in fighting infections.

These mediators are also pyrogenic (causing fever) and may act in a similar way to that of the sepsis pyrogenic mediators.

In some cancer patients fever also appears to be mediated by the same mechanism as that of sepsis [10].

8.1.3. Which Drugs Induce fever?

Some pharmacological drugs can cause heat loss from the peripheries, directly damage tissues, interfere with the hypothalamus central temperature regulation, stimulate an immune response, or have pyrogenic properties [9].

• Antimicrobial agents such as beta-lactam antibodies and sulphonamides.
• Volatile anesthesic agents
• Anti-depressants such as SSRI
• Opioids such as fentanyl
• Central nervous system stimulants such as amphetamines and cocaine
• Psychedelics such as lysergide
• Anticholinergic agents such as bronchodilators and ephedrine
• Anti-emetics such as cyclizine
• Synthetic cathinones such as bupropion

8.1.4. What Is Endocrine fever?

Hyperthyroidism is associated with the increase in body temperature due to the increase in the secretion of the thyroid hormones, thyroxine (T4), and triiodothyronine (T3) that play an essential role in the metabolisms (energy production) of the different organs of the body [10].

8.2. What Causes Hypothermia?

There are several disorders and medications that cause hypothermia:

8.2.1. What Disorders Cause Hypothermia?

Some disorders can affect the body capacity to regulate core temperature:

• Hypothyroidism
• Diabetes
• Anorexia Nervosa
• Poor Nutrition
• Spinal Cord Injuries
• Severe Arthritis
• Stroke
• Parkinson Disease

8.2.2. What Medications Cause Hypothermia?

Changes in body temperature can be caused by the following drugs:

• Sedatives
• Antipsychotics
• Narcotic Pain Medications
• Antidepressants

8.3. Heart-Related Illness

In chronic heart failure, there is an alteration in the balance between heat production and heat loss but also an increased risk of ischemia or stroke that can damage the brain and also affect the metabolism [11].

Conclusion

The body temperature is controlled by the hypothalamus through mechanisms that involve afferent sensing, central control, and efferent responses. Any factors that disturb the normal functioning of these mechanisms lead to a change in the body’s temperature.

The post What Controls Body Temperature? appeared first on .

• Direct Sciatic Nerve Compression
• Inflammation

It is estimated that the annual incidence in the general population is between 1% to 5% and the lifetime incidence is between 10% and 40% [1].

1- How Long Will Sciatica Take to Heal?

Sciatica can lasts 4-6 weeks, however, it can last longer depending on the causes.

2- What is the Sciatic Nerve?

The sciatic nerve is responsible for sensations in the feet and legs.

It is hosted and protected by the spine and starts at the base of the brain and travels all the way to the lumbar region of the spine where it branches into right and left.

Each branch will continue its enervation route all the way to the feet (right or left).

2- What Triggers Sciatica?

• Direct Sciatic Nerve Compression

Our spine or vertebral column is made of 24 vertebrates, the sacrum, and the coccyx.

We have 7 vertebrates of the neck (cervical vertebrates), 12 of the midback (thoracic vertebrates), and 5 of the lower back (lumbar vertebrates).

Each vertebrate is joined to another vertebrate by a disc (intervertebral disk).

• Lumbar Herniated Disc

When a lumbar intervertebral disc bulges or herniates, it can compress the sciatic nerve resulting in pain.

Lumbar Herniated Disc causes 90% of the direct sciatic nerve compressions [2].

• Degeneration

The degeneration of the tissues of vertebrates in the lumbar part of the spine can result in the compression of the sciatic nerve.

• Spondylolisthesis

When a vertebrate slips out of position due to a stress fracture it can compress the sciatic nerve.

• Lumbar Spinal Stenosis

The spine canal through with passes the sciatic nerve may decrease in size due to factors, such as age, resulting in the compression of the sciatic nerve.

• Lumbar or Pelvic Muscular Spasm

Spasm in muscles such as the piriformis muscle can irritate or compress the sciatic nerve.

• Hematoma or abscess

Hematoma or abscesses around the sciatic nerve can cause compression of the sciatic nerve.

• Tumors

Spinal tumors that originate from the vertebra, spinal cord, or nerves can also compress the sciatic nerve.

• Inflammation

Within the spine, there is an acid substance known as hyaluronic acid. When the spine is damaged, this substance leaks into the surrounding tissues of the sciatic nerve causing its irritation, inflammation, or compression.

3- What Are the Risk Factors of Sciatic Nerve Pain (Sciatica)?

• Occupation and Sciatica

There is a predisposition for sciatica in workers including truck drivers, carpenters, and machine operators due to long hours in uncomfortable positions.

• Lack of Physical Activity and Sciatica

Lack of physical activity can weaken lower back muscles (lack of flexibility, tone, and movement) resulting in less support for the lumbar spine and potential compression of the sciatic nerve.

• Smoking and Sciatica

Although the mechanism is not well known, smoking appears to be a modest risk of sciatica [3].

• Mental Health and Sciatic

Depression and anxiety disorders have been associated with sciatica due to the release of inflammation factors (inflammatory mediators) in the lower back region which can irritate the sciatic nerve [4].

• Tall height in older age groups (50 to 60 years)

A study that included 13680 participants found a correlation between tall height and lower back pain or related surgery [5].

• Obesity and excess weight

Weight being carried in the front can be a weight on the spine and related muscles which may cause muscle strain that can potentially lead to sciatica.

• Genetic susceptibility

A study reported a higher incidence of sciatica or prolapsed disc in first-degree relatives of patients hospitalized for herniated lumbar disc or surgery [6].  

Another study of 9365 pairs of adult twins found a correlation between genetics and the incidence of sciatica [7].

• Previous injury

Previous injuries in athletes or workers can result in lumbar intervertebral disc bulges or herniation.

• Diabetes

Diabetes is a metabolic disorder that can cause damages to the sciatic nerve.

• Pregnancy

The growing baby during pregnancy can generate extra weight resulting in a weight that is applied on the spine and related muscles which may cause muscle strain.

• Recreational Activities

In a study that involved 2077 workers, regular walking and jogging have been shown to increase the incidence of sciatica [8].

5- What Are the Symptoms of Sciatica?

• Pain in the lower back, buttock, and leg which can be intermittent or persistent.
• Reduced movement and mobility together with moderate or severe pain.
• Weakness in the lower back and leg.
• Numbness or pins-and-needles sensations along the leg and foot.

6- When Should I Worry About Sciatica?

Sciatica can be due to severe or chronic conditions such as tumors, bilateral sciatica, scarred tissues, hematoma, cysts or abscesses, spinal tuberculosis, medications non-responsive infections, or fracture in the vertebrates of the lumbar spine.

These conditions may require surgery to restore the function of the lower spine and surrounding tissues.

5- Sciatica Treatment

Sciatica treatment may involve non-surgical or surgical therapies.

• Non-surgical therapies

Exercises for Sciatica

Physical therapy aims at restoring strength to the spine and lower-back muscles, buttocks, hip, and abdomen which may involve swimming, walking, and specific stretching movements with a help of a physical therapist.

Lifestyle Changes

Losing weight through a healthy diet can significantly reduce chronic sciatica by decreasing the weight being carried in the front, and therefore, reducing the weight on the spine and related muscles.

This effort can be complemented with exercise to strengthen the spine and lower back muscles, buttocks, hip, and abdomen.

For workers with a predisposition for sciatica, preventing certain positions or intermittent stretching while working can prevent or reduce the risk of sciatica.

Alternative therapies

Acupuncture, yoga, and massages can relieve muscle spasms at the lower back and leg, and therefore, pain associated with sciatica.

Medication

Non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen, and spinal injections of steroids (corticosteroids) are used to temporarily reduce pain associated with inflammation and swelling.

Myorelaxants are also used to relax the muscles and relieve the spasms.

• Surgery

Surgery is required to remove the tumors, abscesses, hematomas that compress the spine and the sciatic nerve.

When the sciatica is due to a hernia of a disc or multiple discs or to lumbar spinal stenosis, surgery is necessary to restore their function.

Conclusion

Sciatica is a very painful experience that can be due to lifestyle or working conditions but also to severely debilitating conditions that require several surgical procedures to restore the function of the lower spine and reduce the irritation or compression of the sciatic nerve.

The post What Causes Sciatic Nerve Pain? appeared first on .