General Pathology 101: Inflammatory Diseases

Foreword

Inflammation is a vital response mechanism to threats, and it is part of a beneficial defense system that has evolved and been conserved evolutionarily over thousands of years. But why is this process associated with diseases? While inflammation is primarily protective and helps maintain tissue balance, uncontrolled inflammation can become detrimental, leading to the progression of chronic inflammatory diseases. This 101 series aims to provide a comprehensive understanding of the inflammatory process by emphasizing its historical context, intricate mechanisms, and events that will determine its end or the development of diseases. Through six captivating chapters, readers will obtain a holistic perspective on inflammation and its significance in health and disease.

This 101 series is divided into six articles including:

1. General Pathology 101: Inflammation - Historical Perspectives

2. General Pathology 101: Inflammatory Cells and Mediators

3. General Pathology 101: Inflammatory Cells Recruitment and Clearance

4. General Pathology 101: Resolution of Inflammation

5. General Pathology 101: Acute vs. Chronic Inflammation

6. General Pathology 101: Inflammatory Diseases

General Pathology 101: Inflammatory Diseases

Inflammation is a common condition in many diseases and it is an essential response of the body that enables the survival and maintenance of tissue in a healthy state. In some cases, inflammation progresses and threat becoming detrimental, by leading thought to the development of acute or chronic diseases. Inflammatory conditions can affect different organs and systems in the body. Over the last few decades, the scientific and medical communities have been working diligently to unravel the mechanisms underlying different types of inflammatory disorders, in order to ensure effective treatment through the development of anti-inflammatory and pro-resolving therapies. This article aims to provide a descriptive overview of several inflammatory diseases, which for ease of reading have been divided into the following categories: cardiovascular, respiratory, central nervous system, musculoskeletal and gastrointestinal.

Cardiovascular Inflammatory Diseases

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide (Roth et al., 2020). Many of these conditions are inflammatory in nature, which can affect blood vessels and the heart, resulting in various complications and clinical manifestations. Some examples of inflammatory cardiovascular diseases will be discussed below.

Endocarditis, Myocarditis, Pericarditis: The heart is made up of three main layers: the endocardium, the innermost layer, which lines the chambers and valves, facilitates blood flow, and prevents blood clot formation; the myocardium, the middle and thickest layer, which is made up of cardiac muscle tissue and is responsible for the contraction of the heart; and the epicardium, the outermost layer of the heart, which protects it and secretes a lubricating fluid that reduces friction during heartbeats. The epicardium is part of the pericardium, a double-walled sac that covers the cardiac muscle. Endocarditis, Myocarditis, and Pericarditis are characterized by inflammation of the endocardium, myocardium, and pericardium tissues, respectively (Lu et al., 2015). These conditions can be caused by bacterial, fungal, or viral infections, autoimmune diseases; or exposure to toxins. Damage to the heart valves (e.g., in endocarditis) and other serious complications such as weakening of the heart muscle are common features. Symptoms of heart inflammation within the three layers include chest pain, fatigue, and shortness of breath (Lu et al., 2015).

Figure 1: Inflammation of the heart layers (Cleveland Clinic, 2021).

Rheumatic heart disease: Rheumatic heart disease is a complication of rheumatic fever, an inflammatory condition caused by streptococcal infections. The body's immune system responds to the streptococcal infection by attacking its own tissues, particularly the heart valves. The damage to the heart valves is permanent and leads to rheumatic heart disease, which is associated with valve dysfunction and heart failure (Carapetis et al., 2016).

Atherosclerosis: This condition involves the inflammation of the arterial walls due to the formation of plaque, composed of cholesterol, calcium, inflammatory cells (mainly macrophages), and other compounds. Atherosclerosis can lead to arterial narrowing and restrict blood flow, potentially leading to heart attacks and strokes (Libby et al., 2019).

Figure 2: Stages of atherosclerosis (Mayo Clinic, 2022).

These are several examples of inflammatory cardiovascular diseases, where different tissues and organs used to be affected. Each condition show its own causes, symptoms, and complications. Measures such as prevention, early diagnosis and appropriate treatment are essential in managing these conditions and avoiding serious complications.

Respiratory Inflammatory Diseases

Respiratory inflammatory diseases involve inflammation of the respiratory tract, including the upper airways, such as the nasal cavities, pharynx and larynx, and the lower airways, such as the trachea, lungs, bronchi, bronchioles and alveoli. Inflammation of the lower tract is more harmful and can lead to permanent damage to the lungs, compromising the patient's quality of life. Respiratory inflammation can be caused by microbial infections (viruses, fungi, and bacteria), autoimmune conditions, or toxic agents (air pollution, cigarette smoke) (Aghasafari et al., 2019).

Figure 3: Upper and lower airways of the respiratory system (Basicmedical Key, 2017).

Acute Respiratory Distress Syndrome (ARDS): ARDS is a severe lung condition characterized by widespread inflammation and fluid accumulation in the lungs, leading to respiratory failure. It can occur in response to severe infections, trauma, aspiration of gastric contents, or other causes, and is often seen in critically ill patients (Matthay et al., 2019).

Asthma: Asthma is a chronic inflammatory condition characterized by bronchial inflammation, airway narrowing, and increased mucus production. Common symptoms include wheezing, coughing, chest tightness, and shortness of breath. Asthma is often episodic, with a variety of triggers that can vary from person to person. Triggers for asthma attacks can include different types of allergens, pollutants, respiratory infections, exercise, and temperature changes (Mims, 2015).

Chronic Obstructive Pulmonary Disease (COPD): COPD is a group of progressive diseases that restrict airflow and destroy tissue in the lungs, including chronic bronchitis and emphysema, affecting 300 million people worldwide (Ruvuna & Sood, 2020). COPD is characterized by airflow blockage and breathing problems. Chronic inflammation in the airways and lung tissue contributes to the development and progression of COPD, which develops very slowly over time and is often due to long-term exposure to irritants such as cigarette smoke or air pollution. Other causes can be ascribed to secondhand smoke, environmental and occupational exposures, and alpha-1 antitrypsin deficiency, a genetic disorder that predisposes individuals to early-onset emphysema (Leap et al., 2021). COPD is marked by the persistent recruitment of inflammatory cells (e.g., macrophages, neutrophils) into the lungs and the production and release of inflammatory mediators, including protases, specialized molecules responsible for breaking down proteins into smaller parts, inducing tissue destruction and damage to the alveolar air sacs (alveoli), the gas-exchanging surfaces of the lungs. (Leap et al., 2021).

Figure 4: Characteristics, symptoms and causes of COPD (Medicover Hospitals, n.d.).

Bronchitis: Bronchitis is the specific term that identifies with the inflammation of the bronchial tubes. It is commonly divided into acute and chronic. Acute bronchitis is usually caused by viral infections and usually resolves within a few weeks. Chronic bronchitis, the most common form of COPD, involves long-term inflammation of the bronchial tubes, the main symptoms of which include persistent sputum-producing cough, mucus production, wheezing, and low-grade fever (Woodfork K., 2008).

Pneumonia: Pneumonia is a common respiratory infection of the lungs caused by bacteria, viruses, or fungi. This condition can affect individuals of all ages worldwide, but is most common in susceptible individuals, including children under 5 years of age and older adults with pre-existing chronic diseases (Torres et al., 2021). Pneumonia is broadly classified as community-acquired pneumonia (acquired outside of a hospital) or hospital-acquired pneumonia (acquired 48 hours or more after hospital admission). Inflammatory responses triggered by the infection lead to symptoms such as fever, cough, difficulty breathing, chest pain, sputum production and fatigue (Torres et al., 2021).

Interstitial Lung Diseases (ILDs): ILDs are a group of disorders characterized by inflammation and scarring (fibrosis) of the interstitium, a tissue that surrounds the air sacs in the lungs. Causes may be due to environmental exposure to toxic dust or gases and certain medications, autoimmune (e.g., rheumatoid arthritis, scleroderma), or idiopathic (cause is unknown). These conditions can lead to progressive difficulty breathing due to impaired gas exchange, resulting in shortness of breath, reduced exercise tolerance, and decreased quality of life (Wijsenbeek et al., 2022).

Many of these conditions cause damage to lung tissue that is irreversible, affecting the patient's breathing and overall quality of life. As shown, each condition has its own roots, risk factors, symptoms, and treatment approaches, but for some conditions, lifestyle changes such as avoiding exposure to pollutants and toxic agents can be essential in prevention. Early diagnosis and treatment are crucial to preventing complications and improving outcomes for individuals with these conditions.

Central Nervous System Inflammatory Diseases

Inflammatory diseases of the central nervous system (CNS) involve inflammation of the brain, spinal cord, and surrounding tissues. It can lead to serious complications, including brain damage, coma, and even death. Therefore, prompt medical attention is crucial for proper diagnosis and treatment. Some examples of central nervous system diseases associated with inflammation will be discussed below.

Meningitis: The brain and spinal cord are protected by three layers of membranes known as meninges (the dura mater, arachnoid mater, and pia mater). Meningitis is an inflammation of these layers caused by infectious pathogens—primarily bacteria and virus— or non-infectious processes (e.g., autoimmune disorders, cancer). Diagnosis involves clinical assessment and laboratory tests—analysis of blood or cerebrospinal fluid (the fluid that surrounds the brain and spinal cord). Symptoms of meningitis include headache, fever, stiff neck, sensitivity to light, confusion, and in severe cases, seizures and coma (Richie, 2022; van de Beek et al., 2016).

Figure 5: Inflammation of the meninges (Headway, n.d.).

Encephalitis: Encephalitis is an inflammation of the brain, often caused either by an infectious agent (virus, bacteria, fungi, or parasites) or by an autoimmune process. Bacterial, fungal, and parasitic infections are less prevalent, while viruses such as herpesviruses, arboviruses, enteroviruses, and adenoviruses are the most common causes of infectious encephalitis globally. Inflammatory responses in the brain can lead to symptoms such as fever, headaches, confusion, behavioral changes, movement disorders, seizures, and neurological deficits (Alam et al., 2023; Richie, 2022).

Acute Disseminated Encephalomyelitis (ADEM): ADEM is a rare autoimmune condition characterized by inflammation of the brain, spinal cord, and occasionally the optic nerve, often occurring following viral infections or immunization (vaccinations). Symptoms typically include fever, headache, confusion, seizures, and neurological deficits. ADEM is particularly common in children, but is usually transient and self-limiting (Paolilo et al., 2020).

Multiple Sclerosis (MS): MS is a chronic inflammatory neurodegenerative disease associated with neuronal cell disfunction and death, accompanied by degradation of the protective myelin sheath that covers nerve fibers in the brain and spinal cord. This results in a wide range of symptoms, such as fatigue, weakness, numbness, coordination problems, cognitive impairment and, ultimately, severe physical or cognitive disability. The exact cause of MS is still unknown. However, it is generally accepted that a combination of genetic predisposition and environmental factors contribute significantly to the development and progression of the disease (Ghasemi et al., 2017).

Figure 6: Multiple sclerosis affects different organs and tissues (UFHeatlh, 2023).

Central nervous system disorders are critical and can cause permanent brain damage or even death. Early diagnosis and appropriate treatment are essential to prevent complications and improve outcomes for individuals affected by these conditions.

Musculoskeletal System Inflammatory Diseases

Inflammation of the musculoskeletal system involves any disorder of the muscles, bones, joints, and related tissues. The musculoskeletal system is also known as the locomotor system. Dysfunctions in this system can lead to incapacitation and limitations in locomotion, in addition to chronic pain. In some diseases, inflammation of these structures, especially the joints, can lead to irreversible degenerative conditions. Some examples of musculoskeletal diseases where inflammation plays a crucial role in their development and progress, will be discussed below:

Rheumatoid Arthritis (RA): RA is a chronic autoimmune disease characterized by inflammation of the synovium, a membrane lining of the joints that is responsible for providing nutrients to the cartilage and lubricants that enable the cartilage surfaces to operate in a low-friction environment (Smolen et al., 2018). Inflammation of the synovium can cause cartilage and bone damage, leading to joint pain, swelling, stiffness, and progressive injury. Risk factors involve genetics, female gender, and environmental factors, the latter including smoking, infectious organisms, vitamin D deficiency, obesity, and others (Smolen et al., 2018). RA can affect multiple joints symmetrically and most commonly affects the hands, wrists, elbows, shoulders, knees, ankles, and feet, but can also affect other organs such as the skin, blood vessels, lungs, kidneys, and heart (Smolen et al., 2018).

Figure 7: Clinical manifestations of rheumatoid arthritis (Smolen et al., 2018).

Osteoarthritis (OA): OA is the most common form of arthritis, affecting millions of people worldwide. OA has primarily been classified as a degenerative joint disease, but recent studies have shown that OA also involves inflammation of the joint tissues. Over time, the cartilage that cushions the ends of the bones wears down, leading to pain, stiffness, and reduced joint mobility. Inflammation of the synovium (synovitis) and the formation of bony protuberances or spurs are often observed (Hunter & Bierma-Zeinstra, 2019). OA can be divided into 2 categories: primary osteoarthritis, which is mostly related to aging, and secondary osteoarthritis, which is caused by another disease or condition including trauma, obesity, and RA (Hsu & Siwiec, 2024). OA commonly affects weight-bearing joints such as the hips, spine, and knees, the latter being the most commonly affected, followed by the hand joints. OA is a leading cause of disability in older adults and is considered one of the leading causes of disabling chronic pain in patients (Hunter & Bierma-Zeinstra, 2019).

Ankylosing Spondylitis (AS): AS is a type of chronic inflammatory autoimmune disease that primarily affects the spine, causing inflammation of the spinal joints, tendons, and ligaments. In advanced cases, fibrosis and calcification of tissues is frequent, resulting in the loss of flexibility and the fusion of the spine. AS is accompanied by chronic pain and stiffness in the back and pelvis and reduced spinal flexibility (Zhu et al., 2019).

Figure 8: Changes in posture and fusion of the spine in ankylosing spondylitis (Mayo Clinic, 2023).

Inflammatory Myopathies: Inflammatory myopathies are a group of rare autoimmune diseases that affect the muscles. These conditions are characterized by muscle weakness, pain, and sometimes reduced muscle mass but other organs can be affected, including the skin, joints, lungs, heart, and gastrointestinal tract (Lundberg et al., 2021). There are three major diseases: Dermatomyositis (DM), Polymyositis (PM), and Inclusion Body Myositis (IBM). DM is a type of inflammatory myopathy that involves both muscle and skin inflammation. The rash typically appears on the face, eyelids, knuckles, elbows, knees, chest, and back. In PM, muscle weakness occurs primarily in the muscles closest to the trunk of the body, such as the hips, thighs, shoulders, upper arms, and neck. IBM is the most common acquired myopathy after age 50, often affects men, and typically begins in the muscles of the fingers, wrists, and knees and later affects other muscles, including those of the legs, feet, and forearms (Atluri, 2016).

Osteomyelitis: Osteomyelitis is an infection-related inflammatory disease of the bone. This condition can be acute or chronic and usually, the infection starts in another part of the body and spreads to the bone through the bloodstream. Treatment is notoriously difficult due to the nature of bone and requires long courses of antibiotics. Early diagnosis is essential for effective treatment (Lew & Waldvogel, 2004).

Gout: Gout is a type of arthritis characterized by the deposition of monosodium urate crystals (uric acid) in the joints, leading to inflammation and tissue damage, typically affecting the big toe. Gout results from an imbalance in uric acid metabolism, leading to increased levels in the blood and crystal formation and deposition in the joints. Sudden and severe attacks of pain, swelling, redness, and warmth in the toe are the most common symptoms (Dalbeth et al., 2019).

Figure 9: Typical clinical and imaging features of gout (Dalbeth et al., 2019).

These are just a few examples of inflammatory diseases of the musculoskeletal system, each with its own unique characteristics, but all with one thing in common: they affect patients' mobility and quality of life. Treatment depends on the specific condition and may include different types of medications, physical therapy, exercise, lifestyle changes and, in some cases, surgery. Early diagnosis and appropriate treatment are crucial for reducing tissue damage, controlling inflammation, relieving symptoms —particularly pain—, and preventing long-term complications in affected individuals.

Gastrointestinal Inflammatory Diseases

Gastrointestinal inflammatory diseases involve inflammation of the digestive tract and related organs. Inflammation in these organs and tissues can impair the absorption of nutrients, leading to malnutrition, weight loss, and deficiencies of essential vitamins and minerals. Abscesses and chronic pain are also common. Some examples of inflammatory diseases of the gastrointestinal tract include:

Esophagitis, Gastritis, and Diverticulitis: These conditions are characterized by inflammation of the esophagus, stomach, or large intestine (colon), respectively. Esophagitis often develops due to irritation from gastric acid reflux, or due to certain conditions such as infections or the use of certain types of medications. Symptoms may include difficulty or pain when swallowing (dysphagia and odynophagia, respectively), chest pain, and regurgitation (Grossi et al., 2017). Gastritis is a prevalent medical condition that can be acute or chronic and involves inflammation of the stomach lining. It can result from infection (e.g., Helicobacter pylori bacteria), long-term use of medications (e.g., nonsteroidal anti-inflammatory drugs NSAIDs), use of mucosal irritants (e.g., alcohol), stress, and others. Symptoms may include abdominal pain, nausea, vomiting, bloating, and loss of appetite. Severe complications include autoimmune gastritis and cancer (Azer et al., 2023). While the causes of gastritis and esophagitis are better established, the development of diverticulitis is not. Diverticulitis is thought to result from the complex interaction of diet, lifestyle, medications, genetics, and gut microbiome factors, resulting in defects in the mucosal barrier leading to inflammation in the colon. It can lead to symptoms such as abdominal pain (usually in the lower left side), fever, nausea, vomiting, and changes in bowel habits. Complications of diverticulitis include abscess, peritonitis, perforation, and obstruction, which can eventually lead to intra-abdominal sepsis—associated with high morbidity and mortality (Strate & Morris, 2019).

Crohn's Disease: Crohn's disease is a chronic inflammatory bowel disease (IBD) that can affect the entire digestive tract, from the mouth to the anus. Inflammation can extend through the entire thickness of the intestinal wall, and the disease has periods of remission and flares. The patient can experience abdominal pain, diarrhea, nausea, vomiting, fatigue, weight loss, and malnutrition. The main risk factors for the development of Crohn's disease can be genetic and environmental, involving disruption of the intestinal mucosa and changes in the gut microbiota (Feuerstein & Cheifetz, 2017). 

Figure 10: Varieties of inflammatory bowel diseases (Johns Hopkins Medicine, n.d.).

Ulcerative Colitis (UC): UC is another type of IBD that affects the lower section of the gastrointestinal tract, including the colon and rectum (Figure 10). This condition is characterized by persistent inflammation and ulceration in the inner layer of the mucosa that absorbs water and some nutrients. Symptoms of UC include bloody diarrhea, abdominal pain, fecal urgency, and tenesmus (frequent need to defecate even when the rectum is empty). Disruption of the intestinal mucosa barriers and alterations of the intestinal microbiota are the main risk factors for developing UC (Feuerstein et al., 2019). Some individuals with IBD (Crohn's disease or UC) may also experience inflammation in the joints, leading to arthritis. This can cause symptoms such as joint pain, stiffness, swelling, and reduced mobility (Orchard, 2012).

Indeterminate Colitis (IC): Crohn's disease and ulcerative colitis sometimes mimic each other (some patients may exhibit features of both) and are not easily distinguished by using the standard diagnostic criteria for either condition precisely. In such cases, patients may be diagnosed with indeterminate colitis (IC), sometimes referred to as inflammatory bowel disease unclassified (IBDU), terms used to describe inflammatory bowel disease that does not fit into either Crohn's disease or ulcerative colitis (Venkateswaran et al., 2021).

Gastrointestinal inflammatory diseases can be caused by infections, autoimmune conditions, and lifestyle. Symptoms may vary depending on the affected organ. Treatment approaches include different types of medications (depending on the condition), dietary changes, and lifestyle modifications. Proper diagnosis and treatment are essential to control inflammation, relieve symptoms, and prevent further complications.

Systemic Inflammatory Diseases

Systemic inflammatory diseases affect the entire body rather than specific organs or systems. They often involve inflammation in multiple organs and tissues and can have widespread effects leading to organ damage. Some of the aforementioned diseases, such as rheumatoid arthritis and inflammatory bowel disease, can have systemic effects that cause tissue damage and lead to numerous clinical manifestations, including fatigue, pain, weight loss, and others (Levine & Burakoff, 2011; Wu et al., 2022).

Sepsis: This condition is characterized as a life-threatening syndrome that leads to multiple organ dysfunction (organ failure). Sepsis is a severe body response to infection that leads to a systemic inflammatory response. The symptoms of sepsis are highly variable and may include lethargy, low blood pressure, shortness of breath, and confusion, which are directly related to damage to the respiratory, cardiovascular, and central nervous systems. It is considered a serious disease that progresses very rapidly and has a high mortality rate (Jarczak et al., 2021).

Systemic Lupus Erythematosus (SLE): SLE is a complex chronic autoimmune disease associated with significant morbidity and mortality. In this condition, the body's immune system attacks its own tissues, leading to inflammation and damage to various organs including the joints, kidneys (lupus nephritis), heart, lungs, brain, and skin. Symptoms can vary widely but may include joint pain, fatigue, fever, Raynaud's phenomenon (blood stops flowing properly to the fingers and toes due to cold temperatures or stress), and skin rashes—the latter known as malar or butterfly rash, a typical sign that appears on the face over the bridge of the nose and cheeks (Shaikh et al., 2017).

Figure 11: Manifestations of systemic lupus erythematosus (Medline Plus, n.d.).

Systemic Sclerosis (Scleroderma): Systemic sclerosis is a chronic autoimmune disease characterized by excessive collagen production, leading to thickening and hardening of the skin and internal organs. It can affect the skin, blood vessels, digestive tract, lungs, kidneys, and heart, causing symptoms such as skin tightening, Raynaud's phenomenon, difficulty swallowing, and lung or heart complications (Denton & Khanna, 2017).

Vasculitis: Vasculitis refers to a group of disorders characterized by inflammation of the blood vessels, leading to narrowing, weakening, and sometimes blockage of the vessels. Symptoms can vary widely, depending on the location and type of lesion, and may include fever, fatigue, muscle and joint pain, rashes, nerve damage, and organ dysfunction (Langford, 2010).

Kawasaki disease: Kawasaki disease is a rare systemic disease characterized by inflammation of the blood vessels (medium-sized muscular arteries) throughout the body, being classified as a systemic vasculitis syndrome. It primarily affects infants and children under the age of 5 and can lead to inflammation of the coronary arteries (which supply blood to the heart), potentially resulting in coronary artery aneurysms and other cardiovascular complications if left untreated. Major symptoms include prolonged high fever lasting at least five days; conjunctivitis; skin rash; changes in the lips and oral cavity, including red, swollen, and chapped lips and strawberry tongue: red, swollen tongue with a white coating; swollen and red palms and soles; swollen lymph nodes in the neck (Takahashi et al., 2010).

Figure 12: Kawasaki disease symptoms (Kawasaki Kids Foundation, n.d.).

Systemic inflammatory diseases are complex conditions. Diagnosis often requires a thorough medical history, physical examination, and several types of tests, including laboratory tests (blood, urine, tissue, and others), imaging tests (ultrasound, X-Ray, magnetic resonance imaging, computed tomography, and others), or additional specialized tests, depending on the condition and when needed. Treatment typically involves a multidisciplinary approach and may include medications to suppress inflammation, manage symptoms, and prevent tissue damage and organ disfunction.

Treatment of Inflammatory Diseases

Managing inflammatory diseases involves a precise diagnosis and subsequent administration of medications (anti-inflammatory drugs, antibiotics, immunosuppressants, and others), with anti-inflammatory drugs being the primary choice for many conditions. Various types of anti-inflammatory drugs are available on the market, typically categorized as either non-steroidal anti-inflammatory drugs (NSAIDs) or glucocorticoids, the latter also referred to as steroidal anti-inflammatory drugs or corticosteroids (Sinniah et al., 2021). It's important to note that the majority of these medications require a doctor's prescription for safe use.

NSAIDs act by blocking enzymes called cyclooxygenases (COX-1 and COX-2), which are enzymes involved in the production of prostaglandins, essential molecules for the inflammatory process that induces fever and pain. The majority of NSAIDs are nonselective, which means that these drugs inhibit both COX-1 and COX-2 enzymes (Rainsford, 2007). Examples of nonselective NSAIDs include aspirin, ibuprofen, and naproxen. While COX-2 inhibition primarily controls inflammation, the inhibition of COX-1 has been associated with NSAIDs side effects in the gastrointestinal tract, such as indigestion, stomach aches, and bleeding. For this reason, selective COX-2 inhibitors have been developed (e.g., Celecoxib). However, these medications should be used with caution, as they may increase the risk of cardiovascular complications, including heart attack and stroke, in some patients (Rainsford, 2007). NSAIDs are used to treat mild to moderate pain and swelling and to relieve symptoms of arthritis (e.g., osteoarthritis, rheumatoid arthritis); conditions such as trauma, sports injuries, and fractures; and postoperative, headache, menstrual pain, and others (Sinniah et al., 2021).

Glucocorticoids (GCs) are a class of anti-inflammatory drugs that mimic the effects of hormones produced by the adrenal glands, particularly cortisol (Adcock & Mumby, 2017). These hormones play an essential role in the regulation of various physiological processes, including metabolism, immune response, and stress. GCs display potent anti-inflammatory effects and immunosuppressive properties (when the immune system is suppressed), making them essential in the treatment of various inflammatory and/or autoimmune conditions, including asthma, COPD, rheumatoid arthritis, IBDs, multiple sclerosis, SLE, sepsis, and others (Adcock & Mumby, 2017). Because of their potential side effects, GCs are typically prescribed at the lowest effective dose for the shortest duration necessary to achieve the desired therapeutic outcome. Adverse side effects include weight gain, fluid retention, high blood pressure, osteoporosis, diabetes, increased susceptibility to infections, reduced wound healing, mood changes, and skin and muscle atrophy (Adcock & Mumby, 2017). Patients using GCs must be closely monitored by healthcare providers to assess their response to treatment and manage any potential side effects.

Conclusion

Inflammatory diseases are very common and affect millions of people of all ages around the world. These conditions may affect different types of tissues and organs, exhibiting local or systemic effects. Inflammatory diseases are associated with tissue damage (irreversible in certain conditions and depending on the tissue) and chronic pain, which can contribute to the exacerbation of symptoms and the severity of the disease. Treatment of inflammatory diseases may primarily involve the administration of anti-inflammatory drugs. Adjunctive therapies may also be necessary, such as the administration of other medications, including antibiotics and immunosuppressants, dietary and lifestyle changes, physical therapy, and surgery.

Specialist monitoring of the use of anti-inflammatory drugs is essential to ensure effective, safe therapy and a better quality of life for patients. Currently, research and medical groups are committed to improve the therapeutic approach of anti-inflammatory drugs to reduce the associated adverse effects and develop more effective therapies. Further studies are needed to deepen our understanding of the mechanisms of action of anti-inflammatory drugs and the development and progression of inflammatory diseases. 

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