Giant Cell Arteritis

Overview

Epidemiology

• Most common idiopathic Idiopathic Dermatomyositis systemic vasculitis Vasculitis Inflammation of any one of the blood vessels, including the arteries; veins; and rest of the vasculature system in the body. Systemic Lupus Erythematosus
• Age is the greatest risk factor:
  • Generally affects individuals older than 50 years
  • Increased incidence Incidence The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time. Measures of Disease Frequency in the 8th and 9th decades of life
• 3 times more common in women
• Northern European and Scandinavian ancestry
• Lower body mass index Body mass index An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity ( BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity) is associated with a higher risk.

Etiology

• Exact cause is unknown.
• Genetic factors may increase susceptibility:
  • Genetic variants in the major histocompatibility complex Major histocompatibility complex The genetic region which contains the loci of genes which determine the structure of the serologically defined (sd) and lymphocyte-defined (ld) transplantation antigens, genes which control the structure of the immune response-associated antigens, human; the immune response genes which control the ability of an animal to respond immunologically to antigenic stimuli, and genes which determine the structure and/or level of the first four components of complement. Innate Immunity: Phagocytes and Antigen Presentation (MHC)
  • Human leukocyte antigen Antigen Substances that are recognized by the immune system and induce an immune reaction. Vaccination (HLA) subtypes
  • Genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure involved in T cells T cells Lymphocytes responsible for cell-mediated immunity. Two types have been identified – cytotoxic (t-lymphocytes, cytotoxic) and helper T-lymphocytes (t-lymphocytes, helper-inducer). They are formed when lymphocytes circulate through the thymus gland and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen. T cells: Types and Functions
• 45%–50% have concurrent polymyalgia rheumatica.

Pathophysiology

Giant cell arteritis (GCA) is caused by a complicated cascade of vascular inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation, damage, and dysfunctional repair:

• Triggering event has not been identified.
• Involves large- and medium-sized arteries Medium-Sized Arteries Kawasaki Disease:
  • Usually affecting the aorta Aorta The main trunk of the systemic arteries. Mediastinum and Great Vessels: Anatomy and its major branches
  • Common involvement of branches off the carotid and vertebral arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology
• Most notably involves the superficial temporal artery (STA; branch off the external carotid artery External carotid artery Branch of the common carotid artery which supplies the exterior of the head, the face, and the greater part of the neck. Carotid Arterial System: Anatomy)
• Mechanism:
  1. An antigen Antigen Substances that are recognized by the immune system and induce an immune reaction. Vaccination is sensed by dendritic cells Dendritic cells Specialized cells of the hematopoietic system that have branch-like extensions. They are found throughout the lymphatic system, and in non-lymphoid tissues such as skin and the epithelia of the intestinal, respiratory, and reproductive tracts. They trap and process antigens, and present them to T-cells, thereby stimulating cell-mediated immunity. They are different from the non-hematopoietic follicular dendritic cells, which have a similar morphology and immune system function, but with respect to humoral immunity (antibody production). Skin: Structure and Functions in the adventitia → recruits more dendritic cells Dendritic cells Specialized cells of the hematopoietic system that have branch-like extensions. They are found throughout the lymphatic system, and in non-lymphoid tissues such as skin and the epithelia of the intestinal, respiratory, and reproductive tracts. They trap and process antigens, and present them to T-cells, thereby stimulating cell-mediated immunity. They are different from the non-hematopoietic follicular dendritic cells, which have a similar morphology and immune system function, but with respect to humoral immunity (antibody production). Skin: Structure and Functions, lymphocytes Lymphocytes Lymphocytes are heterogeneous WBCs involved in immune response. Lymphocytes develop from the bone marrow, starting from hematopoietic stem cells (HSCs) and progressing to common lymphoid progenitors (CLPs). B and T lymphocytes and natural killer (NK) cells arise from the lineage. Lymphocytes: Histology, and macrophages Macrophages The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood monocytes. Main types are peritoneal macrophages; alveolar macrophages; histiocytes; kupffer cells of the liver; and osteoclasts. They may further differentiate within chronic inflammatory lesions to epithelioid cells or may fuse to form foreign body giant cells or langhans giant cells. Innate Immunity: Phagocytes and Antigen Presentation.
  2. Dendritic cells Dendritic cells Specialized cells of the hematopoietic system that have branch-like extensions. They are found throughout the lymphatic system, and in non-lymphoid tissues such as skin and the epithelia of the intestinal, respiratory, and reproductive tracts. They trap and process antigens, and present them to T-cells, thereby stimulating cell-mediated immunity. They are different from the non-hematopoietic follicular dendritic cells, which have a similar morphology and immune system function, but with respect to humoral immunity (antibody production). Skin: Structure and Functions process and present the antigens → cluster of differentiation 4 (CD4+) T cell activation T cell activation Adaptive Cell-mediated Immunity.
  3. CD4+ T cells T cells Lymphocytes responsible for cell-mediated immunity. Two types have been identified – cytotoxic (t-lymphocytes, cytotoxic) and helper T-lymphocytes (t-lymphocytes, helper-inducer). They are formed when lymphocytes circulate through the thymus gland and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen. T cells: Types and Functions proliferate → vascular inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation via activation of macrophages Macrophages The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood monocytes. Main types are peritoneal macrophages; alveolar macrophages; histiocytes; kupffer cells of the liver; and osteoclasts. They may further differentiate within chronic inflammatory lesions to epithelioid cells or may fuse to form foreign body giant cells or langhans giant cells. Innate Immunity: Phagocytes and Antigen Presentation.
  4. Medial layer is invaded by inflammatory cells → macrophages Macrophages The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood monocytes. Main types are peritoneal macrophages; alveolar macrophages; histiocytes; kupffer cells of the liver; and osteoclasts. They may further differentiate within chronic inflammatory lesions to epithelioid cells or may fuse to form foreign body giant cells or langhans giant cells. Innate Immunity: Phagocytes and Antigen Presentation undergo granulomatous organization (giant cells) → growth factors and metalloproteinases produced → loss of vascular smooth muscle cells and destruction of the internal elastic Elastic Connective Tissue: Histology lamina.
  5. Injured smooth muscle cells respond to this damage → myofibroblasts Myofibroblasts Spindle-shaped cells with characteristic contractile proteins and structures that contribute to the wound healing process. They occur in granulation tissue and also in pathological processes such as fibrosis. Hypertrophic and Keloid Scars differentiate, migrate toward the intimal layer, and produce extracellular matrix Extracellular matrix A meshwork-like substance found within the extracellular space and in association with the basement membrane of the cell surface. It promotes cellular proliferation and provides a supporting structure to which cells or cell lysates in culture dishes adhere. Hypertrophic and Keloid Scars proteins Proteins Linear polypeptides that are synthesized on ribosomes and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of amino acids determines the shape the polypeptide will take, during protein folding, and the function of the protein. Energy Homeostasis → intimal hyperplasia Hyperplasia An increase in the number of cells in a tissue or organ without tumor formation. It differs from hypertrophy, which is an increase in bulk without an increase in the number of cells. Cellular Adaptation and arterial occlusion → ischemic complications of the disease.

Clinical Presentation

Clinical manifestations

• Constitutional:
  • Fever Fever Fever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever 
  • Fatigue Fatigue The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli. Fibromyalgia 
  • Malaise Malaise Tick-borne Encephalitis Virus 
  • Weight loss Weight loss Decrease in existing body weight. Bariatric Surgery 
  • Anorexia Anorexia The lack or loss of appetite accompanied by an aversion to food and the inability to eat. It is the defining characteristic of the disorder anorexia nervosa. Anorexia Nervosa
• Head and neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess:
  • Headache Headache The symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders. Brain Abscess:
    • Occurs in ⅔ of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship
    • Varying severity and quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement
    • Localized to the temples and can be tender to the touch
    • Associated scalp tenderness
  • Jaw Jaw The jaw is made up of the mandible, which comprises the lower jaw, and the maxilla, which comprises the upper jaw. The mandible articulates with the temporal bone via the temporomandibular joint (TMJ). The 4 muscles of mastication produce the movements of the TMJ to ensure the efficient chewing of food. Jaw and Temporomandibular Joint: Anatomy claudication:
    • Occurs in about ½ of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship
    • Mandibular pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways or fatigue Fatigue The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli. Fibromyalgia during mastication Mastication The act and process of chewing and grinding food in the mouth. Jaw and Temporomandibular Joint: Anatomy that is relieved with rest
• Ophthalmic:
  • Transient vision Vision Ophthalmic Exam loss ( amaurosis fugax Amaurosis fugax Transient complete or partial monocular blindness due to retinal ischemia. This may be caused by emboli from the carotid artery (usually in association with carotid stenosis) and other locations that enter the central retinal artery. Carotid Artery Stenosis):
    • Results from loss of blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure to the eye
    • Typically monocular  
    • Painless, transient, and intermittent
    • Blurring, diplopia Diplopia A visual symptom in which a single object is perceived by the visual cortex as two objects rather than one. Disorders associated with this condition include refractive errors; strabismus; oculomotor nerve diseases; trochlear nerve diseases; abducens nerve diseases; and diseases of the brain stem and occipital lobe. Myasthenia Gravis, or vision Vision Ophthalmic Exam loss
  • Permanent vision Vision Ophthalmic Exam loss:
    • Most dreaded complication
    • Due to anterior or posterior ischemic optic neuropathy Neuropathy Leprosy, central retinal artery occlusion Retinal Artery Occlusion Retinal Vessel Occlusion, or cerebral ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage 
    • Partial or complete vision Vision Ophthalmic Exam loss that is painless and sudden
    • May affect 1 or both eyes Both Eyes Refractive Errors
    • Rarely reversible
• Musculoskeletal:
  • Polymyalgia rheumatica:
    • Aching and morning stiffness in the proximal muscles and joints
    • Shoulders, hip girdles, neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess, and torso affected

Physical exam

• Cardiovascular:
  • Diminished pulses 
  • Temporal artery tenderness and enlargement
  • Discrepant blood pressure in arms → subclavian artery involvement
  • Bruits 
  • Aortic regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD) heart murmur → suspect an ascending aortic aneurysm Ascending aortic aneurysm Thoracic Aortic Aneurysms
• Fundoscopy Fundoscopy Cranial Nerve Palsies:
  • Can be entirely normal with transient symptoms
  • Retinal ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage → cotton-wool spots in the retina Retina The ten-layered nervous tissue membrane of the eye. It is continuous with the optic nerve and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the choroid and the inner surface with the vitreous body. The outermost layer is pigmented, whereas the inner nine layers are transparent. Eye: Anatomy
  • Anterior ischemic optic neuropathy Neuropathy Leprosy (loss of blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure to the anterior portion of the optic nerve Optic nerve The 2nd cranial nerve which conveys visual information from the retina to the brain. The nerve carries the axons of the retinal ganglion cells which sort at the optic chiasm and continue via the optic tracts to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the superior colliculi and the suprachiasmatic nuclei. Though known as the second cranial nerve, it is considered part of the central nervous system. The 12 Cranial Nerves: Overview and Functions) → swollen, pale disc and blurred margins of the retina Retina The ten-layered nervous tissue membrane of the eye. It is continuous with the optic nerve and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the choroid and the inner surface with the vitreous body. The outermost layer is pigmented, whereas the inner nine layers are transparent. Eye: Anatomy
• Musculoskeletal:
  • Limited shoulder, neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess, and hip range of motion Range of motion The distance and direction to which a bone joint can be extended. Range of motion is a function of the condition of the joints, muscles, and connective tissues involved. Joint flexibility can be improved through appropriate muscle strength exercises. Examination of the Upper Limbs
  • Wrist and metacarpophalangeal synovitis Synovitis Inflammation of the synovial membrane. Rheumatoid Arthritis

Diagnosis

Diagnostic algorithm

Diagnostic modalities

• 1st, check laboratory studies:
  • ESR ESR Soft Tissue Abscess and CRP:
    • Almost always elevated
    • Non-specific
  • Complete blood count:
    • Normochromic anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types
    • Reactive thrombocytosis
    • Normal or minimally elevated leukocytes Leukocytes White blood cells. These include granular leukocytes (basophils; eosinophils; and neutrophils) as well as non-granular leukocytes (lymphocytes and monocytes). White Myeloid Cells: Histology
  • Liver Liver The liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy function panel:
    • Elevated alkaline phosphatase Alkaline Phosphatase An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. Osteosarcoma
    • Decreased albumin Albumin Serum albumin from humans. It is an essential carrier of both endogenous substances, such as fatty acids and bilirubin, and of xenobiotics in the blood. Liver Function Tests
• Next steps:
  • Temporal artery biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma (gold standard): 
    • Should be performed in all patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with suspected GCA
    • Lesions are segmental, so diagnosis requires a biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma of a long vessel segment.
    • Histopathology findings:
      • Panarteritis
      • Giant cells
      • Fragmented internal elastic Elastic Connective Tissue: Histology lamina
    • If negative, a contralateral temporal artery biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma should be considered.
  • Color Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) ultrasound:
    • Possible non-invasive alternative for temporal artery biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma, but is operator dependent
    • Should evaluate the vessels of the head, neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess, and upper extremities
    • “ Halo sign Halo sign Aspergillus/Aspergillosis” (darkened area surrounding the vascular lumen from mural edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema) is highly specific.
• If the above work-up is not diagnostic, consider evaluation for large-vessel involvement:
  • Color Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) ultrasound of axillary and subclavian arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology
  • Computed tomography with angiography Angiography Radiography of blood vessels after injection of a contrast medium. Cardiac Surgery ( CTA CTA A non-invasive method that uses a ct scanner for capturing images of blood vessels and tissues. A contrast material is injected, which helps produce detailed images that aid in diagnosing vascular diseases. Pulmonary Function Tests)
  • Magnetic resonance imaging (MRI) or magnetic resonance angiography Angiography Radiography of blood vessels after injection of a contrast medium. Cardiac Surgery ( MRA MRA Imaging of the Heart and Great Vessels)
  • Positron emission tomography ( PET PET An imaging technique that combines a positron-emission tomography (PET) scanner and a ct X ray scanner. This establishes a precise anatomic localization in the same session. Nuclear Imaging)

Management

Treatment options

• High-dose systemic glucocorticoids Systemic Glucocorticoids Glucocorticoids:
  • Mainstay of treatment, and should be initiated promptly if there is a strong suspicion of GCA
  • Without vision Vision Ophthalmic Exam loss: prednisone Prednisone A synthetic anti-inflammatory glucocorticoid derived from cortisone. It is biologically inert and converted to prednisolone in the liver. Immunosuppressants
  • With vision Vision Ophthalmic Exam loss: methylprednisolone Methylprednisolone A prednisolone derivative with similar anti-inflammatory action. Immunosuppressants
  • Tapered slowly over 6–12 months
• Adjunctive treatment:
  • May be used when glucocorticoids Glucocorticoids Glucocorticoids are a class within the corticosteroid family. Glucocorticoids are chemically and functionally similar to endogenous cortisol. There are a wide array of indications, which primarily benefit from the antiinflammatory and immunosuppressive effects of this class of drugs. Glucocorticoids are not tolerated
  • Tocilizumab Tocilizumab Immunosuppressants
  • Methotrexate Methotrexate An antineoplastic antimetabolite with immunosuppressant properties. It is an inhibitor of tetrahydrofolate dehydrogenase and prevents the formation of tetrahydrofolate, necessary for synthesis of thymidylate, an essential component of DNA. Antimetabolite Chemotherapy

General measures

• Rheumatology consultation
• Monthly routine follow-up:
  • Monitor symptoms and perform examination.
  • Can trend ESR ESR Soft Tissue Abscess and CRP
• Tuberculosis Tuberculosis Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex bacteria. The bacteria usually attack the lungs but can also damage other parts of the body. Approximately 30% of people around the world are infected with this pathogen, with the majority harboring a latent infection. Tuberculosis spreads through the air when a person with active pulmonary infection coughs or sneezes. Tuberculosis screening Screening Preoperative Care
• Immunizations for influenza Influenza Influenza viruses are members of the Orthomyxoviridae family and the causative organisms of influenza, a highly contagious febrile respiratory disease. There are 3 primary influenza viruses (A, B, and C) and various subtypes, which are classified based on their virulent surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza typically presents with a fever, myalgia, headache, and symptoms of an upper respiratory infection. Influenza Viruses/Influenza and pneumococcal pneumonia Pneumonia Pneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy. Pneumonia
• Antiplatelet therapy in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with atherosclerosis Atherosclerosis Atherosclerosis is a common form of arterial disease in which lipid deposition forms a plaque in the blood vessel walls. Atherosclerosis is an incurable disease, for which there are clearly defined risk factors that often can be reduced through a change in lifestyle and behavior of the patient. Atherosclerosis: A proton pump Pump ACES and RUSH: Resuscitation Ultrasound Protocols inhibitor should be considered because aspirin Aspirin The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. Nonsteroidal Antiinflammatory Drugs (NSAIDs) use, glucocorticoids Glucocorticoids Glucocorticoids are a class within the corticosteroid family. Glucocorticoids are chemically and functionally similar to endogenous cortisol. There are a wide array of indications, which primarily benefit from the antiinflammatory and immunosuppressive effects of this class of drugs. Glucocorticoids, and age will increase the risk for gastrointestinal bleeding Gastrointestinal bleeding Gastrointestinal bleeding (GIB) is a symptom of multiple diseases within the gastrointestinal (GI) tract. Gastrointestinal bleeding is designated as upper or lower based on the etiology’s location to the ligament of Treitz. Depending on the location of the bleeding, the patient may present with hematemesis (vomiting blood), melena (black, tarry stool), or hematochezia (fresh blood in stools). Gastrointestinal Bleeding.
• Osteoporosis Osteoporosis Osteoporosis refers to a decrease in bone mass and density leading to an increased number of fractures. There are 2 forms of osteoporosis: primary, which is commonly postmenopausal or senile; and secondary, which is a manifestation of immobilization, underlying medical disorders, or long-term use of certain medications. Osteoporosis prevention with calcium Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Electrolytes and vitamin D Vitamin D A vitamin that includes both cholecalciferols and ergocalciferols, which have the common effect of preventing or curing rickets in animals. It can also be viewed as a hormone since it can be formed in skin by action of ultraviolet rays upon the precursors, 7-dehydrocholesterol and ergosterol, and acts on vitamin D receptors to regulate calcium in opposition to parathyroid hormone. Fat-soluble Vitamins and their Deficiencies
• Monitor bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types density.

Differential Diagnosis

• Stroke: disease in which poor blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure to the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification results in cell death Cell death Injurious stimuli trigger the process of cellular adaptation, whereby cells respond to withstand the harmful changes in their environment. Overwhelmed adaptive mechanisms lead to cell injury. Mild stimuli produce reversible injury. If the stimulus is severe or persistent, injury becomes irreversible. Apoptosis is programmed cell death, a mechanism with both physiologic and pathologic effects. Cell Injury and Death. There are 2 types: ischemic stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke due to lack of blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure, and hemorrhagic stroke Hemorrhagic stroke Stroke due to rupture of a weakened blood vessel in the brain (e.g., cerebral hemispheres; cerebellum; subarachnoid space). Subarachnoid Hemorrhage due to bleeding. Symptoms include focal weakness, numbness, loss of vision Vision Ophthalmic Exam, dysarthria Dysarthria Disorders of speech articulation caused by imperfect coordination of pharynx, larynx, tongue, or face muscles. This may result from cranial nerve diseases; neuromuscular diseases; cerebellar diseases; basal ganglia diseases; brain stem diseases; or diseases of the corticobulbar tracts. The cortical language centers are intact in this condition. Wilson Disease, and headache Headache The symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders. Brain Abscess. Computed tomography and MRI of the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification are used for the diagnosis, and will differentiate stroke from GCA.
• Migraine Migraine Migraine headache is a primary headache disorder and is among the most prevalent disorders in the world. Migraine is characterized by episodic, moderate to severe headaches that may be associated with increased sensitivity to light and sound, as well as nausea and/or vomiting. Migraine Headache: characterized by recurrent headaches that are moderate to severe, typically affecting ½ of the head, and pulsating in nature. Associated symptoms include nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics, vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, and sensitivity to light, sound, or smell Smell The sense of smell, or olfaction, begins in a small area on the roof of the nasal cavity, which is covered in specialized mucosa. From there, the olfactory nerve transmits the sensory perception of smell via the olfactory pathway. This pathway is composed of the olfactory cells and bulb, the tractus and striae olfactoriae, and the primary olfactory cortex and amygdala. Olfaction: Anatomy. Diagnosis is clinical, based on the history and physical exam. Laboratory and imaging studies will be unremarkable. The history, physical exam, and low inflammatory markers will help differentiate migraine Migraine Migraine headache is a primary headache disorder and is among the most prevalent disorders in the world. Migraine is characterized by episodic, moderate to severe headaches that may be associated with increased sensitivity to light and sound, as well as nausea and/or vomiting. Migraine Headache from GCA.
• Glaucoma Glaucoma Glaucoma is an optic neuropathy characterized by typical visual field defects and optic nerve atrophy seen as optic disc cupping on examination. The acute form of glaucoma is a medical emergency. Glaucoma is often, but not always, caused by increased intraocular pressure (IOP). Glaucoma: An increase in intraocular pressure Intraocular Pressure The pressure of the fluids in the eye. Ophthalmic Exam damages the optic nerve Optic nerve The 2nd cranial nerve which conveys visual information from the retina to the brain. The nerve carries the axons of the retinal ganglion cells which sort at the optic chiasm and continue via the optic tracts to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the superior colliculi and the suprachiasmatic nuclei. Though known as the second cranial nerve, it is considered part of the central nervous system. The 12 Cranial Nerves: Overview and Functions and causes blindness Blindness The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of eye diseases; optic nerve diseases; optic chiasm diseases; or brain diseases affecting the visual pathways or occipital lobe. Retinopathy of Prematurity. Angle-closure glaucoma Angle-Closure Glaucoma Glaucoma symptoms include blurred vision Blurred Vision Retinal Detachment, halos around light, severe eye pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, headache Headache The symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders. Brain Abscess, nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics, and vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia. Diagnosis is made by an ophthalmology exam and intraocular pressure Intraocular Pressure The pressure of the fluids in the eye. Ophthalmic Exam measurements, which will differentiate glaucoma Glaucoma Glaucoma is an optic neuropathy characterized by typical visual field defects and optic nerve atrophy seen as optic disc cupping on examination. The acute form of glaucoma is a medical emergency. Glaucoma is often, but not always, caused by increased intraocular pressure (IOP). Glaucoma from GCA.
• Takayasu’s arteritis: a large-vessel, granulomatous vasculitis Vasculitis Inflammation of any one of the blood vessels, including the arteries; veins; and rest of the vasculature system in the body. Systemic Lupus Erythematosus that primarily affects the aorta Aorta The main trunk of the systemic arteries. Mediastinum and Great Vessels: Anatomy and its primary branches. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are often young or middle-aged women. Signs and symptoms include tenderness of the carotid artery, limb claudication, and absent or weak pulses. Elevated inflammatory markers and CTA CTA A non-invasive method that uses a ct scanner for capturing images of blood vessels and tissues. A contrast material is injected, which helps produce detailed images that aid in diagnosing vascular diseases. Pulmonary Function Tests of the aorta Aorta The main trunk of the systemic arteries. Mediastinum and Great Vessels: Anatomy can aid in the diagnosis. Treatment includes glucocorticoids Glucocorticoids Glucocorticoids are a class within the corticosteroid family. Glucocorticoids are chemically and functionally similar to endogenous cortisol. There are a wide array of indications, which primarily benefit from the antiinflammatory and immunosuppressive effects of this class of drugs. Glucocorticoids and glucocorticoid-sparing agents. The patient’s demographics, history, and exam findings will differentiate Takayasu’s arteritis from GCA. 
• Non-arteritic anterior ischemic optic neuropathy Neuropathy Leprosy: an idiopathic Idiopathic Dermatomyositis, ischemic injury to the optic nerve Optic nerve The 2nd cranial nerve which conveys visual information from the retina to the brain. The nerve carries the axons of the retinal ganglion cells which sort at the optic chiasm and continue via the optic tracts to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the superior colliculi and the suprachiasmatic nuclei. Though known as the second cranial nerve, it is considered part of the central nervous system. The 12 Cranial Nerves: Overview and Functions. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with sudden, painless, and monocular vision Vision Ophthalmic Exam loss. A fundoscopic exam Fundoscopic Exam Head and Neck Examination will show optic disc Optic disc The portion of the optic nerve seen in the fundus with the ophthalmoscope. It is formed by the meeting of all the retinal ganglion cell axons as they enter the optic nerve. Eye: Anatomy swelling Swelling Inflammation. Giant cell arteritis should be considered in these individuals, and can be ruled out with normal inflammatory markers. There is no known effective treatment, but patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are generally placed on aspirin Aspirin The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. Nonsteroidal Antiinflammatory Drugs (NSAIDs).