Ehlers-Danlos Syndrome

Overview

Definition

Ehlers-Danlos syndrome (EDS) is a group of 13 inherited connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology disorders of collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology processing or synthesis Synthesis Polymerase Chain Reaction (PCR). The syndrome is clinically heterogeneous and can affect the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions, joints, blood vessels, and other tissues and is characterized by the following:

• Joint hypermobility
• Cutaneous hyperextensibility/fragility
• Connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology hyperextensibility/fragility
• Delayed wound healing Wound healing Wound healing is a physiological process involving tissue repair in response to injury. It involves a complex interaction of various cell types, cytokines, and inflammatory mediators. Wound healing stages include hemostasis, inflammation, granulation, and remodeling. Wound Healing/ scarring Scarring Inflammation

Epidemiology

• The combined prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency of all types is reported to be 1 case per 5000 people.
• The classical and hypermobility subtypes of EDS account for the majority of cases.
• 50% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship have an affected parent.
• Caucasians more commonly affected than other races
• Women = men
• Dermatosparaxis type more common in Ashkenazi Jews

Etiology and pathophysiology

• Connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology disorder involving genetic defects in the collagens (a family of 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)
• Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology alterations found in the reticular dermis Dermis A layer of vascularized connective tissue underneath the epidermis. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are sweat glands; hair follicles; and sebaceous glands. Skin: Structure and Functions:
  • Irregularities in fibril diameter
  • Irregular collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology shapes
• Multiple gene Gene 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. Basic Terms of Genetics mutations have been found in association with EDS.
• The genetic basis is known for the majority of EDS types.
• EDS can be inherited as a dominant or recessive genetic condition.

Classification

This list of classifications is not exhaustive; it includes the most common, clinically significant subtypes.

• Classical type (cEDS): 
  • Autosomal dominant inheritance Autosomal dominant inheritance Autosomal Recessive and Autosomal Dominant Inheritance
  • COL5A1 and COL5A2 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 mutated
  • Type I collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology fibrils affected
• Classical-like (clEDS): 
  • Autosomal recessive inheritance Autosomal recessive inheritance Autosomal Recessive and Autosomal Dominant Inheritance
  • TNXB gene Gene 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. Basic Terms of Genetics mutated
  • → Tenascin X deficiency
  • Integrity of the scaffold in which the collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology lays down affected
• Hypermobility type (hEDS): 
  • Autosomal dominant inheritance Autosomal dominant inheritance Autosomal Recessive and Autosomal Dominant Inheritance
  • Unknown gene mutation Gene Mutation Myotonic Dystrophies
  •  Integrity of the scaffold in which the collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology lays down affected
• Cardiac valvular type (cvEDS):  
  • Autosomal recessive inheritance Autosomal recessive inheritance Autosomal Recessive and Autosomal Dominant Inheritance
  •  COL1A2 gene mutation Gene Mutation Myotonic Dystrophies
  • Type I collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology fibrils affected
• Vascular type (vEDS): 
  • Autosomal dominant inheritance Autosomal dominant inheritance Autosomal Recessive and Autosomal Dominant Inheritance
  • COL3A1 gene mutation Gene Mutation Myotonic Dystrophies
  • Type III procollagen affected

Clinical Presentation

History

• Family history Family History Adult Health Maintenance:
  • Autosomal dominant inheritance Autosomal dominant inheritance Autosomal Recessive and Autosomal Dominant Inheritance pattern
  • Autosomal recessive inheritance Autosomal recessive inheritance Autosomal Recessive and Autosomal Dominant Inheritance pattern
• Initial presenting symptoms:
  • Joint symptoms (most commonly dislocation)
  • Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions symptoms

Exam findings

Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions:

• Hyperextensible skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions:
  • Defined as skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions stretch ≥ 4 cm at a neutral site ( neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess or ventral aspect of forearm Forearm The forearm is the region of the upper limb between the elbow and the wrist. The term “forearm” is used in anatomy to distinguish this area from the arm, a term that is commonly used to describe the entire upper limb. The forearm consists of 2 long bones (the radius and the ulna), the interosseous membrane, and multiple arteries, nerves, and muscles. Forearm: Anatomy) until resistance Resistance Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow. Ventilation: Mechanics of Breathing is felt
  • Hyperextensible skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions observed in:
    • cEDS
    • clEDS
    • Kyphoscoliotic EDS
  • Present in children, but 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 increases with age
• Extensive/abnormal scarring Scarring Inflammation observed in:
  • clEDS 
  • Kyphoscoliotic EDS
• Tendency to bruise easily and heal slowly
• Abnormal/ hypertrophic scarring Hypertrophic Scarring Acne Vulgaris
• Thin/translucent skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions

Musculoskeletal:

• Joint hypermobility:
  • Joint dislocations/subluxations are common in most forms of EDS.
  • Often self-reduced by the patient or resolve spontaneously
  • Most common sites of subluxation Subluxation Radial Head Subluxation (Nursemaid’s Elbow)/dislocation:
    • Shoulder
    • Patella Patella The flat, triangular bone situated at the anterior part of the knee. Knee Joint: Anatomy
    • Temporomandibular joint
• Skeletal abnormalities:
  • Pectus excavatum Pectus Excavatum Cardiovascular Examination
  • Kyphoscoliosis Kyphoscoliosis Osteomalacia and Rickets
  • Pes PES Removal of plasma and replacement with various fluids, e.g., fresh frozen plasma, plasma protein fractions (ppf), albumin preparations, dextran solutions, saline. Used in treatment of autoimmune diseases, immune complex diseases, diseases of excess plasma factors, and other conditions. Thrombotic Thrombocytopenic Purpura planus
  • High-arched palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy
• Skeletal/joint abnormality complications:
  • Recurrent subluxations/dislocations
  • Early degenerative arthritis Arthritis Acute or chronic inflammation of joints. Osteoarthritis
  • Complex regional pain Regional Pain Complex Regional Pain Syndrome (CRPS) syndrome
• Muscular hypotonia Hypotonia Duchenne Muscular Dystrophy

Cardiovascular:

• vEDS (and in some rarer types of EDS): 
  • Aneurysms/pseudoaneurysms
  • Dilation of the aortic root
  • Arterial dissection Arterial dissection Arterial dissection is a violation of the structural integrity of the arterial wall that results in blood accumulating between the layers. Dissection of the Carotid and Vertebral Arteries/rupture 
• Heart valve defects (particularly mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy prolapse)

Pulmonary:

• Spontaneous pneumothorax Pneumothorax A pneumothorax is a life-threatening condition in which air collects in the pleural space, causing partial or full collapse of the lung. A pneumothorax can be traumatic or spontaneous. Patients present with a sudden onset of sharp chest pain, dyspnea, and diminished breath sounds on exam. Pneumothorax
• Emphysema Emphysema Enlargement of air spaces distal to the terminal bronchioles where gas-exchange normally takes place. This is usually due to destruction of the alveolar wall. Pulmonary emphysema can be classified by the location and distribution of the lesions. Chronic Obstructive Pulmonary Disease (COPD)

GI:

• Propensity for development of:
  • Hernias
  • Fistulas
  • Diverticula
• Spontaneous rupture of hollow organs
• Dysmotility

Ophthalmic:

• Blue sclerae Blue Sclerae Osteogenesis Imperfecta
• Scleral/corneal rupture with mild trauma
• Retinal detachment Retinal detachment Retinal detachment is the separation of the neurosensory retina from the retinal pigmented epithelium and choroid. Rhegmatogenous retinal detachment, the most common type, stems from a break in the retina, allowing fluid to accumulate in the subretinal space. Retinal Detachment
• Myopia Myopia Refractive Errors

Obstetric/gynecologic:

• Pelvic floor Pelvic floor Soft tissue formed mainly by the pelvic diaphragm, which is composed of the two levator ani and two coccygeus muscles. The pelvic diaphragm lies just below the pelvic aperture (outlet) and separates the pelvic cavity from the perineum. It extends between the pubic bone anteriorly and the coccyx posteriorly. Vagina, Vulva, and Pelvic Floor: Anatomy weakness:
  • Vaginal prolapse
  • Uterine prolapse Uterine prolapse Downward displacement of the uterus. It is classified in various degrees: in the first degree the uterine cervix is within the vaginal orifice; in the second degree the cervix is outside the orifice; in the third degree the entire uterus is outside the orifice. Pelvic Organ Prolapse
  • Rectal prolapse Rectal prolapse Rectal prolapse, also known as rectal procidentia, is the protrusion of rectal tissue through the anus. The tissue may include just the mucosa or the full thickness of the rectal wall. Common risk factors include chronic straining, constipation, bowel motility disorders, and weakening of the pelvic floor muscles. Rectal Prolapse
• Uterine fragility:
  • Spontaneous uterine rupture Uterine Rupture A complete separation or tear in the wall of the uterus with or without expulsion of the fetus. It may be due to injuries, multiple pregnancies, large fetus, previous scarring, or obstruction. Antepartum Hemorrhage
  • High-risk pregnancy High-Risk Pregnancy Prenatal Care

Miscellaneous:

• Mental development is normal.
• Dental/gingival abnormalities

Diagnosis

Ehlers-Danlos syndrome is generally diagnosed on the basis of patient history and clinical findings.

• Initial evaluation:
  • Major and minor diagnostic criteria exist for each EDS subtype. 
  • Beighton Hypermobility Scale Scale Dermatologic Examination:
    • Set of maneuvers used to detect evidence of joint hypermobility
    • Scoring system most often used in epidemiologic research Research Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. Conflict of Interest 
    • A score ≥ 5 of the maximum of 9 points is used to define hypermobility in criteria for EDS.
  • Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions hyperextensibility can be examined by carefully pulling up the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions at a neutral site until the point of resistance Resistance Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow. Ventilation: Mechanics of Breathing.
  • Baseline echocardiography Echocardiography Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic. Tricuspid Valve Atresia (TVA) to rule out aortic dilatation
• Genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies for the identification Identification Defense Mechanisms of EDS subtype
• Consider clotting studies to rule out hypocoagulable Hypocoagulable Hypocoagulable conditions, also known as bleeding disorders or bleeding diathesis, are a diverse group of diseases that result in abnormal hemostasis. Physiologic hemostasis is dependent on the integrity of endothelial cells, subendothelial matrix, platelets, and coagulation factors. The hypocoagulable states result from abnormalities in one or more of these contributors, resulting in ineffective thrombosis and bleeding. Hypocoagulable Conditions state as cause of bruising.

Management and Prognosis

Management

• No specific cure
• Patient education is key:
  • Prevention/early recognition of complications 
  • Proper screening Screening Preoperative Care for complications based on subtype
  • Prenatal planning
• Consider referral:
  • Geneticist 
  • Ophthalmologist
  • Cardiologist
  • Pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways specialist
  • Orthopedist
  • Rheumatologist
  • Dermatologist
  • Obstetrician/gynecologist
  • Psychiatrist/behavioral health
• Ascorbic acid ( vitamin C Vitamin C A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant. Water-soluble Vitamins and their Deficiencies) supplementation:
  • Critical cofactor for collagen Collagen A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin; connective tissue; and the organic substance of bones (bone and bones) and teeth (tooth). Connective Tissue: Histology fibril synthesis Synthesis Polymerase Chain Reaction (PCR)
  • May aid in healing/prevention of scarring Scarring Inflammation
• 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 supplementation to maintain 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
• Avoid/ limit Limit A value (e.g., pressure or time) that should not be exceeded and which is specified by the operator to protect the lung Invasive Mechanical Ventilation:
  • Contact sports
  • High-impact sports
  • Heavy lifting
• Low-impact muscle-strengthening program
• Appropriate use of bracing/assistive devices
• Obstetric planning/counseling 
• Support group for EDS

Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas

• Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas varies depending on subtype.
• Generally, the mortality Mortality All deaths reported in a given population. Measures of Health Status of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with the classical and hypermobility subtypes is not impacted by the disease.
• The vascular and kyphoscoliotic subtypes have a higher risk of complications that shorten life expectancy Life expectancy Based on known statistical data, the number of years which any person of a given age may reasonably expected to live. Population Pyramids.

Clinical Relevance

Differential diagnosis

• Marfan syndrome Marfan syndrome Marfan syndrome is a genetic condition with autosomal dominant inheritance. Marfan syndrome affects the elasticity of connective tissues throughout the body, most notably in the cardiovascular, ocular, and musculoskeletal systems. Marfan Syndrome: autosomal dominant Autosomal dominant Autosomal inheritance, both dominant and recessive, refers to the transmission of genes from the 22 autosomal chromosomes. Autosomal dominant diseases are expressed when only 1 copy of the dominant allele is inherited. Autosomal Recessive and Autosomal Dominant Inheritance connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology disorder that affects the microfibrils and elastin in connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology and also presents with joint hypermobility. Marfan syndrome Marfan syndrome Marfan syndrome is a genetic condition with autosomal dominant inheritance. Marfan syndrome affects the elasticity of connective tissues throughout the body, most notably in the cardiovascular, ocular, and musculoskeletal systems. Marfan Syndrome can be distinguished clinically (tall stature, long limbs) and confirmed by genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies. Monitoring for cardiovascular complications ( aortic dissection Aortic dissection Aortic dissection occurs due to shearing stress from pulsatile pressure causing a tear in the tunica intima of the aortic wall. This tear allows blood to flow into the media, creating a “false lumen.” Aortic dissection is most commonly caused by uncontrolled hypertension. Aortic Dissection, valvular heart disease) is the keystone of management, as these are the main causes of mortality Mortality All deaths reported in a given population. Measures of Health Status.
• Loeys-Dietz syndrome: autosomal dominant Autosomal dominant Autosomal inheritance, both dominant and recessive, refers to the transmission of genes from the 22 autosomal chromosomes. Autosomal dominant diseases are expressed when only 1 copy of the dominant allele is inherited. Autosomal Recessive and Autosomal Dominant Inheritance connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology disorder characterized by tortuosity of arterial vessels, widely spaced eyes ( hypertelorism Hypertelorism Abnormal increase in the interorbital distance due to overdevelopment of the lesser wings of the sphenoid. DiGeorge Syndrome), a wide/split posterior of the soft palate Soft palate A movable fold suspended from the posterior border of the hard palate. The uvula hangs from the middle of the lower border. Palate: Anatomy of the mouth, and aortic aneurysms. The condition is diagnosed clinically and confirmed by genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies. Management is centered around the prevention of vascular complications.

Related conditions

• Cutis laxa (elastolysis): rare, inherited, or acquired connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology disorder in which the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions becomes inelastic and hangs loosely in folds.
• Pseudoxanthoma elasticum: rare genetic disorder characterized by elastorrhexis (progressive calcification and fragmentation Fragmentation Chronic Apophyseal Injury of elastic Elastic Connective Tissue: Histology fibers) that predominantly affects the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions, cardiovascular system, and 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.
• Osteogenesis imperfecta Osteogenesis imperfecta Osteogenesis imperfecta (OI), or “brittle bone disease,” is a rare genetic connective tissue disorder characterized by severe bone fragility. Although OI is considered a single disease, OI includes over 16 genotypes and clinical phenotypes with differing symptom severity. Osteogenesis Imperfecta (OI) type I: genetic disorder characterized by bones that break easily, muscle weakness, joint laxity, scoliosis Scoliosis Scoliosis is a structural alteration of the vertebral column characterized by a lateral spinal curvature of greater than 10 degrees in the coronal plane. Scoliosis can be classified as idiopathic (in most cases) or secondary to underlying conditions. Scoliosis, brittle teeth Teeth Normally, an adult has 32 teeth: 16 maxillary and 16 mandibular. These teeth are divided into 4 quadrants with 8 teeth each. Each quadrant consists of 2 incisors (dentes incisivi), 1 canine (dens caninus), 2 premolars (dentes premolares), and 3 molars (dentes molares). Teeth are composed of enamel, dentin, and dental cement. Teeth: Anatomy, and hearing loss Hearing loss Hearing loss, also known as hearing impairment, is any degree of impairment in the ability to apprehend sound as determined by audiometry to be below normal hearing thresholds. Clinical presentation may occur at birth or as a gradual loss of hearing with age, including a short-term or sudden loss at any point. Hearing Loss.
• Child abuse Child abuse Child abuse is an act or failure to act that results in harm to a child’s health or development. The abuse encompasses neglect as well as physical, sexual, and emotional harm. Seen in all subsets of society, child abuse is a cause of significant morbidity and mortality in the pediatric population. Child Abuse: Ehlers-Danlos syndrome may resemble child abuse Child abuse Child abuse is an act or failure to act that results in harm to a child’s health or development. The abuse encompasses neglect as well as physical, sexual, and emotional harm. Seen in all subsets of society, child abuse is a cause of significant morbidity and mortality in the pediatric population. Child Abuse in some patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship, a potential medicolegal concern and challenge.