Blepharitis (Clinical)

Overview

Definition^[1-5]

• 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 of the eyelid margin
• Chronic recurrent irritation can lead to eyelid scarring Scarring Inflammation and affect the surrounding structures ( cornea Cornea The transparent anterior portion of the fibrous coat of the eye consisting of five layers: stratified squamous corneal epithelium; bowman membrane; corneal stroma; descemet membrane; and mesenchymal corneal endothelium. It serves as the first refracting medium of the eye. Eye: Anatomy and conjunctiva Conjunctiva The mucous membrane that covers the posterior surface of the eyelids and the anterior pericorneal surface of the eyeball. Eye: Anatomy).

Anatomy^[1]

• Eyelids Eyelids Each of the upper and lower folds of skin which cover the eye when closed. Blepharitis protect the eyes from injury and light. 
• Eyelid layers (from superficial to deep):
  • 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
  • Loose subcutaneous tissue Subcutaneous tissue Loose connective tissue lying under the dermis, which binds skin loosely to subjacent tissues. It may contain a pad of adipocytes, which vary in number according to the area of the body and vary in size according to the nutritional state. Soft Tissue Abscess
  • Orbicularis oculi Orbicularis oculi Facial Muscles: Anatomy muscle:
    • Closes the eyelids Eyelids Each of the upper and lower folds of skin which cover the eye when closed. Blepharitis
    • Assists in tear drainage
  • Tarsal plate:
    • 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 that gives structural rigidity Rigidity Continuous involuntary sustained muscle contraction which is often a manifestation of basal ganglia diseases. When an affected muscle is passively stretched, the degree of resistance remains constant regardless of the rate at which the muscle is stretched. This feature helps to distinguish rigidity from muscle spasticity. Megacolon to the eyelid
    • Contains the meibomian glands
    • The levator palpebrae superioris Levator palpebrae superioris Orbit and Extraocular Muscles: Anatomy muscle is inserted into the superior tarsal plate.
  • Palpebral conjunctiva Palpebral Conjunctiva Blepharitis: covers the inner surface of eyelids Eyelids Each of the upper and lower folds of skin which cover the eye when closed. Blepharitis
• Eyelid glands Eyelid Glands Blepharitis:
  • Meibomian glands:
    • Modified sebaceous glands with openings behind the eyelashes
    • Meibum Meibum Blepharitis (lipid-rich secretion Secretion Coagulation Studies): prevents evaporation of tears and evens out tear film over the surface of the eye
  • Gland of Moll Gland of Moll Blepharitis:
    • Modified sweat glands Modified Sweat Glands Hordeolum (Stye) 
    • Orifice between adjacent lashes
  • Gland of Zeis:
    • Sebaceous gland Sebaceous Gland Small, sacculated organs found within the dermis. Each gland has a single duct that emerges from a cluster of oval alveoli. Each alveolus consists of a transparent basement membrane enclosing epithelial cells. The ducts from most sebaceous glands open into a hair follicle, but some open on the general surface of the skin. Sebaceous glands secrete sebum. Hordeolum (Stye) 
    • Orifice into the eyelash follicle
• Eyelashes:
  • Protect the eyes from particles or debris, which can cause infection or injury
  • Arranged in double or triple rows at the mucocutaneous junction

Types^[1,4,5]

• Categorized based on anatomical location but often overlap 
• Posterior blepharitis Posterior Blepharitis Blepharitis: 
  • More common
  • Primarily caused by meibomian gland Meibomian Gland Chalazion dysfunction/blockage
  • Involves the meibomian glands, tarsal plate, and blepharo-conjunctival junction
• Anterior blepharitis Anterior Blepharitis Blepharitis: 
  • 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 around the eyelid 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, base of the eyelashes, and lash follicles
  • Variants:
    • Staphylococcal blepharitis Staphylococcal Blepharitis Blepharitis: crust Crust Dried exudate of body fluids (blood, pus, or sebum) on an area of damaged skin Secondary Skin Lesions around eyelashes caused by Staphylococcus aureus Staphylococcus aureus Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications. Brain Abscess and coagulase-negative staphylococci Coagulase-negative staphylococci Staphylococcus
    • Seborrheic blepharitis Seborrheic Blepharitis Blepharitis: greasy scales Scales Dry or greasy masses of keratin that represent thickened stratum corneum. Secondary Skin Lesions and crust Crust Dried exudate of body fluids (blood, pus, or sebum) on an area of damaged skin Secondary Skin Lesions around the base of eyelids Eyelids Each of the upper and lower folds of skin which cover the eye when closed. Blepharitis with flaky 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 changes

Pathophysiology and Etiology

Pathophysiology^[1,3-5]

• Posterior blepharitis Posterior Blepharitis Blepharitis:
  • Functional abnormality of the meibomian glands → altered meibum Meibum Blepharitis composition
  • Wax-like secretions can block gland orifices.
  • Stagnant material and altered lipid composition → promotes bacterial growth → 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
  • Chronic inflammation Chronic Inflammation Inflammation damages eyelid structure and further facilitates gland dysfunction.
• Anterior blepharitis Anterior Blepharitis Blepharitis: mechanism not fully understood but pathways include
  • Direct infection from Staphylococcus Staphylococcus Staphylococcus is a medically important genera of Gram-positive, aerobic cocci. These bacteria form clusters resembling grapes on culture plates. Staphylococci are ubiquitous for humans, and many strains compose the normal skin flora. Staphylococcus colonization Colonization Bacteriology 
  • Irritation from bacterial toxins and cell-mediated inflammatory response from antigens
  • Implication of parasitic infestation ( Demodex mites Demodex Mites Rosacea): Treatment of Demodex improves refractory blepharitis Blepharitis Blepharitis is an ocular condition characterized by eyelid inflammation. Anterior blepharitis involves the eyelid skin and eyelashes, while the posterior type affects the meibomian glands. Often, these conditions overlap. Blepharitis but exact role is still unclear.

Etiology^[1‒5]

• 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 diseases:
  • Seborrheic dermatitis Dermatitis Any inflammation of the skin. Atopic Dermatitis (Eczema):
    • Usually causes anterior blepharitis Anterior Blepharitis Blepharitis
    • Honey-colored crusts along the rims of eyelids Eyelids Each of the upper and lower folds of skin which cover the eye when closed. Blepharitis around the eyelashes
  • Rosacea Rosacea Rosacea is a chronic inflammatory disease of the skin that is associated with capillary hyperreactivity. This condition is predominantly seen in middle-aged women, and is more common in fair-skinned patients. Rosacea:
    • Usually causes posterior blepharitis Posterior Blepharitis Blepharitis
    • Inflammatory disorder resulting in flushing and facial redness Redness Inflammation
  • Atopic dermatitis Dermatitis Any inflammation of the skin. Atopic Dermatitis (Eczema):
    • Characterized by scales Scales Dry or greasy masses of keratin that represent thickened stratum corneum. Secondary Skin Lesions along the lash line, 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, and hyperemia 
  • Psoriasis Psoriasis Psoriasis is a common T-cell-mediated inflammatory skin condition. The etiology is unknown, but is thought to be due to genetic inheritance and environmental triggers. There are 4 major subtypes, with the most common form being chronic plaque psoriasis. Psoriasis:
    • Manifests with swollen eyelids Eyelids Each of the upper and lower folds of skin which cover the eye when closed. Blepharitis and crusting of the eyelashes
    • Associated with well-defined plaques with scales Scales Dry or greasy masses of keratin that represent thickened stratum corneum. Secondary Skin Lesions on elbows and knees
• Infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease:
  • Bacterial infection:
    • Staphylococcal dermatitis Dermatitis Any inflammation of the skin. Atopic Dermatitis (Eczema) (most common)
    • Commonly associated with anterior blepharitis Anterior Blepharitis Blepharitis
  • Viral infection:
    • Molluscum contagiosum Molluscum contagiosum Molluscum contagiosum is a viral infection limited to the epidermis and is common in children below 5 years of age. Lesions appear as grouped, flesh-colored, dome-shaped papules with central umbilication. Molluscum Contagiosum
    • Varicella zoster dermatitis Dermatitis Any inflammation of the skin. Atopic Dermatitis (Eczema)
    • Herpes simplex Herpes Simplex A group of acute infections caused by herpes simplex virus type 1 or type 2 that is characterized by the development of one or more small fluid-filled vesicles with a raised erythematous base on the skin or mucous membrane. It occurs as a primary infection or recurs due to a reactivation of a latent infection. Congenital TORCH Infections dermatitis Dermatitis Any inflammation of the skin. Atopic Dermatitis (Eczema)
  • Parasitic infestation:
    • Demodex folliculorum Demodex Folliculorum Infectious Folliculitis (in eyelid follicles): causes anterior blepharitis Anterior Blepharitis Blepharitis 
    • Demodex brevis (in meibomian glands): causes posterior blepharitis Posterior Blepharitis Blepharitis
    • Not all with infestation develop blepharitis Blepharitis Blepharitis is an ocular condition characterized by eyelid inflammation. Anterior blepharitis involves the eyelid skin and eyelashes, while the posterior type affects the meibomian glands. Often, these conditions overlap. Blepharitis
• Others:
  • Irritants and allergens:
    • Swollen, itchy erythematous eyelids Eyelids Each of the upper and lower folds of skin which cover the eye when closed. Blepharitis
    • Improves with removal of offending agent
  • Medications ( retinoids Retinoids Retinol and derivatives of retinol that play an essential role in metabolic functioning of the retina, the growth of and differentiation of epithelial tissue, the growth of bone, reproduction, and the immune response. Dietary vitamin A is derived from a variety of carotenoids found in plants. It is enriched in the liver, egg yolks, and the fat component of dairy products. Fat-soluble Vitamins and their Deficiencies):
    • Causes posterior blepharitis Posterior Blepharitis Blepharitis
    • Improves with discontinuation of medication

Clinical Presentation

Symptoms^[1-5]

• Typically bilateral
• Chronic, episodic red, swollen, itchy eyelids Eyelids Each of the upper and lower folds of skin which cover the eye when closed. Blepharitis
• Gritty or burning sensation
• Watery eyes
• 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 crusting and scaling on the eyelid margin and eyelashes
• Matting of eyelashes in the morning
• Transient blurred vision Blurred Vision Retinal Detachment
• Vesicles Vesicles Female Genitourinary Examination and ulcerations found in herpes or varicella infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease

Signs^[1,4,5]

• Slit-lamp examination Slit-Lamp Examination Blepharitis of posterior blepharitis Posterior Blepharitis Blepharitis:
  • Enlarged meibomian gland Meibomian Gland Chalazion openings
  • Plugged glands with thick, waxy, white or yellow secretions
• Slit-lamp examination Slit-Lamp Examination Blepharitis of anterior blepharitis Anterior Blepharitis Blepharitis:
  • Erythema Erythema Redness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes. Chalazion and 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 of eyelid margin
  • Telangiectasias Telangiectasias Ataxia-telangiectasia on outer eyelid
  • Collarette Collarette Blepharitis: ring-like crust Crust Dried exudate of body fluids (blood, pus, or sebum) on an area of damaged skin Secondary Skin Lesions around eyelashes ( Staphylococcus Staphylococcus Staphylococcus is a medically important genera of Gram-positive, aerobic cocci. These bacteria form clusters resembling grapes on culture plates. Staphylococci are ubiquitous for humans, and many strains compose the normal skin flora. Staphylococcus)
  • Sleeve: cylindrical dandruff Dandruff Excessive shedding of dry scaly material from the scalp in humans. Seborrheic Dermatitis (Demodex infestation)
  • Greasy flakes (seborrheic type)
  • Madarosis Madarosis Blepharitis: loss of lashes
  • Poliosis Poliosis Blepharitis: whitening of lashes
  • Trichiasis Trichiasis A disease of the eye in which the eyelashes abnormally turn inwards toward the eyeball producing constant irritation caused by motion of the lids. Blepharitis: misdirection of lashes
  • Entropion Entropion The turning inward (inversion) of the edge of the eyelid, with the tarsal cartilage turned inward toward the eyeball. Sjögren Syndrome: inward turning of eyelid
  • Ectropion Ectropion The turning outward (eversion) of the edge of the eyelid, resulting in the exposure of the palpebral conjunctiva. Sjögren Syndrome: outward turning of eyelid
• Other findings:
  • Conjunctival injection
  • Tear film stability: tear break-up time < 10 seconds considered abnormal
  • Cornea Cornea The transparent anterior portion of the fibrous coat of the eye consisting of five layers: stratified squamous corneal epithelium; bowman membrane; corneal stroma; descemet membrane; and mesenchymal corneal endothelium. It serves as the first refracting medium of the eye. Eye: Anatomy:
    • Erosions Erosions Corneal Abrasions, Erosion, and Ulcers: from inflamed lid margins 
    • Infiltrates and phlyctenules Phlyctenules Blepharitis (corneal nodules): hypersensitivity reaction to staphylococcal antigens
    • Ulcers
    • Scarring Scarring Inflammation from chronic irritation

Diagnosis

• Clinical, based on the signs and symptoms
• In refractory cases: microscopic examination of the eyelashes to check for Demodex mites Mites Any arthropod of the subclass acari except the ticks. They are minute animals related to the spiders, usually having transparent or semitransparent bodies. They may be parasitic on humans and domestic animals, producing various irritations of the skin (mite infestations). Many mite species are important to human and veterinary medicine as both parasite and vector. Mites also infest plants. Scabies helps if with typical presentation (sleeves on eyelashes)
• Cultures may be indicated for recurrent anterior blepharitis Anterior Blepharitis Blepharitis.^[6]
• Consider eyelid tumors in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with atypical eyelid-margin 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 that is not responsive to medical therapy.^[6]

Differential Diagnosis

• Conjunctivitis Conjunctivitis Conjunctivitis is a common inflammation of the bulbar and/or palpebral conjunctiva. It can be classified into infectious (mostly viral) and noninfectious conjunctivitis, which includes allergic causes. Patients commonly present with red eyes, increased tearing, burning, foreign body sensation, and photophobia. Conjunctivitis: 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 of the conjunctiva Conjunctiva The mucous membrane that covers the posterior surface of the eyelids and the anterior pericorneal surface of the eyeball. Eye: Anatomy, the outer lining of the eye. Etiology can be infectious or non-infectious. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with redness Redness Inflammation and discharge on one or both eyes Both Eyes Refractive Errors. Bacterial conjunctivitis Bacterial Conjunctivitis Conjunctivitis often has purulent discharge Purulent Discharge Dacryocystitis whereas viral causes have watery discharge.
• Dacryocystitis Dacryocystitis Dacryocystitis is inflammation of the lacrimal sac due to nasolacrimal duct obstruction and the subsequent stasis of tears. The condition can have an acute or chronic onset. Acute dacryocystitis presents within hours or days with redness, swelling, tenderness, and excessive tearing. Dacryocystitis: 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 of the nasolacrimal sac commonly caused by duct obstruction. The condition presents as redness Redness Inflammation and swelling Swelling Inflammation in the area of the tear duct. Tear stasis facilitates bacterial overgrowth Bacterial overgrowth Lactose Intolerance and infection occurs, manifesting as mucopurulent discharge. For management, warm compresses Warm Compresses Chalazion are applied and antibiotics are given if indicated. For persistent obstruction, nasolacrimal duct Nasolacrimal Duct Nasolacrimal duct. Dacryocystitis intubation Intubation Peritonsillar Abscess and other surgical interventions are treatment options.
• Hordeolum Hordeolum A hordeolum is an acute infection affecting the meibomian, Zeiss, or Moll glands of the eyelid. Stasis of the gland secretions predisposes to bacterial infection. Staphylococcus aureus is the most common pathogen. Hordeolum (Stye) ( stye Stye A hordeolum is an acute infection affecting the meibomian, Zeiss, or Moll glands of the eyelid. Stasis of the gland secretions predisposes to bacterial infection. Staphylococcus aureus is the most common pathogen. Hordeolum (Stye)): an abscess Abscess Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection. Chronic Granulomatous Disease affecting the eyelash follicle or eyelid gland. The condition usually presents as a locally painful, erythematous, swollen eyelid margin. Most lesions resolve spontaneously, but gentle warm compresses Warm Compresses Chalazion facilitate drainage. If the abscess Abscess Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection. Chronic Granulomatous Disease does not resolve, incision and drainage Incision And Drainage Chalazion by an ophthalmologist are performed.
• Chalazion Chalazion A chalazion is one of the most common inflammatory lesions of the eyelid. It is caused by obstruction of the Meibomian or Zeis glands, leading to granulomatous inflammation and resulting in a firm, rubbery, slow-growing nodule that is typically non-tender. Chalazion: a firm, nontender mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast at the eyelid resulting from obstruction of the Zeis or meibomian glands. The condition is usually managed conservatively with warm compresses Warm Compresses Chalazion. Persistence of the lesion requires incision and curettage Curettage A scraping, usually of the interior of a cavity or tract, for removal of new growth or other abnormal tissue, or to obtain material for tissue diagnosis. It is performed with a curet (curette), a spoon-shaped instrument designed for that purpose. Benign Bone Tumors or glucocorticoid injection by an ophthalmologist.