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Introduction to Conjunctival Diseases

Overview of the Class

• The session focuses on conjunctival diseases, emphasizing their importance in ophthalmology. Students are encouraged to ask questions throughout the lecture for clarity and understanding.

Understanding Conjunctivitis

• Conjunctivitis refers to inflammation of the conjunctiva, which can stem from various causes beyond just infection. It is crucial to recognize that "conjunctivitis" is a broad term similar to saying "rash" in dermatology.

Anatomy of the Conjunctiva

• The conjunctiva covers the sclera (the white part of the eye) and lines the inner eyelid, appearing as a pale pink mucosa when healthy. This structure plays a vital role in distributing tears during blinking, maintaining ocular health.

Types of Conjunctivitis

Classification of Conjunctivitis

• There are three primary types of conjunctivitis: bacterial, viral, and allergic. Understanding these distinctions is essential for diagnosis and treatment strategies. These classifications often appear in examinations.

Bacterial Conjunctivitis

• Bacterial conjunctivitis can affect individuals regardless of age or gender; transmission typically occurs through direct contact (e.g., touching eyes with contaminated hands). Common pathogens include Staphylococcus aureus and Streptococcus pneumoniae among others.

Mechanisms of Infection

• Infections may arise from an imbalance in normal flora or retrograde movement from lacrimal ducts due to conditions like dacryocystitis, leading to bacterial proliferation on the conjunctiva's surface. Additionally, exposure to contaminated substances can also cause infection.

Clinical Presentation

Symptoms and Signs

• Patients with bacterial conjunctivitis often present with:

• Redness in the eye.

• A sensation of a foreign body.

• Tearing.

• Greenish-yellow purulent discharge that accumulates overnight due to reduced blinking while sleeping.

These symptoms indicate irritation but are not specific enough for definitive diagnosis without further examination.

Key Diagnostic Indicators

• Important diagnostic clues include:

• The presence of purulent discharge suggests a bacterial origin.

• Vascularization patterns may show peripheral rather than central involvement.

Understanding these signs helps differentiate between types of conjunctival infections effectively.

Pathophysiology and Treatment Considerations

Irritation Mechanisms

• The cornea has numerous sensory nerve endings; thus any irritation—whether from secretions or environmental factors—can lead patients to feel discomfort akin to having something lodged in their eye even if there isn't an actual foreign body present. This highlights how symptoms can be misleading without proper assessment by healthcare professionals.

Treatment Approaches

• Treatment varies based on causative agents; however, recognizing key symptoms such as purulent discharge aids clinicians in determining appropriate therapeutic interventions tailored specifically for bacterial infections versus other forms like viral or allergic conjunctivitis. Understanding this distinction is critical for effective management strategies moving forward into clinical practice settings.

Bacterial Resistance and Conjunctivitis

Overview of Bacterial Resistance

• Discussion on bacterial resistance, specifically mentioning gentamicin, tobramycin, neomycin, polymyxins, and tetracyclines. Emphasis on the importance of not using tetracyclines in children.

Quinolones and Complications

• Introduction of quinolones such as norfloxacin, moxifloxacin, and gatifloxacin. Mention of complications including chronicity tendencies and blepharoconjunctivitis due to certain bacteria's ability to colonize eyelid margins.

Staphylococcus Aureus in Conjunctivitis

• Highlighting Staphylococcus aureus as a significant cause of conjunctivitis and blepharoconjunctivitis, accounting for over 50% of cases. Clinical signs include redness and discharge from both conjunctiva and eyelids.

Chlamydia-Induced Conjunctivitis

• Explanation that chlamydia is a sexually transmitted infection (STI), with inclusion conjunctivitis being associated with serotypes D and K. Importance noted for exam preparation regarding this topic.

Tracoma: A Chronic Condition

• Description of trachoma caused by chlamydia subtypes A, B, C; linked to poor hygiene conditions. The potential for chronicity leading to blindness is emphasized alongside its historical prevalence in specific communities.

Clinical Presentation of Inclusion Conjunctivitis

• Clinical presentation includes sudden onset red eye typically unilateral; often affects the right eye due to dominant hand usage among right-handed individuals.

Diagnosis and Treatment Protocols

• Diagnosis involves PCR testing for Chlamydia trachomatis in inclusion conjunctivitis cases. Treatment options include tetracyclines or erythromycin for both the infected individual and their sexual partner.

Hygiene Practices in Eye Care

• Stress on the necessity of handwashing before examining patients' eyes to prevent cross-contamination with infections like chlamydia or herpes simplex virus. Awareness raised about unconscious touching of eyes throughout the day.

Understanding Trachoma and Conjunctivitis

Trachoma Overview

• Trachoma is the most common cause of blindness in underdeveloped countries, characterized by changes in the tarsal conjunctiva.

• The conjunctiva appears hyperemic with fibrosis, likely due to chlamydia infections leading to continuous corneal erosion and potential blindness.

Pathophysiology of Eyelid Inversion

• Eyelid inversion (entropion) causes eyelashes to contact the cornea, perpetuating ulcers that can lead to a white, scarred cornea.

Gonococcal Conjunctivitis

• Gonococcal conjunctivitis manifests 2-4 days post-infection with purulent yellow discharge from intense conjunctival inflammation and stromal necrosis.

• Neisseria gonorrhoeae can perforate the cornea without prior epithelial damage, making it particularly aggressive compared to skin infections.

Risks Associated with Contact Lenses

• Patients using contact lenses are at higher risk for ulceration if there is an epithelial defect; protective measures are crucial during procedures involving eye exposure.

Diagnosis and Treatment of Gonococcal Conjunctivitis

• Characteristic preauricular adenopathy is noted; diagnosis involves culturing for diplococcus bacteria. Treatment typically includes penicillin.

Viral Conjunctivitis: Types and Symptoms

Viral vs. Bacterial Conjunctivitis

• Viral conjunctivitis is less frequent than bacterial types and can be categorized into those associated with systemic exanthematous diseases or primarily affecting the eye.

Transmission Mechanisms

• Transmission occurs through direct contact with saliva or respiratory secretions, similar to COVID transmission via sneezing.

Clinical Presentation of Viral Conjunctivitis

• Symptoms include red eyes, foreign body sensation, and abundant tearing; however, secretion tends to be scanty and more serous rather than purulent.

Specific Viruses Causing Conjunctivitis

• Adenovirus is the most common viral agent causing significant edema in lower fornices along with lymphadenopathy in preauricular and submandibular regions.

Management Strategies for Viral Conjunctivitis

Resolution Timeline

• The typical resolution time for viral conjunctivitis symptoms is approximately two weeks; treatment focuses on symptom management rather than antibiotics since it's viral.

Key Takeaways

Infiltrados Nuulares y Conjuntivitis Alérgicas

Infiltrados Nuulares

• Se presentan infiltrados nuulares en la córnea, que son manchas visibles causadas por inflamación en el estroma ocular.

• Si no se tratan a tiempo, estas manchas pueden dejar cicatrices permanentes que afectan la visión. Es crucial tratar estas conjuntivitis agresivas.

• Los pacientes suelen tocarse los ojos debido a la comezón, lo que puede propagar la infección de un ojo al otro.

Tipos de Conjuntivitis Alérgicas

• La conjuntivitis alérgica es provocada por alergias y se manifiesta cuando un alérgeno afecta una mucosa previamente sensibilizada.

• Comúnmente observada en personas que usan serums para pestañas, causando irritación y edema en los párpados.

Características Clínicas

• En la conjuntivitis primaveral, hay inflamación crónica con papilas visibles; esto indica una reacción alérgica dentro del ojo.

• Los síntomas incluyen prurito intenso, fotofobia (sensibilidad a la luz), lagrimeo y secreción filamentosa.

Diferenciación de Síntomas

• La secreción en conjuntivitis alérgicas no es espesa ni verdosa como en las bacterianas; es más ligera y menos intensa.

• La conjuntivitis por fiebre puede presentarse unilateral o bilateral con síntomas moderados de lagrimeo y prurito.

Tratamiento y Manejo

• El tratamiento incluye antihistamínicos como ketotifeno y olopatadina, estabilizadores de mastocitos, además de compresas frías para aliviar los síntomas.

• En casos severos o dermatitis asociada, se recomienda suspender productos irritantes aplicados sobre el área afectada.

Signo Denny Morgan