Differential Diagnosis for Neonatal Conjunctivitis

Single Most Likely Diagnosis

• Chemical Conjunctivitis: This is the most common cause of neonatal conjunctivitis, occurring due to the instillation of silver nitrate or other antimicrobial prophylaxis at birth. It typically presents within the first 24-48 hours of life.

Other Likely Diagnoses

• Gonococcal Conjunctivitis: Caused by Neisseria gonorrhoeae, this condition is a significant concern due to its potential for severe consequences, including corneal perforation. It usually presents within the first 5 days of life.
• Chlamydial Conjunctivitis: Caused by Chlamydia trachomatis, this is another common infectious cause of neonatal conjunctivitis, typically presenting between 5-14 days of life.
• Viral Conjunctivitis: Herpes simplex virus (HSV) and other viruses can cause neonatal conjunctivitis, often presenting with other systemic symptoms.

Do Not Miss Diagnoses

• Herpes Simplex Virus (HSV) Keratoconjunctivitis: Although less common, HSV infection can lead to severe ocular and systemic disease. Early recognition and treatment are crucial to prevent long-term sequelae.
• Neonatal Inclusion Conjunctivitis due to Chlamydia: While not immediately life-threatening, missing this diagnosis can lead to prolonged infection and potential long-term consequences if not adequately treated.

Rare Diagnoses

• Congenital Dacryocystitis: Infection of the nasolacrimal duct, which can cause conjunctivitis due to obstruction and secondary infection.
• Bacterial Conjunctivitis due to other pathogens: Such as Pseudomonas aeruginosa, Haemophilus influenzae, or Streptococcus pneumoniae, which are less common causes but should be considered in the appropriate clinical context.
• Fungal Conjunctivitis: Extremely rare in neonates but could be considered in cases where conventional bacterial and viral causes have been ruled out, especially in immunocompromised infants.

Treatment for Neonatal Conjunctivitis

The treatment depends on the suspected or confirmed cause:

• Chemical Conjunctivitis: Typically resolves without specific treatment other than supportive care (e.g., saline irrigation).
• Gonococcal Conjunctivitis: Requires immediate treatment with intravenous or intramuscular antibiotics (e.g., ceftriaxone) and may necessitate hospitalization.
• Chlamydial Conjunctivitis: Treated with oral erythromycin or azithromycin for the infant, and the mother and her sexual partners should also be evaluated and treated.
• Viral Conjunctivitis: Antiviral medication (e.g., acyclovir) for HSV; supportive care for other viruses.
• Herpes Simplex Virus (HSV) Keratoconjunctivitis: Requires antiviral therapy (e.g., acyclovir) and often necessitates consultation with an ophthalmologist.

It's crucial to consult with an ophthalmologist or a pediatrician for the diagnosis and management of neonatal conjunctivitis, as the treatment and prognosis can vary significantly depending on the underlying cause.