Differential Diagnosis for Neonatal Conjunctivitis versus Blocked Tear Duct in a 17-Day-Old Child

Single Most Likely Diagnosis

• Neonatal conjunctivitis (Chemical or Infectious): This is the most likely diagnosis given the age of the child and the common presentation of conjunctivitis in the neonatal period, which can be caused by chemical irritation from prophylactic eye drops or infectious agents such as bacteria, viruses, or chlamydia.

Other Likely Diagnoses

• Blocked tear duct (Nasolacrimal duct obstruction): This condition is common in newborns and can cause excessive tearing and discharge, which might be mistaken for conjunctivitis. It usually resolves on its own but can sometimes require intervention.
• Gonococcal or Chlamydial conjunctivitis: These are specific types of infectious conjunctivitis that can be transmitted from the mother to the child during birth and require prompt treatment to prevent serious complications.

Do Not Miss Diagnoses

• Herpes Simplex Virus (HSV) conjunctivitis: Although less common, HSV conjunctivitis can lead to serious complications, including corneal ulcers and potential blindness if not treated promptly.
• Gonococcal conjunctivitis with potential for systemic infection: Gonococcal infection can disseminate and cause life-threatening conditions if not recognized and treated early.

Rare Diagnoses

• Congenital glaucoma: This condition can present with tearing, redness, and sensitivity to light, which might be confused with conjunctivitis or a blocked tear duct. It requires urgent ophthalmological evaluation to prevent vision loss.
• Dacryocystitis: An infection of the lacrimal sac, which can occur in association with a blocked tear duct and requires antibiotic treatment to prevent further complications.

Each of these diagnoses has distinct implications for treatment and prognosis, emphasizing the importance of a thorough evaluation to determine the underlying cause of the symptoms in a 17-day-old child.