What is the diagnosis for a 2-year-old presenting with low-grade fever, rhinorrhea (runny nose), nasal congestion, anorexia (loss of appetite), insomnia (trouble sleeping), bilateral conjunctivitis (red eyes), and a maculopapular rash on the cheeks and nose, with clear lung sounds, for one week?

Differential Diagnosis for a 2-year-old with Low-grade Fevers, Runny Nose, Congestion, and Bilateral Red Eyes

• Single most likely diagnosis:
  • Viral upper respiratory tract infection (URTI): This is the most likely diagnosis given the symptoms of low-grade fevers, runny nose, congestion, and bilateral red eyes, which are common in viral URTIs. The presence of a small rash on the cheek and nose area could be indicative of a viral exanthem.
• Other Likely diagnoses:
  • Allergic rhinitis: Although less likely given the fever and rash, allergic rhinitis could explain the runny nose, congestion, and red eyes, especially if the child has a history of allergies.
  • Adenoviral conjunctivitis: This condition could explain the bilateral red eyes and is often accompanied by upper respiratory symptoms.
  • Roseola: This viral illness is characterized by high fever, followed by a rash, but it's possible that the fever was not high-grade in this case.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
  • Bacterial conjunctivitis: Although less likely, bacterial conjunctivitis can lead to serious complications if left untreated, such as corneal ulcers or perforation.
  • Kawasaki disease: This condition is characterized by fever, rash, conjunctivitis, and cervical lymphadenopathy, and can lead to coronary artery aneurysms if not treated promptly.
  • Orbital cellulitis: This is a serious infection that can cause redness, swelling, and pain around the eye, and can lead to vision loss or intracranial complications if not treated promptly.
• Rare diagnoses:
  • Scarlet fever: This condition is characterized by a rash, fever, and strawberry tongue, and is caused by group A streptococcal infection.
  • Erythema infectiosum (Fifth disease): This viral illness is characterized by a distinctive "slapped-cheek" rash and can cause fever, runny nose, and conjunctivitis.
  • Leptospirosis: This bacterial infection can cause fever, conjunctivitis, and rash, but is relatively rare in children and usually associated with exposure to contaminated water or soil.