Differential Diagnosis for a 4-year-old with High Fever, Rashes, Runny Nose, and Mild Cough
- Single most likely diagnosis:
- Roseola infantum: This is a common illness in young children characterized by high fever followed by a rash. The symptoms match closely, including the age of the patient, duration of fever, and the appearance of the rash after the fever.
- Other Likely diagnoses:
- Fifth disease (Erythema infectiosum): Caused by parvovirus B19, it presents with a distinctive "slapped cheek" appearance, followed by a lacy rash on the body. While the rash description doesn't perfectly match, the age and other symptoms could align.
- Measles: Although less common in areas with high vaccination rates, measles can present with fever, cough, runny nose, and a rash. The rash in measles typically starts on the face and spreads downward.
- Rubella (German measles): Similar to measles, it presents with fever, rash, and upper respiratory symptoms. The rash can appear as small, flat spots.
- Do Not Miss diagnoses:
- Meningococcemia: A severe infection caused by Neisseria meningitidis, which can present with fever, rash, and upper respiratory symptoms. The rash can be petechial or purpuric and is a medical emergency.
- Kawasaki disease: An acute febrile illness of childhood that can lead to coronary artery aneurysms if not treated promptly. It is characterized by fever, rash, conjunctivitis, cervical lymphadenopathy, and changes in the lips and oral cavity.
- Rare diagnoses:
- Enteroviral infections (e.g., Hand, Foot, and Mouth Disease): While more commonly associated with vesicular lesions on the hands and feet, some enteroviral infections can cause a variety of rashes and systemic symptoms.
- Scarlet fever: Caused by group A beta-hemolytic streptococci, it presents with a distinctive sandpapery rash, fever, and "strawberry tongue." The rash typically starts on the chest and spreads.