Differential Diagnosis for a 4-year-old with a Viral Infection
Single most likely diagnosis
- Kawasaki Disease: This condition is characterized by a fever that lasts for more than five days, along with other symptoms such as rash, swollen lymph nodes, and in some cases, drooping eyelids due to facial weakness. The rash can appear on the face and other parts of the body, and the disease often resolves on its own within a week, fitting the "comes and goes" description.
Other Likely diagnoses
- Fifth Disease (Erythema Infectiosum): Caused by parvovirus B19, this illness is common in children and presents with a distinctive "slapped-cheek" rash on the face, which could be accompanied by a low-grade fever and general malaise. The rash may not appear on the back initially but can spread.
- Roseola: A viral infection that causes a high fever followed by a rash once the fever breaks. The rash can appear on the face and trunk, and while it typically doesn't cause droopy eyes, the fever and rash pattern could fit the description.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Meningitis: Although less likely given the rash and specific pattern of illness, meningitis can present with fever, rash (in the case of meningococcal meningitis), and signs of increased intracranial pressure, such as drooping eyelids due to cranial nerve involvement. It's a medical emergency requiring immediate attention.
- Encephalitis: Inflammation of the brain, usually caused by viral infections, can lead to symptoms like fever, rash (depending on the causative agent), and neurological signs such as drooping eyelids. Prompt diagnosis and treatment are crucial.
Rare diagnoses
- Hand, Foot, and Mouth Disease (HFMD): While HFMD typically causes sores in the mouth and a rash on the hands and feet, some variants can cause a rash on the face. It's less likely to cause droopy eyes but is a consideration in the differential for viral rashes in children.
- Scarlet Fever: Caused by group A Streptococcus, this illness presents with a rash, fever, and "strawberry tongue." The rash can appear on the face and may be accompanied by other symptoms, though droopy eyes are not typical.