Differential Diagnosis for a 5-month-old boy with fever and irritability
- Single most likely diagnosis
- Acute otitis media (AOM): The patient's symptoms of fever, irritability, and erythematous, bulging tympanic membranes bilaterally are consistent with AOM, a common condition in infants.
- Other Likely diagnoses
- Viral upper respiratory tract infection (URTI): The presence of clear rhinorrhea and the patient's age make a viral URTI a likely diagnosis, which may be contributing to the patient's symptoms.
- Viral gastroenteritis: Although the patient is still producing an adequate number of wet diapers, a viral gastroenteritis could cause fever, irritability, and decreased interest in feeding.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Bacterial meningitis: Although the patient is consolable and has no obvious signs of meningismus, bacterial meningitis is a life-threatening condition that requires prompt diagnosis and treatment.
- Sepsis: The patient's fever, tachycardia, and irritability could be signs of sepsis, which is a medical emergency.
- Urinary tract infection (UTI): A UTI could cause fever and irritability in an infant, and is an important diagnosis to consider, especially if the patient has a fever without an obvious source.
- Rare diagnoses
- Osteomyelitis or septic arthritis: These conditions could cause fever and irritability in an infant, but are less common and would typically be associated with more specific signs and symptoms, such as swelling or tenderness of a joint or bone.
- Infant botulism: This rare condition could cause weakness, irritability, and feeding difficulties in an infant, but is relatively rare and would typically be associated with more specific signs and symptoms, such as weakness or paralysis.