Differential Diagnosis for Fever with Rash and Hepatosplenomegaly in Pediatrics
Single Most Likely Diagnosis
- Infectious Mononucleosis (Mono): Caused by Epstein-Barr virus (EBV), it is a common condition in pediatrics that presents with fever, rash, and hepatosplenomegaly. The rash can appear after the administration of ampicillin, which is a classic clue.
Other Likely Diagnoses
- Juvenile Idiopathic Arthritis (JIA): Systemic JIA can present with fever, rash, and hepatosplenomegaly, especially in the early stages. The rash is often evanescent and can be accompanied by lymphadenopathy.
- Kawasaki Disease: An acute febrile illness that includes rash, lymphadenopathy, and can have hepatosplenomegaly. It's a leading cause of acquired heart disease in children.
- Infectious Diseases (e.g., Toxoplasmosis, Cytomegalovirus): These infections can cause fever, rash, and hepatosplenomegaly, particularly in immunocompromised children or congenitally infected newborns.
Do Not Miss Diagnoses
- Meningococcemia: A severe bacterial infection that can cause fever, rash (petechial or purpuric), and can lead to hepatosplenomegaly due to disseminated intravascular coagulation. It's life-threatening and requires immediate treatment.
- Leukemia/Lymphoma: Although less common, these malignancies can present with systemic symptoms including fever, rash, and hepatosplenomegaly due to infiltration of the liver and spleen by malignant cells.
- Systemic Lupus Erythematosus (SLE): A chronic autoimmune disease that can cause a wide range of symptoms including fever, rash, and hepatosplenomegaly. It's crucial to diagnose early to prevent long-term organ damage.
Rare Diagnoses
- Langerhans Cell Histiocytosis (LCH): A rare disorder that can cause fever, rash, and hepatosplenomegaly due to the proliferation of Langerhans cells in various organs.
- Hemophagocytic Lymphohistiocytosis (HLH): A rare and life-threatening condition of the immune system where it produces too many activated immune cells called macrophages and lymphocytes. It can cause fever, rash, and hepatosplenomegaly.
- Babesiosis: A rare disease caused by infection with Babesia, a group of microscopic parasites that infect red blood cells. It can cause fever, rash, and hepatosplenomegaly, especially in asplenic or immunocompromised patients.