Differences Between Complete Blood Count in Enteric Fever and Viral Fever

Enteric Fever CBC Findings

In enteric fever, the complete blood count typically shows leukopenia with relative lymphocytosis, while viral fevers generally present with normal to low white blood cell counts with lymphocytic predominance, according to the Clinical Infectious Diseases journal 1
Monocyte count often shows monocyte predominance, which may suggest the presence of an intracellular pathogen such as Salmonella, as reported in the Clinical Infectious Diseases journal 1
Platelet count may be decreased (thrombocytopenia) in enteric fever, as noted in the Clinical Infectious Diseases journal 1

White blood cell count is usually normal to low (leukopenia) in viral fever, as reported in the Clinical Infectious Diseases journal 1
Differential count typically shows lymphocytic predominance in viral fever, according to the Clinical Infectious Diseases journal 1
Eosinophil count is generally normal in viral fever, as noted in the Clinical Infectious Diseases journal 1

CBC alone is insufficient for diagnosis of enteric fever due to its non-specific nature, as stated in the Clinical Infectious Diseases journal 2, 3
Blood culture remains the gold standard diagnostic test with approximately 50% sensitivity for enteric fever, as reported in the Clinical Infectious Diseases journal 2, 4
Bone marrow culture has higher sensitivity for enteric fever diagnosis, particularly valuable if antimicrobial agents have been administered, according to the Clinical Infectious Diseases journal and the Journal of Infection 2, 5
Additional cultures of stool, duodenal fluid, and urine may be beneficial for enteric fever diagnosis, as noted in the Clinical Infectious Diseases journal 2
Serologic tests should not be used for enteric fever diagnosis due to poor performance characteristics, as stated in the Clinical Infectious Diseases journal and the Journal of Infection 2, 6
Molecular diagnostic tests are more reliable for specific viral diagnosis, as reported in the Clinical Infectious Diseases journal 7

Monocytosis is more suggestive of enteric fever than viral infection, according to the Clinical Infectious Diseases journal 1
Persistent fever with relative bradycardia and normal to low WBC count should raise suspicion for enteric fever in returning travelers from endemic areas, as noted in the Journal of Infection 5, 6