Lymphocyte-white blood cell count ratio: a quickly available screening tool to differentiate acute purulent tonsillitis from glandular fever.

OBJECTIVE

To find a quickly available screening tool for the differentiation of patients with glandular fever from those with acute purulent tonsillitis. The null hypothesis was that there was no difference between the lymphocyte-white blood cell count (L/WCC) ratio between the 2 patient groups.

DESIGN

Retrospective pilot study based on laboratory tests for lymphocyte counts, white blood cell counts, and the mononucleosis spot test.

SETTING

Ear, Nose, and Throat Department, St George's Hospital, London, England.

PATIENTS: One hundred twenty patients with glandular fever and 100 patients with bacterial tonsillitis.

MAIN OUTCOME MEASURES: Results from the mononucleosis spot test in conjunction with the clinical picture and the L/WCC ratio were analyzed. Significant differences were evaluated using the Mann-Whitney test and Fisher exact test.

RESULTS

The L/WCC ratio was significantly different in the 2 groups (P<.001). The mean L/WCC ratio in the glandular fever group was 0.54 and the mean L/WCC ratio in the bacterial tonsillitis group was 0.10. A ratio higher than 0.35 had a specificity of 100% and a sensitivity of 90% for the detection of glandular fever.

CONCLUSIONS

We recommend that the L/WCC ratio should be used as an indicator to decide whether mononucleosis spot tests should be requested. A ratio higher than 0.35 had a high specificity in our study group.