OBJECTIVE: To determine whether the toxic neutrophil count (TNC), defined as the sum of the number of peripheral blood neutrophils with vacuoles plus the number with toxic granulations per 100 neutrophils examined, can be used as an aid to early diagnosis of Kawasaki disease (KD). METHODS: Prospective evaluation at a tertiary care pediatric hospital of 56 acutely febrile children with at least one other clinical criterion for KD. Clinical characteristics and TNC were compared for 3 groups of patients: those with (1) definite KD, (2) probable KD, and (3) unlikely KD. The sensitivity and specificity of the TNC at various cutoff points was determined. RESULTS: We evaluated 56 patients (Group 1, N=27; Group 2, N=4; Group 3, N=25). Mean TNC (TNC/mm3) were higher in the patients with definite KD compared to patients with unlikely KD (38 vs 24; p=0.037). At a TNC cutoff of > or =70, the test had a specificity of 100%, but a sensitivity of only 18%. The likelihood ratio (the number of times more likely this TNC result is to be found in KD versus non-KD subjects) was 8.89. At a cutoff of > or =10, the test had a high sensitivity of 92% and specificity of 38%. CONCLUSION: No laboratory test replaced the need for careful clinical evaluation in cases of suspected KD. The TNC may be a useful adjunct to the clinical assessment of children with KD, particularly at the extremes of measurement.
OBJECTIVE: To determine whether the toxic neutrophil count (TNC), defined as the sum of the number of peripheral blood neutrophils with vacuoles plus the number with toxic granulations per 100 neutrophils examined, can be used as an aid to early diagnosis of Kawasaki disease (KD). METHODS: Prospective evaluation at a tertiary care pediatric hospital of 56 acutely febrile children with at least one other clinical criterion for KD. Clinical characteristics and TNC were compared for 3 groups of patients: those with (1) definite KD, (2) probable KD, and (3) unlikely KD. The sensitivity and specificity of the TNC at various cutoff points was determined. RESULTS: We evaluated 56 patients (Group 1, N=27; Group 2, N=4; Group 3, N=25). Mean TNC (TNC/mm3) were higher in the patients with definite KD compared to patients with unlikely KD (38 vs 24; p=0.037). At a TNC cutoff of > or =70, the test had a specificity of 100%, but a sensitivity of only 18%. The likelihood ratio (the number of times more likely this TNC result is to be found in KD versus non-KD subjects) was 8.89. At a cutoff of > or =10, the test had a high sensitivity of 92% and specificity of 38%. CONCLUSION: No laboratory test replaced the need for careful clinical evaluation in cases of suspected KD. The TNC may be a useful adjunct to the clinical assessment of children with KD, particularly at the extremes of measurement.
Authors: Amanda Costa Ayres Salmeron; Wallace Pitanga Bezerra; Rafaela Lúcia Lopes de Souza; Luanderson Cardoso Pereira; Lícia Maria do Nascimento; Anna Cláudia Calvielli Castelo Branco; Luiza Emilia Cavalcanti Simas; Valéria Azevedo de Almeida; Pedro Henrique de Souza Palmeira; Christiane Medeiros Bezerra; Paulo Marcos Matta Guedes; Maria Notomi Sato; Valéria Soraya de Farias Sales; Reginaldo Antônio de Oliveira Freitas Júnior; Tatjana de Souza Lima Keesen; Manuela Sales Lima Nascimento Journal: Med Microbiol Immunol Date: 2022-07-20 Impact factor: 4.148