TY - JOUR
T1 - Diagnostic value of cell bound and circulating neutrophil antibody detection in pediatric neutropenia
AU - Porretti, Laura
AU - Farruggia, Piero
AU - Colombo, Federico Simone
AU - Cattaneo, Alessandra
AU - Ghilardi, Roberta
AU - Mirra, Nadia
AU - Notarangelo, Lucia Dora
AU - Martire, Baldassarre
AU - Trombetta, Elena
AU - Milani, Silvano
AU - Vener, Claudia
AU - Rebulla, Paolo
PY - 2018/4/1
Y1 - 2018/4/1
N2 - Background: Chronic benign neutropenia of infancy includes primary autoimmune neutropenia (pAIN) and chronic idiopathic neutropenia (CIN). A diagnosis of CIN is supported by the absence of free and/or cell-bound neutrophil autoantibodies, which can be detected by flow cytometry with the indirect-granulocyte immunofluorescence test (I-GIFT) and direct-granulocyte immunofluorescence test (D-GIFT), respectively. Conclusive evidence is lacking on the diagnostic value of the D-GIFT, whose performance requires specific laboratory expertise, may be logistically difficult, and hampered by very low neutrophil count in patient samples. This study investigated whether the evaluation of D-GIFT improves the diagnostic accuracy of pediatric neutropenia. Procedure: I-GIFT and D-GIFT were performed in 174 pAIN, 162 CIN, 81 secondary AIN, 51 postinfection neutropenic, and 65 nonautoimmune neutropenic children referred to this laboratory during 2002–2014. Results: Using 90% specific median fluorescence intensity cut-off values calculated by receiver operating characteristic curves, D-GIFT was positive in 49% of CIN patients, who showed similar clinical features as those with pAIN. In 44 (27%) of 162 CIN patients, I-GIFT was repeated two to three times in a year, resulting positive in 12 and two patients at second and third screening, respectively. Interestingly, 10 of the latter 14 patients showed a positive D-GIFT at the first serological screening. False positive D-GIFT was shown by 12% and 22% of nonneutropenic and nonautoimmune neutropenic patients, respectively. Conclusions: D-GIFT evaluation improves the diagnostic accuracy of pediatric neutropenia, but improvement of cell-bound antibody detection is needed to decrease false positive results.
AB - Background: Chronic benign neutropenia of infancy includes primary autoimmune neutropenia (pAIN) and chronic idiopathic neutropenia (CIN). A diagnosis of CIN is supported by the absence of free and/or cell-bound neutrophil autoantibodies, which can be detected by flow cytometry with the indirect-granulocyte immunofluorescence test (I-GIFT) and direct-granulocyte immunofluorescence test (D-GIFT), respectively. Conclusive evidence is lacking on the diagnostic value of the D-GIFT, whose performance requires specific laboratory expertise, may be logistically difficult, and hampered by very low neutrophil count in patient samples. This study investigated whether the evaluation of D-GIFT improves the diagnostic accuracy of pediatric neutropenia. Procedure: I-GIFT and D-GIFT were performed in 174 pAIN, 162 CIN, 81 secondary AIN, 51 postinfection neutropenic, and 65 nonautoimmune neutropenic children referred to this laboratory during 2002–2014. Results: Using 90% specific median fluorescence intensity cut-off values calculated by receiver operating characteristic curves, D-GIFT was positive in 49% of CIN patients, who showed similar clinical features as those with pAIN. In 44 (27%) of 162 CIN patients, I-GIFT was repeated two to three times in a year, resulting positive in 12 and two patients at second and third screening, respectively. Interestingly, 10 of the latter 14 patients showed a positive D-GIFT at the first serological screening. False positive D-GIFT was shown by 12% and 22% of nonneutropenic and nonautoimmune neutropenic patients, respectively. Conclusions: D-GIFT evaluation improves the diagnostic accuracy of pediatric neutropenia, but improvement of cell-bound antibody detection is needed to decrease false positive results.
KW - children
KW - neutropenia
KW - neutrophil antibodies
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U2 - 10.1002/pbc.26904
DO - 10.1002/pbc.26904
M3 - Article
AN - SCOPUS:85042272332
VL - 65
JO - Pediatric Blood and Cancer
JF - Pediatric Blood and Cancer
SN - 1545-5009
IS - 4
M1 - e26904
ER -