Autoimmune neutropenia in children: analysis of 116 cases

To cite this article: Audrain M, Martin J, Fromont P, Prié N, Thomas C, Muller J‐Y. Autoimmune neutropenia in children: analysis of 116 cases. Pediatr Allergy Immunol 2011; 22 : 494–496. Diagnosis of autoimmune neutropenia (AIN) in infants is important, because it allows the exclusion of more severe forms of neutropenia that have an increased risk for leukemia. AIN is characterized by chronic neutropenia, which spontaneously resolves within several months to a few years, and mild infections. Diagnosis is confirmed by the presence of antibodies directed against neutrophil antigens. The human neutrophil antigen (HNA) system is a polymorphic system, which includes five antigen groups with different polymorphisms. In AIN, antibodies are mostly directed against HNA‐1 (or against a specific allele of HNA‐1) and HNA‐4. Here, we present a series of 116 infants with AIN. We observed that anti‐neutrophil antibodies were present in 60% cases; directed against HNA‐1a in 73% of cases. In addition, we showed there was a bias in the HNA allele distribution in these infants because the frequency of the HNA‐1a allele was greater in comparison with controls.     

Alloimmune neonatal neutropenia and thrombocytopenia associated with maternal anti HNA-1a, HPA-3b and HLA antibodies.

The incidence of alloimmune neonatal neutropenia combined with neonatal alloimmune thrombocytopenia is very low. We report a case of a neonate who suffered severe neutropenia and thombocytopenia with widespread petechial spots. The presence of alloantibodies in mother's and patient's sera was analyzed by lymphocytotoxicity test, agglutination test, granulocyte indirect immunofluorescence test, platelet immunofluorescence test (PIFT) and solid phase enzyme-linked immunosorbent assay. Human neutrophil antigens (HNA) and human platelet antigen (HPA) genotypes were tested by polymerase chain reaction analyses. The mother's and patient's sera reacted with neutrophils and lymphocytes of the father. PIFT revealed the presence of IgG anti-platelet antibodies in the patient's serum but the test was negative in the maternal serum. Analyses of HNA-1 and HPA genotypes of the family revealed maternal-neonatal HNA-1a and HPA-3b mismatch. The study of the mother's and patient's sera showed the presence of anti HNA1a, HPA-3b and HLA antibodies specific for HLA-A3 and HLA-B38 antigens. These results suggest that the transplacental passage of maternal HNA-1a, HPA-3b and HLA alloantibodies caused neutropenia and thrombocytopenia in this patient.     

Autoimmune neutropenia in infancy due to anti-NA1 antibody: detection of antibody with immunofluorescence and agglutination test

The sera from two patients with chronic neutropenia in infancy were examined for the presence of antineutrophil antibodies and their specificity against neutrophil antigen by using granulocyte indirect immunofluorescence test and microleukocyte agglutination test. In the microleukocyte agglutination test, the patients' sera reacted with neutrophils from their parents and normal unrelated donors having the neutrophil antigen NA1, but not with neutrophils from NA1- donors. After the absorption of patients' sera with NA1+ neutrophils, the antibody activity was completely abolished, resulting in the confirmation of the anti-NA1 antibody. In contrast, the granulocyte indirect immunofluorescence test showed positive reactions against both NA1+ and NA1- neutrophils, and the specificity for anti-NA1 was found in the results of the sera absorbed with NA1+ neutrophils. This suggested that the absorption experiment might be necessary to determine the specificity of the antibody for neutrophil antigen. Thus, we confirmed two cases with autoimmune neutropenia caused by anti-NA1 antibody. A combination of agglutination and immunofluorescence techniques would be recommended for investigation of neutrophil antibodies against the neutrophil-specific antigen.     

Expression of and responses to CD2 and CD3 in 18‐month‐old children with and without atopic dermatitis

We hypothesize that atopy is associated with a reduced T‐cell function early in life and an imbalance in cytokine production. The purpose of this study was to investigate the expression of and responses to CD2 and CD3 in children who did or did not develop atopic dermatitis early in life. The expression of CD2 and CD3 was analyzed by flow cytometry, and proliferation of CD2 and CD3 was studied by ³H‐thymidine incorporation in phytohaemagglutinin (PHA)‐ and anti‐CD3‐stimulated peripheral blood mononuclear cells (PBMC) of 18‐month‐old children, 25 with and 29 without atopic dermatitis. Exogenous interleukin (IL)‐2 was added to compensate for possible functional differences in accessory cells. Anti‐CD3‐induced secretion of IL‐4, IL‐5, IL‐6, IL‐10, IL‐13, and interferon‐γ (IFN‐γ) was analyzed by enzyme‐linked immunosorbent assay (ELISA). Atopy was associated with a low proportion of CD2⁺ lymphocytes. Responsiveness to PHA, which activates lymphocytes partly via the sheep erythrocyte receptor, CD2, was reduced in the allergic children. The anti‐CD3‐induced proliferation declined more rapidly with antibody dilution in the allergic than in the non‐allergic children. Atopic dermatitis was associated with high levels of anti‐CD3‐stimulated IL‐5 secretion. The IL‐4/IL‐10 and IL‐4/IFN‐γ ratios were higher in children with elevated total immunoglobulin E (IgE) levels. Skin prick test‐negative children with eczema produced higher levels of IL‐10 than skin prick test‐positive children. In conclusion, atopic children have a reduced T‐cell function. Atopic dermatitis is associated with increased IL‐5 production, while high total IgE levels are associated with high IL‐4/IFN‐γ and IL‐4/IL‐10 ratios.     

Neutrophil agglutinins in idiopathic chronic neutropenia of early childhood

Twelve patients with chronic neutropenia, ranging in age from 7 to 27 months, were studied for circulating antineutrophil autoantibodies. Absolute neutrophil counts ranged from 0 to 500/cu mm. None of the patients was transfused or had a history of prior drug ingestion. Edetic acid-microagglutination was employed to detect leukocyte antibodies. Sera from six of 12 patients contained antineutrophil antibodies, four reacting with neutrophils from the father and two from the mother. Patient sera also reacted with neutrophils of several unrelated normal volunteers. Four of the six patient sera with antineutrophil antibodies also reacted with autologous neutrophils. The duration of neutropenia was seven months in one patient with antibody whose neutropenia resolved. Patients with neutrophil autoantibody did not clinically differ from those without demonstrable antibody. The coexistent fall in leukoagglutinin titer and rise in neutrophil counts in one patient suggested an etiologic role for this antibody. Detection and proper diagnosis have important therapeutic implications.     

Clinical and biologic effects of granulocyte colony stimulating factor in the treatment of myelokathexis.

Successful treatment of a patient with myelokathexis, a rare form of chronic neutropenia associated with recurrent infections, is described. Rapid mobilization of bone marrow neutrophils and improved myeloid morphologic features were observed after treatment with human granulocyte colony stimulating factor. Transient thrombocytopenia and bone pain were observed during treatment. Although neutrophil chemotaxis, superoxide production, and FcRIII surface expression were reduced, the patient improved clinically after restoration of a normal neutrophil count.     

Administration of recombinant human granulocyte-colony stimulating factor to septic neonates induces neutrophilia and enhances the neutrophil respiratory burst and β2 integrin expression Results of a randomized controlled trial

The objective of this study was to investigate the effect of treatment with recombinant human granulocyte-colony stimulating factor (rhG-CSF) on the neutrophil count and function of preterm neonates with documented sepsis. For this purpose 62 preterm neonates with proven sepsis and 19 healthy preterm ones were studied. Of the 62 patients, 27 septic neonates had an absolute neutrophil count (ANC) >5000/mm³ (group A) and were scheduled not to receive rhG-CSF and 35/62 had an ANC <5000/mm³ (n= 35) and were randomly assigned either to receive rhG-CSF (group B) or not to receive it (group C). rhG-CSF (10 μg/kg) was administered for 3 consecutive days (0, 1, 2). The ANC, plasma levels of G-CSF (ELISA), neutrophil respiratory burst activity (NRBA) and neutrophil expression of CD11a, CD11b and CD11c (flow cytometry) were measured in all septic neonates on days 0 (onset of sepsis), 1, 3 and 5 and in the healthy neonates once within the first 2 days of life. We found that on day 0, G-CSF levels of all groups of septic neonates were significantly higher than those of the healthy ones. The highest levels were observed in group A. NRBA was diminished only in groups B and C and the expression of CD11a and CD11c was reduced in all groups of septic neonates. Administration of rhG-CSF resulted in a rapid and significant increase in ANC, NRBA and CD11a, CD11b and CD11c expression that persisted throughout the follow up. Conclusion The administration of granulocyte colony stimulating factor to septic neonates significantly increases the absolute granulocyte count and enhances the neutrophil respiratory burst and β₂ integrin expression. Received: 25 March 1997 and in revised form: 5 August 1997 / Accepted: 14 October 1997     

Heterozygous M1V variant of ELA-2 gene mutation associated with G-CSF refractory severe congenital neutropenia

Severe congenital neutropenia is an autosomal recessive disorder characterized by maturation arrest at the promyelocyte/myelocyte phase in the bone marrow, absolute neutrophil count <0.5 × 10⁹/L and recurrent bacterial infections. Homozygous mutations of either HAX‐1 or ELA‐2 have been described. We report the case of a premature male infant with congenital neutropenia, associated with multiple infections, refractory to treatment with granulocyte colony stimulating factor who subsequently underwent matched sibling donor stem‐cell transplant. He was found to be heterozygous for the M1V variant of the ELA‐2 gene that we postulate to be causative for his severe neutropenia. Pediatr Blood Cancer 2011; 57: 514–515. © 2011 Wiley‐Liss, Inc.     

Infliximab regulates monocytes and regulatory T cells in Kawasaki disease

Background

The effect of infliximab (IFX ) on immune cells has not been fully reported in Kawasaki disease (KD ). To investigate the mechanism of IFX in KD , we examined changes in the abundance of CD 14⁺CD 16⁺ activated monocytes, regulatory T cells (T_reg) cells, and T‐helper type 17 (Th17) cells following treatment with IFX .

Methods

We collected peripheral blood from patients with i.v. immunoglobulin (IVIG )‐resistant KD and analyzed absolute CD 14⁺CD 16⁺ monocyte, T_reg (CD 4⁺CD 25⁺FOXP 3⁺) and Th17 cell (CD 4⁺IL ‐17A⁺) counts on flow cytometry. We also measured changes in serum soluble interleukin (IL )‐2 receptor (IL ‐2R), IL ‐6, and tumor necrosis factor (TNF )‐α on enzyme‐linked immunosorbent assay.

Results

T_reg cells and Th17 cells significantly increased after IFX treatment compared with baseline (126 ± 85 cells/μL vs 62 ± 53 cells/μL, P < 0.01; 100 ± 111 cells/μL vs 28 ± 27 cells/μL, P < 0.05, respectively). In contrast, in a subgroup of patients with CD 14⁺CD 16⁺ monocytes above the normal range before IFX , the CD 14⁺CD 16⁺ monocytes significantly decreased following IFX treatment (72 ± 51 cells/μL vs 242 ± 156 cells/μL, P < 0.05).. Serum TNF ‐α did not change, but soluble IL ‐2R and IL ‐6 decreased after IFX treatment.

Conclusion

IFX could downregulate activated monocytes and upregulate T_reg cells towards the normal range. IFX treatment thus contributes to the process of attenuating inflammation in KD .

     

Neutrophil Receptors

We studied two interesting patients with neutrophil dysfunction: one is a patient with hyper-IgE syndrome with the serum inhibitor which belongs to IgE class and the other is characterized by defective phagocytosis confined to S. aureus. These patients suggested to us the presence of IgE receptors and receptors for S. aureus on neutrophils. The presence of IgE receptors on neutrophils was proved by the fact that neutrophils preincubated with 10 μg of pure IgE generated O^-₂ on stimulation with F(ab')₂, fragments of pure anti-K chain antibody or anti-K chain antibody. The presence of IgE receptors was also suggested by the suppressive effect of IgE soluble immune complexes on neutrophil chemotaxis. Neutrophils of the patient with defective phagocytosis confined to S. aureus could not generate O^-₂ with unopsonized S. aureus, while control neutrophils generated a significant amount of O^-₂ on addition of unopsonized S. aureus. Colchicine treated control neutrophils also could not generate O^-₂ by unopsonized S. aureus. These data suggested the presence of receptors for S. aureus on neutrophils.     

TCR α+β+/CD19+ cell–depleted hematopoietic stem cell transplantation for pediatric patients

TCR α⁺β⁺/CD19⁺ cell depletion is an emerging technique for ex vivo graft manipulation in HSCT. We report 20 pediatric patients who underwent TCR α⁺β⁺/CD19⁺ cell–depleted HSCT in four Australian centers. Conditioning regimen was dependent on HSCT indication, which included immunodeficiency (n = 14), Fanconi anemia (n = 3), and acute leukemia (n = 3). Donor sources were haploidentical parent (n = 17), haploidentical sibling (n = 2), or matched unrelated donor (n = 1). Mean cell dose was 8.2 × 10⁸/kg TNC, 12.1 × 10⁶/kg CD34⁺ cells, and 0.4 × 10⁵/kg TCR α⁺β⁺ cells. All patients achieved primary neutrophil and platelet engraftment, with average time to neutrophil engraftment 11 days (range 8‐22) and platelet engraftment 24 days (range 12‐69). TRM at 1 year was 15%. Rate of grade II‐IV aGVHD at 1 year was 20% with no grade III‐IV aGVHD seen. CMV reactivation occurred in 81% of CMV‐positive recipients, with one patient developing CMV disease. Average time to CD4 recovery (>400 × 10⁶/L) was 258 days. Overall survival for the cohort at 5 years was 80%. This report highlights the initial experience of TCR α⁺β⁺/CD19⁺ cell–depleted HSCT in Australian centers, with high rates of engraftment, low rates of aGVHD, and acceptable TRM.     

Etiology of neutrophilic granulocytic hypoplasia in a case of large granular lymphocytic leukemia with paraproteinemia

The association between large granular lymphocytic leukemia (LGLL) and neutropenia is poorly understood. We attempted to assess whether neutropenia in LGLL with paraproteinemia has a different etiology than LGLL without paraproteinemia. We found neither direct serum inhibition of granulocyte/monocyte-colony forming units in vitro nor increased immunoglobulin binding to granulocytic neutrophils, neutrophil precursors, or granulocyte/monocyte-colony stimulating factor. Clonogenic assay experiments suggested that suppression of the patient's granulocyte/monocyte-colony forming units by the neoplastic T-cells and decreased granulocyte/monocyte-colony stimulating factor production contributed to the pathogenesis of neutropenia in this particular case. © 1994 Wiley-Liss, Inc.     

Interleukin-15 enhances CD4+ CD45RA+ expression on umbilical cord blood mononuclear cells

The reduced incidence of graft‐vs.‐host disease following umbilical cord blood (CB) transplantation may be related to the functional immaturity of newborn T cells expressing mainly the naive CD45RA phenotype. Expansion of CD4⁺ CD45RA⁺ T cells using cytokines may benefit neonates and infants with human immunodeficiency virus (HIV) infection, as a preferential decline in CD4⁺ CD45RA⁺ cells has been noted as HIV disease progresses. The aim of the study was to investigate the effect of interleukin (IL)‐15, a novel cytokine similar to IL‐2 in biological activities, on CD45RA/RO expression and apoptosis in umbilical cord blood (CB) and adult peripheral blood (APB) mononuclear cells (MNCs). Prior to culture, CB MNCs contained a greater number of CD4⁺ CD45RA⁺ cells and fewer CD4⁺ CD45RO⁺ cells than did APB MNCs. When incubated with RPMI‐1640 containing 10% fetal calf serum for 7 days, the percentage of CD45RA⁺ cells within CD4⁺ T cells (%CD45RA⁺/CD4⁺) significantly decreased compared to that of fresh CB MNCs. IL‐15 exerted a dose‐dependent increase of %CD45RA⁺/CD4⁺ and a corresponding decrease of %CD45RO⁺/CD4⁺ in CB MNCs, an effect not observed with APB MNCs treated with IL‐15. The percentages of CD45RA⁺ and CD45RO⁺ expression within CD8⁺ cells, however, were not influenced by IL‐15, in either CB or APB MNCs. A greater number of CB MNCs underwent apoptosis than did APB MNCs after 7 days of culture in RPMI‐1640 containing 10% fetal calf serum. IL‐15 did not inhibit apoptosis but induced proliferation comparable to that achieved in APB MNCs. The ability of IL‐15 to preferentially enhance the proliferation of CD4⁺ CD45RA⁺ cells in CB MNCs suggests a role for immunomodulative therapy in HIV‐infected newborns and infants.     

Reduced expression of CD69 and adhesion molecules of T lymphocytes in asthmatic children receiving immunotherapy

T lymphocytes play a fundamental role in the initiation and regulation of chronic inflammatory responses in patients with asthma. CD69 is an early marker of T‐cell activation. The levels of intercellular adhesion molecule‐1 (ICAM‐1, CD54) and L ‐selectin have been reported to increase in patients with allergic diseases and asthma. The present study was therefore undertaken to investigate the expression of CD69, CD54, and L ‐selectin by T lymphocytes of children with asthma, before and after immunotherapy. Eighteen children newly diagnosed with asthma, 11 good and nine poor responders to immunotherapy, and 16 normal subjects, were enrolled in this study. The percentages of CD69⁺, CD54⁺, and CD62L⁺ cells in T lymphocytes were measured by using flow cytometry. The levels of CD69, CD54, and CD62L in serum and culture supernatants were determined by using enzyme‐linked immunosorbent assay (ELISA). The expression of CD69 and CD54 on CD3⁺ T lymphocytes was significantly higher in children with asthma than in control patients. All the patient groups expressed (spontaneously and following stimulation with phorbol myristate acetate and ionomycin together with mite‐extract proteins) greater amounts of CD69 and CD54 than did control subjects. With long‐term immunotherapy, the percentages of CD69⁺ and CD54⁺ T lymphocytes were significantly lower in patients with a good response to immunotherapy. Our results also showed significantly lower serum L ‐selectin levels following immunotherapy. In conclusion, successful immunotherapy resulted in decreased expression and production of CD69 and CD54. These results may explain, in part, the clinical efficacy of immunotherapy.     

Immunodeficiency with recurrent panlymphocytopenia,impaired maturation of B lymphocytes,impaired interaction of T and B lymphocytes,and impaired integrity of epithelial tissue: A variant of idiopathic CD4+ T lymphocytopenia?

Idiopathic CD4⁺ T lymphocytopenia (ICL) has been defined as a cause of immunodeficiency with a variable clinical course and an unknown etiology. Here we describe a now 18‐year‐old boy with ICL, chronic mucocutaneous candidiasis (CMC), recurrent abscesses, and relapsing aphthous and ulcerous lesions. In addition to ICL the patient frequently showed a panlymphocytopenia. An increased percentage of γ⁺δ⁺ T lymphocytes and IgD⁺ IgM⁺ B lymphocytes, and a decreased percentage of CD21⁺ B lymphocytes, were observed. In vitro assays showed normal T‐cell responses to candidin and T‐cell mitogens, but impaired B‐cell responses to pokeweed mitogen (PWM). B‐cell maturation after stimulation with Staphylococcus aureus Cowan I (SAC) and interleukin 2 (IL‐2) was nearly normal. The clinical course of the patient improved substantially on administration of constant low‐dose therapy with fluconazole.     

A novel phenotype variant of severe congenital neutropenia caused by G6PC3 deficiency

Severe congenital neutropenia type 4 (SCN4) is associated with mutations in the G6PC3 gene. To date, all patients bearing the p.Gly260Arg variant of the G6PC3 gene show heart defects. Here, we present a case of the p.Gly260Arg variant in a patient who did not have structural or functional heart anomalies. Treatment with granulocyte colony‐stimulating factor recovered the absolute neutrophil count and neutrophil functional competence. Pediatr Blood Cancer 2013; 60: E29–E31. © 2013 Wiley Periodicals, Inc.     

Comparison of FDG-PET scans to conventional radiography and bone scans in management of Langerhans cell histiocytosis

Neonatal thrombocytopenia or neutropenia may result from passive transfusion of maternally derived antibodies. Antibodies against platelet antigens are commonly associated with neonatal alloimmune thrombocytopenia (NAIT), and anti‐neutrophil antibodies are frequently identified in alloimmune neonatal neutropenia (ANN). Combined alloimmune cytopenias in the newborn are rarely reported; even fewer reports document human leukocyte antigen (HLA) antibodies as a potential cause of neonatal thrombocytopenia or neutropenia. We describe neutropenia and thrombocytopenia in a newborn associated with markedly elevated maternal HLA antibodies in the absence of anti‐neutrophil or anti‐platelet antibodies to highlight consideration of HLA antibodies in the pathogenesis of ANN and NAIT. Pediatr Blood Cancer 2009;53:97–99. © 2009 Wiley‐Liss, Inc.     

Determination of T‐cell subpopulations and intracellular cytokine production (interleukin‐2, interleukin‐4, and interferon‐γ) by cord blood T‐lymphocytes of neonates from atopic and non‐atopic parents

This report describes the results of a prospective study on immunological markers in cord blood for the prediction of allergic diseases in children. First we evaluated methodological aspects of the flow cytometric technique on cord blood cytokine measurements. Subsequently, the T‐cell subsets and percentage of cytokine‐producing cord blood T‐helper (Th) and T‐suppressor/cytotoxic lymphocytes of neonates from atopic and non‐atopic parents were compared. A group of 33 healthy, full‐term newborn infants of whom 23/33 were at risk for atopy (i.e. having at least one parent with one or more atopic symptoms and positive specific immunoglobulin E [IgE] to at least one common inhalant allergen) was studied. A flow cytometric technique was used to analyze cord blood T‐cell subsets and to determine the percentage of interleukin (IL)‐2‐, IL‐4‐, and interferon‐γ (IFN‐γ)‐producing cord blood Th and T‐suppressor/cytotoxic lymphocytes following stimulation with phorbol 12‐myristate 13‐acetate (PMA) and ionomycin. The percentage of CD3 (T lymphocytes), CD3⁺ CD4⁺ (Th lymphocytes), CD3⁺ CD8⁺ (T‐suppressor/cytotoxic lymphocytes), CD19⁺ (B lymphocytes), CD3⁺ CD4⁺ CD45RO⁺ (memory Th lymphocytes), and CD3⁺ CD4⁺ CD45RA⁺ (naive Th lymphocytes) cells was unrelated to parental atopic status. PMA stimulation augmented the percentage of IL‐2‐ and IFN‐γ‐producing Th and T‐suppressor/cytotoxic lymphocytes, whereas the number of IL‐4‐producing T lymphocytes remained very low or undetectable. No differences in the percentage of IL‐2‐, IL‐4‐ and IFN‐γ‐producing Th and T‐suppressor/cytotoxic lymphocytes were found between neonates from atopic and non‐atopic parents. These results will be re‐evaluated when the atopic status of the children at the age of 1 and 2 years can be assessed.     

CD4+CD25(high) Treg cells in peripheral blood during remission and exacerbation of allergic asthma in children

Aim: To determine the percentage of CD4⁺CD25^high Treg cells in peripheral blood CD4⁺ T cells of allergic asthmatic children during disease remission and exacerbation. Methods: Peripheral blood mononuclear cells (PBMC) and serum samples were collected from 6‐ to 11‐year‐old children with mild‐to‐moderate allergic asthma (n = 34) and from healthy controls (n = 15). CD4⁺CD25^high T cells in PBMC were detected by flow cytometry. Total and specific IgE in serum were analysed by enzyme‐amplified chemiluminescence, and IL‐2 was measured by ELISA. Results: There was no significant difference in CD4⁺CD25^high T‐cell proportions between asthmatic children in exacerbation and remission as compared with controls. CD4⁺CD25^high T‐cell percentages were not correlated with total and specific IgE. IL‐2 was elevated in both disease remission and exacerbation but did not correlate significantly with CD4⁺CD25^high T‐cell percentages. Conclusion: CD4⁺CD25^high T‐cell proportion in the peripheral blood of total CD4⁺ T cells is not reduced in children with allergic IgE‐mediated asthma and does not differ between disease remission and exacerbation.     

全身炎症反应综合征患儿中性粒细胞淋巴细胞CD11b表达意义

目的：探讨全身炎症反应综合征（SIRS）患儿血液中性粒细胞、淋巴细胞CD11b表达对诊断和判断病情的意义。方法：用流式细胞术检测36例SIRS患儿血液中性粒细胞、淋巴细胞CD11b表达水平,28例一般感染性疾病,不符合SIRS诊断标准的患儿作为对照组。比较各指标对诊断SIRS的灵敏度、特异度,评价它们对诊断SIRS和判断病情的价值。结果：急性期SIRS组中性粒细胞CD11b表达为（96.7±8.1）%,高于对照组的（85.1±5.1）%,差异有显著性（P＜0.05）。中性粒细胞CD11b＞92.24%为阳性标准,诊断SIRS敏感性和特异性分别为97.2%,92.9%。急性期SIRS组淋巴细胞CD11b表达为(13.4±8.6)%,对照组为（19.2±6.4）%,差异有显著性（P＜0.05）;其中严重脓毒症组淋巴细胞CD11b表达为（7.3±3.0）%,低于非感染SIRS组的（19.3±2.9）%和脓毒症组的(15.9±12.5)%（P＜0.01）。恢复期SIRS组淋巴细胞CD11b表达为（13.35±4.89）%,对照组为（13.8±4.7）%,差异无显著性（P＞0.05）。结论：中性粒细胞CD11b可作为诊断SIRS的可靠指标,淋巴细胞CD11b表达下调可能是SIRS患儿病情加重的信号。［中国当代儿科杂志,2009,11（7）：540-542］