Prognostic implications for direct platelet-associated IgG in childhood idiopathic thrombocytopenic purpura

To determine the value of the direct platelet associated IgG (PAIgG) level as a prognostic indicator in childhood idiopathic thrombocytopenia purpura (ITP), 18 children with ITP were studied. Ten of the 18 had PAIgG levels measured at diagnosis, before any therapy. Of these 10 patients, six (Group I) had an acute course, with a mean initial platelet count of 15 X 10(9)/liter and a mean initial PAIgG level of 330.9 fg/plt. Four patients (Group II) had a chronic course, with a mean initial platelet count of 11 X 10(9)/liter and a mean initial PAIgG level of 38.3 fg/plt. There was no significant difference between the mean initial platelet count of Groups I and II (p greater than 0.10), but the initial PAIgG levels in those patients with an acute course were significantly higher than the levels in those patients with a chronic course (p less than 0.05). Of the original 18 patients, nine were splenectomized for chronic thrombocytopenia, with normalization of the platelet count in all instances. Of these splenectomized patients, five had platelet counts and PAIgG levels measured before and after splenectomy. All five had normal PAIgG levels following splenectomy. The PAIgG level is a good prognostic indicator for the clinical course of childhood ITP. A high PAIgG level suggests an acute course while a modestly elevated level suggests a chronic course. The PAIgG level normalizes in remission after splenectomy.     

Platelet antibody in prolonged remission of childhood idiopathic thrombocytopenic purpura

Evaluations were performed in 20 patients with childhood idiopathic thrombocytopenic purpura (ITP) who remained in remission longer than 12 months. The mean duration of follow-up from diagnosis was 39 months (range 17 to 87 months). Eleven patients (four girls) in group 1 had an acute course of ITP, defined as platelet count greater than 150 X 10(9)/L within 6 months of diagnosis. Nine patients (five girls) in group 2 had a chronic course, defined as platelet count less than 150 X 10(9)/L for greater than or equal to 1 year or requiring splenectomy in an attempt to control hemorrhagic symptoms. Mean age at diagnosis and duration of follow-up were similar for both groups. Platelet count and serum (indirect) platelet-associated IgG (PAIgG) levels were normal in all 20 patients at follow-up. Both direct and indirect PAIgG levels were measured using a 125I-monoclonal anti-IgG antiglobulin assay. All had normal direct PAIgG levels, except for one patient in group 1 who had a borderline elevated value of 1209 molecules per platelet. These data suggest that the prevalence of elevated platelet antibodies is low during sustained remission without medication in patients with a history of childhood ITP. These data may be relevant for pregnant women with a history of childhood ITP, with regard to the risk of delivering an infant with thrombocytopenia secondary to transplacental passage of maternal platelet antibody.     

Platelet-associated immunoglobulin G in childhood idiopathic thrombocytopenic purpura

Childhood ITP is an acquired hemorrhagic disorder with a heterogeneous clinical course. We measured PAIgG levels in 20 children with ITP (7 acute, 13 chronic). Both groups had significantly greater PAIgG values than age-matched normal subjects and thrombocytopenic controls (P less than 0.001). In addition, PAIgG values in chronic ITP were significantly lower than those in acute ITP (P less than 0.003). Serial PAIgG values were obtained in some patients; most returned to normal in association with clinical recovery. The measurement of PAIgG is useful in the diagnosis and follow-up of childhood ITP. PAIgG values may assist in differentiating acute and chronic disease in children.     

Platelet-associated immunoglobulin G in childhood idiopathic thrombocytopenic purpura

Platelet-associated IgG was studied in children with acute and chronic ITP and in patients with thrombocytopenic SLE, using the microtiter solid-phase radioimmunoassay. Of the children with acute ITP, 85% had elevated PAIgG levels. The degree of elevation of PAIgG at onset of disease did not correlate with the development of chronicity. Of the children with acute ITP, clinically and hematologically indistinguishable from the rest, 15% had normal PAIgG values. All of 22 children with chronic ITP had elevated PAIgG values. Although there was good correlation between the platelet count and the PAIgG value in children with chronic ITP, the association was not as striking in those with acute ITP; thus, factors in addition to the level of PAIgG may contribute to the thrombocytopenia in the latter group. Patients with SLE and thrombocytopenia had higher values of PAIgG than would be predicted from the platelet count; the PAIgG value is probably not the only factor determining the degree of immune thrombocytopenia.     

Evaluation of a simple immunodiffusion technique for quantitation of platelet-associated immunoglobulin G in childhood immune thrombocytopenias

Platelet-associated IgG (PAIgG) was quantitated in 33 children with immune thrombocytopenia and platelet counts less than 100 X 10(9)/liter using a simple radial immunodiffusion (RID) assay. Elevated PAIgG levels were found in 76% (16/21) of children with acute idiopathic thrombocytopenic purpura (ITP), 88% (7/8) of children with chronic ITP, and all four children studied with systemic lupus erythematosus and thrombocytopenia. Normal PAIgG values were found in children with the following disorders: malignancy and chemotherapy-related thrombocytopenia; ITP in remission (platelet counts greater than 150 X 10(9)/liter); various nonimmune hematologic disorders and juvenile rheumatoid arthritis, these children having normal platelet counts. In children with acute ITP, elevated PAIgG values at initial presentation fell to within the normal range when clinical remission occurred. The RID assay can be easily established in most hematology laboratories and has the advantage that solubilized "test" platelets used in the assay can be stored frozen prior to analysis. We conclude that this simple technique is of value in the evaluation of childhood thrombocytopenic states and yields results comparable to those reported using more complex antiplatelet antibody assays.     

特发性血小板减少性紫癜患儿血小板生成素及其受体基因转录水 …

目的 探讨急性特发性血小板减少性减少性紫癜（ＡＴＴＰ）患儿血小板生成素（ＴＰＯ）及血小板ＴＰＯ受体ｃ－ＭＰＬ ｍＲＮＡ基因转化水平变化的意义。方法 采用ＥＬＩＳＡ法检测血清ＴＰＯ、血小板相关抗体（ＰＡＩｇＧ）水平;半定量ＲＴ－ＰＣＲ法检测外周血血小板ｃ－ＭＰＬ ｍＲＮＡ的相对量。结果 ＡＴＴＰ患儿初治时血浆ＴＰＯ水平增高,血小板ｃ－ＭＯＬ ｍＲＮＡ较低;以大剂量甲基强的松龙冲击治疗后,位随血小板计     

选择性脾切除术治疗儿童ITP的疗效探讨

目的探讨近年来儿童慢性特发性血小板减少性紫癜(ITP)患者行选择性脾切除术的有效性及安全性。方法收集1986年～2000年新华医院及上海儿童医学中心行选择性脾切除术治疗ITP的患儿资料,以术后血小板计数的稳定最低值判断疗效,回顾性研究其相关因素。结果16例慢性ITP患儿行选择性脾切除术,其中9例男孩,7例女孩。治愈7例(43.75%),好转5例(31.25%)。术后随访未有感染并发症发生。治愈患儿的术后血小板峰值均超过400×109/L,而其余患儿中仅2例超过400×109/L,经Fisher精确检验,两组间有显著差异(P<0.01)。结论选择性脾切除术是治疗儿童慢性ITP安全有效的方法。脾切除术后的疗效与术后血小板最高峰值相关,术后高的血小板计数峰值将提示着良好的预后。     

Kabuki make-up syndrome associated with chronic idiopathic thrombocytopenic purpura

Although susceptibility to infections in Kabuki make-up syndrome (KMS) has frequently been reported, there have been few immunological studies. We describe a 14 year old girl with KMS exhibiting chronic idiopathic thrombocytopenic purpura (chronic ITP), including immunological studies. Corticosteroid therapy was not effective therefore splenectomy was performed. The patient's platelet count increased transiently. Immunological studies revealed normal T cell functions and low serum immunoglobulin A (IgA) levels. Because of the abnormalities of B cell functions in chronic ITP and low serum IgA levels in our patient, we speculate that there may be some abnormalities of humoral immunity in KMS.     

Soluble P-selectin,interleukin 6, and thrombopoietin levels in children with acute and chronic idiopathic thrombocytopenic purpura and their relationship with mega-dose methylprednisolone therapy: a pilot study

We observed less severe symptoms in patients with chronic idiopathic thrombocytopenic purpura (ITP) than in patients with acute ITP with similar platelet counts. Thrombopoietin (TPO), soluble P-selectin, soluble P-selectin per platelet, and interleukin 6 (IL-6) were evaluated in children with ITP before treatment in 16 acute and 22 chronic cases and after treatment in 10 acute and chronic cases who received mega-dose methylprednisolone. The levels of IL-6, soluble P-selectin, soluble P-selectin per platelet, and platelet count were similar in acute and chronic ITP (P > 0.05) but TPO in acute ITP was higher than that of the patients with chronic ITP (P < 0.05). The posttreatment IL-6 and TPO declined (P < 0.05), but soluble P-selectin and platelet count increased (P < 0.05). Posttreatment soluble P-selectin per platelet levels were higher than the normal values (P < 0.05). These results suggest that IL-6, soluble P-selectin, and soluble P-selectin per platelet are not responsible for the milder symptoms in chronic than in acute ITP. Mega-dose methylprednisolone seems to keep the soluble P-selectin levels elevated.     

Elective splenectomy in children with idiopathic thrombocytopenic purpura

PURPOSE: The aim of this study was to review the safety and efficacy of elective splenectomy in children with idiopathic (immune) thrombocytopenic purpura (ITP). METHODS: The authors reviewed the medical records of children with ITP treated with elective splenectomy at Children's Medical Center of Dallas since 1961. Indication for splenectomy was symptomatic thrombocytopenia unresponsive to medical management. RESULTS: Thirty-eight evaluable patients who had elective splenectomy for ITP were identified. Twenty-one (55%) were girls and 17 (45%) were boys. Twenty-two had splenectomy since January 1990. Age at diagnosis ranged from 6 months to 15.9 years (median 9 years), and age at splenectomy ranged from 3.6 to 16.4 years (median 11.8). Laparoscopic splenectomy was performed in 11 patients. No patient died and only one (2.6%) had postoperative hemorrhage. There were no other complications related to surgery. No cases of postsplenectomy sepsis were observed. At follow-up ranging from 1 month to 19.9 years (median 2.1 years), 29 patients (76.3%) had a normal platelet count (>150 x 109/L) and 4 (10.5%) had a platelet count between 50 and 150 x 109/L. Only two of the five (13.2%) remaining patients who continued to have a platelet count less than 50 x 109/L had hemorrhagic manifestations necessitating intermittent therapy with corticosteroids. CONCLUSION: Laparoscopic or open splenectomy is a safe and effective procedure for children with chronic or refractory ITP and should be considered when medical management fails or causes excessive toxicity.     

特发性血小板减少性紫癜患者血小板抗体及淋巴细胞亚群的研究

目的探讨血小板相关抗体(PAIgG)和T淋巴细胞亚群的变化,在特发性血小板减少性紫癜(ITP)免疫发病机制中的作用、临床意义。方法采用间接免疫荧光法测定30例ITP患者及20例正常对照组的PAIgG,20例ITP患儿治疗后复查PAIgG。同时采用流式细胞仪直接免疫荧光法检测外周T血淋巴细胞亚群。结果ITP组PAIgG阳性率为80%,正常对照组为20%(P<0.001),ITP组PAIgG明显高于正常对照组(P<0.001),20例ITP患儿治疗后复查PAIgG,其数值明显下降,差异有显著性(P<0.001)。T淋巴细胞亚群中,ITP组CD3、CD4、CD4/CD8显著低于正常对照组(P<0.01),CD8则显著高于正常对照组(P<0.01)。结论抗血小板相关抗体对提高ITP的诊断、疗效及预后的判断有一定的实用价值,T淋巴细胞亚群的变化能较好的反映ITP的病理机制。     

Idiopathic thrombocytopenic purpura of childhood

Idiopathic thrombocytopenic purpura (ITP) is a benign hemorrhagic disorder characterised by peripheral thrombocytopenia and increased megakaryocytes in the bone marrow. The exact pathogenesis of ITP is not well understood. The adherence of viral induced immune complexes to the platelet membrane is thought to trigger the phagocytosis of damaged platelets by macrophages in the reticuloendothelial system. The role of platelet associated IgG in the pathogenesis of ITP is under investigation. Although spontaneous recovery is observed in 80–90% of patients, a short course of steroid therapy is recommended to reduce the duration of thrombocytopenia. The steroids however, have no influence on the course or outcome of the disease, and their possible role in reducing the incidence of intracranial hemorrhage (ICH) is unknown. Emergency management of patients presenting with signs and symptoms suggestive of ICH is essential to prevent the fatal outcome. Approximately 10–20% of patients develop chronic ITP. Splenectomy, considered the treatment of choice in these patients, is not always curative. The post-splenectomy sepsis also imposes a great risk for these individuals. Recent experience with intravenous immunoglobulin (IV IgG) treatment indicates that the splenectomy could safely be deferred, or even avoided in chronic ITP. The use of IV IgG in acute ITP is being investigated.     

Chronic immune thrombocytopenic purpura in children: a survey of the canadian experience

BACKGROUND: Immune thrombocytopenic purpura (ITP) in children is a common pediatric bleeding disorder with heterogeneous manifestations and a natural history that is not fully understood. To better understand the natural history of chronic ITP and detect response trends and outcomes of therapy, we conducted a 10-year retrospective survey of children from age 1 to 18 years with a diagnosis of chronic ITP. RESULTS: Data on 198 patients from 8 Canadian Pediatric Hematology/Oncology centers were analyzed. The majority of patients were female (58%), and were previously diagnosed with acute (primary) ITP (85%). The age at diagnosis of chronic ITP ranged from 1.1 to 17.2 years with a mean of 8.2+/-4.4 years. Ninety percent of patients received some form of treatment. Untreated patients had a higher mean platelet count at diagnosis of chronic ITP (P=0.009) despite similarities in mean age at first presentation and mean duration of follow-up. Thirty-four (17%) patients underwent splenectomy. Splenectomized patients tended to be significantly older, had a lower mean platelet count at diagnosis of chronic ITP, and had a longer duration of follow-up. CONCLUSIONS: The results from this study are consistent with published reports.     

Platelet-Associated IgG in Pediatric HIV Infection

Hematologic abnormalities, including thrombocytopenia, are seen in HIV infection. Mi have previously reported elevated platelet-associated IgG (PAIgG) in thrombocytopenia in children associated with human immunodeficiency virus (HIV). In this study we prospectively monitored 40 HIV-infected infants and children to determine the significance of elevated PAIgG levels as they relate to thrombocytopenia. We also examined platelet eluatesfor the presence of HIV antibody and antigen. Of 16 patients with thrombocytopenia, 15 (93.7%) had elevated PAIgG. Of 24 patients with normal platelet counts, 21 (87.5%) had elevated PAIgG. On follow-up, none of the children with normal platelet counts and elevated PAIgG levels developed thrombocytopenia. Examination of the platelet eluates was negative for HIV antibody or P24 antigen. Although the sensitivity of an elevated PAIgG level in predicting thrombocytopenia is 93%, its specificity is only 13%. Elevated PAIgG levels are therefore not causally related to the development of thrombocytopenia in children.     

血小板自身抗体的流式细胞术检测与意义

目前血小板自身抗体的测定方法较为复杂,同时需要较多的血量,因此给儿科临床应用带来一定困难。本文拟应用流式细胞术建立一种简便、快捷、敏感的检测血小板相关抗体的方法。应用荧光素化的羊抗人Ｆ(ａｂ)２段ＩｇＧ抗体结合血小板表面的抗体,应用荧光素化的羊抗鼠ＩｇＧ抗体作为阴性对照。即以直接法测定血小板表面结合的ＩｇＧ。应用流式细胞术测定血小板的平均荧光强度。血小板荧光强度(ＭＦＩ)反映血小板表面ＰＡＩｇＧ的水平。测定正常人和特发性血小板减少性紫癜患儿的血小板平均荧光强度。结果显示:正常对照组的血小板平均荧光强度(ＭＦＩ)为２３．６７±９．１０(道数)。３１例ＩＴＰ组的ＭＦＩ为１０３．６３±３１．４１(道数)。ＩＴＰ病人的血小板荧光阳性率为９０%。治疗有效的病人,随血小板计数的上升,血小板荧光强度逐渐下降。因此,流式细胞术测定血小板抗体是一种快速、简便灵敏的ＰＡＩｇＧ检测方法,可用于免疫性血小板减少性紫癜的辅助诊断和疗效观察。     

Low-dose cyclosporin A therapy in children with refractory immune thrombocytopenic purpura

Although splenectomy is the most effective treatment for chronic idiopathic thrombocytopenic purpura (ITP), many post-splenectomy patients have recurrent thrombocytopenia refractory to multiple medical therapies. Three consecutive patients with relapsed ITP after splenectomy and who were refractory to multiple medical therapies were treated with low dose cyclosporin A (CsA). In all 3 patients, the platelet count increased dramatically within 1 month from the onset of CsA therapy. The only detectable toxicity was hypomagnesemia and mild hypertension in 1 patient. CsA may be efficacious in treating patients with chronic ITP, which is refractory to all medical and surgical therapies currently being used.     

High-Dose Intravenous Immunoglobulin as Single Therapy in a Child with Autoimmune Hemolytic Anemia

Between 1975 and 1992 450 children with idiopathic thrombocytopenic purpura (ITP) were diagnosed, and of those 100 (22%) developed the chronic form of the disease. Approximately half the patients with chronic ITP presented with mild to moderate hemorrhagic manifestations at the onset of purpura (30 cases) andlor later during the course of the disease (25 cases). The incidence of intracranial hemorrhage was 1 %, and the mortality rate due to overwhelming septicemia after splenectomy was also 1%. Overall one-third of the patients received no therapy; two-thirds of them went into spontaneous remission within 8 months to 8 years from the onset of ITP. Steroids given in conventional or high doses (51 cases) achieved a transient (if any) rise in platelet count, but in no case were steroids curative. Remission related to intravenous immune globulin (IVIG) therapy was noticed in 38.5% of the children (10 of 26) after variable courses. The response rate to splenectomy was 95.0%. Ultimately the long-term outcome in children with chronic ITP was as follows: remission, 58 cases (spontaneous, 30; after IVIG therapy, 10; after splenectomy, 18); hemostatic platelet values, 22 cases (spontaneous, 16; after IVIG, 5; after splenectomy, I). Thirteen children were lost in follow-up, and 7 remain thrombocytopenic but asymptomatic. These data indicate that chronic ITP in childhood runs a benign course in most cases and may remit with or without therapy euen several years from onset. Therefore, therapeutic intervention has to be individvalized, and splenectomy, which is not always safe, should be reserved for problematic cases that fail to respond to conventional therapeutic modalities.     

Agenesis of the Corpus Callosum and Neural Crest Tumors

Hematologic abnormalities, including thrombocytopenia, are seen in HIV infection. Mi have previously reported elevated platelet-associated IgG (PAIgG) in thrombocytopenia in children associated with human immunodeficiency virus (HIV). In this study we prospectively monitored 40 HIV-infected infants and children to determine the significance of elevated PAIgG levels as they relate to thrombocytopenia. We also examined platelet eluatesfor the presence of HIV antibody and antigen. Of 16 patients with thrombocytopenia, 15 (93.7%) had elevated PAIgG. Of 24 patients with normal platelet counts, 21 (87.5%) had elevated PAIgG. On follow-up, none of the children with normal platelet counts and elevated PAIgG levels developed thrombocytopenia. Examination of the platelet eluates was negative for HIV antibody or P24 antigen. Although the sensitivity of an elevated PAIgG level in predicting thrombocytopenia is 93%, its specificity is only 13%. Elevated PAIgG levels are therefore not causally related to the development of thrombocytopenia in children.     

Alpha-interferon therapy induces improvement of platelet counts in children with chronic idiopathic thrombocytopenic purpura

PURPOSE: To investigate alpha-interferon (IFN) therapy for children with chronic idiopathic thrombocytopenic purpura (ITP). PATIENTS AND METHODS: Patients with refractory ITP lasting more than 12 months from diagnosis were included if they had platelet counts <50 x 10(9)/L and had received no treatment during the past month. Patients received IFN (3 x 10(6) U/m2 per dose), three times per week for 4 weeks; if partial (<150 x 10(9)/L) or no response was obtained, the same dose was continued for another 8 weeks. In patients with favorable response and subsequent decrease to pre-treatment values, an additional 4 weeks of treatment could be administered. RESULTS: Fourteen patients (ages 4-20 y) receiving 17 IFN courses were included. Mean initial platelet count was 29 +/- 15 x 10(9)/L. A significant increase was achieved during 14 of 17 courses (82.4%). All but two responses were transitory, and platelets returned to initial values after IFN discontinuation (mean 44 +/- 26 days). Considering the best response achieved by each patient, we observed: 1) 10 patients who achieved a sustained improvement of platelet count throughout the treatment period, decreasing to initial values after therapy was stopped; 2) one patient who achieved platelet count >150 x 10(9)/L, remaining with normal platelets at 18 months; 3) one patient who achieved platelet count >150 x 10(9)/L, remaining with platelets between 100 and 140 x 10(9)/L at 48 months; 4) one patient who had no response; and 5) one patient in whom therapy worsened the thrombocytopenia. A mild to moderate flu-like syndrome and a moderate decrease of the absolute neutrophil count were the only side effects observed. CONCLUSION: Interferon therapy induces a significant increase of platelet count and seems to be a valid alternative therapy to attempt the achievement of prolonged remission in refractory ITP, to defer splenectomy in younger children, or to improve platelet count before planned splenectomy.     

Danazol therapy for chronic immune-mediated thrombocytopenic purpura in a patient with common variable immunodeficiency.

We describe a patient with common variable immunodeficiency (CVI) and chronic immune-mediated thrombocytopenic purpura (ITP), refractory to treatment with corticosteroids, splenectomy, and intravenous immunoglobulin. He had a prompt response to danazol, and the platelet counts have been maintained in the normal range with low-dose, alternate-day, danazol therapy. This case provides evidence that danazol is effective in the treatment of chronic ITP in patients with immunodeficiency and indicates that some patients can be maintained on an alternate-day regimen.