Probiotics as an adjuvant treatment in Helicobacter pylori eradication therapy

Over 80% of individuals infected with Helicobacter pylori (H. pylori) are asymptomatic. Increased resistance to antibiotics and decreased compliance to the therapeutic regimens have led to the failure of eradication therapy. Probiotics, with direct and indirect inhibitory effects on H. pylori in both animal models and clinical trials, have recently been used as a supplementary treatment in H. pylori eradication therapy. Probiotics have been considered useful because of the improvements in H. pylori eradication rates and therapy‐related side effects although treatment outcomes using probiotics are controversial due to the heterogeneity of species, strains, doses and therapeutic duration of probiotics. Thus, despite the positive role of probiotics, several factors need to be further considered during their applications. Moreover, adverse events of probiotic use need to be noted. Further investigations into the safety of adjuvant probiotics to H. pylori eradication therapy are required.     

Ethnic and racial difference in Helicobacter pylori infection in patients with immune thrombocytopenia treated at a major urban medical center

Immune thrombocytopenia (ITP) is an autoimmune disorder with a complex immunopathology and pathogenesis characterized by thrombocytopenia and bleeding manifestations. The disorder is separated into primary (idiopathic) ITP and secondary ITP, when associated with other immune or lymphoproliferative disorders and certain chronic infections. Helicobacter pylori (H. pylori) is a recognized bacterial cause of ITP. In regions with high prevalence of infection, bacterial eradication has resulted in improvement in platelet count. However, the prevalence of H. pylori infection and response to antimicrobial therapy in North American ITP patients is reportedly low. We evaluated the prevalence of H. pylori infection in ITP patients diagnosed and treated at a large urban medical center. Eighty-two patients were screened for H. pylori, by stool antigen (n = 54), H. pylori breath test (n = 11), and H. pylori antibodies (n = 16), of which 15 (18.3%) were white non-Hispanic (WNH), 55 (67%) Hispanic (H), 8 (9.8%) Asian (A), and 4 (4.9%) African-American (AA). Of the screened patients, 36/82 (43.9%) tested positive for H. pylori. The prevalence of H. pylori infection within the represented ethnic groups was 2/15 (13%) WNH, 29/55 (52.7%) H, 3/8 (37.5%) A, and 2/4 (50%) AA. There was a significant difference in prevalence of infection comparing WNH and H patients (p = 0.007). There were 36 treated patients, with H. pylori eradication documented in 26 patients. Fifteen of the 26 patients were evaluable for response with 8 of 15 (53%) having clinical responses, 6 complete responses, and 2 partial responses. Our study demonstrates an increased prevalence of H. pylori infection in the Hispanic ITP population with a reasonable platelet response among patients with H. pylori eradication.     

Investigation of platelet apoptosis in adult patients with chronic immune thrombocytopenia

Objectives: Immune thrombocytopenia (ITP) is an acquired and heterogeneous autoimmune-mediated hematological disease typically characterized by a low platelet count. Emerging evidence over the past several years suggests that platelet biogenesis and ageing are regulated, at least in part, by apoptotic mechanisms. However, the association between decreased platelets and apoptosis in ITP patients is poorly understood. To better understand the role of platelet apoptosis in ITP pathophysiology, we investigated apoptotic markers in platelets acquired from 40 chronic ITP patients. Furthermore, the results of ITP patients were compared to those from 40 healthy individuals.

Methods: Markers of apoptosis, including phosphatidylserine (PS) exposure and mitochondrial inner membrane potentials (ΔΨm), were examined using flow cytometry. The expression of pro-apoptotic molecules such as Bak and Bax and anti-apoptotic molecules such as Bcl-xL were determined using quantitative real-time PCR (qRT-PCR) and Western blotting.

Results: Our study demonstrated that the platelet mitochondrial membrane depolarization in chronic ITP patients tended to be higher than in healthy controls. Additionally, the proportion of platelets with surface-exposed PS in chronic ITP was significantly higher than that of controls. The results showed that the expression levels of Bak and Bax were significantly higher in chronic ITP patients than in healthy controls; Bcl-xL expression levels were significantly decreased in the platelets of chronic ITP patients compared to healthy controls.

Discussion and conclusion: study indicates that the enhancement of platelet apoptosis observed in patients with chronic ITP may be one of the pathogenic mechanisms of chronic ITP.     

Circulating plasmacytoid dendritic cells in patients with primary and Helicobacter pylori-associated immune thrombocytopenia

Objectives: Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by the production of autoreactive antibodies against platelet antigens. Although dysfunction of multiple aspects of cellular immunity is considered to be important in the pathogenesis of ITP, it has not been clarified which cell types play a principal role. Methods: We enrolled 46 untreated patients with chronic ITP and 47 healthy adult volunteers, and investigated by flow cytometry the percentage and absolute number of cells in their peripheral blood that participate in the regulation of cellular immunity. These included plasmacytoid dendritic cells (pDCs), myeloid dendritic cells (mDCs), natural killer (NK) cells, natural killer T (NKT) cells, regulatory T (Treg) cells, and Th17 cells. Results: We found a significant reduction in the absolute number of pDCs, but not of mDCs, in patients with ITP when compared with healthy controls (P < 0.001). Reduced numbers of circulating pDCs were observed in both Helicobacter pylori (H. pylori)‐positive and Helicobacter pylori (H. pylori)‐negative patients with ITP. In contrast, there were no significant differences in the numbers of circulating Treg cells, Th17 cells, NK cells, or NKT cells. Interestingly, we observed increases in the number of pDCs after H. pylori eradication by antibiotics in responders but not in non‐responders, while pDCs and mDCs decreased markedly after prednisolone therapy in both responders and non‐responders. In patients without treatment, low pDC numbers persisted during the observational period. Conclusions: We demonstrated that the number of circulating pDCs is low in patients with primary and H. pylori‐associated ITP and that it changes depending on treatment modality. Further investigation is warranted with regard to the role of pDCs in the immunopathogenesis of ITP.     

Intrinsically impaired platelet production in some patients with persistent or chronic immune thrombocytopenia

Persistent or chronic immune thrombocytopenias (P/C‐ITP) are acquired blood disorders lasting more than 3 months or 1 year, respectively. The pathogenesis of these disorders is thought to be immunological. We hypothesized that some patients with P/C‐ITP might have an intrinsic megakaryopoiesis defect. We identified a group of P/C‐ITP patients with acquired isolated mild thrombocytopenia (30–100 × 10⁹/l), undetectable anti‐platelet antibodies, negative autoimmune investigations and no need for treatment. We examined in vitro megakaryocyte differentiation and compared these patients' results with those of acute‐ITP patients and healthy controls. No difference in proliferation, ploidy or expression of surface markers was found. In contrast, P/C‐ITP patients had significantly fewer proplatelet‐forming megakaryocytes. This novel observation demonstrated that some patients diagnosed with P/C‐ITP have an intrinsic megakaryopoiesis defect independent of the bone‐marrow environment. Further investigations are needed to dissect mechanisms underlying this impaired proplatelet formation in these patients.     

Interleukin-17F gene polymorphism in patients with chronic immune thrombocytopenia

Introduction: IL‐17F is a novel inflammatory cytokine and plays an important role in some autoimmune diseases. We investigated the association between chronic ITP and the frequency of the single‐nucleotide polymorphism rs763780 (7488T/C), which causes a His‐to‐Arg substitution at amino acid 161. Patients and methods: We examined 102 patients (men/women, 40/62; median age, 42) diagnosed with chronic ITP and 188 healthy controls (men/women, 78/110; median age, 38). Genotyping was determined by the polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) technique. Results: Compared with the control group, patients with chronic ITP had a significantly lower frequency of the IL‐17F 7488CC genotype (0% vs. 4.8%, P < 0.05). The number of IL‐17F 7488C alleles among the patients with chronic ITP was also significantly lower than in the control group (8.7% vs. 15.2% OR = 0.48, 95%CI = 0.27–0.84, P = 0.016). Furthermore, patients with the IL‐17F 7488TT genotype showed a severe thrombocytopenic state (platelet count < 10×10⁹/L) at diagnosis than those with the IL‐17F 7488TC genotype (20.9% vs. 0%, P = 0.04). Conclusion: These findings suggest that the IL‐17F 7488 T allele is significantly associated with the development of chronic ITP, suggesting a role for IL‐17F in the pathogenesis of chronic ITP.     

Helicobacter pylori eradication in patients with chronic immune thrombocytopenic purpura

AIM:To assess the effect of Helicobacter pylori(H.pylori)eradication on platelet counts in patients with chronic immune thrombocytopenic purpura(cITP).METHODS:A total of 36 cITP patients were included in the study.The diagnosis of H.pylori was done by rapid urease test and Giemsa staining of the gastric biopsy specimen.All H.pylori positive patients received standard triple therapy for 14 d and were subjected for repeat endoscopy at 6 wk.Patients who continued to be positive for H.pylori on second endoscopyreceived second line salvage therapy.All the patients were assessed for platelet response at 6 wk,3rd and 6th months.RESULTS:Of the 36 patients,17 were positive for H.pylori infection and eradication was achieved in16 patients.The mean baseline platelet count in the eradicated patients was 88615.38±30117.93/mm3and platelet count after eradication at 6 wk,3 mo and6 mo was 143230.77±52437.51/mm3(P=0.003),152562.50±52892.3/mm3(P=0.0001),150187.50±41796.68/mm3(P=0.0001)respectively and in the negative patients,the mean baseline count was71000.00±33216.46/mm3 and at 6 wk,3rd and 6th month follow up was 137631.58±74364.13/mm3(P=0.001),125578.95±71472.1/mm3(P=0.005),77210.53±56892.28/mm3(P=0.684)respectively.CONCLUSION:Eradication of H.pylori leads to increase in platelet counts in patients with cITP and can be recommended as a complementary treatment with conventional therapy.     

Helicobacter pylori infection and the prevalence of hypertension in Chinese adults: The Dongfeng‐Tongji cohort

Although many studies explored the association between helicobacter pylori (H pylori) infection and hypertension, there is no consensus. This study is to investigate the association between H pylori infection and the prevalence of hypertension among a middle‐ and old‐age Chinese population. A cross‐sectional study including 17,100 participants from the Dongfeng‐Tongji cohort study was performed. All participants underwent a ¹⁴C‐urea breath test and a routine health check‐up. Logistics and linear regression with multivariable adjustment were used to quest the association between H pylori infection and hypertension. The individuals with H pylori infection had a higher prevalence of hypertension (57.5% vs 55.1%, P = .002), and infection rate of H pylori in patients with hypertension is higher than that in non‐hypertensive individuals (48.8% vs 46.4%, P = .002). After adjustment for potential confounders, H pylori infection increased the prevalence of hypertension (odds ratio, 1.117, 95% confidence interval (CI), 1.029‐1.213, P = .008). Moreover, compared with participants without H pylori infection, individuals infected had an increase of 0.905 mm Hg (95% CI, 0.025‐1.785, P = .044) for diastolic blood pressure. However, there was no interaction between H pylori infection and traditional risk factors on hypertension. These findings suggested that H pylori infection was positively associated with the prevalence of hypertension.     

Rapid recovery of platelet count following administration of liposome-encapsulated clodronate in a mouse model of immune thrombocytopenia

Immune thrombocytopenic purpura (ITP) is a haematological disorder characterized by increased platelet consumption. The destruction of platelets is mediated by the reticulo-endothelial system (RES), particularly by splenic and hepatic macrophages. Previously, we demonstrated in a mouse model of thrombocytopenia that the depletion of these cells by liposome-encapsulated clodronate (LIP-CLOD) induces the recovery of the platelet count. We now report that LIP-CLOD is capable of reversing the thrombocytopenia with minimal effects on both, functional RES integrity and platelet functionality. Our data indicate that thrombocytopenic mice treated with low doses of LIP-CLOD/body weight increase the platelet count to haemostatically safe values within 18 h of treatment. The predictable bleeding time was significantly decreased in these mice, suggesting that the circulating platelets have enhanced haemostatic capacity. Platelet functionality measured through the ADP-induced fibrinogen-binding assay showed normal platelet activation after treatment. Regarding immunological competence, mice treated with LIP-CLOD showed similar antibody titres against sheep red blood cells. However, antibody-dependent cell-mediated cytotoxicity carried out by splenocytes was reduced. All these data demonstrate that LIP-CLOD deserves consideration as a potential therapeutic approach in thrombocytopenic states in which the rapid increase of platelet count is the primary goal.     

Procoagulant profile in patients with immune thrombocytopenia

Despite their low platelet count some immune thrombocytopenia (ITP) patients seldom bleed, indicating the presence of factors to compensate thrombocytopenia. Moreover, ITP patients may have an increased risk for thrombosis. These facts suggest the presence of procoagulant mechanisms that have not been clarified yet. The aim of this study was to identify these possible factors. Moreover, the utility of rotational thromboelastometry (ROTEM^®) to test haemostasis in these patients was also evaluated. Patients with ITP presented a procoagulant profile due to an increased amount of platelet‐ and red cell‐microparticles, an increased resistance to protein C and the formation of a clot more resistant to fibrinolysis due to augmented levels of plasminogen activator inhibitor‐1, which might reflect an endothelial damage/activation in ITP patients. Despite increased maximum clot firmness and reduced lysis, ROTEM^® profiles showed a prolonged clotting time that might rely on the presence of anti‐platelet antibodies as suggested by the increased lagtime in thrombin generation test caused by plasma from ITP patients on platelets from healthy controls. These results indicate the need to individualize therapeutic treatment for ITP patients, considering their procoagulant profile and the presence of concomitant risk factors. Moreover, ROTEM^® appeared to be useful for evaluating haemostasis in ITP patients.     

Platelet recovery in patients with idiopathic thrombocytopenic purpura after eradication of Helicobacter pylori

The relationship between Helicobacter pylori infection and idiopathic thrombocytopenic purpura (ITP) has been investigated in several studies. We investigated the prevalence of H. pylori infection and the clinical effects of eradication in 22 Japanese patients with chronic ITP. H. pylori infection was found in 14 (63.6%) of the patients by histologic and culture examinations of biopsy samples obtained by gastrointestinal endoscopy. H. pylori was eradicated by proton pump inhibitors and 2 kinds of antibiotics in 13 (92.9%) of the 14 patients in whom the results of treatment could be evaluated. Five (38.4%) of those 13 patients had platelet recovery (platelet count of more than 100 x 10(9)/L and an increase of more than 30 x 10(9)/L with respect to the baseline value) after eradication. The median follow-up period was 15 months. One patient who had a complete response had a partial relapse after cessation of prednisolone treatment without any evidence of H. pylori reinfection. Another patient, in whom H. pylori was not eradicated even after 2 treatment sessions, had a partial response after treatment. A screening examination for H. pylori infection may be necessary for Japanese patients with newly diagnosed ITP. Although the exact mechanism underlying platelet recovery after H. pylori eradication is not clear, the results of this study indicated that H. pylori eradication treatment is a good option for some patients with chronic ITP.     

Absence of platelet response after eradication of Helicobacter pylori infection in patients with chronic idiopathic thrombocytopenic purpura

Eradication of Helicobacter pylori infection has been associated with the correction of thrombocytopenia in patients with idiopathic thrombocytopenic purpura (ITP). We have analysed the response to eradication of H. pylori in a series of 56 adult patients with chronic ITP. Forty patients had H. pylori infection (71%) that was eradicated in 23 of 32 evaluable patients (72%). Platelet counts did not significantly vary according to H. pylori treatment outcome. Three of 56 patients (5%) achieved a partial response attributable to H. pylori eradication. Therefore, detection of H. pylori infection should not be routinely included in the initial work-up of ITP.     

Beyond the platelet count: immature platelet fraction and thromboelastometry correlate with bleeding in patients with immune thrombocytopenia

Platelet counts (PC) estimate bleeding risk in Immune Thrombocytopenia (ITP). We investigated whether measures of thromboelastometry and absolute immature platelet fraction (A‐IPF) would correlate better with acute bleeding score (ABS) than PC or mean platelet volume (MPV). Simultaneous determination of ABS, complete blood count and thromboelastometry was performed in 141 ITP patients; 112 underwent A‐IPF testing. Subgroup analyses were performed for paediatric subjects, PC <60 × 10⁹/l and <30 × 10⁹/l. PC significantly inversely correlated with ABS in all subjects, PC <30 × 10⁹/l and total paediatric cohort. MPV did not correlate with ABS in any subgroup. Thromboelastometry measures of clot firmness, but not PC, significantly correlated with ABS in all subjects with PC <60 × 10⁹/l, and children with PC <60 × 10⁹/l and <30 × 10⁹/l. A‐IPF demonstrated stronger correlation with ABS than did PC among all subjects, those with PC <60 × 10⁹/l, all children and children with PC <30 × 10⁹/l (r = ?0·37; r = ?0·34; r = ?0·44; r = ?0·60) versus ABS with PC (r = ?0·36; ns; r = ?0·32; ns). Stronger correlations of both thromboelastometry measures of clot firmness and A‐IPF than PC with ABS suggest factors beyond PC, i.e. related to platelet function, contribute to ITP bleeding pathophysiology. Thromboelastometry, A‐IPF and ABS can be incorporated into routine or acute visits.     

Detection of platelet autoantibodies to identify immune thrombocytopenia: state of the art

Immune Thrombocytopenia (ITP) is diagnosed by exclusion of other causes for thrombocytopenia. Reliable detection of platelet autoantibodies would support the clinical diagnosis of ITP and prevent misdiagnosis. We optimized our diagnostic algorithm for suspected ITP using the direct monoclonal antibody immobilization of platelet antigens assay (MAIPA), which evaluates the presence of platelet autoantibodies on the glycoproteins (GP) IIb/IIIa, Ib/IX and V bound on the patient platelets. The direct MAIPA was shown to be a valuable technique for the detection of platelet autoantibodies and could possibly become a guide for optimizing therapy towards a more personalized treatment of ITP.     

Romiplostim therapy in children with unresponsive chronic immune thrombocytopenia

Romiplostim, a thrombopoiesis-stimulating peptibody, represents a new therapeutic option in adult refractory chronic immune thrombocytopenia (ITP). This study aimed to assess the short-term efficacy and safety of romiplostim in children with chronic ITP. Eight non-splenectomized patients with chronic ITP refractory to standard lines of medical therapy were recruited from the Pediatric Hematology Unit, Children's Hospital, Ain Shams University, Cairo, Egypt. One patient was initially excluded because of increased bone marrow reticulin (grade 3). Therapy was initiated in seven patients, aged 3.4–15.2 years (median 5.5 years), and the disease duration ranged from 13 months to 7.3 years (median 2.4 years); none were splenectomized. Romiplostim dose was started as 1?µgm/kg/week and the dose escalated by 1?µgm/kg/week according to platelet count. The duration of therapy varied between 1 and 22 weeks (median 12 weeks). Results revealed that four out of the seven patients achieved variable response. Four patients demonstrated rapid increase in platelet count when pulse steroid therapy was added. Most reported adverse events were mild and transient. This case series study reveals variable response rate in children with chronic ITP to romiplostim therapy; addition of steroids especially in emergency bleeding situations could potentiate romiplostim thrombopoietic effect even in patients initially refractory to steroids. Romiplostim safety and efficacy in pediatric ITP needs further long-term studies.