Current Understanding of Immune Thrombocytopenia: A Review of Pathogenesis and Treatment Options

The management of immune thrombocytopenia (ITP) and the prediction of patient response to therapy still represent a significant and constant challenge in hematology. ITP is a heterogeneous disease with an unpredictable evolution. Although the pathogenesis of ITP is currently better known and its etiology has been extensively studied, up to 75% of adult patients with ITP may develop chronicity, which represents a significant burden on patients' quality of life. A major risk of ITP is bleeding, but knowledge on the exact relationship between the degree of thrombocytopenia and bleeding symptoms, especially at a lower platelet count, is lacking. The actual management of ITP is based on immune suppression (corticosteroids and intravenous immunoglobulins), or the use of thrombopoietin receptor agonists (TPO-RAs), rituximab, or spleen tyrosine kinase (Syk) inhibitors. A better understanding of the underlying pathology has facilitated the development of a number of new targeted therapies (Bruton's tyrosine kinase inhibitors, neonatal Fc receptors, strategies targeting B and plasma cells, strategies targeting T cells, complement inhibitors, and newer TPO-RAs for improving megakaryopoiesis), which seem to be highly effective and well tolerated and result in a significant improvement in patients' quality of life. The disadvantage is that there is a lack of knowledge of the predictive factors of response to treatments, which would help in the development of an optimized treatment algorithm for selected patients.

Quantitative analyses of CD7, CD33, CD34, CD56, and CD123 within the FLT3-ITD/NPM1-MUT myeloblastic/monocytic bulk AML blastic populations

The most frequent mutations in acute myeloid leukemia (AML) - FLT3-ITD and NPM1 - are associated with a specific immunophenotype. We evaluated the levels of surface antigens in an uninvestigated AML patient population according to the combination of FLT3-ITD/NPM1 mutations. Antigen levels were calculated as the geometric mean fluorescence index (MFI) ratio between myeloblasts or monoblasts/monocytes and a negative population for the specific antigen. In myeloblastic populations, FLT3-ITD cases presented CD7^high MFI values (p < .001), while NPM1-MUT cases presented CD33^high (p < .001), and CD34^low (p < .001) MFI values. Within the monoblastic/monocytic populations, CD56^high expression was observed only in the FLT3-WT/NPM1-MUT population (p=.003). The single common antigen expression between myeloblasts and monoblasts/monocytes was CD123^high expression only within the FLT3-ITD/NPM1-MUT subgroup. Our results present a subtle influence of FLT3-ITD/NPM1 mutations upon antigen expression profiles in myeloblasts vs monoblasts/monocytes, and we described a novel correlation between the presence of NPM1 and CD56^high values within bulk leukemic monoblasts/monocytes.

FLT3-ITD DNA and mRNA levels in AML do not correlate with CD7, CD33 and CD123 expression

Introduction

FLT3 internal tandem duplication (ITD) mutations are found in around 25% of all acute myeloid leukaemia (AML) cases and is associated with shorter disease‐free and overall survival. Previous reports have shown that FLT3‐ITD induces a specific phenotype in leukemic blasts, which is characterized by high levels of CD33 and CD123, and that expression of CD33 and CD123 is directly influenced by the DNA FLT3‐ITD/wild‐type FLT3 allelic ratio (AR).

Methods

A total of 42 FLT3‐ITD and 104 FLT3‐ITD–negative AML patients were analysed. Immunophenotyping data were used to calculate antigen expression levels as the ratio between the geometric mean fluorescence intensities (MFIs) of leukemic blasts and MFIs of negative lymphocyte populations. FLT3‐ITD‐DNA and RNA analysis was performed, under the same conditions, by capillary electrophoresis.

Results

Compared with the control group, the FLT3‐ITD cohort presented significantly higher CD7, CD33 and CD123 levels. In order to assess the impact of FLT3‐ITD abundance on antigen expression, the patients were grouped for each parameter into two cohorts using the following threshold values: (a) 0.5 for the AR, according to current AML guidelines; (b) 0.7 for the FLT3‐ITD/FLT3‐WT mRNA ratio (RR); and (c) 1.3 for the FLT3‐ITD RR/AR ratio. We found higher values of CD33 for RR/AR ≥1.3, and no other statistical differences between CD7, CD33 and CD123 levels of the other FLT3‐ITD groups. In terms of correlations between MFI values and FLT3‐ITD parameters, we only observed a moderate interdependence between CD33 MFI and the RR/AR ratio, and a weak negative correlation between CD123 MFI and AR.

Conclusion

FLT3‐ITD mutations induce a specific antigen profile in AML blasts, and our data do not onfirm previous reports of FLT3‐ITD AR influencing both CD33 and CD123 expression.

Primary myelofibrosis and pregnancy outcomes after low molecular-weight heparin administration: A case report and literature review

RATIONALE

Primary myelofibrosis is encountered with the myeloproliferative diseases and is the least prevalent among women of childbearing age. The prognosis is guided by pancytopenia, leukemic transformation and thrombosis which are the dominant complications.

PATIENT CONCERNS

Data regarding protocol management during pregnancy in the context of myelofibrosis are insufficient. Fewer than ten cases have been described until now and half of this cases have resulted in fetal death due to placental infarction during the second and third trimesters.

DIAGNOSES

We present the case of a 34-year-old pregnant woman diagnosed with Jak 2- negative primary myelofibrosis. Personal history did not include miscarriage or stillbirth.

INTERVENTIONS

The patient was previously treated with anagrelide hydrochloride, which was interrupted at 6 weeks of gestation when the pregnancy was confirmed. It was replaced with Interferon-a 3 MU/day. Because of severe thrombocytosis, administration of aspirin 150 mg/day was recommended.

OUTCOMES

The pregnancy was uneventful. The patient was hospitalized at 33 weeks of gestation because of moderate vaginal bleeding and high risk of preterm birth. After a specialized hematological investigation, the treatment with aspirin was replaced with low-molecular-weight heparin 0.6 ml per day. This combined treatment assisted in the natural tendency to lower platelet counts during pregnancy and resulted in stabilization of the hematological status. At 38 weeks of gestation the patient delivered a healthy baby boy via cesarean. He weight 2850 grams and his Apgar score was 9. Anticoagulant and interferon treatments were continued post-partum under hematologist surveillance.

LESSONS

This case was rare and complex. Because it was related to pregnancy it required continuos collaboration and supervision between obstetrician and hematologist.

Unique evolution of chronic lymphoproliferative disorders associated with hepatitis B virus infection and viral reactivation – a major concern with multidisciplinary approach

Background. The association of hepatitis B virus (HBV) infection with chronic lymphoproliferative disorders becomes a matter of debate, with multidisciplinary approach due to possible viral reactivation after immuno-chemotherapy. Material and methods. We studied two patient groups with chronic lymphoproliferative disorders, one with HBV infection (HbsAg+ and HbsAg- HbcAb+ HBs+/-) – 43 patients and one without viral infection (104 patients). Clinical and paraclinical parameters, therapy, survival of both groups were compared; the occurrence of viral reactivation was followed. Data were statistically analyzed. Results and discussion. The HBV infection group included HbsAg+-ve patients (72%) and occult HBV infection patients. The median onset age for lymphoproliferative disorders HBV+-ve was significantly younger (55 vs. 61 years, p<0.05). Hepatomegaly and abdominal adenopathies were more frequent in HBV patients (p=0.003, respectively p=0.027). Hepatic function was altered in HBV patients both at disease onset (AST p=0.0213, GGT p=0.0002) and after first line therapy (AST p=0.0003, ALT p=0.019, FA p=0.008, GGT p=0.000, total bilirubine p=0.043, INR p=0.0003 and albumine p=0.05). The risk of hepatic dysfunction after first line therapy is increased 6 times by HBV infection (p=0.0009, OR=6.000, 95%CI: 1.9121-18.8272), which could negatively impact the hematological disease evolution by lowering therapeutic dose, leading to an inferior treatment result. Viral reactivation occurred both in HbsAg+-ve (21.42%) and HbsAg- HbcAb+-ve patients (60%). None of the occult carriers received antiviral prophylaxis. Whithin our occult carrier group, the viral reactivation percentage is high, therefore we would reccomand antiviral prophylaxis. The overall survival was similar in both group of patients. Conclusions. HBV-positive chronic lymphoproliferative disorders could become a new pathological entity, with individual clinical features and outcome and possibly with negative impact on long term survival. Antiviral prophylaxis for occult carriers could significantly reduce the viral reactivation rate and therefore the therapeutic guidelines should be revised.

The evaluation of the outcome in myelodysplastic patients by using non-cytogenetic prognostic scores

Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematopoietic stem cell disorders; they are characterized by ineffective hematopoiesis and a predilection to the development of acute myeloid leukemia (AML). For a rapid evaluation of the outcome in myelodysplastic patients non-cytogenetic prognostic scores can be used.

AIM

This study proposed to demonstrate that age and gender are important factors in the outcome of the patients diagnosed with myelodysplastic syndrome.

MATERIALS AND METHODS

This study was conducted in the Department of Hematology of the Emergency University Hospital Bucharest during October 2008 and October 2012.

RESULTS

Male sex and age higher than 60 years are associated with high risk in the studied cases by using the Spanish prognostic score. According to Goasguen score: male sex and age, patients older than 60 years, present characteristics associated with an intermediate risk. Based on the Dusseldorf score, age over 60 years and female gender were associated with pronounced risk in the examined group. By examining the Bournemouth score in our group, we found that age > 60 years correlated with a higher frequency of risk, but no significant differences regarding the sex of patients were observed.

CONCLUSIONS

We concluded that age > 60 years and male gender are important predisposing factors in the survival.

Sudden blast crisis in a chronic myeloid leukemia patient during imatinib therapy

Imatinib mesilate (IM) is the first line therapy for chronic myeloid leukemia (CML) patients in chronic phase. Although it offers a complete cytogenetic response (CCyR) in a majority of patients, there still are some rare cases in which a sudden blast crisis (SBC) evolves. The mechanism of this unexpected event is not yet completely understood. We present the case of a female patient who developed a SBC while being under IM therapy. We do not know for sure which is the role of IM in this event, but current available data suggest that this drug may have a permissive effect on the evolution of some aggressive subclones in the context of restored normal cell population.

Refractory anemia with ring sideroblasts associated with marked thrombocytosis: case report and literature review

"Refractory anemia with ring sideroblasts and thrombocytosis" (RARS-T) is a rare disease, a provisional entity, with a controversial status in the 2008 revised WHO classification. Even at present time, RARS-T is a matter of debate whether it is a distinct clinicopathological entity or more likely a constellation of clinical and pathological features of two well-defined myeloid neoplasms, myelodysplastic syndrome and myeloproliferative neoplasm. Perhaps none of the clonal disorders illustrates better the challenges presented by the current classification of myeloid neoplasms, than this clinical entity with overlapping features of both refractory anemia with ring sideroblasts and essential thrombocythemia. The purpose of this study is to present the evolution of such a case, with difficulties in establishing not only the correct diagnosis, but also the appropriate therapeutic approach. For this reported case, we present documented details regarding persistent thrombocytosis, slightly increased number of leukocytes and analysis of Janus kinase 2 (JAK2) genes that revealed a V617F mutation, confirming the presence of an underlying myeloproliferative neoplasm, followed later in the evolution by occurrence of myelodysplastic features as ring sideroblasts. This case might interest pathologists, but especially clinicians, for at least two reasons: the rarity of this disease and the lack of data on prognosis of these patients, probably because of relatively recent established diagnosis criteria and existence of few studies with small number of patients. The third interesting aspect for practitioners would be the absence of consensus on optimal clinical treatment for this disorder, because there are few cases that meet the rigorous diagnostic criteria.

Platelet dysfunction in acute leukemias and myelodysplastic syndromes

The hemorrhagic and thrombotic diathesis represents a frequent complication in myelodysplastic syndromes (MDS) and in acute leukemias. They are correlated with the number of the platelets, but also with their qualitative disorders, such as membrane glycoprotein changes. The latter are revealed by many platelet studies including flow-cytometry and comprise modified activation, secretion and aggregation patterns.

Chronic myeloid leukemia--from the National to the European Registry--limited experience of a single center

Chronic myeloid leukemia (CML) is a hematopoietic stem cell disorder in which the diagnosis is confirmed by detection of a genetic marker: Philadelphia (Ph) chromosome in almost 90% of cases. Some of Ph1 negative patients, nevertheless, test positive for the abnormal gene, or the abnormal protein associated with this chromosome, when more sensitive studies, such as PCR or FISH are used and nowadays the diagnosis of CML is based, not only on cytogenetic, but also on molecular analysis. The better understanding of the CML biology provided by the latest researches requires a deeper knowledge about the epidemiologic data in each geographic area, so the compiling of a National and/or European Registry for CML patients, that represents one of the aims of this study, became a stringent matter in our days; it can offer valuable data concerning the real incidence of this disease in Romania and can provide the basics for establishing long-term budgetary strategies.

Preliminary data on the involvement of B, C and D hepatitis viruses in the etiopathogenesis of chronic lymphoproliferative syndromes in Romania

THE AIMS OF THE STUDY: Evaluation of the prevalence of HBV, HCV, HDV infection in patients with chronic lymphoproliferative diseases (CL), identification of the most involved viral genotypes, correlation between viremia dynamics and CL evolution, detection of molecular mechanisms implicated in CL pathogenesis, identification of lymphocytic receptors for viral antigens and biologic markers for early diagnosis of CL.

METHODS

We present preliminary results of the first year of our research grant. This is a prospective, analytic, observational study in patients diagnosed with CL and HBV, HCV, HDV chronic infection. We included the following forms of CL: non-Hodgkin malignant lymphoma (NHL), Hodgkin lymphoma (HL) and chronic lymphocytic leukemia (CLL). We used the following commercial test kits: HCV RNA Real time PCR on a COBAS TaqMan (Roche Diagnostics) analyzer with 28 to 140.000.000 UI/ml detection range for HCV viremia, HBV DNA Real time PCR on a COBAS TaqMan (Roche Diagnostics) analyzer with 6 to 110.000.000 UI/ml detection range for HBV and the Roboscreen-RoboGene AJ kit with 10-10.000.000 replica/ml detection range for HDV.

RESULTS

We have included 20 patients with CL and chronic hepatitis infection so far. Median age of the patients was 61 years. The identified CL forms were: B cell NHL (15 cases), T cell NHL (1 case), CLL (3 cases), Hodgkin lymphoma (1 case), equally distributed in aggressive and indolent forms of CL. HCV infection was diagnosed in 10 patients with CL, HBV infection was found in 10 patients with CL, 3 of them having co-infection HBV + HDV. In 4 patients with HBV infection viremia was over 20.000 IU/ml and the pattern of the CL was the aggressive form of the disease. The feature of the co-infection HBV + HDV was the predominance of indolent forms of CL. Among patients with HCV infection, only 3 cases were detected with viremia over 600.000 IU/ml and CL was represented by aggressive forms of the disease. We also have immunohistochemical data available in 19 cases, which seem to confirm the role of hepatitis viruses in lymphoproliferative disease etiopathogenesis.

CONCLUSIONS

We ascertained an almost equally represented prevalence of HCV and HBV infection in patients with CL. The levels of HBV, HCV and HDV viremia were low in most of the cases. The most frequent form of CL was B cell NHL. We found an equal distribution between indolent and aggressive forms of NHL associated to hepatitis virus infection.

Myeloma cells with asurophilic granules--an unusual morphological variant--case presentation

We present the case of an 80-year-old man who was admitted for anemia, back pain and progressive weakness. After a workup of clinical and laboratory data, the final diagnosis was multiple myeloma. The bone marrow aspirate revealed 53% myeloma cells with peculiar and rare morphological features: numerous large asurophilic--bright red granules--mucopolizaccharides and immunoglobulins secreted and accumulated in the endoplasmic reticulum, typically known as Russel bodies.

An update on the platelet dysfunction in chronic myeloproliferative syndromes

The thrombotic and hemorrhagic diathesis represents a frequent complication in myeloproliferative disorders (CMPD). They are correlated with the number of platelets, but also with their qualitative disorders, such as membrane glycoprotein changes. The latter are revealed by many platelet essays including flow-cytometry and include modified activation, secretion and aggregation patterns. The thrombopoietin platelet receptor (cMPL), affected by the JAK2 V617 mutation encountered in CMPD, may be associated with a prothrombotic status. Its implication reveals the importance of the molecular genetics profile in defining molecular diagnostic hallmarks and makes it a candidate in the early diagnosis of myeloproliferative disorder and a predictor of thrombotic complications in this group of diseases.