Evaluation of clinical and laboratory findings with JAK2 V617F mutation as an independent variable in essential thrombocytosis

Secondary thrombocythemia with ST-segment elevation myocardial infarction as the first manifestation: a case report

Secondary thrombocythemia (ST), also called reactive thrombocytosis, is caused by a disorder that triggers increased production by normal platelet-forming cells and is characterized by the abnormally increased number of platelet and megakaryocytes in the bone marrow. Previous reports have found complications from malignant tumors, chronic inflammation, acute inflammation, acute hemorrhage, splenectomy, etc. to be the common causes of ST. However, reports of secondary thrombocytosis caused by antibiotics are limited and there are no reports of secondary thrombocytosis with acute myocardial infarction as the first presentation. If the patient is at high risk of thrombosis, intensive antithrombotic therapy is required. To raise clinicians' awareness of drug-induced secondary thrombocytosis and to enhance antithrombotic therapy for high-risk patients, this article presented a case of drug-induced secondary thrombocytosis with acute ST-segment elevation myocardial infarction as the primary manifestation.

CASE PRESENTATION

An 80-year-old woman was admitted with cardiogenic shock due to post-activity chest pain. She was started on aspirin and clopidogrel antiplatelet therapy, then replaced aspirin with indolibuprofen, which has relatively few side effects. There was no significant decrease in platelet counts during treatment.

CLINICAL DISCUSSION

Secondary thrombocythemia, characterized by nonspecific symptoms, is difficult to diagnose. Secondary thrombocytosis with acute myocardial infarction as the first symptom is uncommon, but is very urgent and associated with a poor prognosis. What's more, cause-specific treatment counts for secondary thrombocythemia. Therefore it is important to search for the causal factor of secondary thrombocytosis. Secondary thrombocytosis caused by cephalosporins is rare. There is a need to arouse the attention of clinicians to the ST caused by cephalosporins and to provide a guide of treatment to these patients.

CONCLUSION

After a thorough analysis of the pertinent literature, we discovered that several retrospective studies demonstrated the effectiveness of cytoreductive therapy in significantly reducing platelet counts. Based on this finding, we prescribed hydroxyurea to our patient, which led to a gradual decrease in platelet count and ultimately resulted in a return to normal levels.

P, Ahuja A, Somasundarum V, Mishra K, Chatterjee T. Correlation of Thrombosis and Clinicohematological Parameters with JAK2V617F Mutation in Philadelphia-Negative CMPNs: A Study from India

Objective Philadelphia-negative chronic myeloproliferative neoplasms (CMPNs), which include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), are characterized by the presence of JAK2V617F (exon 14) mutation, and this occurs in 90 to 95% cases of PV and 50 to 60% cases of ET and PMF. Still, this is a matter of debate regarding the correlation of this mutation with thrombosis and clinicohematological parameters in CMPNs. So, we conducted this study to ascertain the association of JAK2V617F mutation with thrombotic complications and clinicohematological parameters of these patients.

Materials and Methods This prospective and retrospective study was conducted during 2018 to 2019 at the Department of Laboratory Sciences and Molecular Medicine of a tertiary care hospital, and 160 CMPN patients were enrolled. Complete hemogram was done and DNA was extracted, followed by real-time qualitative polymerase chain reaction to check for JAK2V617F mutation. This mutation was then correlated with complications, mainly thrombosis, hematological parameters, and clinical parameters such as age and splenomegaly.

Results Among 160 CMPN patients, 60 were females and 100 were males, with male to female ratio of 1:0.6, and age range of 27 to 85 years. Total 91 (56.9%) patients were JAK2V617F positive and the remaining 69 (43.1%) were negative for this mutation. We observed statistically significant correlation of leukocyte count, splenomegaly, and thrombosis in JAK2V617F-mutated patients as compared to unmutated patients.

Conclusion This study emphasizes the importance of JAK2V617F mutation in CMPNs and stresses on its association with clinical, hematological phenotype, and thrombotic complications, which may open new horizons in prognostication and management protocol.

Evaluation of trace elements in essential thrombocytosis and reactive thrombocytosis

BACKGROUND

Trace elements (TE) are vital for cellular mechanisms at biological, chemical and molecular levels. The effects of TE in diagnosis, progression and treatment of essential thrombocytosis (ET), which is one of the chronic myeloproliferative neoplasms is a rare clonal stem cell disease characterized by increased thrombocyte numbers with impaired function, have not been elucidated in detail yet. The aim of the present study was to investigate the effects of TE alterations in an ET model and the efficacy of TE in ET treatment protocol by means of a vast number of TE.

METHODS

Study groups were categorized as patients with ET diagnosis (ET group, n:30), patients with reactive thrombocytosis secondary to iron deficiency anemia (IDA-RT) (IDA-RT group, n:30) and healthy controls (HC group, n:30). Serum levels of copper (Cu), iron (Fe), cobalt (Co), chromium (Cr), aluminum (Al), silicon (Si), nickel (Ni), zinc (Zn), selenium (Se), manganese (Mn), boron (B) and magnesium (Mg) were analyzed utilizing inductively coupled plasma-optical emission spectrophotometer instrument (ICP-OES). Statistical analysis was evaluated using SPSS 23.0.

RESULTS

ET group had statistically higher serum levels of Co and Mg (p < 0.05), Ni and Mn (p < 0.001), and lower Si (p < 0.05) than IDA-RT group. ET group had statistically higher serum levels of Co and Mn (p < 0.05), and Ni (p < 0.001), and lower Al, Si and Se (p < 0.001) than HC group. Serum levels of Fe, Al and Se (p < 0.001), and Mg (p < 0.01), and Zn (p < 0.05) in IDA-RT group were significantly lower than HC group.

CONCLUSION

This novel study pointed out that alterations of many serum TE by means of both increment or decrement might have close relationship with mechanisms and complications of ET onset and follow-up. We consider that further research of TE would elucidate ethiopathogenesis and prognosis of ET. Thus, analysis of serum trace elements in essential thrombocytosis patients may be an important protocol by means of diagnosis, treatment and follow-up intervals.

Determination of cerebral blood flow velocity and microembolic signals in essential thrombocytosis by transcranial doppler ultrasonography

OBJECTIVES

The goal of treatment in essential thrombocytosis (ET) is to prevent vascular complications such as thrombosis and hemorrhage. This study aimed to evaluate the risk of cerebrovascular microembolism in ET patients due to detection of microembolic signals (MES) and measure cerebral blood flow velocity (CBFV) by Transcranial Doppler (TCD) ultrasonography.

MATERIAL AND METHODS

In this prospective case-control study, forty patients with diagnosed ET and age and sex-matched forty healthy controls were examined by the TCD sonography.

RESULTS

The ET group had a higher rate of MES (8/40) in the right MCA than that in the control group (none), as measured by TCD. Five patients had MES at the left MCA compared to that in no subjects in the control group. The comparison of the ET and control groups in terms of CBFV parameters showed significantly lower end-diastolic FV at the right MCA in the ET group compared to that in the control group (p < 0.05). On the other hand; both pulsatility and resistance indices in the right and left MCA and the ratios of systolic to diastolic blood flow rates in the right and left MCA were significantly higher in the ET group than that in the control group.

DISCUSSION

This study revealed that MES seems to be more common in patients with ET despite treatment. We could suggest that ET patients should be monitored more closely to address the potential risk of developing a cerebrovascular disease, which can be estimated by detection MES and raised CBFV, combine antiplatelet therapies to standard treatments.

Somatic Mutations in Philadelphia Chromosome-Negative Myeloproliferative Neoplasms

Myeloproliferative neoplasms (MPN) include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). MPN are characterized by clonal proliferation of myeloid progenitors leading to erythrocytosis, thrombocytosis, or leukocytosis, and risk of hemorrhagic and thrombotic events, as well as myelofibrosis and blast transformation. The discovery of somatic mutations in MPN, namely JAK2 V617F, JAK2 exon 12, MPL, and CALR mutations, has permitted a more specific approach to diagnosis and treatment. The prevalence of JAK2 V617F mutations is higher than 95% in PV, 50%-75% in ET and 40%-75% in PMF. JAK2 exon 12 mutations are specific of PV. A 20%-30% of patients with ET and PMF present a CALR mutation. The screening of mutations strengthens the diagnosis of MPN since 97% of MPN have at least 1 somatic mutation. Interestingly, different mutations grant different phenotype and prognosis. Of particular importance, CALR mutations grant a favorable prognosis in ET and PMF, while ASXL1 mutations confer a poorer outcome. In fact, the use of CALR/ASXL1 status for the prognostication of patients has increased clinical value and is now suggested for guidance of therapy in PMF. The increasing importance of mutations in the management of MPN warrants a more frequent revision of current diagnostic criteria and prognostic models and a better understanding of the mechanisms leading to MPN subset differentiation.

Increased mean platelet volume (MPV) is an independent predictor of inferior survival in patients with primary and secondary myelofibrosis

Neoplastic megakaryopoiesis is a dominant feature of Philadelphia-chromosome-negative myeloproliferative neoplasms (Ph- MPNs), and elevated mean-platelet-volume (MPV) is a common finding in these diseases. The clinical and prognostic significances of MPV in patients with primary (PMF) and secondary myelofibrosis (SMF) have not been reported. We retrospectively analyzed 87 patients with myelofibrosis (66 with PMF, 21 with SMF) treated at our institution. MPV was recorded in addition to other hematological and clinical parameters. MPV was elevated in both PMF and SMF patients in comparison to controls, whereas there was no statistically significant difference between PMF and SMF. Elevated MPV was associated with lower platelets (P = 0.016), higher white blood cells (P = 0.015), higher percentage of circulatory blasts (P = 0.009), higher lactate dehydrogenase (P = 0.011), larger spleen size (P = 0.014) and higher Dynamic International Prognostic score category (P = 0.027), while there was no statistically significant association with driver mutations or degree of bone marrow fibrosis. Higher MPV was univariately associated with inferior overall survival in the whole cohort (HR = 3.82, P = 0.006), PMF (HR = 4.35, P = 0.007) and SMF patients (HR = 7.22, P = 0.034). These associations remained significant in multivariate analyses adjusted for DIPSS. Higher MPV is associated with more aggressive disease features and exhibits powerful independent prognostic properties in both PMF and SMF settings.

Role of JAK2 V617F mutation and aberrant expression of microRNA-143 in myeloproliferative neoplasms

BACKGROUND

Myeloproliferative neoplasms (MPNs) are clonal myeloid disorders characterized by the overproduction of mature blood cells. The pathogenetic hallmark of MPNs is the dysregulation of JAK-STAT signaling, usually associated with the JAK2 V617F mutation. Multiple additional genetic and epigenetic alterations that constitutively activate the JAK-STAT signaling pathway have been described, including the modulation of the microRNAs (miRs) expression levels. The aims of our study were to investigate JAK2 V617F mutation allele burden and miR-143 expression levels in MPNs patients and to investigate the correlation between these genetic signatures and hematological parameters.

METHODS

In total 78 patients with a clinical diagnosis of polycythemia vera (PV), essential thrombocythemia (ET) and idiopathic myelofibrosis (IM), made according to the WHO 2008 criteria, were included in the study. Twenty healthy subjects were checked as controls. Quantification of JAK2 V617F mutation and miR-143 expression levels were determined by real-time quantitative polymerase chain reaction.

RESULTS

The miR-143 expression in MPNs patients was 2.97-fold higher than in controls. JAK2 V617F mutation allele burden and miR-143 expression level resulted higher in PV and IM respect to ET patients. Patients who had V617F allele burden >50% displayed a higher miRNA-143 expression level than patients with allele burden <50%. In MPNs patients, a statistically significant positive correlation was observed between JAK2 V617F mutation allele burden and hemoglobin and hematocrit values and between miR-143 expression levels and platelet count.

CONCLUSIONS

Our findings of aberrant miR-143 expression support the concept that factors other than JAK2 V617F mutation may contribute to the pathogenesis and some clinical signs of MPNs.

The impact of JAK2V617F mutation on different types of thrombosis risk in patients with essential thrombocythemia: a meta-analysis

To assess the effect of JAK2V617F on different thrombotic risks in essential thrombocythemia (ET) patients, we identified eligible studies from several databases including Pubmed, Embase, and Cochrane Central Register of Controlled Trials (up to November 2014). Twenty-two studies of 2922 ET patients were included in exploring the relationship between JAK2V617F and the risk of thrombosis. Compared to JAK2V617F-negative ET patients, JAK2V617F-positive ET patients had higher odd risks (ORs) of arterial thrombosis [OR = 2.59 (1.84-3.65)] and venous thrombosis [OR = 2.10 (1.53-2.88)]. The JAK2V617F-positive group was also more prone to increased risk of microcirculatory disturbances [OR = 1.50 (0.97-2.32)]. Moreover, JAK2V617F may indicate increased risk of either arterial [OR = 1.71 (1.22-2.39)] or venous thrombosis [OR = 2.90 (1.54-5.46)] before diagnosis of ET. During follow-up, JAK2V617F might not be related to arterial thrombosis [OR = 1.90 (0.90-2.08)], but rather venous thrombosis [OR = 1.95 (1.08-3.53)]. In conclusion, JAK2V617F increased the risk of arterial and venous thrombosis in ET patients, while understanding its role in microcirculatory disturbances will require further studies.