Clinical and laboratory characteristics of cyclic thrombocytopenia: an observational study

The highs and lows of cyclic thrombocytopenia

Cyclic thrombocytopenia (CTP) is characterized by periodic platelet oscillation with substantial amplitude. Most CTP cases have a thrombocytopenic background and are often misdiagnosed as immune thrombocytopenia with erratically effective treatment choices. CTP also occurs during hydroxyurea treatment in patients with myeloproliferative diseases. While the aetiology of CTP remains uncertain, here we evaluate historical, theoretical and clinical findings to provide a framework for understanding CTP pathophysiology. CTP retains the intrinsic oscillatory factors defined by the homeostatic regulation of platelet count, presenting as reciprocal platelet/thrombopoietin oscillations and stable oscillation periodicity. Moreover, CTP patients possess pathogenic factors destabilizing the platelet homeostatic system thereby creating opportunities for external perturbations to initiate and sustain the exaggerated platelet oscillations. Beyond humoral and cell-mediated autoimmunity, we propose recently uncovered germline and somatic genetic variants, such as those of MPL, STAT3 or DNMT3A, as pathogenic factors in thrombocytopenia-related CTP. Likewise, the JAK2 V617F or BCR::ABL1 translocation that drives underlying myeloproliferative diseases may also play a pathogenic role in hydroxyurea-induced CTP, where hydroxyurea treatment can serve as both a trigger and a pathogenic factor of platelet oscillation. Elucidating the pathogenic landscape of CTP provides an opportunity for targeted therapeutic approaches in the future.

Cyclic Thrombocytopenia in the Setting of Intracranial Hemorrhage: A Diagnostic and Therapeutic Challenge

Cyclic thrombocytopenia (CTP) as the name suggests presents with cyclic episodes of thrombocytopenia and is frequently initially misdiagnosed as immune thrombocytopenia. Following a lack of sustained response or abnormally increased response to common treatments used for immune thrombocytopenia, a proper diagnosis of CTP can then be made. Prior reports have shown a subset of patients who respond to cyclosporin A. Here, we present a case of CTP that was initially at another facility presumed to have and treated for immune thrombocytopenic purpura. However, after multiple attempts to treat with steroids, intravenous immunoglobulin (IVIG), rituximab, and eltrombopag, episodes of severe thrombocytopenia followed by thrombocytosis continued. The patient ultimately developed intracerebral hemorrhage (ICH) in the setting of one of the episodes of severe thrombocytopenia and developed multiple subsequent complications from which the patient unfortunately did not recover. It was only after developing ICH that the patient had been evaluated at a center with hematology consultation capabilities, at which time after a detailed review of his case and pattern recognition the proper diagnosis of CTP was made with initiation of cyclosporine. This case was further complicated by need to maintain an adequate platelet threshold post-ventriculoperitoneal shunt placement which was necessary due to his ICH and was placed before diagnosis of CTP could be made. While CTP is a rare diagnosis, this case reinforces a greater need to properly diagnose and consider cyclosporine treatment for CTP, as it has been effective in some patients and may help to prevent patient morbidity and especially catastrophic bleeding complications.

Longitudinal study of 2 patients with cyclic thrombocytopenia, STAT3 and MPL mutations

Cyclic thrombocytopenia (CTP) is a rare disease of periodic platelet count oscillations. The pathogenesis of CTP remains elusive. To study the underlying pathophysiology and genetic and cellular associations with CTP, we applied systems biology approaches to 2 patients with stable platelet cycling and reciprocal thrombopoietin (TPO) cycling at multiple time points through 2 cycles. Blood transcriptome analysis revealed cycling of platelet-specific genes, which are in parallel with and precede platelet count oscillation, indicating that cyclical platelet production leads platelet count cycling in both patients. Additionally, neutrophil and erythrocyte-specific genes also showed fluctuations correlating with platelet count changes, consistent with TPO effects on hematopoietic progenitors. Moreover, we found novel genetic associations with CTP. One patient had a novel germline heterozygous loss-of-function (LOF) thrombopoietin receptor (MPL) c.1210G>A mutation, and both had pathogenic somatic gain-of-function (GOF) variants in signal transducer and activator of transcription 3 (STAT3). In addition, both patients had clonal T-cell populations that remained stable throughout platelet count cycles. These mutations and clonal T cells may potentially involve in the pathogenic baseline in these patients, rendering exaggerated persistent thrombopoiesis oscillations of their intrinsic rhythm upon homeostatic perturbations. This work provides new insights into the pathophysiology of CTP and possible therapies.

Cyclical Thrombocytopenia Synchronized With the Patient's Menstrual Cycle Treated With Danazol

Cyclical thrombocytopenia (CTP) is a very rare condition and often misdiagnosed as immune thrombocytopenia (ITP) due to similar features existing between the two. When evaluating a patient for the possible diagnosis of ITP, CTP must be high on the differential diagnosis. The main difference between the two conditions is that CTP is usually unresponsive to the treatment given to ITP and will ultimately display a cyclical nature with periods of low, normal and elevated platelets. As of date, there are only 70 cases in the literature. However, this number may be misrepresented due to the difficulty in diagnosis. The authors report a case of a 36-year-old woman who was misdiagnosed with ITP and underwent unnecessary treatment with corticosteroids, rituximab, intravenous immunoglobulins, and a splenectomy. A diagnosis of CTP was made after extensive review and the authors aim to bring awareness of this uncommon condition.

Cyclic Thrombocytopenia: A Rare Cause of Recurrent Thrombocytopenia

Cyclic thrombocytopenia (CTP) is a very rare hematological disorder that is characterized by periodic fluctuations in platelet counts. Diagnosis is generally delayed due to its similarity with immune thrombocytopenia (ITP). The pathophysiology is unknown and there are currently no guidelines for management. Many patients are usually treated for ITP initially prior to diagnosis. We describe a 67-year-old female with a history of multiple episodes of transient thrombocytopenia who presented to the hospital with another episode of thrombocytopenia. Her workup including HIV, hepatitis screening, vitamin B12, and folate was negative. She received a unit of platelet transfusion and was later observed in the hospital. Further review of her chart showed similar episodes in the past with spontaneous improvement. She was diagnosed with CTP. Her platelet count improved remarkably prior to discharge. In patients with recurrent fluctuation in their platelet count, CTP should be one of the differentials as this might prevent further unnecessary therapies.

Cyclical haematological changes in a case of hypopituitarism

A 40-year-old woman presented to our emergency department in an altered state following a generalised tonic-clonic seizure. On regaining consciousness, she gave a history of bleeding tendencies and menorrhagia, fatigue, nausea, vomiting and appetite loss for a long time. She had received multiple blood transfusions in the last 10 years. Investigations revealed severe hyponatraemia, transaminitis and pancytopenia, which showed cyclical fluctuations in the hospital. Hyponatraemia was attributed to a central cause owing to secondary hypothyroidism and hypocortisolism on evaluation. A diagnosis of cyclical thrombocytopenia was made by logging the trends of blood cell lines and applying the Lomb-Scargle test. Liver biopsy showed features of transfusion hemosiderosis explaining transaminitis. All of the haematological abnormalities and clinical symptoms resolved on thyroxine and corticosteroid replacement, suggesting causal association hypopituitarism with cyclical thrombocytopenia.

How I manage cyclic thrombocytopenia

Cyclic thrombocytopenia (CTP) is a rare disease, which is characterized by periodic fluctuation of the platelet count. The pathogenesis of CTP is unknown and most likely heterogeneous. Patients with CTP are almost always misdiagnosed as having primary immune thrombocytopenia (ITP). The interval between ITP and CTP diagnosis can be many years. CTP patients often receive ITP-specific therapies including corticosteroids, thrombopoietin receptor agonists, rituximab, and splenectomy, which are followed by a transient increase in platelet count that is wrongly attributed to treatment effect with inevitable "relapse." CTP can be diagnosed by frequent platelet count monitoring, which reveals a typical pattern of periodic platelet cycling. An early diagnosis of CTP will prevent these patients from being exposed to possibly harmful therapies. The bleeding phenotype is usually mild and consists of mucocutaneous bleeding at the time when the platelet count is at its nadir. Severe bleeding from other sites can occur but is rare. Some patients respond to cyclosporine A or to danazol, but most patients do not respond to any therapy. CTP can be associated with hematological malignancies or disorders of the thyroid gland. Nevertheless, spontaneous remissions can occur, even after many years.