OBJECTIVE: To investigate inflammation indices and erythropoietin levels for their potential role in distinguishing polycythemia vera from secondary polycythemia and to compare different parameter combinations in terms of the diagnostic accuracy.
METHODS: This retrospective cohort was created from patients assessed for polycythemia from January 2020 to December 2023. Polycythemia vera diagnosis was made according to the 2016 World Health Organization criteria (n = 145). Those who did not fulfill the criteria were defined as having secondary polycythemia (n = 84).
RESULTS: The neutrophil lymphocyte ratio, platelet lymphocyte ratio and systemic immune-inflammation index were significantly higher in the polycythemia vera group (p < 0.001 for all). Erythropoietin had the highest area under the curve in the analysis to distinguish groups, followed by the systemic immune-inflammation index. The platelet lymphocyte ratio (≥135) had the highest specificity to detect polycythemia vera, followed closely by the systemic immune-inflammation index. The sensitivity for polycythemia vera detection was highest with the erythropoietin and systemic immune-inflammation index combination, followed by erythropoietin and the neutrophil lymphocyte ratio. All the single and combinatory variables exhibited significant performance in predicting polycythemia vera after adjusting for age and sex. However, the erythropoietin and systemic immune-inflammation index combination had the highest odds ratio, followed by erythropoietin alone.
CONCLUSIONS: These are promising findings supporting the usability of these biomarkers, especially the systemic immune-inflammation index, as minor criteria in the diagnosis of polycythemia vera. It is especially crucial to note that using erythropoietin in combination with these markers may improve diagnostic accuracy.

Myomatous erythrocytosis syndrome is a rare phenomenon of secondary polycythemia evolving from uterine leiomyoma. Although the underlying pathology is still unknown, patients have an increased risk of venous thrombosis. A 44-year-old GO (gravida zero) presented with an incidental finding of secondary polycythemia, and a diagnosis of myomatous erythrocytosis syndrome was made because of her large uterine fibroids. She was placed on therapeutic anticoagulation after developing pulmonary embolisms and a dural sinus venous thrombosis. Subsequently, she underwent uterine artery embolization, which resulted in a substantial decrease in her erythropoietin (8.1 mU/mL) along with hemoglobin (15.1 g/dL) and hematocrit (4 5g/dL). Myomatous erythrocytosis syndrome can cause venous thrombosis, leading to neurologic complications. In patients with increased risk for surgery, uterine artery embolization is an effective option for treatment.

Continuously holding its position as the sixth most common cause of cancer and the third leading cause of cancer death, globally, Hepatocellular Carcinoma (HCC) remains as a healthcare priority. Production of various substances may result into systemic or metabolic complications, often known as paraneoplastic phenomena of HCC. A 56-year-old male with history of untreated chronic hepatitis B arrived with generalized weakness and intermittent headache in the last two days prior to admission. Laboratory findings demonstrated elevated hemoglobin (20.5 g/dl), alpha-fetoprotein (29,845 ng/dl), and d-Dimer (2,120 ng/ml) levels. Hypoglycemia (44 mg/dl) was documented with normal basal insulin level, confirming non-islet cell tumor hypoglycemia. Abdominal multiphasic CT-scan demonstrated a large solid lesion involving the whole right liver lobe, hyper-enhanced at arterial phase and wash-out pattern at venous and delayed phases, with portal vein thrombosis; thus, confirming HCC BCLC C. Further examinations revealed hypercellularity from bone marrow biopsy with the absence of JAK2 mutation. He underwent serial phlebotomy and received 80 mg acetylsalicylic acid orally, as well as cytoreductive agent to reduce the risk of thrombosis. Despite applications of different interventions, control of hypoglycemia could not be achieved without parenteral administration of high dextrose load. He was planned to receive oral multikinase inhibitor, however, he passed away due to severe hospital-acquired pneumonia. Paraneoplastic phenomena are common in HCC. Increased risk of blood hyper-viscosity and thrombosis attributed to polycythemia, as well as medical emergency resulting from hypoglycemia showed that both conditions should not be overlooked since they may worsen the patient\'s prognosis.

Secondary polycythemia is commonly observed among patients with chronic pulmonary diseases. However, its significance in the context of Coronavirus disease 2019 (COVID-19) is unknown. We retrospectively evaluated a total of 5872 hospitalized COVID-19 patients with mostly severe and critical symptoms, and without prior or subsequently diagnosed myeloproliferative neoplasm. Patients were stratified based on admission hemoglobin into four subgroups: anemia (hemoglobin <120 g/L for females and 130 g/L for males), normal hemoglobin, mild (hemoglobin 160-165 g/L for females and 165-185 g/L for males) and severe polycythemia (hemoglobin >165 g/L for females and >185 g/L for males). Among 5872 patients, a total of 158 (2.7%) had mild and 25 (0.4%) severe polycythemia. Polycythemia was significantly associated with higher respiratory and functional impairment, reduced plasma volume, higher serum osmolarity and comorbidity burden specific to the degree of polycythemia. Patients presenting with mild (odds ratio (OR) = 1.63, p = .003) and severe polycythemia (OR = 4.98, p < .001) had increased risk of death in comparison to patients with normal hemoglobin, whereas no significant associations with venous thromboembolism, arterial thrombosis nor major bleeding were observed. Anemia was associated with higher risk of death (OR = 1.42, p < .001), venous thromboembolism (OR = 1.34, p < .006) and major bleeding (OR = 2.27, p < .001) in comparison to normal hemoglobin. Associations of polycythemia and anemia with mortality diminished, and anemia with venous thromboembolism and major bleeding persisted, after multivariate adjustments for age, sex, comorbidities, COVID-19 severity and functional status. Secondary polycythemia in hospitalized COVID-19 patients without prior of subsequently diagnosed myeloproliferative neoplasm is rare and is associated with high mortality, increasing with degree of polycythemia, but not markedly higher thrombotic risk.

UNASSIGNED: Polycythemia vera (PV) is one of the myeloproliferative neoplasms (MPN) diagnosed by World Health Organization (WHO) criteria 2016, which requires the presence of 3 major criteria: high hemoglobin/hematocrit, bone marrow findings, and Janus Kinase 2 (JAK2) mutation or two major and one minor criteria, including erythropoietin (EPO) level. However, in clinical practice, difficulties in diagnosis can arise as it may be masked by secondary causes for erythrocytosis such as smoking or obstructive sleep apnea (OSA).
UNASSIGNED: Here, we report a 55-year-old gentleman, morbidly obese with OSA on home continuous positive airway pressure (CPAP) machine, who was incidentally found to have polycythemia. Further evaluation confirmed the diagnosis of PV.
UNASSIGNED: PV can be masked by the assumption of secondary polycythemia based on history. This underscores the importance of screening such cohort through JAK2 and EPO testing to avoid missing PV.

UNASSIGNED: Tetralogy of Fallot is a cyanotic congenital heart disease which if untreated leads to death by adulthood. In rare cases who survive this can lead to secondary polycythemia due to chronic hypoxia who can present with multiple indistinct symptoms leading to diagnostic dilemma.
UNASSIGNED: The authors present a rare case of secondary polycythemia diagnosed in early fifties with the unique non-contrast computerized tomography head findings who presented with a spectrum of long standing symptoms and a history of neurological manifestations.
UNASSIGNED: Patients diagnosed with polycythemia in adulthood can have a background of an untreated congenital heart disease, which can be complemented further by appropriate radiological investigations in a resource poor setting.
UNASSIGNED: Polycythemia secondary to an untreated congenital heart disease in the age beyond 50 is a rare occurrence. The presentation of these patients might present clinicians with a diagnostic challenge which can be mitigated with an appropriate knowledge of the peculiar non-contrast computerized tomography head findings.

BACKGROUND: Secondary polycythemia is considered the usual complication of chronic hypoxia. It can theoretically increase the oxygen-carrying capacity, but this adaptive trait has a deleterious effect because the blood viscosity increases, which can induce significant morbidity and mortality, such as stroke and myocardial infarction.
METHODS: A 55-year-old man with a history of a congenitally small main pulmonary artery presented to the emergency department with sustained unsteady walking, dizziness and vertigo. Evaluation revealed elevated hemoglobin and superior posterior circulation cerebral artery thrombosis. The patient was treated with high flux inhalation of oxygen and anti-platelet aggregation.
CONCLUSIONS: The involvement of cerebral vessels has rarely been reported in chronic hypoxia cases. The present case is the first case of superior posterior circulation cerebral artery thrombosis due to chronic hypoxia in a patient with a congenitally small main pulmonary artery. This case demonstrates the importance of recognizing some chronic diseases that can lead to hypoxia and secondary polycythemia thereby leading to hypercoagulable state and subsequent thrombosis.

UNASSIGNED: Several observations have shown that patients with polycythemia have iron deficiency. Our objectives were to report the prevalence of iron deficiency and to evaluate the diagnostic performance of serum ferritin in polycythemia vera.
UNASSIGNED: This is a retrospective descriptive and analytical study carried out in the internal medicine department of the Henri Mondor Hospital, Aurillac, France. The study involved 114 patients with polycythemia, followed in the department from January 1, 2010 to December 31, 2021. To evaluate the diagnostic performance, the JAK2 mutation was considered as the gold standard of diagnosis.
UNASSIGNED: Thirty-three patients had polycythemia vera and 76 patients had secondary polycythemia. The mean age of the patients was 61.79 years (±15.44) with a sex ratio of 4.43. The overall prevalence of iron deficiency was 21.05%. The prevalence was 53% in polycythemia vera group and 1.32% in secondary polycythemia group. The risk of iron deficiency was high in polycythemia vera (OR = 115; 95% CI [14.4-918.2], p < 0.0001) and the sensitivity and specificity of serum ferritin were 52.63% and 100% respectively.
UNASSIGNED: Assessment of iron deficiency should be part of the initial evaluation of polycythemia. Iron deficiency had a high specificity during polycythemia vera.

Chronic obstructive pulmonary disease (COPD) constitutes a set of heterogeneous symptoms affecting millions of people worldwide. The associated comorbidities developing in COPD involve dysregulation in physiological pathways resulting from systemic inflammation in respiratory airways. In addition to mentioning the pathophysiology, stages, and consequences of COPD, this paper also defines red blood cell (RBC) indices such as hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, red blood cell distribution width, and RBC count. It explains the role of RBC indices and RBC structural abnormalities with disease severity and exacerbations in COPD patients. Although many factors have been studied as a marker of morbidity and mortality for COPD patients, RBC indices have emerged as revolutionary evidence. Therefore, the effectiveness of evaluating RBC indices in COPD patients and their importance as a negative predictor of survival, mortality, and clinical outcomes have been debated through rigorous literature reviews. Furthermore, the prevalence, mechanisms of development, and prognosis of underlying anemia and polycythemia in COPD have also been evaluated, with anemia most significantly associated with COPD. Therefore, more studies should be conducted to address underlying anemia in COPD patients to lessen the severity and disease burden. Correcting the RBC indices in COPD patients remarkably impacts the quality of life and reduces in-patient admissions, healthcare resource utilization, and costs. Hence, it is noteworthy to understand the significance of considering RBC indices while dealing with COPD patients.

Erythrocytosis is associated with an elevation of the hemoglobin level above 16.5 g/dL in men and above 16 g/dL in women and an elevation of the hematocrit level above 49% in men and > 48% in women. In primary erythrocytosis, the defect is a clonal disorder in the myeloid compartment of the bone marrow, leading to an increased red cell production. Secondary erythrocytosis is the result of external stimuli to the bone marrow, leading to the production of red cells in excess. Secondary erythrocytosis is more common than primary erythrocytosis and has a broad differential diagnosis.
This review will discuss secondary erythrocytosis, its causes, clinical presentation, and both diagnostic and therapeutic approaches.
Although secondary erythrocytosis is more common than PV, there are still challenges and difficulties associated with the distinction between these two conditions. Moreover, there is a paucity of data and guidance when it comes to the management of certain congenital and acquired conditions. A pragmatic approach is recommended in order to identify the cause for this condition. Treatment should be directed at the management of the underlying cause.