CLINICAL AND LABORATORY CHARACTERISTICS OF THE LATENT FORM OF POLYCYTHEMIA VERA.

Area of Science:

• Hematology
• Oncology
• Internal Medicine

Background:

• Polycythemia vera (PV) is typically indicated by high hemoglobin and hematocrit.
• Latent PV (LPV) presents with normal or low levels of these indicators, making diagnosis challenging.
• LPV patients exhibit a higher incidence of thrombohemorrhagic complications (THC) compared to classic PV (CPV).

Purpose of the Study:

• To investigate the distinct laboratory and clinical features of the latent form of PV (LPV).
• To compare LPV characteristics with those of classic PV (CPV).
• To identify risk factors associated with THC in LPV patients.

Main Methods:

• Analysis of 101 PV patients diagnosed between 2019-2020, identifying 36 with LPV.
• Utilized general blood analysis, bone marrow trepanobiopsy and histology, and molecular genetic testing.
• Employed statistical analysis, including ONE-WAY-ANOVA, to compare LPV and CPV groups.

Main Results:

• LPV patients reported fewer symptoms and had smaller spleens than CPV patients.
• THC were more frequent in LPV patients, despite lower hemoglobin, hematocrit, and erythrocyte counts.
• LPV patients showed higher platelet counts; JAK2 mutation allele burden and leukocyte counts were not significantly different between LPV and CPV.

Conclusions:

• Timely and accurate diagnosis of LPV is critical due to its increased risk of THC.
• High platelet counts in LPV contribute to a greater likelihood of THC.
• LPV patients, even without elevated hemoglobin, are often in a high-risk group for THC, necessitating prompt management.