Erythrocytosis has a diverse background. While polycythaemia vera has well defined criteria, the diagnostic approach and management of other types of erythrocytosis are more challenging. The aim of study was to retrospectively analyse the aetiology and management of non-clonal erythrocytosis patients referred to a haematology outpatient clinic in an 8-year period using a 3-step algorithm. The first step was inclusion of patients with Hb > 185 g/L and/or Hct > 0.52 in men and Hb > 165 g/L and/or Hct > 0.48 in women on two visits ≥ two months apart, thus confirming true erythrocytosis. Secondly, polycythaemia vera was excluded and secondary causes of erythrocytosis (SE) identified. Thirdly, idiopathic erythrocytosis patients (IE) were referred to next-generation sequencing for possible genetic background evaluation. Of the 116 patients, 75 (65%) are men and 41 (35%) women, with non-clonal erythrocytosis 34/116 (29%) had SE, 15/116 (13%) IE and 67/116 (58%) stayed incompletely characterized (ICE). Patients with SE were significantly older and had significantly higher Hb and Hct compared to patients with IE. Most frequently, SE was attributed to obstructive sleep apnoea and smoking. Phlebotomies were performed in 56, 53 and 40% of patients in the SE, IE, and ICE group, respectively. Approx. 70% of patients in each group received aspirin. Thrombotic events were registered in 12, 20 and 15% of SE, IE and ICE patients, respectively. Congenital erythrocytosis type 4 (ECYT4) was diagnosed in one patient. The study demonstrates real-life management of non-clonal erythrocytosis which could be optimized using a 3-step diagnostic algorithm.

IntroductionCholecystokinin (CCK) is involved in several metabolic pathways and CCK agonist are considered as potential novel treatment option in populations with increased metabolic risk, including polycystic ovary syndrome (PCOS). As genetic variability of cholecystokinin A and B receptor genes (CCKAR and CCKBR, respectively) may modify its biological actions, we investigated the impact of CCKAR and CCKBR genetic variability on anthropometric and metabolic parameters in patients with PCOS.Material and methodsOur cross-sectional study included 168 patients with PCOS and 82 healthy female controls genotyped for polymorphisms in CCKAR (rs6448456 and rs1800857) and CCKBR (rs2929180, rs1800843, rs1042047 and rs1042048) genes.ResultsThe investigated polymorphisms were not associated with anthropometric characteristics of patients with PCOS, however, among healthy controls carriers of at least one polymorphic CCKBR rs1800843 allele had bigger waist circumference (p=0.027) and more visceral fat (p=0.046). Among PCOS patients carriers of at least one polymorphic CCKAR rs6448456 C allele had significantly higher total blood cholesterol and LDL, and significantly lower blood glucose levels after 30, 60 and 90 minutes of the oral glucose tolerance test (all p<0.05). Healthy controls with at least one polymorphic CCKAR rs1800857 C allele were less likely to have high metabolic syndrome burden (p=0.029).ConclusionsGenetic variability in CCKAR affects lipid profile and post-load glucose levels in patients with PCOS and is associated with metabolic sydrome burden in healthy young women. Further investigation of the role of genetic variability in CCKAR and CCKBR could contribute to development of individually tailored treatment strategies with CCK receptor agonists.

Eritrocitoza je stanje povečane skupne mase eritrocitov, ki se pojavi zaradi zelo heterogenih vzrokov. Bolniki so lahko brez simptomov ali pa imajo simptome in znake povečane viskoznosti krvi. Pri obravnavi bolnika z eritrocitozo uporabljamo diagnostični algoritem, ki omogoča opredelitev vzroka eritrocitoze in ustreznega zdravljenja. V prvem koraku potrjujemo absolutno eritrocitozo s koncentracijo hemoglobina (Hb) > 185 g/L in/ali hematokritom (Ht) > 0,52 za moške ter s Hb > 165 g/L in/ali Ht > 0,48 za ženske. V drugem koraku hkrati izključujemo pravo policitemijo in iščemo sekundarne pridobljene vzroke eritrocitoze, kot so bolezni pljuč, srca, ledvic, tumorji z neustreznim izločanjem eritropoetina. Omeniti velja, da je po smernicah Svetovne zdravstvene organizacije (SZO) diagnosticiranje prave policitemije ob ustrezni klinični sliki določeno že pri nižjih vrednostih, natančneje ob Hb > 165 g/L ali Ht > 0,49 za moške ter Hb > 160 g/L ali Ht > 0,48 za ženske. V tretjem koraku bolnike, ki nam jih ni uspelo opredeliti kljub natančnim diagnostičnim preiskavam, napotimo na genetsko testiranje za opredelitev prirojene eritrocitoze. Ko izključimo pravo policitemijo, sekundarno pridobljeno in prirojeno eritrocitozo, ostane skupina oseb s t. i. idiopatsko eritrocitozo. Priporočeno zdravljenje je odvisno od vzroka eritrocitoze, najpogosteje pa vključuje jemanje acetilsalicilne kisline in ustrezno zniževanje hematokrita z venepunkcijami ob rednih kontrolah krvne slike.