Association between polycythemia and risk of ischemic stroke in males based on the national health insurance service-health screening cohort.

BACKGROUND: Polycythemia, a state in which the hematocrit or hemoglobin (Hb) concentration in the peripheral blood increases, is associated with several thrombosis-related diseases, of which cerebral infarction is relatively common. This study aimed to investigate the association between ischemic stroke and polycythemia, as a potential risk factor. RESEARCH DESIGN AND METHODS: This study included men who had undergone national health checkups between 2002 and 2003; the data were extracted from the Korean National Health Insurance Service-Health Screening database. The primary outcome was the risk ischemic stroke; adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for ischemic stroke were calculated using Cox proportional hazards regression models. RESULTS: In total, 207,737 male participants aged 40-79 years were included in this study. At the baseline, 13972 (6.7%) participants met the polycythemia criteria (Hb >16.5 g/dL). During the study period, 897 and 12,440 cases of ischemic stroke occurred in the polycythemia and normocythemia (13.0 g/dL ≤ Hb ≤16.5 g/dL) groups, respectively. Compared with the normocythemia group, the polycythemia group showed an adjusted HR (95% CI) for ischemic stroke of 1.12 (1.04-1.20). CONCLUSIONS: The risk of ischemic stroke was higher in participants with polycythemia than in those with normocythemia.

Use of intravenous iron in cyanotic patients with congenital heart disease and/or pulmonary hypertension.

BACKGROUND: Secondary erythrocytosis is common in patients with cyanosis secondary to congenital heart disease (CHD) and/or pulmonary hypertension (PH). This compensatory mechanism aims at increasing oxygen delivery to the tissues, but it requires adequate iron stores. Optimal methods of iron supplementation in this setting remain controversial, with fears of excessive erythropoiesis and hyperviscosity symptoms. We describe our experience using intravenous ferrous carboxymaltose. METHODS AND RESULTS: 142 consecutive cyanotic patients were treated over 5.7 years (201 administrations). Mean age was 51.3 ±â€¯17.6 years and 55 (38.7%) were male. Eisenmenger syndrome (ES) was present in 41 (28.8%), other pulmonary arterial hypertension (PAH) related to CHD (PAH-CHD) in 27 (19.0%), cyanotic CHD without PAH in 16 (11.3%) and PH without CHD in 58(40.8%). Baseline haemoglobin (Hb) concentration was 14.6 ±â€¯3.0 g/dL and haematocrit 0.45 ±â€¯0.09. A 500 mg dose of intravenous (IV) iron carboxymaltose was given in 163 (81.1%) of administrations and a 1000 mg dose in 37 (18.4%). A significant improvement in average Hb, haematocrit, ferritin and transferrin saturation was observed after a median follow-up of 100.0 [70.0-161.0] days (p ≤ 0.0001 for all). There were no cases of excessive erythropoiesis resulting in new hyperviscosity symptoms and/or requiring venesection. A minor transient rash was observed in 2 patients and one patient experienced an air embolus causing a transient ischemic attack. CONCLUSIONS: Intravenous ferrous carboxymaltose appears to be safe in iron deficient patients with cyanosis due to CHD and/or PH, as long as care is taken to avoid air emboli. Further randomised studies are needed to confirm the safety and efficacy of intravenous iron in this setting.

Pulse Oximetry Screening for Critical Congenital Heart Disease after Home Birth and Early Discharge.

OBJECTIVES: To assess the feasibility of pulse oximetry (PO) screening in settings with home births and very early discharge. We assessed this with an adapted protocol in The Netherlands. STUDY DESIGN: PO screening was performed in the Leiden region in hospitals and by community midwives. Measurements were taken ≥ 1 hour after birth and on day 2 or 3 during the midwife visit. Primary outcome was the percentage of screened infants with parental consent. The time point of screening, oxygen saturation, false positive (FP) screenings, critical congenital heart defects (CCHDs), and other detected pathology were registered. RESULTS: In a 1-year period, 3625 eligible infants were born. Parents of 491 infants were not approached for consent, and 44 refused the screening. PO screening was performed in 3059/3090 (99%) infants with obtained consent. Median (IQR) time points of the first and second screening were 1.8 (1.3-2.8) and 37 (27-47) hours after birth. In 394 infants with screening within 1 hour after birth, the median pre- and postductal oxygen saturations were 99% (98%-100%) and 99% (97%-100%). No CCHD was detected. The FP prevalence was 1.0% overall (0.6% in the first hours after birth). After referral, important noncritical cardiac and other noncardiac pathology was found in 62% of the FP screenings. CONCLUSIONS: PO screening for CCHD is feasible after home births and very early discharge from hospital. Important neonatal pathology was detected at an early stage, potentially increasing the safety of home births and early discharge policy.

Effect of early versus delayed cord clamping on hematological status of preterm infants at 6 wk of age.

OBJECTIVE: To compare the effect of early cord clamping (ECC) vs. delayed cord clamping (DCC) on hematocrit and serum ferritin at 6 wk of life in preterm infants. METHODS: This randomized controlled trial was conducted in the delivery room and neonatal intensive care unit of a tertiary hospital. One hundred preterm infants born between 30 (0)/7 and 36 (6)/7 wk were randomized to either early or delayed cord clamping groups. Parental informed consent was obtained prior to the delivery. In the ECC group, the cord was clamped immediately after the delivery of the baby and in the DCC group; the cord was clamped beyond 2 min after the baby was delivered. Hematocrit and serum ferritin at 6 wk of life were the primary outcomes. Incidence of anemia, polycythemia and significant jaundice were the main secondary outcomes. RESULTS: The mean hematocrit (27.3 ± 3.8 % vs. 31.8 ± 3.5 %, p value 0.00) and the mean serum ferritin (136.9 ± 83.8 ng/mL vs. 178.9 ± 92.8 ng/mL, p value 0.037) at 6 wk of age were significantly higher in the infants randomized to DCC group. The hematocrit on day 1 was also significantly higher in the DCC group (50.8 ± 5.2 % vs. 58.5 ± 5.1 %, p value 0.00). The DCC group required significantly longer duration of phototherapy (55.3 ± 40.0 h vs. 36.7 ± 32.6 h, p value 0.016) and had a trend towards higher risk of polycythemia. CONCLUSIONS: Delaying the cord clamping by 2 min, significantly improves the hematocrit value at birth and this beneficial effect continues till at least 2nd mo of life.

Medullary nephrocalcinosis, distal renal tubular acidosis and polycythaemia in a patient with nephrotic syndrome.

BACKGROUND: Medullary nephrocalcinosis and distal renal tubular acidosis are closely associated and each can lead to the other. These clinical entities are rare in patients with nephrotic syndrome and polycythaemia is an unusual finding in such patients. We describe the presence of medullary nephrocalcinosis, distal renal tubular acidosis and polycythaemia in a patient with nephrotic syndrome due to minimal change disease. Proposed mechanisms of polycythaemia in patients with nephrotic syndrome and distal renal tubular acidosis include, increased erythropoietin production and secretion of interleukin 8 which in turn stimulate erythropoiesis. CASE PRESENTATION: A 22 year old Sri Lankan Sinhala male with nephrotic syndrome due to minimal change disease was investigated for incidentally detected polycythaemia. Investigations revealed the presence of renal tubular acidosis type I and medullary nephrocalcinosis. Despite extensive investigation, a definite cause for polycythaemia was not found in this patient. Treatment with potassium and bicarbonate supplementation with potassium citrate led to correction of acidosis thereby avoiding the progression of nephrocalcinosis and harmful effects of chronic acidosis. CONCLUSION: The constellation of clinical and biochemical findings in this patient is unique but the pathogenesis of erythrocytosis is not clearly explained. The proposed mechanisms for erythrocytosis in other patients with proteinuria include increased erythropoietin secretion due to renal hypoxia and increased secretion of interleukin 8 from the kidney. This case illustrates that there may exist hitherto unknown connections between tubular and glomerular dysfunction in patients with nephrotic syndrome.

Partial exchange transfusion results in increased cerebral oxygenation and faster peripheral microcirculation in newborns with polycythemia.

AIM: The aim of this study was to assess cerebral and peripheral oxygenation, by using near infrared spectroscopy (NIRS) and microcirculation by using side stream dark field (SDF) imaging in newborns with polycythemia before and after partial exchange transfusion (PET) therapy to investigate treatment effect on tissue oxygenation and microcirculation. METHODS: Polycythemic newborns with venous haematocrit (Htc) >70% or ≥65% with symptoms were included. NIRS measurements for cerebral and peripheral oxygenation and SDF recordings for microcirculatory flow assessment were obtained before and after PET. Fractional tissue oxygen extraction (FTOE) was calculated based on tissue oxygenation index and oxygen saturation. Wilcoxon test was used for statistical analysis. RESULTS: Fifteen newborns were included. Cerebral tissue oxygenation index, microvascular flow index and % of vessels with hyperdynamic flow increased after PET; median (range): 61.27 (51.36-61.87) versus 64.54 (54.1-74.38), 2.74 (2.46-3) versus 3.22 (2.64-3.75) and 0 (0-2.8) versus 3 (0-99.3), respectively. Whereas cerebral fractional tissue oxygen extraction (CFTOE), % of vessels with sluggish flow decreased after treatment; 0.36 (0.22-0.44) versus 0.31 (0.17-0.46), 1.4 (0-69) versus 0 (0-0.9), respectively. Peripheral oxygenation was unchanged. CONCLUSION: Partial exchange transfusion improves microcirculation in polycythemic newborns. Cerebral oxygenation increases and cFTOE decreases suggesting increased blood flow. Microvascular flow increases possibly representing reactive hyperperfusion after hemodilution. Whether these effects are beneficial require further research.

Factors predisposing to post-renal transplant erythrocytosis. A prospective matched-pair control study.

We conducted a prospective study on 81 consecutive patients who had a kidney transplant with graft function for over 3 months to evaluate the prevalence of erythrocytosis following renal transplantation (PTE) and its potential risk factors. True PTE was defined as a RBC mass > 120% of the theoretical value allowing for sex, weight and height. 18 patients (22.2%) developed PTE (RBC mass = 157 +/- 21%) with no evidence of polycythemia vera (PV), or secondary polycythemia due to reduced arterial oxygen, kidney or hepatic tumors. PTE was more common in males (p = 0.041) and less common in patients treated with recombinant erythropoietin (rHEPO) prior to transplantation. 18 non-polycythemic patients (Hb 12.6 +/- 1.3 g/dl) matched for sex, age and renal function were used as case controls. Fewer PTE patients were transfused post-transplantation (p = 0.026). At the time of diagnosis, mean serum EPO was normal and similar to that of controls. PTE patients had lower serum ferritin (p = 0.005) and more commonly received iron supplementation when PTE occurred (p = 0.003). Other clinical factors did not differ significantly between the two groups. Two patients had a thrombotic event, 6 recovered spontaneously and 11 were successfully treated with angiotensin-converting enzyme inhibitors (ACEI). The normalization of Hb, hematocrit and RBC mass in ACEI treated patients was accompanied by a decline in serum EPO (p = 0.008). We conclude that true erythrocytosis is prevalent in cyclosporine-treated renal transplant patients. PTE seems to be an idiopathic erythrocytosis. Pretransplant rHEPO treatment may limit PTE by blunting the increased sensitivity of erythroid precursors to EPO and iron supplementation, which stimulates the development of PTE. ACEI treatment is effective and safe.