Safety and efficacy of microwave versus radiofrequency ablation for large hepatic hemangioma: a multicenter retrospective study with propensity score matching.

OBJECTIVES: To compare the safety and efficacy of microwave ablation (MWA) and radiofrequency ablation (RFA) for such hemangiomas (5-9.9 cm in diameter). METHODS: This multicenter retrospective cohort study investigated the differences in technical success, ablation time, complete ablation, complications, hospital stay, and clinical response between MWA and RFA. A total of 452 patients with hepatic hemangiomas were screened. Propensity score matching was performed. Univariable and multivariate regression analyses were used. RESULTS: Among the 452 patients, 394 met the eligibility criteria and completed the follow-up. After the propensity score matching analysis, 72 pairs of patients were created. No technical failures were found. The RFA group had a longer ablation time (48.63 ± 18.11 min versus [vs.] 37.18 ± 15.86 min, p < 0.001), higher morbidity of hemoglobinuria (77.78% vs. 50.00%, p < 0.001), and longer hospital stay (5.01 ± 1.56 days vs. 4.34 ± 1.42 days, p < 0.05) than the MWA group. The treatment methods (p = 0.032, OR = 0.105, 95% CI = 0.013-0.821), size of the hemangioma (p = 0.021, OR = 5.243, 95% CI = 1.285-21.391), and time of ablation (p = 0.031, OR = 1.145, 95% CI = 1.013-1.294) were significant independent risk factors associated with hemoglobinuria. No recurrence or delayed complications were observed. There were no differences in complete ablation, clinical response, and health-related quality of life between the groups. CONCLUSIONS: MWA and RFA appear to be effective treatments for large hepatic hemangiomas. However, MWA had a shorter ablation time than RFA, and MWA was associated with fewer hemolysis-related complications and shorter hospital stays. KEY POINTS: • MWA and RFA appear to be effective treatments for large hepatic hemangiomas. • MWA had a shorter ablation time than RFA. • MWA was associated with fewer hemolysis-related complications and shorter hospital stays.

Intravascular hemolysis secondary to aorto-atrial fistula presenting as red urine.

Intravascular hemolysis is a rare but potentially life threatening cause of red urine characterized by brisk hemolysis and release of large amounts of hemoglobin into the urine. We present an unusual case of red urine in a 20-year-old male who was subsequently diagnosed with intravascular hemolysis due to an aorto-atrial fistula. Fistula formation was likely secondary to a recently implanted atrial septal occluder, which is a reported but exceedingly rare complication of the device. We discuss the diagnostic approach to hemolytic anemia and conclude with a literature review of other cases of device associated fistula formation and hemolysis.

Hemostatic alterations in splenectomized and non-splenectomized patients with beta-thalassemia/hemoglobin E disease.

Beta-thalassemia/hemoglobin (Hb) E is a hereditary hemolytic anemia with varying degrees of severity. Severely affected patients are treated with blood transfusion and/or splenectomy in order to maintain an optimum level of hemoglobin for normal growth and physical activities. As thrombosis has been observed among splenectomized patients, we have investigated alterations in coagulation and fibrinolysis in beta-thalassemia/Hb E patients. Plasma levels of prothrombin, fibrinogen, factors V, VII, VIII, IX and XI, protein C, protein S, thrombin activatable fibrinolysis inhibitor (TAFI) and prothrombin fragment 1+2 were determined in 61 patients (21 non-severe non-splenectomized, 18 severe non-splenectomized, 22 severe splenectomized) and 28 healthy individuals. Serum levels of D-dimer, ferritin, aspartate transaminase and alanine transaminase were also measured. All severe patients received regular blood transfusion. Prothrombin fragment 1+2 and D-dimer were significantly elevated in splenectomized patients compared to the healthy control subjects, whereas levels of proteins C, protein S, TAFI, fibrinogen, and factors V and VIII in the splenectomized groups were statistically lower than those in control group. There are no statistical differences for the other parameters measured between patients and controls. Coagulation tests showed only significantly reduction in TAFI and factor V and VIII levels in severe splenectomized group in comparison with severe non-splenectomized patients. These results demonstrate the existence of a low grade consumptive coagulopathy among blood-transfused splenectomized patients with severe clinical manifestations, indicating that these patients may have a higher risk for thrombosis than comparable patients with intact spleen.

Haemolysis following implantation of duct occlusion coils.

OBJECTIVES: To describe the incidence and management of haemolysis after transcatheter coil occlusion of the arterial duct. DESIGN: Prospective clinical and echocardiographic follow up of patients who have undergone implantation of the Cook detachable duct occlusion coil. SETTING: Tertiary paediatric cardiac centre. PATIENTS: Five cases of haemolysis (two girls aged 6 and 11 months; three boys aged 6, 17, and 14 months) from a series of 137 duct coil implantations. MAIN OUTCOME MEASURES: The occurrence of clinically significant haemolysis after implantation of duct occlusion coils and resolution of haematuria after completion of duct occlusion. RESULTS: Haemolysis was detected in five of 137 procedures following implantation of Cook detachable duct coils. Four patients became symptomatic 12 hours after the procedure but in one haemolysis was detected three months later. Resolution of ongoing haemolysis was achieved within 48 hours of detection with further coil implantations, but haematuria persisted for up to 10 days. In one patient the extensive destruction of erythrocytes resulted in acute renal failure requiring peritoneal dialysis. CONCLUSIONS: Haemolysis is an important complication after duct coil implantation. It occurred in 3.6% of 137 procedures in this series and is most likely to occur in young patients with relatively large ducts. Further coil implantation to occlude the duct completely is not only successful but technically relatively straightforward and should be undertaken early if major complications such as severe anaemia and renal failure are to be avoided.

Interaction of hemoglobin E and pyrimidine 5' nucleotidase deficiency.

A Bangladeshi family is described in which the genes for both hemoglobin E (Hb E) and pyrimidine 5' nucleotidase deficiency are segregating. An individual homozygous for both these conditions has a severe hemolytic anemia, whereas family members who are homozygous for Hb E are asymptomatic and those homozygous for pyrimidine 5' nucleotidase deficiency have the mild hemolytic anemia that is characteristic of this disorder. Globin-chain synthesis experiments have shown that the mechanism underlying the interaction between these two genotypes is a marked decrease in the stability of Hb E in pyrimidine 5' nucleotidase-deficient red blood cells (RBCs). It has also been found that in the enzyme-deficient RBCs in which Hb E is highly unstable, free alpha-chains, though not beta E-chains, acoumulate on the membrane. In view of the increasing evidence that the hemolysis associated with pyrimidine 5' nucleotidase deficiency results not only from an increase in the level of erythrocyte pyrimidines, but also from inhibition of the hexose monophosphate shunt activity in young erythrocytes, it is likely that the marked instability of Hb E in the enzyme-deficient cells results from oxidant damage acting on a mildly unstable Hb variant. These observations may have important implications for the better understanding of the pathophysiology of Hb E/beta-thalassemia, globally the commonest important form of thalassemia.

Hydroxyurea increases hemoglobin F levels and improves the effectiveness of erythropoiesis in beta-thalassemia/hemoglobin E disease.

Hydroxyurea (HU) is one of several agents that have been shown to enhance hemoglobin (Hb) F levels in patients with sickle cell disease and may be useful as a therapy for beta-globinopathies. However, limited information exists on the effects of HU in patients with thalassemia. Accordingly, we examined the hematologic effects of orally administered HU in 13 patients with beta-thalassemia/Hb E, including four patients who had been splenectomized. These patients were treated with escalating doses (final range, 10 to 20 mg/kg/d) for 5 months and were observed in the outpatient hematology clinic every 2 to 4 weeks. Complete blood counts including reticulocyte counts, amounts of Hb E and Hb F, G gamma:A gamma and alpha:non-alpha globin biosynthetic ratios were evaluated before and during treatment. Almost all patients responded with an average increase of 33% in Hb F levels, from a mean (+/- SD) of 42% +/- 11% to 56% +/- 8% (P < .0001), and a reciprocal decline in the percentage of Hb E from 59% +/- 9% to 49% +/- 8% (P < .001). Reticulocytosis was decreased from a mean (+/- SD) of 18.0% +/- 15.6% to 11.7% +/- 9.1% (P < .05); there was also a slight (10%) but statistically significant increase in hemoglobin levels and an improved balance in alpha:non-alpha globin chains ratios. The side effects were minimal in most patients, although these patients tended to tolerate a lower dose of HU before significant myelosuppression than has been our previous experience in sickle cell disease. One splenectomized patient died of sepsis during the trial. We conclude that increased Hb F production in beta-thalassemia/Hb E patients, with an improvement in the alpha:non-alpha globin ratios and, probably, the effectiveness of erythropoiesis, can be achieved using HU. Longer trials of HU in this population, including at other doses and in combination with other agents, appear warranted.