COVID-19 vaccination in patients with immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an acquired autoimmune disorder that is characterized by low platelet count and increased bleeding risk. COVID-19 vaccination has been described as a risk factor for de novo ITP, but the effects of COVID-19 vaccination in patients with ITP are unknown. We aimed to investigate the effects of COVID-19 vaccination in patients with ITP on platelet count, bleeding complications, and ITP exacerbation (≥50% decline in platelet count, or nadir platelet count < 30 × 109/L with a >20% decrease from baseline, or use of rescue therapy). Platelet counts in patients with ITP and healthy controls were collected immediately before and 1 and 4 weeks after the first and second vaccinations. Linear mixed-effects modeling was applied to analyze platelet counts over time. We included 218 patients with ITP (50.9% female; mean age, 55 years; and median platelet count, 106 × 109/L) and 200 healthy controls (60.0% female; mean age, 58 years; median platelet count, 256 × 109/L). Platelet counts decreased by 6.3% after vaccination. We did not observe any difference in decrease between the groups. Thirty patients with ITP (13.8%; 95% confidence interval [CI], 9.5-19.1) had an exacerbation and 5 (2.2%; 95% CI, 0.7-5.3) suffered from a bleeding event. Risk factors for ITP exacerbation were platelet count < 50 × 109/L (odds ratio [OR], 5.3; 95% CI, 2.1-13.7), ITP treatment at time of vaccination (OR, 3.4; 95% CI, 1.5-8.0), and age (OR, 0.96 per year; 95% CI, 0.94-0.99). Our study highlights the safety of COVID-19 vaccination in patients with ITP and the importance of the close monitoring of platelet counts in a subgroup of patients with ITP. Patients with ITP with exacerbation responded well on therapy.

QTc prolongation during ciprofloxacin and fluconazole combination therapy: prevalence and associated risk factors.

AIM(S): Ciprofloxacin and fluconazole combination therapy is frequently used as prophylaxis for, and treatment of, infections in patients with haematological malignancies. However, both drugs are known to prolong the heart rate-corrected QT (QTc) interval, which is a serious risk factor for torsade de pointes (TdP). Therefore, the aim of the current study was to assess the prevalence of QTc prolongation during ciprofloxacin and fluconazole use. The secondary objective was to determine associated risk factors of QTc prolongation in these patients. METHODS: A prospective observational study was performed in patients admitted to the Erasmus University Medical Centre and treated with ciprofloxacin and fluconazole. A 12-lead electrocardiogram (ECG) was recorded at the estimated time to peak concentration (Tmax ) for the last added drug. The main outcome was the proportion of patients with QTc prolongation during treatment. Data on the following potential risk factors were collected: patient characteristics, serum electrolyte levels, dosage of ciprofloxacin and fluconazole, renal and liver function and concomitant use of other QTc-prolonging drugs and cytochrome P450 3A4 inhibitors. RESULTS: A total of 170 patients were included, of whom 149 (87.6%) were treated for haematological malignancies. The prevalence of QTc prolongation was 4.7%. No risk factors were found to be associated with QTc prolongation. The QTc interval increased by 10.7 ms [95% confidence interval (CI) 7.2, 14.1 ms] during ciprofloxacin and fluconazole combination therapy. CONCLUSION: The prevalence of QTc prolongation in patients using ciprofloxacin and fluconazole is low compared with the prevalence in the general population, which varies from 5% to 11%. In addition, no risk factors were found. Given the low prevalence, routine ECG monitoring in patients on this therapy should be reconsidered.

At high altitude in the Netherlands: secondary erythrocytosis due to HB-Malmö.

We describe two patients, a father and a son, presenting with erythrocytosis. Evaluation showed no pulmonal or cardial disorders. Owing to an elevated erythropoietin level after phlebotomy, a physiological secondary polycythaemia was suspected. A haemoglobin electrophoresis showed that our patients have a haemoglobinopathy with high affinity for oxygen, called Hb-Malmö (exon 3: c.294 C>G p.His98Gln). Hb-Malmö is a congenital disorder located on a gene at chromosome 11, in the B-chain on codon 97, decoding the α-subunit and ß-subunit of the haemoglobin. Through a mutation (CAC→CAG), histidine is replaced by glutamine. The mutation causes a disorder in the connection between the α1-subunit and ß2-subunit of the haemoglobin structure. These connections are important sites for binding oxygen. Mutated haemoglobin has a preference for an oxygenated status, which implicates that there is an increased binding and decreased release of oxygen. To compensate, there will be an erythrocytosis to transport sufficient oxygen to the peripheral tissues.

Combined infection of vertebroplasty and aortic graft after intravesical BCG treatment.

We report a 58-year-old man with spondylodiscitis by Mycobacterium bovis-BCG 3 years after intravesical BCG treatment, and shortly after a vertebroplasty. Further examination showed a psoas abscess and oedema around an endovascular aortic graft, which had been placed 1 year earlier. Puncture of the psoas abscess also grew M bovis-BCG. The patient recovered with a combination of antituberculous treatment and surgery. With hindsight a mycotic aneurysm had been present at the time of aortic graft placement and spondylodiscitis at the time of vertebroplasty. This case shows that low grade and longstanding infections may occur following intravesical BCG installation.