Coagulation disorders and inhibitors of coagulation in children from Mansoura, Egypt

Serum TNF-α Level as a Possible Predictor of Inhibitor Levels in Severe Hemophilia A

BACKGROUND

The development of factor VIII (FVIII) inhibitor in patients with hemophilia A (PWHA) is a great challenge for hemophilia care. Both genetic and environmental factors led to complications in PWHA. The development of inhibitory antibodies is usually induced by the immune response. Tumor necrosis factor α (TNF-α), one of the cytokines, might contribute to its polymorphism. In this study, we investigated the clinical factors, level of serum TNF-α, and polymorphism of c.-308G > A TNF - α gene in inhibitor development in severe PWHA.

METHODS

A cross-sectional study was conducted among all PWHA in West Java province. The clinical parameters, FVIII, FVIII inhibitor, and serum TNF-α level were assessed. The genotyping of -380G > A TNF-α gene polymorphism was performed using polymerase chain reaction and Sanger sequencing.

RESULTS

Among the 258 PWHA, 216 (83.7%) were identified as severe PWHA. The FVIII inhibitor was identified in 90/216 (41.6%) of severe PWHA, consisting of 45 high-titer inhibitors (HTI) and 45 low-titer inhibitors (LTI). There was a significant correlation between serum TNF-α level and the development of HTI (p = 0.043). The cutoff point of serum TNF-α level, which can be used to differentiate between HTI and LTI, was 11.45 pg/mL. The frequency of FVIII replacement therapy was significant only in HTI of severe PWHA regarding serum TNF-α level (p = 0.028). There is no correlation between polymorphisms of -380G > A TNF-α gene and inhibitor development (p = 0.645).

CONCLUSIONS

The prevalence of FVIII inhibitor in severe PWHA in West Java, Indonesia, was 41.6%. The frequency of replacement therapy is a risk factor for inhibitor development. Serum TNF-α level might be used to differentiate between high and low inhibitor levels in severe hemophilia A, and this might support decision making regarding treatment options for inhibitor in severe hemophilia A.

Prevalence of FVIII Inhibitors Among Children with Hemophilia A: Experience at the Jordanian Royal Medical Services

Introduction:

Replacement therapy is constantly required by Hemophilia A (HA) patients lacking coagulation factor VIII (FVIII). The most serious complication of this treatment is the development of neutralizing antibodies (inhibitors).

Aim:

The aim of this study is to determine the frequency of FVIII inhibitors among children treated for HA at the Jordanian Royal Medical Services.

Methods:

A total of 165 diagnosed HA patients receiving on-demand treatment, were tested for FVIII inhibitors between 2003 and 2018. The age range was 6 months to 16 years. Coagulation and inhibitor screening assays were performed, followed by Bethesda assay for inhibitor-positive samples to quantify FVIII inhibitor titers.

Results:

Out of the 165 patients, 111 had severe hemophilia with FVIII level < 1%, 26 had moderate hemophilia with FVIII levels of 1–5% and 28 had mild hemophilia with FVIII levels of > 5%. Twenty patients had FVIII inhibitors, of whom 18 had high titers, 2 had low titers. The mean inhibitor level in low (titer) responders was 2.40 ± 0.85 BU, as opposed to 116.25 ±169.25 BU in high (titer) responders. In terms of disease severity, 18 of the 20 patients with FVIII inhibitors had severe HA, whereas two had moderate HA. No inhibitors were encountered in the mild HA group.

Conclusion:

Inhibitors only developed in moderate and severe cases of HA. The severity of the disease and age were the main contributing factors. The association between family history of inhibitors and the incidence of inhibitor formation warrants genetic evaluations to look for relevant mutations.

The prevalence of factor VIII and IX inhibitors among Saudi patients with hemophilia: Results from the Saudi national hemophilia screening program

Hemophilia A and B are X-linked diseases that predominantly affect male patients. Patients can develop coagulation factor inhibitors, which exponentially increases the treatment cost. However, the prevalence of factor VIII and IX inhibitors in Saudi Arabia is unclear.This study aimed to determine the Saudi prevalence of factor VIII and IX inhibitors.This 4-year, 7-center, cross-sectional study evaluated the Saudi prevalences of hemophilia A and B. We collected the patients' clinical data, evaluated their disease, and tested for factor inhibitors.We included 202 patients with hemophilia (median age at diagnosis: 0.13 years, range: birth-34.8 years). The patients included 198 male patients (98%), 148 patients with hemophilia A (73.3%), and 54 patients with hemophilia B (26.7%). The patients exhibited severe factor VIII activity (<1%; 121 patients; 5.2%), moderate activity (1-5%; 7 patients; 4.9%), and mild activity (14 patients; 9.9%). Among the patients with care-related data, most patients were treated for episodic bleeding (76.8%) or received prophylaxis (22.6%); 1 patient received both treatments. Among the patients with source-related data, the factor replacements were derived from plasma (48.4%), recombinant concentrates (22.9%), both sources (14.6%), or fresh frozen plasma (14.1%). Factor VIII inhibitors were observed in 43 (29.3%) of the 147 patients, and only 1 of the 54 patients developed factor IX inhibitors. Most patients who developed inhibitors had severe hemophilia (40/44; 90.9%), and inhibitors were also common among patients who received recombinant products (14/43; 32.6%).The Saudi prevalence of factor inhibitors was similar to those among other ethnic populations.