Role of cytokines in Trypanosoma brucei-induced anaemia: A review of the literature

Background Anaemia is an important complication of trypanosomiasis. The mechanisms through which trypanosomal infection leads to anaemia are poorly defined. A number of studies have implicated inflammatory cytokines, but these data are limited and inconsistent. In this article, we reviewed the published literature on cytokines associated with Trypanosoma brucei infections and their role in the immunopathology leading to anaemia. Methodology Articles were searched in PubMed through screening of titles and abstracts with no limitation on date of publishing and study design. Articles in English were searched using keywords “African trypanosomiasis”, “sleeping sickness”, “Trypanosoma brucei”, in all possible combinations with “anaemia” and/or “cytokines”. Results Twelve articles examining cytokines and their role in trypanosomeinduced anaemia were identified out of 1095 originally retrieved from PubMed. None of the articles identified were from human-based studies. A total of eight cytokines were implicated, with four cytokines (IFN-γ, IL-10, TNF-α, IL-12) showing an association with anaemia. These articles reported that mice lacking TNF-α were able to control anaemia, and that IFN-γ was linked to severe anaemia given its capacity to suppress erythropoiesis, while IL-10 was shown to regulate IFN-γ and TNF-α, providing a balance that was associated with severity of anaemia. IFN-γ and TNF-α have also been reported to work in concert with other factors such as nitric oxide and iron in order to induce anaemia. Conclusion IFN-γ, IL-10, and TNF-α were the three major cytokines identified to be heavily involved in anaemia caused by Trypanosoma brucei infection. The anti-inflammatory cytokine, IL-10, was shown to counter the effects of proinflammatory cytokines in order to balance the severity of anaemia. The mechanism of anaemia is multifactorial and therefore requires further, more elaborate research. Data from human subjects would also shed more light.

Transcatheter Closure of Atrial Septal Defects in a Center With Limited Resources: Outcomes and Short Term Follow-Up

Background: Transcatheter closure of atrial septal defects (ASD) has been accepted world-wide as an alternative to surgical closure with excellent results. This interventional, non-surgical technique plays an important role in the treatment of ASD mostly in the developing world where resources are limited. Objectives: To report the outcomes and short term follow-up of transcatheter closure of ASD over a 12-year period at our institution with limited resources. Patients and Methods: This retrospective study included all patients with the diagnosis of secundum ASD and significant shunting (Qp/Qs > 1.5:1) as well as dilated right atrium and right ventricle who had transcatheter closure at Integrated Cardiovascular Center (PJT), Dr. Cipto Mangunkusumo Hospital between October 2002 and October 2014. One hundred fifty-two patients enrolled in this study were candidates for device closure. Right and left heart cardiac catheterization was performed before the procedure. All patients underwent physical examination, ECG, chest X-ray and transthoracal echocardiography (TTE) prior to device implantation. Results: A total of 152 patients with significant ASD underwent device implantation. Subjects’ age ranged from 0.63 to 69.6 years, with median 9.36 years and mean 16.30 years. They consisted of 33 (21.7%) males and 119 (78.3%) females, with mean body weight of 29.9 kg (range 8 to 75; SD 18.2). The device was successfully implanted in 150 patients where the majority of cases received the Amplatzer septal occluder (147/150; 98%) and the others received the Heart Lifetech ASD occluder (3/150, 2%), whereas two other cases were not suitable for device closure and we decided for surgical closure. The mean ASD size was 19.75 (range 14 - 25) mm. During the procedure, 5 (4.9%) patients had bradycardia and 3 (2.9%) patients had supraventricular tachycardia (SVT), all of which resolved. Conclusions: In our center with limited facilities and manpower, transcatheter closure of atrial septal defect was effective and safe as an alternative treatment to surgery. The outcome and short-term follow-up revealed excellent results, but long-term follow-up is needed.