| Summary: | A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment for the requirements of the degree of Master of Medicine (Internal Medicine)
Johannesburg, 2018. === Background
Immune thrombocytopenia (ITP) is an acquired, autoimmune disorder where antiplatelet antibodies are directed to both platelets and megakaryocytes resulting in increased platelets destruction and inadequate platelet production. T-cells also play a role in autoantibody production as well as in direct lysis of platelets (cytotoxic T-cells).
The presentation of adult ITP may be acute or insidious in onset. Most cases go on to develop chronic ITP. Primary ITP accounts for approximately 80% of the patients and secondary ITP for 20%. However, in South Africa, there is a paradigm shift with an increasing number of patients with secondary ITP, contributed to mainly by human immunodeficiency virus (HIV) infection.
Splenectomy is the most definitive therapy for ITP. It has the highest likelihood of all the current treatment options of producing a cure. The overall response rate is 70-90% (CR 50-60%, PR 20-30%, relapse rate 15%). It is effective for persistent and chronic ITP after failure of corticosteroid therapy. It is recommended that splenectomy be delayed for at least six months (and preferably 12 months) from diagnosis due to the chance of a spontaneous remission (5-11%). Although open splenectomy and laparoscopic splenectomy have similar efficacy, laparoscopic splenectomy has fewer surgical complications, including less postoperative pain, earlier general diet tolerance and shorter hospital stay.
There is a paucity of data with regard to ITP, and more specifically, looking at the efficacy and safety of splenectomy in the South African context. Furthermore, in view of the increased prevalence of HIV as the most common cause of secondary ITP, it is important to ascertain the feasibility, safety and efficacy of splenectomy in secondary ITP.
Therefore, the current study aimed at exploring the impact of splenectomy as a therapeutic option in ITP, in adults at CHBAH over a period of 29 years (01/01/1986- 31/12/2014).
Patients and Methods
This is a retrospective review of the records of ITP patients who had a splenectomy, during the aforementioned study period at the Clinical Haematology unit, Chris Hani Baragwanath Academic Hospital.
The aim of the study was to study the impact of splenectomy as a therapeutic modality in patients with ITP, specifically looking at the indication, timing, outcome, response, duration of response and complications of splenectomy in ITP. The efficacy and safety of laparoscopic versus open splenectomy in ITP was assessed as well as a comparison of the efficacy, safety and outcome of splenectomy in primary and secondary ITP.
Results and Discussion
A total of 56 splenectomised ITP patients’ records were reviewed. Of these, 43 were female (77%) while 13 were male (23%). The median age of the patients was 29 years, with a range of 18- 53 years.
Majority of the patients had primary ITP (n=42, 75%), and the remaining (n=14, 25%) had secondary ITP. Of the fourteen patients with secondary ITP who had a splenectomy, 11 had an underlying autoimmune aetiology. Nine patients (82%) were diagnosed with SLE while concomitant auto-immune haemolytic anaemia (Evan’s syndrome) and mixed connective tissue disease accounted for 1 each (18%), of the remaining patients, respectively.
In this study, there were three HIV positive patients who had a splenectomy accounting for 5.4% of all splenectomised patients with ITP.
The surgery of choice in this study was open splenectomy (n=51, 91%). Only five patients underwent laparoscopic splenectomy of which two were later converted to open splenectomy because of complications.
Failed corticosteroid (CS) therapy (98.2%) was the commonest indication for splenectomy in this study. These patients were either steroid dependent or showed only a partial response. Similarly, they also experienced disabling side effects from high doses and/or prolonged use of CS therapy. One patient had splenectomy as a result of poor compliance (1.8%).
In the splenectomised patients, platelet counts one year post splenectomy (mean = 231.19 x 109/l ± 162.643) were significantly higher than the platelet counts prior to splenectomy (mean = 26.22 x 109/l ± 31.552 and p-value= 0.00).
Three patients (5.4%) experienced infections requiring hospitalization. Two patients had thrombotic complications, while five patients had bleeding manifestations up to the time of the last visit.
Overall, 37 patients (66%) had a complete remission, while seven patients (12.5%) had a partial remission. Six patients (10.8%) showed no response to splenectomy. In four patients (7%), the outcome was unknown. Two patients (3.6%) died, one patient from a complication of surgery and the other patient from sepsis four years post splenectomy.
Conclusion
The role of splenectomy in ITP continues to be reassuring, particularly in our setting where the ‘newer’ agents, such as rituximab (used as an off-label indication in ITP), and thrombomimetics, which are not yet accessible due to high cost, are challenging the role of splenectomy. Splenectomy is the preferred second line therapy after the patient has failed CS therapy. Although the minority of the patients had a laparoscopic splenectomy, with time and experience, laparoscopic splenectomy should become the procedure of choice, especially in conditions such as ITP, where the spleen is not enlarged, and the procedure is highly technically feasible. Furthermore, the outcome for primary versus secondary ITP was equally favourable.
However, there were significantly less number of secondary ITP patients in this study.
The findings in this study are limited by its retrospective nature. For some patients data was missing and the files could not be reviewed. Ideally, a larger sample size would have added to the strength of this study. Nevertheless, we believe that the findings are a fair representation of the role of splenectomy in ITP, in the public sector South African context, based on this retrospective review from a large single centre, over a period of 29 years. Therefore, splenectomy remains a therapeutic modality of choice in this setting, particularly in patients with persistent and chronic ITP, who have failed prior CS therapy. === LG2018
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