Abstract
Background:
Sickle cell disease (SCD) is one of the most common inherited genetic disorders. It is caused by a mutation in the beta globin chain that allows for polymerization, which causes the phenotypic sickle shape of the red blood cells (RBCs). SCD causes patients (patients) to suffer a number of complications such as pain crises, anemia, pulmonary hypertension, chronic kidney disease (CKD) and stroke. This leads to significant mortality, hospital admissions and lengthy stays. Many patients suffer from chronic pain and require significant amounts of opioids. Hydroxyurea works well for some patients but is not a cure. Many patients do not adhere to it well. For patients with persistent severe disease, our institution has offered scheduled outpatient red cell exchange (RBCX) to reduce complications from SCD.
Methods
After obtaining IRB approval, we queried the procedure logs in our apheresis center to identify patients on the RBCX program from 1/1/2000 to 1/15/2016. We are doing a retrospective chart review of identified patients. Baseline demographics, indication for enrolling into RBCX, daily pain medication requirements (standardized to oral morphine equivalents (OME), history of DVT/PE, iron overload, CKD and pulmonary HTN. We are also evaluating compliance with RBCX, number of hospital admissions and length of stay (LOS) one year before and after enrolling in RBCX.
Results
So far, we have analyzed data from 104 patients on our RBCX program with median age of 24 (15-62). 42% are male and 86% were HbSS. 35 patients were enrolled for pain and 54 for strokes. 66% patients had been on hydroxyurea prior to enrolling but only 13% continued on it while on RBCX. 86% used intermittent central venous catheters (CVC) as access for exchange. 54% of patients had documented iron overload with 87% of those on an iron chelator. Excellent compliance with SCRX was seen (92%).
In the pain group, 18 (51%) were on hydroxyurea prior to enrolling to RBCX; only 7(20%) continued the drug while on the program. Median age in pain group was 27 (19-56), 17(49%) were males and 29(83%) HbSS. Mean HbA levels on enrolling in pain group was 45.8. The year prior to enrolling, median no of admits was 5, which dropped to 2 during first year on RBCX (decrease of 60%). Median total LOS at 1 yr prior was 16 days and 1 yr after was 2 days for the year post starting RBCX (decrease of 87.5%). In the pain group, OME(mg/day) decreased by 21.5% from 370 to 290. There were no cases of VTE associated with periodic CVC placement.
Median ferritin level prior to RBCX in the stroke group was 2988 (56-11877) with 63% of patients receiving concurrent chelator therapy.
Discussion
SCD is a morbid condition with pain being a major reason for hospital admission and stays. We describe a single center experience with RBCX. In the patients enrolled for pain, we demonstrated a decrease in opioid use (21.6% in daily OME use), in hospital admits, and length of stay. In the stroke group, there was no recurrent stroke. Interestingly, there were no admissions for pain crisis or ACS in stroke group; indicating RBCX is effective in preventing complications. Compliance was excellent in our program and complications, such as line associated VTE and infections, were not found in this initial group. Additional analyses of the rest of our population are underway. While this is a small sample, we believe RBCX is a viable treatment option in a patient population with a complicated disease and limited therapies.
No relevant conflicts of interest to declare.
