Sickle Cell Anemia

Patient Presentation:
S.K., a 48 year old African American women, presents to the ED with 4 days of intractable pain, uncontrolled by her home pain regimen (10mg oxycodone PO q2hr prn).  The pt rates the pain a “10 of 10”, describing it as sharp and located in elbow and knee joints and abdomen.  In addition, pt notes low grade fever for past 2 days.  Pt’s current pain is consistent with previous episodes of sickle pain crisis which have been increasing in frequency; approximately one per month.  Of note, her most recent hospitalization (9 weeks prior) required a blood exchange transfusion. Physical exam is significant for BP 130/60, pulse 98, RR 18, SaO2 94% on RA, temp 38.1. Heart: rate is regular, no murmurs. Lungs: Clear bilaterally, no wheezing or crackles. Abdomen: soft, tender, + bowel sounds. No edema, swelling, warmth or erythema.  Labs upon arrival are significant for Hgb 8.2, Hct 23.5%, reticulocyte count 12.4%, WBC 11.4.

Differential List:
Septic Arthritis
(If pt. had not already tested + for presence of homozygous HbS, then additional differentials would include testing for other chronic anemia’s that involve abnormal Hgb such as Thalassemia)
Sickle Cell Pain Crisis

Diagnosis:
Based on patients previous similarity to past sickle cell pain crisis, elevated reticulocyte count, and low Hgb and Hct, pt was diagnosed with sickle cell pain crisis. Bone marrow transplant offers the only potential cure for sickle cell disease.  Due to difficulty finding donors and serious risks associated with this, the treatment for sickle cell disease is symptom management. For pain crisis, the goal is to treat pts to where they can manage their pain at home.

Treatment:
Pt’s sickle cell pain crisis was managed with IV fluids, supplemental oxygen to keep SaO2 above 94%, daily folic acid and hydroxyurea (stimulates production of fetal Hgb and is thought to prevent pain crisis, however it also increases your chance of infections).  Pain was managed with a fentanyl PCA and fevers managed briefly with Zosyn® and vancomycin until drawn blood cultures were all negative for growth, however pt did have a + sputum culture for MRSA, which she has been known to be colonized in the past.  Pt was not responsive to sickle cell pain crisis therapy and continued to hemolyze as evidenced by increasing reticulocyte count and decreasing Hgb/Hct. Pt therefore required a red blood cell exchange; this will increase oxygen carrying capacity of red cells and replacement of sickle cells by “normal” cells can help prevent further vaso-occlusion and decrease the rate of hemolysis.

Outcome:
Pt received an 8 unit packed red blood cell exchange transfusion without complication and was weaned off IV pain medication.  She was discharged home with MS Contin® 60mg b.i.d. and oxycodone 10mg q2hr prn.  Pt will continue daily folic acid and hydroxyurea. She will continue to follow up with her hematologist to check her CBC values and will likely need further hospitalizations to manage her sickle cell disease in the future.
Case created by Stefanie Kelly, 2011.