History۬A 55 year old otherwise healthy patient had fatigue/ headache of approximately 3 months duration. Attended

professional conference on a Tuesday and noted that sound was tinny. Went to see family doctor who noted sinuses

inflamed and fluid in left ear. Prescribed antibiotics and steroidal nasal spray. No improvement by Friday, with some

loss of hearing on left side, with everything sounding muffled. The patient went to see otolaryngologist on Friday.

Different antibiotics prescribed for fluid in ear. Over the next 4 days, patient became increasingly dizzy and had

progressive hearing loss. Phone calls to otolaryngologist regarding hearing loss and dizziness led to the response, if

it’s a virus, this can happen.
On Wednesday, patient went to an emergency room. Lab work indicated extremely high WBC’s (800,000) and diagnosis of

Chronic Myeloid Leukemia (CML). The patient was originally designated to be in blast crisis; however, initial labs were

misread and no blasts were present.
Day 1: Patient transferred from ER to ICU and treatment is initiated Leukapheresis performed on patient.۬Large doses of

solu cortef are given to the patient.
Day 3: The Patient is transferred to a regional university hospital. White blood cell count at this point

350,000.۬Treatment continues and expands:۬Continued leukapheresis
Initiate hydroxyurea and allopurinol treatment for 1 week Start on prednisone
Day 7۬White count below 3,000.۬Bone marrow biopsy performed. Analysis of chromosomes by cytogenetics shows 25 of 25

chromosome spreads with the Philadelphia chromosome.۬Discharged 3 days later with Allopurinol, Dexamethasone, and

Gleevec 400 mg/daily.
3 months later:۬CML:۬Patient is improving and white counts are in the normal range; however, hearing has not returned.

Additional diagnostic tests were performed to identify the cause of hearing loss. The CSF was analyzed via a spinal tap,

and no CML cells were found, suggesting a lack of CNS involvement. An MRI was originally performed at the regional

university hospital and again at a 3-month follow up. The original MRI showed cloudiness in inner ear. The follow up

MRI showed significant improvement. Dexamethasone was finally discontinued.
4 year follow-up:۬Patient is doing well with normal blood counts. Hearing never returned on its own and cochlear

implants were ultimately used to restore hearing (1 implant was paid by employer-provided insurance and 1 implant was

paid out of pocket).
Disease Management€¨Patient continues treatment with Gleevec €“ 400mg daily
€“ monitor for disease recurrence:€¨blood work is done every 7 weeks (CBC with Differential; Chem Profile).€¨Peripheral PCR

every 3 months.۬Bone Marrow biopsy with cytogenetic testing and bone marrow PCR every 6 months.

QUESTION:
What is leukapheresis and how is it therapeutically beneficial in this case?