0521779407-09 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:12
Hemophilia A and B 675an increase of 20–30% because of reduced recovery. CRITICAL
TO CHECK FVIII/FIX LEVELS AFTER DOSING AND TO ADJUST
DOSE ACCORDINGLY!
➣Duration of treatment. For uncomplicated minor bleeds, 2–3
doses given q12h suffice. For major or life-threatening bleeds,
treatment must be continued for 7–10 days.
➣Both plasma-derived and recombinant products are available.
With current viral inactivation techniques, plasma-derived prod-
ucts are generally safe from HIV and hepatitis, but avoid infusing
plasma-derived product into patients who have previously been
treated only with recombinant product.
➣FOR MILD HEMOPHILIA, MAY BE POSSIBLE TO MANAGE
BLEEDS WITH DDAVP, SYNTHETIC ANALOGUE OF VASO-
PRESSIN. CONSULT A HEMATOLOGIST BEFORE GIVING CLOT-
TING FACTOR CONCENTRATES TO A PATIENT WHO HAS
NEVER RECEIVED THEM.
■Long-term management of disease
➣Multiple studies demonstrate that 3×weekly prophylactic infu-
sion of 25–40 U/kg of FVIII concentrate, begun at 1–2 yrs of age,
prevents life-threatening bleeds and greatly improves joint dis-
ease in children with hemophilia. Many patients now maintained
on such a regimen.
➣For those still treated in response to bleeds, not prophylactically,
early factor infusion in response to bleeds is critical for best out-
come.
➣For chronic synovitis/anthropathy, options include intensive
physical therapy, surgical or radioactive synovectomy, or joint
replacement.Side Effects and Complications
■Failure to infuse adequate dose of factor leads to poor control of
bleeding and resulting tissue damage.
■Current major complication of therapy is development of inhibitory
antibodies; occurs in 25% of hemophilia A pts and∼3% of hemo-
philia B. In this setting infused factor is rapidly neutralized by anti-
bodies and bleeding is uncontrolled (vide infra).
■Plasma-derived concentrates are now manufactured using viral
inactivation techniques, but these are less effective for non-
enveloped viruses. Also unclear whether they inactivate prions.
Thus, some concern remains about risk of viral blood-borne disease
transmission.