Methylene blue-photoinactivated plasma vs. fresh-frozen plasma as replacement fluid for plasma exchange in thrombotic thrombocytopenic purpura.
OBJECTIVE
Plasma exchange with fresh-frozen plasma (FFP) is the treatment of choice in thrombotic thrombocytopenic purpura (TTP). Methylene blue-photoinactivated plasma (MBPIP) has been proposed as a safer alternative to FFP, but its effectiveness in the treatment of TTP is not well established. The purpose of this study was to investigate whether MBPIP is as effective as FFP in the treatment of TTP by plasma exchange.


METHODS
A retrospective analysis was carried out of 56 TTP episodes, occurring between 1990 and 2003, which had been treated by plasma exchange. MBPIP was used for fluid replacement in 27 episodes and FFP in 29. The effect of plasma (MBPIP or FFP) on treatment outcomes was analysed by multivariate logistic regression.


RESULTS
Compared to patients treated with FFP, those receiving MBPIP had an increased risk of dying from progressive TTP [adjusted odds ratio (OR) = 31; 95% confidence interval (CI): 1.2 to > 100], a greater number of recurrences while on plasma exchange therapy (OR = 4.6; 95% CI: 1.2-17), and a lower probability of attaining a sustained remission within 9 days of starting plasma exchange (OR = 5.2; 95% CI: 1.3-20).


CONCLUSIONS
MBPIP seems to be less effective than FFP in the treatment of TTP. It is therefore prudent to avoid MBPIP until therapeutic equivalency to FFP has been established by randomized, controlled trials.
Alvarez-Larrán
A
A
Service of Haematotherapy & Haemostasis, Hospital Clínic & IDIBAPS, Barcelona, Spain.
Del Río
J
J
Ramírez
C
C
Albo
C
C
Peña
F
F
Campos
A
A
Cid
J
J
Muncunill
J
J
Sastre
J-L
JL
Sanz
C
C
Pereira
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008751:Methylene Blue / Q000528:radiation effects*; D008875:Middle Aged; D010777:Photochemistry; D010949:Plasma / Q000187:drug effects* / Q000528:radiation effects; D010951:Plasma Exchange / Q000379:methods*; D011697:Purpura, Thrombotic Thrombocytopenic / Q000401:mortality / Q000628:therapy*; D012008:Recurrence; D012074:Remission Induction; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome; D038301:Virus Inactivation
D008751:Methylene Blue