Page 1982 - Hematology_ Basic Principles and Practice ( PDFDrive )

1756 Part XI Transfusion Medicine

thrombocytopenia. Studies evaluating the use of IVIg for NAIT are needing protection against infection. Initially, serial IgG level deter-
limited, but unlikely to improve because of the rarity of the condi- mination may allow the physician to individualize the dose and
tion. The treatment of NAIT during pregnancy is maternal admin- schedule. These are affected by the recovery, half-life, redistribution,
istration of 1.0 g/kg IVIg weekly as a first-line therapy beginning at and catabolism of IVIg, which vary from product to product and
20 weeks of gestational age with the use of glucocorticosteroids, or patient to patient. Patients with ITP are usually initially treated with
2.0 g/kg weekly if steroids are not used. Once at 32 weeks of gesta- 400 to 1000 mg/kg daily for 2 to 5 consecutive days with a maximum
tion, the IVIg dose is increased to 2.0 g/kg weekly with corticosteroids. dose of 2.0 g/kg. Maintenance doses of 400 to 1000 mg/kg/dose
Moreover, the neonate may need to receive IVIg and platelet transfu- every 3 to 6 weeks is recommended in some patients (particularly
sions after delivery to increase fetal platelet counts to prevent intra- children) based on clinical response and platelet count. Kawasaki
cerebral hemorrhage at a dose of 1.0 g/kg (Chapter 131). disease is treated with 2.0 g/kg as a single dose in combination with
aspirin. Currently, direct comparisons between different IVIg formu-
lations or brands are lacking, and so evidence-based recommendations
Hemolytic Disease of the Fetus and Newborn cannot be made along these lines.

Hemolytic Disease of the Fetus and Newborn (HDFN) results from
maternal RBC alloantibodies binding to fetal/neonatal RBCs and Adverse Effects
may result in hemolysis, leading to anemia or hydrops fetalis and
death depending on the severity. Two metaanalyses reveal that IVIg Infusions of IVIg should be started slowly and patients should be
significantly reduces the need for exchange transfusions in patients closely monitored. If the initial rate (0.5 mL/kg/h) is well tolerated,
with HDFN. IVIg is now consequently recommended at a dose of the rate can be increased gradually, but not more than eightfold. That
0.5 to 1.0 g/kg to treat newborns with HDFN if there is established said, initial and maximum infusion rates vary by IVIg product, and
jaundice and a rising total serum bilirubin despite phototherapy. product inserts should be consulted prior to selecting an appropriate
In addition, maternal IVIg infusion (with or without therapeutic infusion rate. Fever, headache, nausea, vomiting, fatigue, backache,
plasma exchange) has been used in severe cases of HDFN where leg cramps, urticaria, flushing, elevation of blood pressure, and
treatment must occur before the ability to perform intrauterine thrombophlebitis may be seen. Adverse events have been reported in
transfusions. 2% to 10% of infusions. IgA-deficient patients may have IgG anti-
IgA antibodies, which can cause anaphylactic reactions. This compli-
cation is rare and may be avoided by using products with a lower
Posttransfusion Purpura concentration of IgA. Aggregated IgG may produce chills, nausea,
flushing, chest tightness, and wheezing. Rarely, IVIg preparations
PTP is a rare complication of transfusion resulting in acute, profound contain RBC antibodies that can produce hemolysis or interfere with
thrombocytopenia, secondary to platelet antibodies that destroy both serologic evaluations, including RBC compatibility testing. IVIg
transfused and autologous platelets. While the evidence evaluating treatment will produce a false positive direct antiglobulin test, and
the effect of IVIg in these patients is limited to multiple case reports, sometimes positive hepatitis and CMV serologies. Serum sickness can
the available evidence suggests that IVIg should be a first-line therapy also occur. Lastly, high-dose IVIg therapy has been associated with
for this condition. PTP treatment with IVIg at a dose of 2 g/kg over thrombosis, reversible acute renal failure, TRALI, and aseptic men-
2 days or 0.4–0.5 g/kg daily for 5 days can result in a rapid increase ingitis. Improved manufacturing processes currently in place render
in platelet count. IVIg free of enveloped and nonenveloped viruses.

Sepsis and Septic Shock in Adults HYPERIMMUNE IMMUNOGLOBULIN PRODUCTS

The use of IVIg in adult patients with bacterial sepsis or septic shock Hyperimmune globulins are concentrated immune globulins with
is potentially beneficial. One randomized control trial reveled that in specificity for an antigen, or group of antigens. These products are
ICU patients with intraabdominal sepsis and shock, IVIg with manufactured in a similar manner to that used for IVIg product
antibiotics was superior to antibiotics with albumin in improving production. However, donors for these specific products are unique
patient survival. Encouraging results have also been identified in in that they have high titers for the Ig specificity of interest. The
patients receiving IVIg for streptococcal toxic shock syndrome, but donor high titers can be achieved via natural immunity, prophylactic
further studies are currently needed. immunization, or target immunization, depending on the antibody
of interest. These products are generally used to provide passive
immunity for a variety of conditions that are described in more detail
Stiff-Person Syndrome in the following sections (Table 115.5).

Stiff-person syndrome is a neurologic disorder associated with truncal
and limb rigidity and heightened sensitivity. One small randomized TABLE
control trial suggests that IVIg could play a positive role in improving 115.5 Hyperimmune and Intramuscular Immunoglobulins
stiffness and sensitivity symptoms. Currently, IVIg is considered a
second-line therapy for those who fail or cannot tolerate Antithymocyte globulin
GABA (glutamic acid decarboxylase)-ergic medications. A dose of Botulism immunoglobulin
2.0 g/kg given over 2 to 5 days is the current recommended starting Cytomegalovirus immunoglobulin
dose. Hepatitis A immunoglobulin
Hepatitis B immunoglobulin
Rabies immunoglobulin
Dosage Respiratory syncytial virus immunoglobulin
Rh(D) immunoglobulin
The dosage and frequency for IVIg varies significantly depending on Tetanus immunoglobulin
the age of the patient and the clinical indication. Many typical Vaccinia immunoglobulin
dosages were described in the preceding section. In general, patients Varicella-zoster immunoglobulin
require 200 to 800 mg/kg intravenously every 3 to 4 weeks to achieve Western equine encephalitis immunoglobulin
adequate IgG levels if immunodeficient (usually 500 mg/dL) and