Clinical Aspects of and Therapy for Hemophilia A. Incidence. Clinical Severity, страница 9

With the exception of patients with inhibitor antibodies, those who are unreliable or unstable, or children <3 years of age, most patients are candidates for home therapy. The day-to-day supervision of the patient may often be provided by a physician in the patient's immediate geographic vicinity, with subsequent regular visits to a hemophilia center for long-term evaluation and comprehensive care. At most centers, all patients and selected family members receive an individual half-day course on the pathophysiology, diagnosis, and therapy of hemophilia. The first several infusions are administered under medical supervision. If the patient or family demonstrate both proficiency in self-infusion and good grasp of basic principles, maximum independence is allowed.

At some centers, all patients attend biannual comprehensive evaluation sessions as a minimum mandatory requirement for continuation in the program. At each session the patient is evaluated by a hematologist and an orthopaedic surgeon, a nurse, a medical social worker, an oral surgeon, a physical therapist, a vocational counselor, and, when indicated, a genetic counselor and/or a psychologist or psychiatrist. Table 106-1 Table 106-1 shows data collected on hemophiliacs treated in traditional outpatient hematology clinics for 1 year and then introduced into the formal comprehensive care program, which includes self-therapy. MLID84200752  47 It should be emphasized that the least important aspect of self-therapy is the teaching of venipuncture. The program achieves its dramatic results through patient education as well as the systematic application of the skills of a variety of appropriate medical personnel who can address the long-term problems of this lifelong disease.

Because of the many problems arising from the introduction of HIV into the blood supply in the 1970s and early 1980s, 15 comprehensive hemophilia care now also involves dealing with the acquired immunodeficiency syndrome (AIDS) and HIV. 48 Patients are examined at more frequent intervals, prophylaxis with antiretroviral agents such as zidovudine is considered, and infectious disease consultation may be obtained. Additionally, intensive counseling sessions with the patient, the family, and a social worker are provided for discussion of issues such as transmission of HIV and the impact of this infection on the life of the patient.

Complications of Therapy

Lyophilized factor concentrates revolutionized the care of persons with hemophilia. Home therapy programs were instituted and thus the long-term effects of hemorrhage were decreased and days lost from work or school lessened. MLID84200752  47 Life span gradually increased until the AIDS era. 9 Lyophilized concentrate is a pooled product made from plasma of between 2,000 and 30,000 donors. Infectious complications from transfusion-transmitted viruses began to be noted in hemophiliacs in the late 1970s and subsequently became a major concern. MLID82159302  49 However, all factor concentrates currently produced are virally inactivated, and thus infectious complications have been greatly decreased. Increased purity of concentrates has also occurred over the ensuing years.

Infectious Complications

Hepatitis

The major hepatitis viruses transmitted through plasma-derived concentrate and cryoprecipitate infusion are hepatitis B (HBV) and C (HCV). Acute HBV infection with elevated liver function tests, jaundice, and fever is uncommon in hemophiliacs, but approximately 90% of patients who were given infused concentrates before the current viral inactivation methods became available have developed antibody to HBV (HBsAb positive), indicating exposure. MLID85155884  50 A small percentage of patients, approximately 5%, have become chronic carriers (HBsAg positive). 51 Chronic carriers may be more prone to the development of symptomatic chronic liver disease or carcinoma of the liver. Delta hepatitis (HDV), a virus that requires the presence of HBV as a carrier, is also a potential risk to hemophilia patients, especially in endemic areas, since coinfection with HDV and HBV may cause fulminant hepatitis. MLID85155884  50 Persons with hemophilia who are chronic HBV carriers may also have antibodies to HDV, indicating exposure to HDV through factor concentrate. Even with virucidal methods used currently to prepare factor concentrate, HBV infections have been reported. Thus, all newly diagnosed persons with hemophilia should receive HBV vaccination. In a newly diagnosed infant, the series of three innoculations is started at birth.