Clinical Aspects of and Therapy for Hemophilia A. Incidence. Clinical Severity, страница 3

End-Stage Hemophilic Arthropathy

Long-standing end-stage hemophilic arthropathy has features in common with both degenerative joint disease and advanced rheumatoid arthritis. 18 The radiographic changes are shown in Figures 106-6 and 106-7. Clinically, the joint appears enlarged and "knobby," due to osteophytic bony overgrowth (Fig. 106-2). Synovial thickening and effusion, however, are not prominent. Range of motion is severely restricted, and fibrous, in contrast to bony, ankylosis is frequently seen. Subluxation, joint laxity, and malalignment are common. Hemarthroses, however, decrease in frequency.

Septic Arthritis

Although many diseases such as rheumatoid arthritis and osteoarthritis confer an increased risk of bacterial infection of a previously damaged joint, septic arthritis is a rarely reported complication of hemophilic arthritis. Pyogenic arthritis in hemophiliacs more commonly occurs in adults than in children and is usually monarticular, with a predilection for knee involvement. Compared with spontaneous hemarthrosis, septic arthritis is associated with a fever >38єC within 12 hours of presentation, an increased peripheral leukocyte count, and articular pain that does not improve with replacement therapy. A predisposing factor other than hemophilic arthrop- athy is often identifiable, including previous arthrocentesis, arthroplasty, intravenous drug usage, or immunosuppression secondary to HIV-1 infection. Staphylococcus aureus is the most frequently identified organism. MLID86153874  21

Hematomas

Small intramuscular hematomas are common and may resolve spontaneously, but large hematomas may lead to severe sequelae by way of compression of vital structures. Large hematomas may produce fever, leukocytosis, severe pain, and hyperbilirubinemia due to erythrocyte degradation. Those not adequately treated may result in fibrous organization with contractures. A large hematoma of the back and flank is seen in Figures 106-8 and 106-9.

Psoas Hematoma

Hematoma of the psoas muscle or in the muscles of the retroperitoneum may cause either pain in the lower quadrant of the abdomen (which mimics appendicitis) or pain referred to the groin (which is mistaken for hemarthrosis of the hip.) 22 Distension of the iliopsoas muscle causes the leg to be held in flexion at the hip, and compression of the femoral nerve causes pain on the anterior surface of the thigh. Increased pressure on the femoral nerve leads to paresthesia, hypesthesia, weakness of the quadriceps muscle, and even permanent paralysis of the thigh flexors.

Other Closed-Space Hemorrhage

Bleeding into the muscles of the forearm may lead to median or ulnar nerve paralysis or Volkmann's ischemic contracture of the hand. Calf lesions may lead to fixed equinovarus deformity at the ankle or to peroneal or other nerve palsies. Less common is wrist bleeding with nerve entrapment syndromes. Spontaneous or traumatic bleeding into the tongue or the muscles or soft tissues of the neck or throat may rapidly obstruct the airway, thereby requiring prompt and vigorous therapy.

Hemophilic Cysts and Pseudotumors

A large intramuscular hemorrhage may uncommonly result in the formation of a simple muscle cyst that clinically appears to be an encapsulated soft tissue area of swelling overlying muscle. Cyst formation in this setting is confined by the muscular fascial plane and results most likely from inadequate resorption of blood and clot. Subperiosteal or intraosseous hemorrhage, by contrast, may lead to a rare skeletal complication of hemophilia, a hemophilic psuedotumor. 22 Hemophilic pseudotumors are of two types: (1) the adult type that occurs proximally, usually in the pelvis or femur, and (2) a childhood type that occurs distal to the elbows or knees and carries a better prognosis than the adult type. Conservative early management of both muscle cysts and psuedotumors is indicated, including immobilization and factor replacement. If these lesions progress, however, surgical removal is indicated to avoid serious complications such as spontaneous rupture, fistula formation, neurologic or vascular entrapment, and fracture of adjacent bone. MLID77254733  23 Aspiration of a pseudotumor or cyst is contraindicated. An example of a pseudotumor is seen in Figure 106-10.