Idiopathic myeloproliferative disease that is rare in
childhood. Manifestations are caused by occlusive vascular lesions.
Vaquez Disease; Osler-Vaquez Disease; Vaquez
Polycythemia; Polycythemia Vera.
5 to 6:1,000,000 in general population; affects males
more often than females.
Evocated accidentally on routine blood examination.
Diagnosis is usually made by the clinical findings of erythrocytosis,
leukocytosis, thrombocytosis, and splenomegaly. Also, the association of
blood examination and several signs, such as headaches, weakness, dyspnea,
dizziness, or tinnitus, might confirm the diagnosis. However, only two or
three of these criteria may be present. Direct determination of red cell
mass has also been suggested, but is of uncertain value because of the
difficulties in standardization and because of expense. Occasionally
reported in childhood, it occurs mostly in middle-age males. Diagnosis can
be confirmed by the association of splenomegaly, arterial saturation
>92%, and an increased red blood cell (RBC) mass (>36 mL/kg in men and
32 mL/kg in women).
Treatment includes phlebotomy and myelosuppression.
Insidious onset usually in the sixth decade of
life. Erythrocytosis, neutrophilia, thrombocytosis, and splenomegaly are
present. Thrombosis (10% with Budd-Chiari syndrome; 50% of patients
develop at least one thrombotic complication, which includes cardiovascular
accident, myocardial infarction [MI], deep venous thrombosis, and pulmonary
embolism). Bleeding and bruising, although usually minor. Pruritus, peptic
ulcer disease, gastric varices, angina, MI, congestive heart failure,
dizziness. Reports of spinal cord compression from extramedullary
hemopoiesis. Gout, secondary to increased urate turnover. Increased
perioperative bleeding and thrombosis. Associated with lymphocytic
lymphomas. Clinical features can also include headache, mental clouding, facial
plethora pruritus, hepatomegaly, high blood pressure, and gout. More severe
manifestations, caused by occlusive vascular lesions, can also be observed:
transient ischemic attack, digital ischemia, stroke, bleeding (including gastrointestinal
tract). Death occurs within 18 months without treatment and within 15 years
with appropriate treatment, but there is a 20% incidence of
transformation to myelofibrosis and approximately a 5% incidence of
transformation to acute leukemia. Vaquez disease is a myeloproliferative
disease. Hyperplasia involves all marrow elements and replaces marrow fat.
There is increased production and turnover of RBCs, neutrophils, and
Hematology consultation for
recommendations regarding phlebotomy. Check complete cell blood count and
coagulation status. Postpone elective surgery in presence of myocardial angina and
congestive heart failure. Evaluate cardiac function in cases of high blood pressure
(clinical, chest radiographs, ECG, echocardiography). Determine toxicity secondary
to chemotherapeutics. Evaluate vasoocclusive risk (full history, platelet count,
hematocrit, leukocytes) and hepatic function (echocardiography, CT, laboratory
investigations, including serum glutamic-oxaloacetic transaminase [SGOT], serum
glutamic-pyruvic transaminase [SGPT], bilirubin). Elective surgery should be
postponed until the hematocrit is reduced to <42% and platelets to
<600,000/μL. Perioperative antithrombotic therapy should be considered.
Because surgical procedures may be
hazardous, elective surgery should be postponed until the hematocrit is
reduced to <42% and platelets to <600,000/μL. Normovolemic
hemodilution can be useful. Careful intraoperative positioning is necessary.
Pulsating boots or elastic stockings placed on the patient's legs can be
used to reduce venous blood stasis. Avoid, if possible, the placement of a nasogastric tube in case of bleeding. Avoid
regional anesthesia in presence of bleeding disorder. Maintain hydration to
decrease viscosity. Avoid esophageal instrumentation in the presence of varices. Deep
venous thrombosis prophylaxis is highly recommended.
The full regimen of perioperative
antithrombotic therapy, including intravenous heparin, should be reevaluated
in patients with recent bleeding episode.
Michiels JJ, Thiele J: Clinical and pathological criteria for the
diagnosis of essential thrombocythemia, polycythemia vera, ...