Biomedical subjects
Publications and source records attributed to J A Fort.
Factor VII deficiency is a serious, potentially lethal disorder of blood coagulation caused by a defect in hepatic factor VII synthesis. We report two children, sisters, both with severe, recurrent hemorrhagic complications from factor VII deficiency, successfully treated with orthotopic liver transplantation. Postoperatively, they remain symptom free with normal coagulation profiles.
OBJECTIVE: To describe a case of pseudotumor cerebri associated with the administration of intermediate-dose cytarabine. CASE SUMMARY: An 11-year-old Hispanic boy with acute myeloblastic leukemia developed symptoms of pseudotumor cerebri (headache, diplopia, photophobia, nausea, vomiting) after receiving chemotherapy including cytarabine. The patient improved after a lumbar puncture and treatment with prednisone and acetazolamide, and is now asymptomatic. DISCUSSION: Pseudotumor cerebri is a condition usually associated with obese women of child-bearing age. Case reports in pediatric patients are unusual. Several medications have been implicated in causing pseudotumor cerebri, including antimicrobials (tetracycline, naladixic acid), amiodarone, lithium carbonate, vitamin A and its derivatives, growth hormone, and corticosteroids. Chemotherapy agents reported to cause pseudotumor cerebri include busulfan with cyclophosphamide, and the combination of vinblastine, cisplatin, and bleomycin. Most of the information on medication-induced pseudotumor cerebri is in the form of case reports. Different mechanisms for causing this condition have been offered for individual medications. Most of these explanations involve fluid imbalance or interference with the Na+/K+ adenosine triphosphatase pump. Controlled studies are difficult because this condition is an unpredictable and rare occurrence. Cytarabine has frequently been associated with neurologic toxicities, but few reports of pseudotumor cerebri can be found. CONCLUSIONS: The exact cause of pseudotumor cerebri in this patient is unknown, but cytarabine seems a likely cause. The mechanism by which cytarabine could cause this reaction is unclear.
Various procedures are useful in purging bone marrow of pre-B lineage contamination prior to autologous bone marrow transplantation. Specific monoclonal antibodies are used in combination with complement, magnetic microspheres, chemotoxins, phototherapy or lectins. In this setting, the usual monoclonal antibody cocktail consists of CD9 (DU-ALL-1), CD10 (WCMH 15.14) and CD19 (HD37). Antigens reacting with all three monoclonal antibodies are present on early and mature pre-B lymphocytes. However, CD9 positive antigens have also been shown to be present on megakaryocytes, platelets and mature granulocytes. In our studies, we have found that CD10 and CD19 expression predictably vary according to disease status, with low positivity in remission and higher positivity in relapse. CD9 expression, however, varies independently of disease status and is frequently inconsistent within individual patients. As such, use of CD9 for marrow purging may result in the removal of a broad range of cell populations not related to the underlying disorder.
Recently, a form of T-cell lymphoma associated with seropositivity for human T-lymphotrop virus type 1 (HTLV-1) antibody has been described in the adult population. The lymphoma frequently presents with massive hepatosplenomegaly, lymphadenopathy and circulating malignant cells, with a normal bone marrow. HTLV-1-associated lymphoma has been seen most frequently in adults from Japan, the Caribbean, and the southeastern United States. We report the first known case of a child with a lymphoma having the clinical and serological features of an HTLV-1-associated T-cell lymphoma.
Osteogenic sarcoma is a malignant bone tumor that occurs more frequently in long bones of the extremities, mainly in the second and third decades of life. It rarely occurs in children younger than 5 years of age. We describe the case of a 3 9/12 years old boy, who is one of the youngest patients described in the literature. This patient had an aggressive disease, with pulmonary metastases at the time of diagnosis. The disease progressed rapidly despite surgery and chemotherapy. Diagnosis was delayed probably because of the unusual presentation of this disease at this age.
A major concern of physicians caring for patients is the development of hyperkalemia, a potentially life-threatening event requiring accurate determination of its etiology. After metabolic and iatrogenic causes have been excluded, factitious hyperkalemia must be considered, one cause of which may be the method of laboratory determination. Hyperkalemia associated with thrombocytosis has been previously described but is a fact commonly overlooked in the evaluation of a patient with hyperkalemia. We compared the potassium levels in simultaneous serum and plasma samples from patients with normal and elevated platelet counts, since platelet activation during clot formation is associated with release of potassium. We found consistently higher potassium levels in serum (containing products of activated platelets) than in plasma (containing nonactivated platelets). The greatest discrepancy in potassium levels was in patients with thrombocytosis. This preliminary study suggests that if there is no obvious explanation for an elevated serum potassium the plasma potassium level should be measured, particularly in patients with elevated platelet counts.
Because of retrospective analysis showing survival to be related to primary tumor size, in February 1982 a study to test this hypothesis prospectively was begun at the University of Florida. Patients with primary tumors 8 cm or less in maximum diameter and no metastases received adjuvant chemotherapy consisting of vincristine, cyclophosphamide, doxorubicin, and dactinomycin plus radiotherapy or surgery (standard-risk protocol). All others received a similar regimen followed by end-intensification with high-dose melphalan and autologous bone marrow transplantation (Protocol HR-2). Because of poor results of HR-2, another high-risk protocol (HR-3) was initiated in January 1985. Patients on HR-3 received 2 cycles of chemotherapy containing vincristine, cyclophosphamide, and doxorubicin followed by local radiation therapy and maintenance chemotherapy. At the end of this therapy, autologous bone marrow transplantation (ABMT) was performed, using a preparatory regimen of total body irradiation and intensive chemotherapy. The 2-year disease-free survival rate was 70% for the standard-risk protocol, 20% for HR-2, and 80% for HR-3. The follow-up on HR-3 is still short, but the results are promising enough to warrant further clinical trials.
Hemoglobin-CC is a relatively uncommon hemoglobinopathy, seen primarily in the black population. These patients usually have a mild clinical course, without significant risk of vasoocclusive crises. There are no routine recommendations for preparation prior to surgery. We present a patient who developed a clinical picture suggestive of major vasoocclusion after cardiac by-pass surgery. In retrospect, these signs appear to be the result of hemodynamic instability and cardiogenic shock instead of vasoocclusion.