Aplastic anemia diagnosis

Jolles and Joll s (1984) have reviewed the use of lysozyme as a marker in certain diseases. Serum lysozyme levels have been used extensively in the diagnosis of leukemias. Jolles and Jolles discussed some of the reasons for increased and decreased serum levels in various diseases, such as acute or chronic granulocytic leukemia, myeloid metaplasia, and aplastic anemia, and decreased levels in tears in keratoconjunctivitis. They have also considered the interaction of lysozyme with sulfated proteoglycans and its role in the calcification of epiphyseal cartilage. It is to be expected that such studies will yield valuable information, giving rise to further applications in the future (see also Fett et al., 1985). Lysozyme will continue, of course, to serve as a prototype protein for the investigation of the specificity of immune recognition. 

Eleven cases of acetazolamide-associated aplastic anemia were reported in Sweden during a 17-year period (15). The median dose was 500 mg/day and the median duration of therapy was 3 (2-71) months. Ten of the eleven patients died within 8 weeks of diagnosis. The relative risk of aplastic anemia with acetazolamide was 13.3 (95% Cl = 6.8,25) and the estimated frequency was 1 in 18 000. These findings suggest that acetazolamide is associated with a substantially increased risk of aplastic anemia. 

In a prospective, multicenter, cohort study of 113 patients with aplastic anemia under 18 years of age, 12 developed myelodysplastic syndrome after a median of 37 months after the diagnosis of aplastic anemia and four others developed other cytogenetic clonal changes, of which the most common abnormality was monosomy 7 (80). From a multivariate analysis, G-CSF treatment duration and non-response to immunosuppressive therapy at 6 months were statistically significant risk factors for the development of myelodysplastic syndrome. The... 

In a case-control surveillance of agranulocytosis and aplastic anemia conducted in the metropolitan area of Barcelona, where 178 cases of aplastic anemia were identified, nifedipine was associated with a significant relative risk of aplastic anemia, which translates into an absolute risk of 1.2 per patient-year. Among the 178 patients, 147 were interviewed and compared with 1295 controls. Six cases (4.1%) and 11 controls (0.8%) had been exposed to nifedipine during the window period, as aU of them had taken nifedipine for at least 7 months. The multivariate odds ratio was 4.6 (95% Cl = 1.5,15). AU six died within 5 months of diagnosis. The authors concluded that the risk of aplastic anemia associated with nifedipine is of a similar magnitude to that associated with chloramphenicol (1.7 per 100 000 patients) and that associated with phenylbutazone (2.2 per 100 000 patients) (21). 

E. The correct diagnosis is thalassemia minor because the patient had been asymptomatic until age 7 years. If he had thalassemia major or Cooley anemia, he would have exhibited symptoms as early as his first birthday. Pernicious anemia leads to a macrocytic or megaloblastic anemia, whereas aplastic anemia is characterized by normal sized erythrocytes. 

Perchlorate, which competitively inhibits the uptake of iodide, has been used in both diagnosis and treatment of thyroid disease. In continental Europe, perchlorate has been used for surgical preparation and in the long-term treatment of thyrotoxicosis. In the United States, the use of perchlorate was drastically curtailed after aplastic anemia and severe renal damage were reported following its use. 

No laboratory tools are presently available to identify the drug responsible for triggering aplastic anemia in an individual case. Accordingly, the diagnosis is based on the finding of pancytopenia in the peripheral blood and deficiency of myeloid and erythroid precursor cells in the bone marrow. 

IV. Diagnosis of benzene poisoning is based on a history of exposure and typical clinical findings. With chronic hematologic toxicity, erythrocyte, leukocyte, and thrombocyte counts may first increase and then decrease before the onset of aplastic anemia. 

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