Evaluation of concentration and storage effects of mitomycin C in the diagnosis of Fanconi anemia among idiopatic aplastic anemia patients.

BACKGROUND: Fanconi anemia (FA) is a rare autosomal recessive genetic disorder that shows an increased sensitivity to the intercalating agents such as mytomycin C (MMC), measured as chromosomal aberrations. This study was conducted to differentiate between FA and “idiopathic” aplastic anemia on the basis of induced chromosomal breakage study with MMC. MATERIALS AND METHODS: MMC stress tests in different final concentrations of 20 and 50 ng/ml of MMC were conducted on peripheral blood lymphocytes from 32 patients with aplastic anemia and 13 healthy controls. Fifty nanograms per milliliter of MMC from old, fresh and frozen stocks was used to check the sensitivity of diagnosis on FA-diagnosed patients. Statistical analysis was used for the assessment of aberrations, including chromatid and chromosome breaks and exchanges. RESULTS: Eight patients (25%) with a very high percentage of chromosomal breakage were diagnosed as FA on the basis of the chromosomal breakage study. Six of these patients exhibited congenital anomalies at presentation, while another two lacked such anomalies or had minor physical problems. Freshly made MMC has shown more sensitivity to detect FA patients compared with frozen or 1-week-old MMC stock. CONCLUSIONS: The study indicates that freshly made MMC stress test provides an unequivocal means of differentiation between FA and “idiopathic” aplastic anemia. Further, the study, the first of its kind from Iran, stresses on the need for conducting this test in all aplastic anemia cases, even those without congenital anomalies, for accurate and timely diagnosis of FA to implement appropriate therapy.

Differentiation of Fanconi anemia from idiopathic aplastic anemia by induced chromosomal breakage study using mitomycin-C (MMC).

This study was conducted to differentiate between Fanconi anemia (FA) and "idiopathic" aplastic anemia on the basis of induced chromosomal breakage study with mitomycin C (MMC). MMC-stress test was conducted on peripheral blood lymphocytes from 29 patients with aplastic anemia. Ten patients with very high percentage of chromosomal breakage and four patients exhibiting somatic mosaicism were diagnosed as FA on the basis of chromosomal breakage study. Six of these patients exhibited congenital anomalies at presentation while another eight lacked such anomalies or had minor physical problems.The present study illustrates that MMC stress test provides an unequivocal means of differentiation between Fanconi anemia and 'idiopathic' aplastic anemia. Further, the study, first of its kind from India, stresses on the need for conducting this test in all aplastic anemia cases, even those without congenital anomalies, for accurate and timely diagnosis of Fanconi anemia to implement appropriate therapy.