Karyotype study of blood lymphocytes in sarcoidosis

Among 31 patients presenting with pulmonary sarcoidosis, two had abnormalities of their blood lymphocyte karyotypes. The karyotype of the first patient showed an initially high percentage of non-specifically broken chromosomes. The second patient, who had been treated with azathioprine (AZ) one year previously, had an apparently balanced translocation 46 XX, t (11; 11) (p 12, p 14) in blood T lymphocytes but not in skin fibroblast culture. Various hypotheses can be discussed to explain this translocation: a direct toxic effect of AZ or a genomic abnormality depending upon sarcoidosis and possibly revealed by AZ. It is important to note that this translocation concerned a region of the short arm of chromosome 11, where Harvey ras I and parathormone genes have been located.