Evidence of both pulmonary fibrosis and bone marrow failure in individuals with mutant telomerase genes. (A-B) Representative CAT scan images showing typical peripheral honeycombing pattern in 2 individuals with idiopathic pulmonary fibrosis and pancytopenia. Both individuals had biopsy confirmation of the usual interstitial pneumonia. The scans are from individuals in families 2 and 6. (C) CAT scan image of the proband of family 7, who developed pulmonary fibrosis after bone marrow transplantation for AA. Biopsy confirmed nonspecific interstitial pneumonia. (D) For the 3 individuals with images shown, the percentage of bone marrow CD34⁺ cells by flow cytometry was decreased in the setting of pancytopenia, macrocytosis, and hypocellular/aplastic marrow. The 95% confidence interval for CD34⁺ percentage is 0.4%-1.8%.