The lungs, spleen and liver were removed. One portion of each organ was homogenized in Middlebrook 7H9 broth to determine the mycobacterial load after serial dilutions and plating on Middlebrook 7H10 at 37 uC under a 5% CO2 atmosphere for 10 days. The remaining portion of each organ was fixed with 10% formalin for histopathological analyses