Normal sputum: This slide shows typical buccal squamous epithelial cells which are much larger than PMN and take up most of the field in a high power view. This cell is covered with chains of Gram positive cocci typical of normal oral flora such as peptostreptococci. (oil immersion, 1000x)



Moraxella catarrhalis.  A large number of Gram negative (red) cocci are seen and many appear to be attaching to or residing within the PMNs. Some physicians confuse these organisms with the Gram negative coccobacillary



Hemophilus influenzae pneumonia demonstrating the typical Gram negative coccobacillary forms. Because of the red background produced by the Gram stain method, these organisms can be difficult to see. (oil immersion, 1000x)




Gram stain of the sputum from a patient with Staphylococcus aureus pneumonia demonstrating clusters of Gram positive cocci some of which are associated with the PMNs. (oil immersion, 1000x)



 Klebsiella pneumoniae pneumonia demonstrating Gram negative bacillary organisms. (oil immersion, 1000x)



Gram stain of the sputum from a patient with a hemorrhagic pneumonia and the sputum grew Pseudomonas aeruginosa. The gram negative bacillary organisms typical of P. aeruginosa are seen mixed with fragments of red blood cells in this specimen. (oil immersion, 1000x)