Slide 2. Anaerobic lung infection
The presence of many neutrophils and the absence of epithelial cells confirm that this is a good specimen. Both gram-negative and
gram-positive bacilli and cocci are abundant, but no single type clearly predominates. In a patient with parenchymal pulmonary
infection, such a combination of bacteria suggests that the patient has aspirated oropharyngeal organisms into the lung. Many of the bacteria are probably anaerobes, and the patient may have an anaerobic or mixed aerobic-anaerobic pneumonia or lung abscess. Foul-smelling sputum, produced in about half of patients with anaerobic pulmonary infections, is a clue for clinicians and microbiologists.