A sputum sample was brought to the laboratory for analysis. Gram stain
revealed the following: rare epithelial cells, 8 to 10
polymorphonu-clear leukocytes per high-power field, and pleomorphic
Gram-negative rods. As the laboratory consultant, which of the following
interpretations should you make?
A. The sputum specimen is too contaminated by saliva to be useful
B. The patient has pneumococcal pneumonia
C. The patient has Vincent’s disease
D. The appearance of the sputum is suggestive of Haemophilus pneumonia
A. The sputum specimen is too contaminated by saliva to be useful
B. The patient has pneumococcal pneumonia
C. The patient has Vincent’s disease
D. The appearance of the sputum is suggestive of Haemophilus pneumonia
Ans. D.
Many sputum specimens are cultured
unnecessarily. Sputum is often contaminated with saliva or is almost totally
made up of saliva. These specimens rarely reveal the cause of the patient’s
respiratory problem and may provide laboratory information that is harmful. The
sputum in question appears to be a good specimen. The pleomorphic Gram-negative
rods are suggestive of Haemophilus, but culture of the secretions is necessary.
