Lobar pneumonia is caused predominantly by:: (A) Klebsiella pneumoniae, (B) Staphylococcus pyogenes, (C) Haemophilus influenzae, (D) Streptococcus pneumoniae
Answer is D. Most cases of lobar pneumonia are caused by S. pneumoniae (reclassification of the pneumococcus). Streptococcal or pneumococcal pneumonia involves one or more lobes and is often seen in alcoholics or debilitated persons.