Table 2.

Causes of Proven Bacterial Lung Infections in Postmortem Tissue Samples of Patients With COVID-19

Direct Visualization of Bacteria in Tissue, No.	Positive Culture Results for Bacteria, No.	Positive PCR Results for Bacteria, No.
Bacteria NOS, 24	Acinetobacter baumannii, 12	Streptoococcus spp., 3
	Staphylococcus aureus, 10
	Pseudomonas aeruginosa, 10
	Klebsiella pneumoniae, 8
	Escherichia coli, 3
	Stenotrophomonas maltophilia, 2
	Enterococcus spp., 2
	Proteus mirabilis, 1
	Enterobacter cloacae, 1
	Coagulase-negative Staphylococcus, 1
	“Mixed flora,” 3a

Abbreviations: COVID-19, coronavirus disease 2019; NOS, not otherwise specified; PCR, polymerase chain reaction.

^a“Mixed flora” typically are ascribed to postmortem contamination; these cases were not included as potential superinfections in our series.