TABLE 2.

Diagnostic yields of the different techniques according the type of pneumonia

Specimen	Yielda for indicated type of:							Global diagnostic yieldd
	Bacterial pneumonia		Fungal pneumonia		Mycobacteriosis		Viral pneumonia, ASb
	ASb	OSc	ASb	OSc	ASb	OSc
BAS								23/35 (66)
Culture	12/15 (80)	11/12 (92)	10/11 (91)e	10/11 (91)	1/1	1/1
Gram stain	11/15 (73)	11/12 (92)	9/11 (82)e	9/11 (82)
Ziehl-Neelsen stain					1/1	1/1
BAL								70/134 (52)
Culture	11/18 (61)	7/7 (100)	7/12 (58)e	6/8 (75)	7/8 (87)	2/2 (100)	14/15 (93)
Gram stain	8/18 (44)	5/7 (71)	2/12 (17)e	2/8 (25)
Ziehl-Neelsen stain					3/8 (37.5)	2/2 (100)
GMS stain			22/22 (100)f	10/10 (100)
Viral Ag detection							9/17 (53)
Sputum								38/187 (20)
Culture	20/35 (57)	20/21 (95)g	5/14 (36)e	5/13 (38)	13/15 (87)	13/14 (93)
Ziehl-Neelsen stain					9/15 (60)	9/14 (64)
PSB								14/110 (12)
Culture	8/13 (61)	4/4 (100)	6/12 (50)e	3/4 (75)
Gram stain	5/13 (38)	4/4 (100)	1/12 (8)e	1/4 (25)
Pleural fluid culture	0/3	0/3	0/11e	0/11	1/11 (9)	1/11 (9)		1/11 (9)
Blood culture	15/42 (36)	15/42 (36)	2/16 (13)e	2/16 (13)				17/208 (8)
NPW								3/47 (6)
Culture							3/10 (30)
Viral Ag detection							1/10 (10)
Bacterial serology	0/5	0/5						0/35
Viral serology							1/2 (50)	1/20 (5)
Induced-sputum GMS stain			1/8 (12)f	1/4 (25)				1/56 (2)
L. pneumophila Ag urine	0/28	0/28						0/151

^aTotal number of diagnoses (diagnoses of pneumonia etiology)/total number of specimens fulfilling the criteria for AS or OS (the specimens included in each classification are described in footnotes b and c, respectively. Percentages are in parentheses.

^bAll specimens (AS) from patients with the indicated diagnoses are included.

^cSpecimens not fulfilling the criteria for optimum specimen (OS) quality are excluded.

^dTotal number of diagnoses (including both infectious- and noninfectious-agent etiologies)/total number of specimens collected.

^eCases of filamentous fungi and yeasts.

^fCases of P. carinii.

^gP < 0.05.