Table 1.

Histomorphological and Immunohistochemical Characteristics of Inflammatory and Vascular Lesions in Children with AIDS-Associated Lymphocytic Interstitial Pneumonia

Case	LIP	Mϕ ISH/IHC	VCAM-1	Arteriopathy
				Vasculitis	Initimal fibrosis	Fragmentation of elastic tissue	Fibrosis and/or calcification of media
1	+++*†	++++/++++	8	+	+	+	−
2	+++*	++++/++++	6	+	+	+	−
3	++	++/+	6	−	−	−	−
4	++‡	+/+	2	−	−	−	−
5	++	+/−	3	−	−	−	−
6	+++*	+++/+++	8	+	+	+	+

Specimens were obtained from W. Travis, National Institutes of Health, Bethesda, MD, and S. Brodie, Department of Laboratory Medicine, University of Washington, Seattle, WA.

LIP was scored as follows: +, multifocal interstitial leukocytes; ++, multifocal and intermittent confluent areas of leukocyte infiltration; +++, confluent areas of alveolar septal thickening with leukocytes and lymphocyte aggregates with or without germinal centers. ISH/IHC, in situ hybridization for HIV mRNA/immunohistochemistry for HIV gag p24 protein. Results represent an average of 10 microscopic fields (10×) as follows: −, no positive cells; +, 1 to 5 positive cells; ++, 5 to 10 positive cells; +++, 10 to 15 positive cells; ++++, greater than 15 positive cells. For VCAM-1, immunoreactive vessels were assigned scores as follows: 0, no vessels; 1, 1 to 4 vessels; 2, 5 to 10 vessels; 3, 11 to 15 vessels; 4, 16 to 20 vessels; 5, >20 vessels. Staining intensity was scored as follows: 0, no reactivity; 1, faint; 2, moderate, with or without 4 vessels being intense; 3, intense staining of >4 pulmonary vessels. The sum of these two values was then used as the final score, which had a theoretical range from 0 to 8. Arteriopathy was characterized by special stains for inflammation within the vascular wall (vasculitis), intimal fibrosis, fragmentation of elastic tissue and/or fibrosis and calcification of media. These categories were scored as positive (+) or negative (−).

* Concurrent EBV.

^† Concurrent KSHV.

^‡ Concurrent human CMV.