Differential cell count and lymphocyte subsets in bronchoalveolar lavage during pneumonia with and without peripheral neutropenia

Abstract

One hundred immunocompromised HIV negative patients with microbiologically positive pneumonia underwent bronchoalveolar lavage (BAL) studies. Thirty cases showed peripheral neutropenia (< 1000 neutrophils/microL), 70 did not. The total cell number in BAL, the differential cell counts, and the lymphocyte subsets (CD4, CD8, CD19, CD57) were measured. Patients with pneumonia and normal or elevated peripheral neutrophils had a significantly increased total number of cells in BAL compared to patients with peripheral neutropenia (3.2 +/- 2 vs 1.3 +/- 0.6 x 10(5) cells/ml2 lavage fluid, p < 0.01). Ninety percent of the BAL differential cell counts obtained in patients exceeding 1000 neutrophils/microL showed a lymphocytic and/or neutrophilic alveolitis, whereas only 54% of patients with peripheral neutropenia displayed abnormal counts (p < 0.01). Yet the typical pattern of neutrophilic alveolitis was found more often for peripheral neutrophil counts over 1000/microL with high significance (p < 0.0001). Abnormal BAL cell patterns for neutropenic patients uniformly showed a lymphocytic alveolitis, only 10% additionally conformed with the pattern of neutrophilic alveolitis. Patients with pneumonia with and without peripheral neutropenia had similar findings in BAL lymphocyte subsets and exhibited a reduced CD4/CD8 ratio compared to controls (p < 0.05). The high susceptibility of severe neutropenic patients to pulmonary, especially fungal infections may be explained by the local lack of neutrophils.

The Anti-Pseudomonas aeruginosa Antibody Panobacumab Is Efficacious on Acute Pneumonia in Neutropenic Mice and Has Additive Effects with Meropenem

“…aeruginosa strain, as no positive effect was noticed against an O1-LPS strain. In the CP-induced neutropenia model (100mg/kg), the number of granulocytes was reduced about 80% as compared to untreated mice, which is similar to the observed massive leucopenia present in hematopoietic transplantation recipient [25,26] or HIV patients [27]. Despite severe immune suppression, the treatment with Panobacumab resulted in a reduction of bacterial load and inflammation in the lung, indicating that reduced leukocyte numbers might still be sufficient to mediate bacterial clearance after opsonization by Panobacumab.…”

Deactivation of Alveolar Macrophages in Septic Neutropenic ARDS*

“…In septic neutropenic patients with infectious pneumonia, BAL is used predominantly to recover alveolar macrophages (AMs). 11,12 Activated AMs can release a wide variety of mediators, most of them capable of damaging the lung alveolar-capillary barrier. [13][14][15][16] Schwartz et al 17 showed in ARDS patients an increased in vivo activation of the nuclear transcriptional regulatory factor nuclear factor B in AMs, which may contribute to the increased expression of various cytokines.…”