Impaired bactericidal activity of PMN from two brothers with necrotizing ulcerative gingivo-periodontitis

Abstract

The purpose of this study was to investigate the pathogenesis of necrotizing ulcerative gingivo-periodontitis (ANUP) diagnosed in two brothers, age 9 (ANUP1) and 14 (ANUP2) from rural Egypt. Complete blood count, differential and blood chemistry were within normal limits for both brothers and they were not malnourished. The phagocytosis and killing function of their polymorphonuclear leukocytes (PMN) towards four bacterial species were assessed using a fluorochrome microassay. The selection of bacterial species was based on preliminary microbiological results in early onset periodontitis in Egypt. Fluorochrome-labeled Prevotella intermedia, Peptostreptococcus micros, Campylobacter rectus, and Porphyromonas gingivalis were pre-opsonized with ANUP serum and added to PMN from both ANUP patients, as well as PMN from three sex-matched and two sex- and age-matched healthy Egyptian control (CTL) subjects. We found significant depressions (P < 0.05) in PMN phagocytosis and killing of C. rectus and P. intermedia by ANUP1 and ANUP2, when compared to all CTL PMN. An assessment of the Gram-negative subgingival microflora present in both ANUP patients (in colony forming unit percent of total CFU recovered) (CFU %) revealed the presence of P. intermedia (ANUP1, 41.7 CFU %; ANUP2, 14.8 CFU %), Fusobacterium nucleatum (ANUP1, 3.6 CFU %; ANUP2, 48.1 CFU %), and Veillonella spp. (ANUP1, 18.2 CFU %; ANUP2, 18.5 CFU %). Spirochetes were also observed in cytocentrifuged, Gram-stained plaque from both ANUP patients. The predominant Gram-positive bacterial species recovered from both NUG1 and NUG2 was Streptococcus morbillorum.