Gluconobacter as Well as Asaia Species, Newly Emerging Opportunistic Human Pathogens among Acetic Acid Bacteria

Abstract

Acetic acid bacteria (AAB) are broadly used in industrial food processing. Among them, members of the genera Asaia, Acetobacter, and Granulibacter were recently reported to be human opportunistic pathogens. We isolated AAB from clinical samples from three patients and describe here the clinical and bacteriological features of these cases. We report for the first time (i) the isolation of a Gluconobacter sp. from human clinical samples; (ii) the successive isolation of different AAB, i.e., an Asaia sp. and two unrelated Gluconobacter spp., from a cystic fibrosis patient; and (iii) persistent colonization of the respiratory tract by a Gluconobacter sp. in this patient. We reviewed the main clinical features associated with AAB isolation identified in the 10 documented reports currently available in the literature. Albeit rare, infections as well as colonization with AAB are increasingly reported in patients with underlying chronic diseases and/or indwelling devices. Clinicians as well as medical microbiologists should be aware of these unusual opportunistic pathogens, which are difficult to detect during standard medical microbiological investigations and which are multiresistant to antimicrobial agents. Molecular methods are required for identification of genera of AAB, but the results may remain inconclusive for identification to the species level.

Innate Immunity against Granulibacter bethesdensis, an Emerging Gram-Negative Bacterial Pathogen

“…G. bethesdensis has since been cultured from at least 5 patients with CGD in the United States (15,16) and 1 in Spain (23), justifying its classification as an emerging pathogen in this primary immunodeficiency. Although the bacterial family to which G. bethesdensis belongs-the Acetobacteraceae-was previously considered nonpathogenic in humans, case reports of human infections by other members of this family are being published with increasing frequency (1,2,5,6,9,12,17,22,26,27). Common elements of infection by these other Acetobacteraceae species appear to include intravenous drug administration (for either medicinal or recreational purposes), organ transplant, or chronic medical problems requiring dialysis.…”

Serologic Reactivity to the Emerging Pathogen Granulibacter bethesdensis

“…molecular evidence documented the presence of Acetobacteraceae species on the forearm of one individual [19]. Increasingly, infections from other Acetobacteraceae species have been reported in some immunocompromised patients [14][15][16][17]20]. Six culture-positive cases of G. bethesdensis infection in CGD, a disease with a molecularly and cellularly defined immune defect, provides a unique opportunity to dissect previously unrecognized host and pathogen determinants of disease.…”

“…Acetobacteraceae species are found worldwide, particularly in tropical regions [11][12][13], and some are increasingly associated with infection of immunocompromised patients [14][15][16][17]. In CGD, the causative pathogen of an infection, including lymphadenitis, is frequently not found despite response to empirical therapy.…”

Acetic Acid Bacteria – Taxonomy, Ecology, and Industrial Application

“…Opisano także kilka przypadków bakteriemii wywołanej przez bakterie octowe z rodzaju Asaia u osób dorosłych, przewlekle chorych, poddawanych okresowym dializom oraz u dzieci chorych na kardiomiopatię lub choroby nowotworowe. Szczepy oportunistyczne izolowane z materiału klinicznego charakteryzowały się zróżnicowaną opornością na antybiotyki: doksycyklinę, gentamycynę lub tetracyklinę [1,42].…”