Recognition of Pseudomonas pickettii in the clinical laboratory: biochemical characterization of 62 strains

Abstract

Pseudomonas pickettii strains were studied to determine the characteristics essential for their identification in the clinical microbiology laboratory. Preliminary investigations indicated that these glucose-oxidizing, denitrifying, gram-negative rods were quite similar to an unclassified group of clinical isolates designated VA-2. Gas liquid chromatography of trimethylsilyl derivatives of whole cell hydrolysates of P. pickettii and VA-2 strains yielded nearly identical elution profiles. The VA-2 cultures were concluded to be probable strains of P. pickettii. A method is presented for differentiating cultures of P. pickettii from other similar bacteria encountered in clinical specimens.

Association between gentamicin resistance and stress tolerance in water isolates of Ralstonia pickettii and R. mannitolilytica

“…Some species of the genus Ralstonia within the class Betaproteobacteria, in particular, the species Ralstonia pickettii and R. mannitolilytica, are frequently observed in aquatic habitats, specifically in wastewater, potable water, surface water, and mineral water (Becerra-Castro et al 2015;Falcone-Dias et al 2012;Ryan et al 2011;Vaz-Moreira et al 2017). These Ralstonia species are comprised of ubiquitous bacteria that have been found in a wide variety of environments, such as in plastic (Poly Vinyl Chloride) pipes forming biofilms structures, aerospace samples, purified water, saline solutions, skin disinfectants, biological samples, caps of blood culture bottles, or even in human patients in the respiratory tract or the oral cavity (Adley et al 2005;Anderson et al 1990;Boutros et al 2002;Coenye et al 2002;Coman et al 2017;Daxboeck et al 2005; Koenig and Pierson 1997;Kulakov et al 2002;Labarca et al, 1999;Maroye et al 2000;McNeil et al, 1985;Mijnendonckx et al 2013;Riley and Weaver 1975;Ryan et al 2006;Stelzmueller et al, 2006;Verschraegen et al 1985). The ubiquitous character of these bacteria is related to the requirement for minimal nutrient resources and explains the transmission from various sources to humans (Daxboeck et al 2005).…”

“…Although members of R. pickettii and R. mannitolilytica lack major virulence factors, and rarely are reported as causing infection, members of these species have been considered the most pathogenic species of the genus (Vaneechoutte et al 2004). Indeed, nosocomial outbreaks attributed to R. pickettii or R. mannitolilytica have been reported regularly over the last 30 years (Coman et al 2017;De Baere et al, 2001;Fernandez et al, 1996;Khajuria et al 2014;Labarca et al, 1999;Riley and Weaver 1975;Ryan et al 2006;Vaneechoutte et al 2001;Verschraegen et al 1985).…”

Cultural and biochemical characteristics of clinical isolates of unusual colistin-resistant pseudomonads

“…The organisms designated as group Va constitute a heterogeneous collection of oxidase-positive, monopolar, gram-negative rods which fail to fluoresce, to grow on cetrimide, or to attack lysine or arginine, but which oxidize a variety of carboydrates (13). Two distinct varieties are currently recognized (13), and one of these, CDC Va-2, has been given species rank as P. pickettii (11,12). Recently, a denitrifying saprophyte recovered from soil and bearing a biochemical similarity to P. pickettii has been described (2).…”

“…Indicative of such organisms is the currently recognized Center for Disease Control (CDC) Va group, previously regarded as group IVd (4). Two well-delineated biotypes within the Va group have been reported; one of these (CDV Va-2) is seemingly identical to the newly described Pseudomonas pickettii (11,12). However, the variation in ability to produce acid from most carbohydrates suggests that these organisms are heterogeneous and that the group consists of numerous biotypes (13).…”

Factors associated with Pseudomonas pickettii intrinsic contamination of commercial respiratory therapy solutions marketed as sterile

“…Bacterial counts then gradually decreased to 6 CFU/liter at 30 min and to 2 CFU/liter at 60 min. DISCUSSION P. pickettii is an aerobic, nonfermentative, gram-negative bacillus that has been recovered from clinical specimens and from other environmental sources such as water distribution systems (10,15,16,18,21). Correct identification of this organism depends on reactions to a battery of conventional biochemical tests (8,11,(16)(17)(18)23), and accurate identification may not always be possible when an automated system is used (3).…”