The colonization of solid PVC surfaces and the acquisition of resistance to germicides by water micro-organisms.

Six common water bacteria were examined for their ability to colonize polyvinyl chloride (PVC) surfaces, survive various germicidal treatment, and re-establish themselves in sterile distilled water (SDW). For each test, two 30.4 cm PVC pipes attached to a 90 degrees PVC elbow were filled with 600 ml of distilled water inoculated with either Pseudomonas aeruginosa, Ps. cepacia, Ps. mesophilica, Acinetobacter anitratus, Mycobacterium chelonae or M. chelonae var. abscessus. After 8 weeks contaminated water was removed and the pipes were exposed to 600 ml of 1:213 iodophor disinfectant (ID), 1:128 phenolic detergent (P), 1:256 quaternary ammonium compound (QA), stock iodophor antiseptic (IA), 2% formaldehyde (F), 10-15 ppm free chlorine (C), 2% glutaraldehyde (G) and 70% ethanol (E). These germicides were periodically sampled, neutralized and examined for surviving organisms. After exposure for 7 d the germicides were removed and each pipe was refilled with SDW. This was assayed at 7 d intervals to determine microbial re-establishment. Samples were removed during microbial conditioning and examined by scanning electron microscopy (SEM). Pseudomonads were isolated directly from ID, QA, C, P and F, and mycobacteria from QA, IA, ID, P, G, C and F. Pseudomonas aeruginosa and Ps. cepacia survived in PVC pipes after 7 d of exposure to P, ID and C; Ps. mesophilica, after C and ID; and both mycobacteria, after C. SEM examination of PVC remnants revealed bacterial attachment and formation of extracellular material with embedded cells. These studies show that common water bacteria can attach and colonize the interior surface of PVC pipes and develop significant resistance to the action of certain germicides.(ABSTRACT TRUNCATED AT 250 WORDS)

Infections and pseudoinfections due to povidone-iodine solution contaminated with Pseudomonas cepacia.

In 1989 we investigated the first instance of Pseudomonas cepacia infections due to intrinsic contamination of a povidone-iodine product. Six patients in a Texas pediatric facility had P. cepacia infection or pseudoinfection (three, peritonitis; one, pseudoperitonitis; and two, pseudobacteremia). Epidemiological studies showed one risk factor for infection of peritoneal fluid with P. cepacia: performance of peritoneal dialysis in the dialysis unit with use of one lot of povidone-iodine later found to be intrinsically contaminated (4/5 vs. 0/16, P = .001). Blood cultures yielded P. cepacia after nurses wiped the tops of blood culture bottles with the povidone-iodine solution before inoculation. P. cepacia was cultured from three povidone-iodine containers used at the hospital and from four containers of the same lot obtained from other health-care facilities in Texas and California. Isolates from patients and the povidone-iodine had similar antibiograms, identical plasmid profiles, and identical DNA banding patterns on the basis of results of ribonucleotide typing. This investigation demonstrates that intrinsic contamination of povidone-iodine solution with P. cepacia can result in infections in addition to colonization and/or pseudoinfection.

Serratia marcescens surgical wound infection following breast reconstruction.

Surgical wound infections due to gram-negative bacilli have been rarely reported following breast implant surgery. From April to November 1989, four patients from one plastic surgeon's practice developed Serratia marcescens surgical wound infection (SWI) following breast reconstruction procedures with implantation of six expandable mammary implants. All six implants were removed for unabated S. marcescens SWI. Symptoms developed 13-161 days (median, 66 days) after surgery. When compared with nonexpandable silicone breast implants used during the period November 1, 1988, to October 31, 1989, expandable implants were associated with a greater risk of S. marcescens SWI (4/10 versus 0/11 patients, p = 0.04). Epidemiologic studies revealed that infection was associated with saline expansion of the implants performed in the surgeon's office. S. marcescens was cultured from a bag of commercial saline used on at least two of the four patients with SWI; the isolate from the saline and the three available patient isolates had identical serotype (O-undetermined:H4) and antimicrobial susceptibility patterns. Review of office procedures revealed that hands were not routinely washed before and aseptic technique was not used during the expansion procedure. Cultures of unopened bags of saline and an unused expandable implant were sterile. We hypothesize that multiple use of saline bags and nonsterile expansion technique extrinsically contaminated saline solutions and resulted in implant and/or surgical site infection. This investigation underscores the importance of avoiding multiple use of solutions intended for single use and of using aseptic technique when manipulating prosthetic devices.

Investigations of intrinsic Pseudomonas cepacia contamination in commercially manufactured povidone-iodine.

OBJECTIVE: Laboratory investigations were initiated with a povidone-iodine antiseptic solution that was intrinsically contaminated with Pseudomonas cepacia. These investigations were helpful in understanding the microbicidal and chemical properties of iodophor solutions and the mechanism by which P cepacia can survive in iodine-containing antiseptics. DESIGN: Included in these studies were: prolonged survival of P cepacia; available and free iodine determinations; microbial challenge studies; and scanning electron microscopic examination of contaminated antiseptic. RESULTS: P cepacia survived in this iodophor antiseptic up to 68 weeks from the date of manufacture. A uniform concentration of 1% available iodine was found in all lots of povidone-iodine tested as specified on the product label, but free iodine (I2) values varied greatly. Low free iodine levels of 0.23 to 0.46 ppm were associated with the contaminated lot of povidone-iodine. Solutions of povidone-iodine with varying levels of free iodine were rapidly microbicidal when challenged with cells of P cepacia derived from culture broth and washed or adapted to growth in water. P cepacia cells taken directly from contaminated povidone-iodine survived for significantly longer periods of time. Large numbers of P cepacia were found embedded in extracellular material and among strands of glycocalyx between cells as shown by scanning electron microscopy. CONCLUSIONS: The physical thickness of cellular and extracellular material that forms on surfaces could protect embedded organisms from the microbicidal action of disinfectants and antiseptics and subsequently allow for extended microbial survival times. Manufacturers should be aware that distribution piping surfaces colonized with bacteria may be a source of product contamination and resistant organisms.

Prolonged survival of Pseudomonas cepacia in commercially manufactured povidone-iodine.

Pseudomonas cepacia organisms were recently recovered from a povidone-iodine antiseptic solution. During the subsequent investigation, laboratory studies were initiated to determine the survival time of these organisms in the iodophor solution, which contains 1% titratable iodine. The solution was sampled weekly upon receipt in our laboratory, and P. cepacia was subsequently recovered through 29 weeks of sampling. Current laboratory data and lot production date information from the manufacturer indicate that P. cepacia survived for up to 68 weeks from the time of manufacture. Scanning electron microscopic examination of contaminated solution demonstrated bacterial cells embedded in extracellular material.