Microbiological analyses of water from hemodialysis services in São Luís, Maranhão, Brazil

Abstract

Rigorous control of water quality in hemodialysis services is extremely important in order to guarantee a better quality of life of the patients submitted to this treatment. The lack of adequate water monitoring has caused the death of various patients in the past. The objective of the present study was to determine the physicochemical and bacteriological characteristics of water used by hemodialysis services in hospitals of the city of São Luís, Maranhão, Brazil. Bacteriological analyses included the membrane filter method for the determination of total coliform bacteria, the Cult-Dipcombi-TTC-agar method for heterotrophic bacteria and the limulus amebocyte lysate method for the determination of endotoxins. Eighteen water samples obtained from three hospital units, six samples per hemodialysis service, collected directly at the pre-and posttreatment points, were analyzed. Microorganisms were detected in the water used by the hemodialysis services in two of the three hospital units (B and C) studied. No contamination with heterotrophic bacteria was observed in pretreatment samples, while endotoxin production was detected in 100% of the samples. In post-treatment samples, heterotrophic bacteria were detected in 66.6% of the samples and endotoxins in 33.3%. The microorganisms identified in unit B were Burkholderia cepacia, Alcaligenes xylosoxidans, Pseudomonas aeruginosa and Stenotrophomonas maltophilia. In unit C Flavimonas oryzihabitans, Ralstonia pickettii and Burkholderia cepacia were identified. A significant correlation was observed between the presence of endotoxins and the physicochemical characteristics of water such as turbidity and conductivity. These data indicate that two of the three hospital units studied should revise the control of their hemodialysis water system.

Prevent infection linked to the dialysis water in a hemodialysis center in Fez city (Morocco)

“…We isolated genus Pseudomonas at 52.8% in agreement with other authors [21–23]. These bacteria are able to grow rapidly even in sterile water and dialysis fluids.…”

Microbiological contamination of a hemodialysis center water distribution system

“…Other species found in the water from the machines, in order of decreasing frequency, were: 13 P. aeruginosa, eight S. epidermidis and P. stutzeri, two S. maltophilia and K. pneumoniae and one B. cereus, P. putida and F. odoratum. LIMA et al 23 reported the isolation of S. maltophilia and B. cepacia in water samples taken directly from points before and after water treatment and from the kidney machines.…”

Enumeration of heterotrophic bacteria in water for dialysis: comparison of the efficiency of Reasoner'2 agar and plate count agar

“…They are exposed to approximately 120L of treated water in each session (4, 12, 16, 18, 22, 23). Water is separated from the blood of the patient by a semipermeable membrane, which may enable direct access of contaminants that might be present in the water (6, 9, 10, 11, 22).…”

“…Water is separated from the blood of the patient by a semipermeable membrane, which may enable direct access of contaminants that might be present in the water (6, 9, 10, 11, 22). Monitoring and maintenance of water treatment systems are important to assure its chemical and microbiological quality and to prevent additional risks to the patients (4, 6, 9, 10, 11, 12, 14, 15, 16, 18, 22, 23). …”

“…Microorganisms may grow very quickly in water and dialysis fluids, and the development of biofilms enables their persistence in the system, increasing the risk of contamination (3, 4, 6, 9, 10, 12, 13, 15, 16, 18, 22). The intact membrane of the dialysis machine should prevent the contamination of the blood with bacteria from the dialysis fluid.…”