To  the editor:

Asepsis  is essential  in automated  peritoneal  dialysis  to  prevent infectious complications.

Patients  undergoing  automated  peritoneal  dialysis  (APD)  usually  have  a lower risk of peritonitis as compared to those  subject  to  CAPD.1-4 However, drainage fluid is stored in an open container at room temperature. This container is washed daily with diluted sodium hypochlorite (bleach).

OBJECTIVES

To  determine  the  contamination  status of  the  drainage  fluid  collected  in  the container.

To  assess whether  this  fluid  storage method  involves  an  infection  risk  for patients.

To  ascertain whether  the  usual method for disinfecting containers is effective.

MATERIALS AND METHODS

Samples  were  taken  from  patients  on APD at our unit for Gram staining and microbiological  cultures  in  standard and  blood  culture  media. A manually drained  sample  was  collected  in  all cases to be used as control.

In  addition,  serial  samples  were taken from a patient subgroup to see the type of flora and whether this was sensitive to routine disinfection.

The drainage container was disinfected with diluted bleach.

RESULTS

Nine cases of patients on APD, whose containers were cleaned daily, were studied.

The fluid in the container was contaminated by a germ in 5 cases (55.5%), by 2 germs in 2 cases (22.2%), and by more  than  2  germs  in  another  2  cases (22.2%).

Ten  different  germs  were  identified out  of  the  total  15  germs  found.  Of these,  60%  were  Gram-negative  and 40% Gram-positive organisms.

The  container  fluid had Gram-negative  germs  in  5  cases,  Gram-positive germs  in  3  cases,  and  both  types  of germs in one case.

Most common germs  included Serratia marcescens, Pseudomonas putida, Streptococcus agalactiae, Enterobacter cloacae,  and  Staphylococcus epidermidis, all of them identified twice, while all other organisms only occurred once.

Enterobacteriaceae accounted for more than 40% of germs, while the remaining organisms  were  mainly  environmental germs proliferating at room temperature.

Serial samples were taken in 4 cases. When  samples  were  taken  after  24 hours,  recurrence  of  some  germ  was seen in 50% of cases.

The  control  culture was  negative  in all cases.

CONCLUSIONS

All fluids in the containers were contaminated.

Forty  percent  of  contaminants were enterobacteriaceae.

It  is  questionable  that  bleach  removes contaminating germs.

Neither the container nor contaminated  drainage  fluid  caused  infection  in patients.

The container is a safe but not completely aseptic model.