**3. Results**


Patient clinical characteristics are summarized in Table 1.

Table 1. Subject's clinical characteristics and symptom changes after irrigations

Each patient underwent 3 colonic irrigations over a period of 2 weeks. Fecal samples were collected before the first colon irrigation and at 1 week after the third irrigation. The relative proportions of bacteria found in the fecal samples of each patient before and after colonic irrigation are shown in Table 2.


Table 2. Continued

The Influence of Colonic Irrigation on Human Intestinal Microbiota 455

This study showed that colonic irrigations are safe in terms of serum electrolytes for subjects with normal renal function and had a positive impact on these subjects' symptoms. However, these irrigations showed no tendency for any effects on the intestinal microbiota. Colonic irrigation was developed at the National Aeronautics and Space Administration and has been used worldwide in the care of allergic and pollen diseases, skin disorders, and constipation. I previously reported that colonic irrigation may induce lymphocyte transmigration from GALT into the circulation, which may improve the function of both the colon and the immune system functions (Uchiyama-Tanaka, 2009). The increase in the lymphocytes was suspected to be the result of lymphocytes transmigrating as intraepithelial lymphocytes from Peyer's patched and lymph nodes around the intestine as a result of

Based on my personal experience, patient symptoms can improve after colonic irrigations. However, it has been proposed that colon irrigations with large volumes of water may obliterate the microbiota and induce electrolyte abnormalities, but no studies support these claims. The results of this study suggests that after 3s colonic irrigations, the composition of the microbiota changes, but there is no tendency for the changes in the bacterial

Colonic irrigations are different from enemas for the following reasons: (a) they are not selfadministered, but are administered by a professionally trained person; and (b) they are administered using a device that controls water flow and infuses the entire colon with water, in contrast to the more limited infusion of warm filtered water into the rectum. The water circulates throughout the colon and removes its contents while the patient lies on a bed. The temperature and pressure of water are closely monitored and regulated during a series of fills and releases to aid colonic peristalsis. Because this method involves a closed system, the waste materials are removed without any unpleasant odor or discomfort, which

The intestine is an important site of local immunity and nutrition (Iiai et al., 2002). It is a major site of extrathymic T cell differentiation, and numerous activated and quiescent lymphocytes are produced within GALT. The very important role of the intestine, as a part of the immune system is due to the intestinal microbiota. Thus, it has been speculated in peoplewho suffer from constipation and who harbor fecal residues, the intestine may have a

The intestinal epithelium is the first line of defense system to encounter intestinal pathogens and dietary antigens. It has been speculated that when the intestine is filled with feces, there may be a reduced function of this immune system caused by toxins leaking from the gut, in addition to bacterial translocation from the gut to the systemic circulation caused by a breakdown of the intestinal wall. This breakdown can be caused by a variety of injuries to

It has been reported that increased gut permeability and bacterial translocation play a role in multiple organ failure (MOF: Swank & Deitch, 1996). Failure of the gut barrier is central to the hypothesis that toxins escaping from the gut lumen contribute to the activation of a host's immune inflammatory defense mechanisms, which subsequently leads to auto-

diminished function in the immune system (Alveres, 2001, 1924).

**4. Discussion** 

components.

irrigation and abdominal massage.

are usually associated with enemas.

the body at further locations far from the gut.


No 1-10: Patients in Table 1. b: Before colonic irrigations. a: After 3 times colonic irrigations

Table 2. The changes in the fecal microbiota between prior to and after 3 clonic irrigations

There were no significant differences in the overall quantities of fecal bacteria in samples collected before and after irrigations. There was also no tendency for changes int the proportions of Lactobacillales and *Bifidobacterium* and *Clostridium* subclusters. The proportions of these bacterial orders are shown in Table 3.


Table 3. The mean changes in the microbiota between prior to and after 3 colonic irrigations

According to Collins et al. (1994), *Clostridium* clusters and subclusters cannot revide the unknown pole in intestine. For example, *Faecalibacterium prausnitzil* is an important bacteria as butyrate-producing bacterium in *Clostridium* cluster IV. In contrast, *Clostridium perfringens* is a well known as harmful bacterium in *Clostridium* cluster I. Lactobacillales and *Bifidobacterium* are considered to be healthy, beneficial fecal bacteria. In this study, beneficial bacteria decreased in some patients. Serum electrolytes after irrigations (sodium, potassium, and chlorine) exhibited no significant changes from their values before irrigation (data not shown). Patient symptoms were improved after irrigations (Table 1), and they did not experience any difficulties.
