Do Antibiotics Influence IBS? TO THE EDITOR: In the January issue, Maxwell et al. (1) describe an intriguing relationship between the use of anti- biotics and the development of functional bowel symptoms likened to irritable bowel syndrome (IBS). They determined that in their cohort of subjects, 4 months after the use of antibiotics, there was an increased incidence of functional GI symptoms relative to controls. There are, however, some concerns with the study, and the authors may have overlooked other interpretations of their data. First, the authors provide background to suggest that when infectious diarrhea is treated with antibiotics, the incidence of IBS symptoms is higher (82%) than in controls (68%), based on a study by Gwee et al. (2). What is not adequately quoted is that this difference was not significant and that it likely represented a more severe infectious illness in the IBS group. In fact, the reported degree of diarrhea and abdominal pain during the infectious illness was higher among those subjects who ultimately developed IBS and likely determined the in- creased (albeit not significantly) level of antibiotic use. Another concern about Maxwell and colleagues’ article is the timing of their questionnaire (1). Clearly, it was first administered after the subjects had already received the antibiotics. Although there appeared to be a similar prean- tibiotic prevalence of IBS described in Table 1, there also appeared to be a lower median number of functional symp- toms in the preceding month in antibiotic-treated subjects versus controls (0.5 vs 2.0). The authors later describe results suggesting that at the time of the first questionnaire (after antibiotics) more IBS subjects had no functional symptoms. In fact, 50% of antibiotic-treated subjects re- ported no functional bowel symptoms, compared with 33% of the controls (p = 0.09). Four months after antibiotic use this trend reversed but was more statistically equal to con- trols (p = 0.2). Based on these results, the authors need at least to consider the possibility that the antibiotic use may have initially diminished functional symptoms, with return/ exacerbation of these symptoms 4 months later. There are a number of ways the authors could have sorted this out. First, they could have administered a questionnaire just before the use of antibiotics in addition to immediately after. Second, they could track the initial bowel habits (e.g., the 1st wk after antibiotics) and again compare bowel symp- toms to controls to determine if there was an initial detri- mental or beneficial effect of treatment. Third, the course of symptoms could have been tracked over time. Why was 4 months chosen? Why would there be less IBS symptoms initially upon completion of antibiotics and yet a worsening later? This needs to be discussed. There are other data supporting this alternative explana- tion whereby antibiotics may produce a beneficial effect in IBS. The first is an article by Nayak et al. (3) suggesting that metronidazole given in a double-blind placebo-controlled fashion actually improved IBS symptoms in subjects rela- tive to controls. The second is an article by our group (4) suggesting a role of intestinal flora in IBS whereby antibi- otics resulted in a significant improvement of IBS symp- toms. Although both studies are recognized to have their limitations, the authors fail to discuss this possibility and have not adequately ruled it out. Despite the criticisms, this article is important, as it again hints at the potential relationship between functional symp- toms and enteric bacteria as influenced by antibiotics. We look forward to any follow-up studies the authors have that may rule in or out any initial beneficial effects of antibiotics as a confounding factor. Mark Pimentel, M.D., F.R.C.P.C. GI Motility Program Department of Medicine CSMC Burns and Allen Research Institute Cedars-Sinai Medical Center School of Medicine University of California, Los Angeles Los Angeles, California REFERENCES 1. Maxwell PR, Rink E, Kumar D, et al. Antibiotics increase functional abdominal symptoms. Am J Gastroenterol 2002;97: 104 – 8. 2. Gwee KA, Graham JC, McKendrick MW, et al. Psychometric scores and persistance of irritable bowel after infectious diar- rhea. Lancet 1996;347:150 –3. 3. Nayak A, Karnad D, Abraham P, Mistry FP. Metronidazole relieves symptoms in irritable bowel syndrome: The confusion with so-called “chronic amebiasis.” Indian J Gastroenterol 1997;16:137–9. 4. Pimentel M, Chow EJ, Lin HC. Eradication of small intestinal bacterial overgrowth reduces symptoms of irritable bowel syn- drome. Am J Gastroenterol 2000;95:3503– 6. Reprint requests and correspondence: Mark Pimentel, M.D., F.R.C.P.C., Director, GI Motility Laboratory, Cedars-Sinai Med- ical Center, 8635 West 3rd Street, Suite 770, Los Angeles, CA 90048. Received Jan, 31, 2002; accepted Apr. 26, 2002. Enterococcus gallinarum Bacteriascites in a Patient With Active Tuberculosis and HCV Cirrhosis TO THE EDITOR: Infection of ascitic fluid includes both spontaneous bacterial peritonitis and bacteriascites. Causative microorganisms are mainly intestinal gram-negative aerobic flora. Although enterococci can be responsible for ascitic fluid infections, Enterococcus gallinarum is a rare cause of nosoco- mial infections in immunosuppressed patients. We report a case of bacteriascites caused by E. gallinarum in a patient with active tuberculosis and hepatitis C virus cirrhosis. A 67-yr-old woman with a history of hepatitis C virus cirrhosis with portal hypertension and without previous epi- 2681 AJG – October, 2002 Letters to the Editor