Oral vancomycin hydrochloride therapy for postoperative methicillin-cephem-resistant Staphylococcus aureus enteritis

A Case of Postoperative Methicillin-Resistant Staphylococcus aureus Enterocolitis in an 81-Year-Old Man and Review of the Literature

Patient: Male, 81-year-old

Final Diagnosis: Methicillin-resistant Staphylococcus aureus bacteremia • Methicillin-resistant Staphylococcus aureus enterocolitis

Symptoms: Diarrhea • sepsis

Medication: —

Clinical Procedure: Computed tomography • echocardiography • polymerase chain reaction • whipple procedure

Specialty: Gastroenterology and Hepatology • Infectious Diseases • Surgery

Does oral vancomycin use necessitate therapeutic drug monitoring?

PURPOSE

Oral vancomycin use has generally increased as a consequence of the need to treat and/or prevent Clostridium (Clostridiodes) difficile-associated disease (CDAD). This review examines the cumulative scientific evidence that guides therapeutic monitoring of oral vancomycin therapy.

METHODS

The existing publications were reviewed from the time of the drug's inception to July 2019. This review utilized access as available in PubMed, EMBASE, CINAHL Plus, and the Cochrane Library.

RESULTS

Case reports and small patient series have documented anecdotal-associated elevations in serum levels. Correlation of absorbed vancomycin with subsequent toxicity is difficult to determine, but serum levels approaching those obtained after parenteral administration have raised concern. Prolonged usage and total dosing over 500 mg/day among adult age ranges have been associated with accumulation. In addition, risk factors for vancomycin accumulation systemically after oral dosing include renal compromise, combined oral and other enteral therapy, severe CDAD, other intercurrent bowel inflammation, polypharmacy, and increased patient complexity/morbidity.

CONCLUSION

Until systemic toxicity from oral vancomycin absorption is better understood, individual considerations should be made for therapeutic serum monitoring during oral vancomycin treatment. Therapeutic drug monitoring is suggested for several high-risk situations in which high blood levels may be anticipated.

Suppression of gut dysbiosis reverses Western diet-induced vascular dysfunction

Vascular dysfunction represents a critical preclinical step in the development of cardiovascular disease. We examined the role of the gut microbiota in the development of obesity-related vascular dysfunction. Male C57BL/6J mice were fed either a standard diet (SD) ( n = 12) or Western diet (WD) ( n = 24) for 5 mo, after which time WD mice were randomized to receive either unsupplemented drinking water or water containing a broad-spectrum antibiotic cocktail (WD + Abx) ( n = 12/group) for 2 mo. Seven months of WD caused gut dysbiosis, increased arterial stiffness (SD 412.0 ± 6.0 vs. WD 458.3 ± 9.0 cm/s, P < 0.05) and endothelial dysfunction (28% decrease in max dilation, P < 0.05), and reduced l-NAME-inhibited dilation. Vascular dysfunction was accompanied by significant increases in circulating LPS-binding protein (LBP) (SD 5.26 ± 0.23 vs. WD 11 ± 0.86 µg/ml, P < 0.05) and interleukin-6 (IL-6) (SD 3.27 ± 0.25 vs. WD 7.09 ± 1.07 pg/ml, P < 0.05); aortic expression of phosphorylated nuclear factor-κB (p-NF-κB) ( P < 0.05); and perivascular adipose expression of NADPH oxidase subunit p67phox ( P < 0.05). Impairments in vascular function correlated with reductions in Bifidobacterium spp. Antibiotic treatment successfully abrogated the gut microbiota and reversed WD-induced arterial stiffness and endothelial dysfunction. These improvements were accompanied by significant reductions in LBP, IL-6, p-NF-κB, and advanced glycation end products (AGEs), and were independent from changes in body weight and glucose tolerance. These results indicate that gut dysbiosis contributes to the development of WD-induced vascular dysfunction, and identify the gut microbiota as a novel therapeutic target for obesity-related vascular abnormalities.

Reduction in hepatic secondary bile acids caused by short-term antibiotic-induced dysbiosis decreases mouse serum glucose and triglyceride levels

Antibiotic-caused changes in intestinal flora (dysbiosis) can have various effects on the host. Secondary bile acids produced by intestinal bacteria are ligands for specific nuclear receptors, which regulate glucose, lipid, and drug metabolism in the liver. The present study aimed to clarify the effect of changes in secondary bile acids caused by antibiotic-induced dysbiosis on the host physiology, especially glucose, lipid, and drug metabolism. After oral administration of non-absorbable antibiotics for 5 days, decreased amounts of secondary bile acid-producing bacteria in faeces and a reduction in secondary bile acid [lithocholic acid (LCA) and deoxycholic acid (DCA)] levels in the liver were observed. Serum glucose and triglyceride levels were also decreased, and these decreases were reversed by LCA and DCA supplementation. Quantitative proteomics demonstrated that the expression levels of proteins involved in glycogen metabolism, cholesterol, bile acid biosynthesis, and drug metabolism (Cyp2b10, Cyp3a25, and Cyp51a1) were altered in the liver in dysbiosis, and these changes were reversed by LCA and DCA supplementation. These results suggested that secondary bile acid-producing bacteria contribute to the homeostasis of glucose and triglyceride levels and drug metabolism in the host, and have potential as therapeutic targets for treating metabolic disease.

Colonic Perforation Caused by Methicillin-Resistant Staphylococcus aureus Enteritis After Total Gastrectomy: A Case Report

A 68-year-old man underwent total gastrectomy and splenectomy for adenocarcinoma and low anterior resection for carcinoma in tubulo-villous adenoma of the rectum. Broad-spectrum antibiotics were administered for postoperative pancreatic fistula. Methicillin-resistant Staphylococcus aureus enteritis occurred on the 50th postoperative day and cecal perforation followed. The patient underwent construction of cecostomy with peritoneal drainage, and vancomycin was administered orally and per cecostomy for 2 weeks. The patient recovered well and was discharged at 35 days after re-operation in good general condition.

A systematic review for pursuing the presence of antibiotic associated enterocolitis caused by methicillin resistant Staphylococcus aureus

BACKGROUND

Although it has received a degree of notoriety as a cause for antibiotic-associated enterocolitis (AAE), the role of methicillin resistant Staphylococcus aureus (MRSA) in the pathogenesis of this disease remains enigmatic despite a multitude of efforts, and previous studies have failed to conclude whether MRSA can cause AAE. Numerous cases of AAE caused by MRSA have been reported from Japan; however, due to the fact that these reports were written in the Japanese language and a good portion lacked scientific rigor, many of these reports went unnoticed.

METHODS

We conducted a systematic review of pertinent literatures to verify the existence of AAE caused by MRSA. We modified and applied methods in common use today and used a total of 9 criteria to prove the existence of AAE caused by Klebsiella oxytoca. MEDLINE/Pubmed, Excerpta Medica Database (EMBASE), the Cochrane Database of Systematic Reviews, and the Japan Medical Abstract Society database were searched for studies published prior to March 2013.

RESULTS

A total of 1,999 articles were retrieved for evaluation. Forty-five case reports/series and 9 basic studies were reviewed in detail. We successfully identified articles reporting AAE with pathological and microscopic findings supporting MRSA as the etiological agent. We also found comparative studies involving the use of healthy subjects, and studies detecting probable toxins. In addition, we found animal models in which enteritis was induced by introducing MRSA from patients. Although we were unable to identify a single study that encompasses all of the defined criteria, we were able to fulfill all 9 elements of the criteria by collectively analyzing multiple studies.

CONCLUSIONS

AAE caused by MRSA-although likely to be rarer than previous Japanese literatures have suggested-most likely does exist.

Enteral vancomycin and probiotic use for methicillin-resistant Staphylococcus aureus antibiotic-associated diarrhoea

A geriatric patient status post intraabdominal surgery presented with persistent diarrhoea and heavy intestinal methicillin-resistant Staphylococcus aureus (MRSA) growth after multiple courses of antibiotic therapy. Additionally, swab cultures of the anterior nares tested positive for MRSA. In order to impede infection and prevent future complications, the patient received a 10-day course of vancomycin oral solution 250 mg every 6 h, 15-day course of Saccharomyces boulardii 250 mg orally twice daily and a 5-day course of topical mupirocin 2% twice daily intranasally. Diarrhoea ceased during therapy and repeat cultures 11 days after initiating therapy demonstrated negative MRSA growth from the stool and nares. Further repeat cultures 5 months later revealed negative MRSA growth in the stools and minimal MRSA growth in the nares. Overall, enteral vancomycin and probiotics successfully eradicated MRSA infection without intestinal recurrence. Although the results were beneficial treating MRSA diarrhoea for our patient, these agents remain highly controversial.

Changes in the agr locus affect enteritis caused by methicillin-resistant Staphylococcus aureus

We studied the characteristics of methicillin (meticillin)-resistant Staphylococcus aureus (MRSA) strains that caused enteritis. In a previous report, we demonstrated that both phenotypic and genotypic changes were associated with MRSA enteritis; and we hypothesized that the accessory gene regulator (agr), which is a global regulator of staphylococcal virulence and upregulates several exoproteins, is the key factor associated with the development of MRSA enteritis. In this study, we examined 12 MRSA isolates associated with enteritis from stool samples and 17 MRSA isolates not associated with enteritis that had the following characteristics: the strains associated with enteritis had the same genotype (genotype A), as detected by pulsed-field gel electrophoresis, or the strains were isolated from stools. The differences between strains that caused enteritis and those that did not cause enteritis strains were examined by quantitative reverse transcription-PCR to assess RNAII, agrA, RNAIII, and tst expression and by sequencing of the agr locus. The levels of expression of agrA, RNAIII, and tst were higher by the MRSA isolates associated with enteritis than by the MRSA isolates not associated with enteritis, whether or not they were of the same genotype. The levels of expression of RNAII by almost all the clinical isolates were similar. Sequencing of the agr locus showed that all MRSA isolates that caused enteritis have agr mutations, whereas the MRSA isolates that did not cause enteritis, with three exceptions, did not. Many of the isolates associated with enteritis had the same mutation, especially at the C-terminal end of agrA. These results suggest a trend in which mutations in the agr locus modify the expression of agrA and RNAIII and the production of toxin, all of which may increase the virulence and influence the occurrence of MRSA enteritis.

Frequency and possible infection control implications of gastrointestinal colonization with methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of health care-associated infections. Multiple factors, including transmission from unrecognized reservoirs of MRSA, are responsible for failure to control the spread of MRSA. We conducted prospective surveillance to determine the frequency of gastrointestinal colonization with MRSA among patients and its possible impact on nosocomial transmission of MRSA. Stool specimens submitted for Clostridium difficile toxin A/B assays were routinely inoculated on colistin-naladixic acid agar plates, and S. aureus was identified by using standard methods. Methicillin resistance was confirmed by growth on oxacillin-salt screening agar. For patients whose stool yielded MRSA, information regarding any previous cultures positive for MRSA or other organisms that would require contact precautions was obtained from the laboratory's computer system. During a 1-year period, 151 (9.8%) of 1,543 patients who had one or more stool specimens screened had MRSA in their stool. Ninety-three (62%) of the 151 patients had no previous history of MRSA colonization or infection. Of these 93, 75 were inpatients. Sixty (80%) of the 75 inpatients with no previous history of MRSA were not under "contact precautions." The 60 patients would have spent an estimated total of 267 days without being placed under contact precautions if their positive stool cultures had not resulted in their being isolated. Placing patients under contact precautions based on their positive stool cultures prevented an estimated 35 episodes of MRSA transmission. We conclude that gastrointestinal colonization with MRSA may serve as an unrecognized reservoir from which transmission of MRSA may occur in health care facilities.

Postoperative methicillin-resistant Staphylococcus aureus enteritis following hysterectomy: a case report and review of the literature

Following a hysterectomy a 43-year-old woman developed colicky abdominal pain and profuse postoperative diarrhoea. Examination was unremarkable and initial investigations revealed a normal plain abdominal X-ray initially, but later there was some small bowel dilatation and evidence of raised inflammatory markers. No cause was identified at exploratory laparotomy 2 days post operation. Flexible sigmoidoscopy was normal. The patient was empirically treated with oral vancomycin for presumed Clostridium difficile diarrhoea, although subsequent stool cultures were negative for the usual intestinal pathogens and C. difficile toxin. The diarrhoea persisted for 9 days. By day 10 stool cultures had grown methicillin-resistant Staphylococcus aureus, establishing the diagnosis. To our knowledge this is the first report of methicillin-resistant S. aureus enteritis following hysterectomy.

Molecular epidemiology of enteritis-causing methicillin-resistant Staphylococcus aureus

In the early 1990s, severe enteritis caused by methicillin-resistant Staphylococcus aureus (MRSA enteritis) was prevalent in Japan, but the incidence has since decreased. We compared the genotypes and phenotypes of 12 isolates that caused MRSA enteritis (enteritis isolates), detected between 1990 and 1993, with 186 non-enteritis isolates detected between 1998 and 2002. Organisms were investigated using pulsed-field gel electrophoresis (PFGE), coagulase typing and reverse passive latex agglutination to detect production of staphylococcal enterotoxins (SE) and toxic shock syndrome toxin-1 (TSST-1); and polymerase chain reaction (PCR) for detection of the structural genes entA, entB, entC, entD and tst, which encode proteins SE-A, SE-B, SE-C, SE-D and TSST-1, respectively. The 12 enteritis isolates were classified into four types and four subtypes. Only seven of the 186 non-enteritis isolates had PFGE patterns indistinguishable from the enteritis isolates. Eight of the 12 enteritis isolates had entA, entC and tst, and produced high levels of SE-A and TSST-1, but not SE-C. Of the 186 non-enteritis isolates, 157 produced SE-C and TSST-1, but not SE-A. The seven non-enteritis isolates with a PFGE pattern indistinguishable from the enteritis isolates did not produce SE-A, and showed relatively low levels of TSST-1 production. These isolates may have continued to inhabit our ward since the earlier outbreak, but acquired a different phenotype. In conclusion, the disappearance of MRSA enteritis may have resulted from the decreased incidence of enteritis-causing clones and phenotypical changes.

Nosocomial antibiotic-associated diarrhea associated with enterotoxin-producing strains of methicillin-resistant Staphylococcus aureus

OBJECTIVES

The aim of this study is to present new evidence that enterotoxin-producing strains of methicillin-resistant Staphylococcus aureus may cause nosocomial antibiotic-associated diarrhea.

METHODS

We conducted a prospective study that utilized standard methods to exclude other bacterial, parasitic, and viral pathogens as causes of nosocomial diarrhea in patients with heavy growth of methicillin-resistant S. aureus in their stool. Staphylococcal enterotoxin assays were performed on S. aureus strains recovered from patients' stools and on stool specimens from affected patients. Retrospective cohort studies compared the severity of diarrhea in patients with methicillin-resistant S. aureus-associated diarrhea with that of patients whose stool did not contain the organism and with patients colonized or infected with enterotoxin-negative methicillin-resistant S. aureus strains.

RESULTS

During an 18-month period, 11 patients had nosocomial antibiotic-associated diarrhea associated with enterotoxin-producing strains of methicillin-resistant S. aureus. Other common bacterial, parasitic, and viral pathogens were excluded. S. aureus strains from the 11 patients produced staphylococcal enterotoxin A, A and B, or D. Eighty-nine percent of patients had the same enterotoxin(s) in stool specimens as produced by the strain recovered from their stool. Case patients had a greater number of days of diarrhea than patients without methicillin-resistant S. aureus in their stool (p < 0.001), or randomly selected patients colonized or infected with enterotoxin-negative methicillin-resistant S. aureus (p < 0.001).

CONCLUSIONS

Our findings provide evidence that enterotoxin-producing strains of methicillin-resistant S. aureus may cause nosocomial antibiotic-associated diarrhea. Greater recognition of this disease should result in more rapid and appropriate treatment of affected patients.

Role of macrophages in a mouse model of postoperative MRSA enteritis

BACKGROUND

We have established a mouse model for fatal postoperative enteritis due to Staphylococcus aureus to analyze mechanisms of bacterial translocation and determine reasons for the lethality of this infection. In the present study the role of macrophages was ascertained in protection against S. aureus induced enteritis.

MATERIALS AND METHODS

Mice were pretreated with cyclophosphamide (CY), an immunosuppressant, and then infected directly into the jejunum with methicillin-resistant S. aureus (MRSA) isolated from a patient. In other groups of mice liposome-encapsulated dichloromethylene diphosphate (Cl2MDP) was administered to deplete macrophages in vivo. Other experimental groups received lipoteichoic acid (LTA), which was used to inhibit the ability of macrophages to bind MRSA, and additionally, to analyze dependence of bacterial clearance on the macrophage scavenger receptor. The ability of macrophages to bind MRSA was compared with survival rates in this mouse model of fatal postoperative enteritis.

RESULTS

Injection of liposome-encapsulated Cl2MDP decreased survival rate of mice infected intraintestinally with MRSA in a dose-dependent manner. Cyclophosphamide also decreased survival rate of MRSA-infected mice and was found to correlate with its ability to decrease the number of macrophages in the spleen. Intravenous LTA administration did not affect total splenocyte numbers or the number of splenic macrophages but decreased the ability of macrophages to bind MRSA and adversely affected survival of mice infected with MRSA.

CONCLUSIONS

Macrophages play a critical role in protection against MRSA administered directly into the jejunum. LTA recognition sites (probably type A scavenger receptors) on macrophages are required for binding and phagocytosing MRSA.

Decolonization of methicillin-resistant Staphylococcus aureus using oral vancomycin and topical mupirocin

The objective of this study was to assess the efficacy and safety of a short course of oral vancomycin and intranasal mupirocin ointment in the eradication of methicillin-resistant Staphylococcus aureus (MRSA) colonization. During an outbreak of MRSA, the colonized subjects received oral vancomycin and topical mupirocin. They were screened for MRSA 1, 3, 6 and 12 months after decolonization. A questionnaire was developed to evaluate the side-effects of oral vancomycin. Thirty-five subjects were treated. Clearance was achieved in all cases, in 24 (69%) subjects after one course of therapy. Twenty-eight (80%) subjects experienced some side-effects, including six (17%) who did not tolerate oral vancomycin. Although oral vancomycin, in combination with topical mupirocin, is effective in the elimination of MRSA colonization, there is a need for further studies to confirm our results and to evaluate the safety of oral vancomycin.

A mouse model for postoperative fatal enteritis due to Staphylococcus infection

BACKGROUND

Postoperative infection of intestine with methicillin-resistant Staphylococcus aureus (MRSA) is fatal in some cases. The object of this study was to establish a mouse model for the infection, providing a useful tool for investigating mechanisms in the progression of infection.

METHODS

Mice were pretreated with cyclophosphamide, injected orally or directly into jejunum with MRSA prepared from a postoperative patient, and then given 5 daily doses of antibiotics. Forty-eight hours after the injection, bacterial translocation and serum endotoxin levels were examined. Macrophage depletion was carried out by the administration of liposome-encapsulated dichloromethylene diphosphate (Cl(2)MDP), 4 days before MRSA injection.

RESULTS

Injection into the jejunum but not oral administration of MRSA induced enteritis with diarrhea and resulted in death in most cyclophosphamide-treated mice. Translocation of MRSA in mesenteric lymph nodes and liver was observed, concomitantly with E. coli infection. Endotoxin-resistant C3H/HeJ mice infected with MRSA survived longer than endotoxin-sensitive C3H/He mice, but also died within a week after MRSA injection. Selective depletion of macrophages induced infection in mice that were not pretreated with cyclophosphamide.

CONCLUSION

We established a mouse model for the fatal MRSA infection which induced enteritis with diarrhea, that will be a useful tool for investigating the mechanisms for sometimes fatal MRSA infection of the intestine in postoperative patients. The presence of E. coli or endotoxin seemed to play a major role in the mortality of mice in the early days of MRSA-induced enteritis, but other factors, probably from MRSA, in the later days. Phagocytes were quite important for protection against the MRSA infection.

New methods of control against postoperative methicillin-resistant Staphylococcus aureus infection

The incidence of postoperative infections caused by methicillin-resistant Staphylococcus aureus (MRSA) in Japan has been increasing dramatically. In March 1990, we assigned special doctors in infection control (infection control doctor, ICD), and defined comprehensive controls against MRSA infection. A total of 3536 cases of digestive tract surgery performed at our department were studied during the period between September 1987 and August 1997. We changed the use of antibiotics to prevent postoperative infection. Cefazolin (CEZ) was employed for surgery of the upper digestive tract, including esophagus, stomach, duodenum, and gallbladder. Cefotiam (CTM) was employed for surgery of the lower digestive tract, liver, and pancreas. In esophageal resection, the tracheal tube was extracted during the early postoperative period, and for cervical esophagogastroanastomosis, the autosuture was changed to layer-to-layer anastomosis. We have achieved successful control of postoperative MRSA infection, the incidence having decreased to 0.3% (9/2703). In conclusion, our methods of control against postoperative MRSA infection implies that comprehensive measures of prevention, including the reviewed specification and usage of antibiotics and operation management, have been well implemented. This value is the lowest and the first of any domestic hospital or institute in Japan, suggesting a continued and significant decrease.