Spontaneous small bowel perforation secondary to Vibrio parahaemolyticus infection: A case report

Shih-Chun Chien,Chih-Chung Chang,Shih-Chao Chien

Shih-Chun Chien,Shih-Chao Chien,Department of Emergency Medicine,Mackay Memorial Hospital,Taipei 104,Taiwan

Chih-Chung Chang,Department of Emergency Medicine,Taitung Mackay Memorial Hospital,Taitung 950,Taiwan

Abstract BACKGROUND Vibrio pararhaemolyticus (V.parahaemolyticus),a pathogen that commonly causes gastroenteritis,could potentially lead to a pandemic in Asia.Its pathogenesis and molecular mechanisms vary,and the severity of illness can be diverse,ranging from mild gastroenteritis,requiring only supportive care,to sepsis.CASE SUMMARY We outline a case of a 71-year-old female who experienced an acute onset of severe abdominal tenderness after two days of vomiting and diarrhea prior to her emergency department visit.A small bowel perforation was diagnosed using computed tomography.The ascites cultured revealed infection due to V.parahaemolyticus CONCLUSION Our case is the first reported case of V.parahaemolyticus-induced gastroenteritis resulting in small bowel perforation.

Key Words: Vibrio parahaemolyticus; Gastroenteriti; Small bowel perforation; Bacteria;Infections; Case report

INTRODUCTION

Vibrio pararhaemolyticus(V.parahaemolyticus) is a gram negative bacterium that can cause various infections,such as acute gastroenteritis and skin infection through wound contamination[1].Infection typically results from the consumption of seafood,such as shellfish,or exposure to seawater.This pathogen is commonly responsible for pandemics in Asia with increasing frequency in Western countries in warmer months[1].

Symptoms ofV.parahaemolyticus-induced gastroenteritis include abdominal cramping and pain,watery diarrhea,headache,nausea,vomiting,and low-grade fever.In the majority of cases,symptoms are usually self-limiting in immunocompetent patients who are adequately hydrated[2].Occasionally,antibiotics,such as azithromycin and ciprofloxacin,may be indicated[3].V.parahaemolyticusinfection may progress to more severe conditions such as septicemia through intestinal invasion[4]due to underlying stress or other risk factors including cancer; liver,kidney,and heart diseases,recent gastric surgery,and antacid use[5].

The spectrum of disease is diverse due to its complex virulence factors.We present a case ofV.parahaemolyticus-induced acute gastroenteritis complicated by spontaneous small bowel perforation.

CASE PRESENTATION

Chief complaints

A 71-year-old woman presented to our emergency department with complaints of acute-onset,severe abdominal cramping pain that started several hours prior to arrival.

History of present illness

Forty-eight hours prior to presentation,the patient had experienced several vomiting episodes as well as 6-7 episodes of watery diarrheaperday.

History of past illness

She had a history of hypertension controlled by medication.

Physical examination

On arrival,her vital signs were as follows: Temperature was 37.3 °C; heart rate was 83 beats/min; respiratory rate was 18 breaths/min; blood pressure was 99/64 mmHg;and pulse oximetry (SPO2) was 97%.She was fully conscious (Glasgow Coma Scale:E4V5M6).Physical examination revealed mild abdominal tenderness,and the abdomen was tympanic on percussion.

Laboratory examinations

Laboratory data revealed leukocytosis with neutrophil predominance [white blood cell count: 10600/μL (normal: 4000-10000/μL),neutrophil percentage: 88.6% (normal: 55-75%)],and pre-renal azotemia [blood urine nitrogen: 22.1 mg/dL (normal: 8-20 mg/dL) and creatinine: 0.59 mg/dL (normal: 0.4-1.2 mg/dL)].No elevated C-reactive protein levels or coagulopathy were noted.A general urine examination revealed no pyuria.Because of her peritoneal signs,we scheduled an abdominal computed tomography (CT) scan for further evaluation.

Imaging examinations

The abdominal CT scan with and without contrast medium revealed multiple,focal areas of extraluminal air in the left lower mesentery with adjacent small bowel edema,accompanied by focal congested mesentery and small ascites in the coronal section(Figure 1).

FINAL DIAGNOSIS

Based on these findings,a small bowel perforation secondary to anV.Parahaemolyticusinfection was made.

TREATMENT

For symptomatic control,we administered 30 mg of intravenous ketorolac tromethamine,20 mg of hyoscine butyl bromide,and 5 mg of prochlorperazine.For infection control,ertapenem (1 g) was given daily for 10 d.The patient was then transferred for an emergency laparotomy after consulting with a general surgeon.

The general surgeon elected to perform open surgery to better survey the abdominal cavity.A necrotic perforation was noted 80 cm from the ileocecal junction(Figure 2).A wedge resection encompassing the perforation was performed,followed by the creation of an end-to-end anastomosis.A Jackson-Pratt surgical drain was inserted.The peritoneal cavity was irrigated with warm saline.Finally,the turbid ascites were evacuated,and samples were sent for culture,which revealedV.parahaemolyticus.We maintained the patient on a 10 d antibiotic course.

OUTCOME AND FOLLOW-UP

The patient was discharged after 10 d without any discomfort.She was followed up at the outpatient department two weeks later without any complications.

DISCUSSION

Spontaneous perforation of the small intestine is a rare sequelae of infective gastroenteritis.Several pathogens are associated with such complications including viruses (Cytomegalovirus),bacteria (Salmonella typhi,Mycobacterium tuberculosis,andTropheryma whipplei),fungi (histoplasmosis,candida),parasites (roundworm),and protozoans (Entamoeba histolytica)[6,7].To the best of our knowledge,this is the first case report ofV.parahaemolyticus-induced spontaneous small bowel perforation.

V.parahaemolyticusis usually managed with supportive treatment.However,it can have varied presentations inV.parahaemolyticus-induced gastroenteritis.Akedaet al[4]noted thatV.parahaemolyticusmay have an invasive form that allows it to invade the intestinal epithelium leading to septicemia[4].In our case,the patient’s infection led to another life-threatening condition,a small bowel perforation.The range in disease severity is due to the complex pathogenesis ofV.parahaemolyticus,which can induce chemotoxicity,cytotoxicity,and enterotoxicity.To date,there are multiple pathways that induce disease mechanisms: (1) Hemolysins,including thermostable direct hemolysin (TDH),TDH-related hemolysin,and thermolabile hemolysin; (2) Secretory systems,such as the type 3 and 6 secretory systems; (3) Adhesion factors,such as hemagglutinin and enolase; (4) Iron reuptake system; (5) Lipopolysaccharide; (6)Proteases; and (7) Outer membrane proteins[8].The main virulence mechanisms related to enterotoxicity were: (1) TDH that increases calcium ion concentration in intestinal cells and opens the chloride channel to facilitate chloride secretion in intestinal cells;(2) Type 3 secretion system-2 which can target the cytoskeleton and manipulate cell signal transduction (the mitogen-activated protein kinase or nuclear factor-k-gene binding pathway) through different effectors (VopA,VopT,VopL,VopV,VopC,VopZ,and VPA1380),which can lead to diarrhea and facilitate bacterial invasion into the epithelium; and (3) Adhesion factors,such as mannose-sensitive hemagglutinin and nitrogen-limitation sigma factor (RpoN),which can facilitate colonization ofV.parahaemolyticusin the intestine[8].Additionally,strain-to-strain differences amongV.parahaemolyticusare remarkable.The O3:K6 strain that usually induces pandemics in Asia contains the tdh gene but not the trh gene.The level of TDH may vary in different isolated strains[9].Environmental factors such as temperature and acid-base status also play a role in pathogenesis[9].The exact mechanism still needs clarification.

Figure 1 The abdominal computed tomography with and without contrast revealed focal extraluminal air in the left lower mesentery with adjacent bowel edema indicative of small bowel perforation.

Figure 2 Necrotic perforation 80 cm from the ileocecal junction.

A limitation of our study is that the patient did not have a previous colonoscope survey.We cannot exclude whether there was a pre-existing congenital or acquired structure abnormality,such as Crohn's disease,lymphoma,or other underlying lesion.We also cannot exclude any underlying mesentery vascular lesions,which can,in rare cases,cause a spontaneous small bowel perforation.Additionally,we did not perform molecular studies to determine the virulence factors for this pathogenic strain ofV.parahaemolyticus.

CONCLUSION

V.parahaemolyticusis a common pathogen causing acute gastroenteritis in Asia.In addition to supportive and antibiotic treatments that are typically used,it is important to be aware of the possible complications that may require surgical intervention such as small bowel perforations.