Streptococcus anginosus pyogenic liver abscess following a screening colonoscopy

Pyogenic Liver Abscess or Liver Cyst Infection after Colonoscopic Polypectomy

A pyogenic liver abscess (PLA) mostly occurs in association with biliary tract disease, but some PLAs have no apparent underlying cause, i.e., they are cryptogenic. The authors experienced three cases of PLA or liver cyst infection after colon polypectomy without other distinct etiologies. These cases suggest that colonoscopic polypectomy can cause a mucosal defect that provides a route for bacteria to invade the portal system or spread intraperitoneally to the liver. Colonoscopic polypectomy should be considered as a procedure that might cause PLA. Moreover, clinicians should be aware of this possibility if a patient complains of fever or abdominal pain after a colonoscopic polypectomy.

Small Bowel Gastrointestinal Stromal Tumor as a Gateway for Streptococcus anginosus Causing Multiple Liver Abscesses

Gastrointestinal stromal tumors (GISTs) are the most common type of mesenchymal neoplasm of the gastrointestinal tract but consist of only 1% of all primary gastrointestinal neoplasms. Differentiated from other spindle cell tumors, GISTs are uniquely positive for CD117 expression which allows for molecular targeting therapy with imatinib mesylate (Gleevec). Clinical presentations are variable, ranging from asymptomatic to vague symptoms of abdominal pain, early satiety, abdominal distention or gastrointestinal bleeding. Very rarely, patients can present with tumor-bowel fistula and intra-abdominal abscesses. In this article, we discuss a rare presentation of a middle-aged male with multiple liver abscesses found to have a primary small bowel GIST. This patient received prompt intravenous antibiotics; however, hepatic abscesses can be easily misinterpreted as cystic hepatic metastases which can delay appropriate therapy. Streptococcus anginosus was found to be responsible for the formation of the liver abscesses visualized on computed tomography (CT) scan. Similar to Streptococcus bovis, knowledge in the literature is arising about the association between S. anginosus and gastrointestinal malignancies. This case highlights the importance of identifying concomitant primary GISTs with intra-hepatic abscesses, as these lesions can be easily misconstrued as liver metastases and consequently mismanaged. We herein emphasize that hepatic abscesses are a potential sequela of GISTs and should thus prompt further investigation for potential malignancies, if warranted, so that there is no delay in treatment of these gastrointestinal tumors.

Pyogenic Liver Abscess with No Predisposing Risk Factors

Pyogenic liver abscesses (PLA) are an uncommon cause of hospitalization in the United States. The majority of such cases are polymicrobial and are most commonly caused by seeding of infection from the biliary system. PLA is frequently associated with specific comorbidities such as diabetes mellitus, history of liver transplant, underlying hepatobiliary, or pancreatic disease. Herein, we describe a 47-year-old healthy male with no known risk factors associated with PLA who presented to the hospital with acute fever, abdominal pain, and dark colored urine. Initially the patient had a negative right upper quadrant ultrasound. However, the patient continued to have persistent fevers and abnormal liver biochemistries with negative liver serology that led to checking a magnetic resonance cholangiopancreatography which suggested multiple liver abscesses. Computer tomography guided aspiration revealed a monobacterial Streptococcus species within the abscess, which is commonly associated with arterial bacteremia as a source of PLA. Arterial bacteremia is one of most rare causes of PLA. The patient's septic workup was negative for any source of infection. This case demonstrates a patient with no risk factors who was diagnosed with PLA caused by apparent arterial bacteremia with no clear source of infection.

Liver Abscess due to Streptococcus constellatus in an Immunocompetent Adult: A Less Known Entity

BACKGROUND

Pyogenic liver abscesses (PLAs) are an uncommon, but potentially life threatening infection. We report a case of PLA due to Streptococcus constellatus, a member of the Streptococcus anginosus group (SAG) bacteria, commonly found as commensals of the oropharyngeal, gastrointestinal and genitourinary flora.

CASE

The patient, a 42-year-old man with no premorbidities, non-smoker and non-alcoholic, presented to our hospital with high-grade fever associated with chills and rigors and right upper quadrant pain of one month duration. Culture of the ultrasound-guided liver aspirate yielded a pure growth of S. constellatus subspecies constellatus identified by conventional biochemical tests. In a standard antimicrobial disk-diffusion test, the isolate was susceptible to cefepime, cefotaxime, ceftriaxone, vancomcyin, levofloxacin, clindamycin and linezolid. Treatment with parenteral ceftriaxone alongwith appropriate surgical management led to resolution of the abscess with no recurrence of infection at three months follow-up.

CONCLUSIONS

The pathogenic potential of SAG has generally been disregarded because of the commensal nature of these microorganisms; however, streptococci belonging to this group have been increasingly reported as relevant pathogens in abscesses and blood cultures. An underlying condition, such as diabetes, cirrhosis or cancer or some medical manipulation, such as dental extraction, acupuncture, or hemorrhoidectomy is associated with the majority of patients with SAG abscess. However, the present case highlights the need to include S. constellatus and other members of the SAG while investigating for etiology of PLA, even in immunocompetent adults.

Liver Cyst Infection after Colon Endoscopic Mucosal Resection in a Patient with Autosomal Dominant Polycystic Kidney Disease on Maintenance Hemodialysis

A 60-year-old Japanese man with autosomal dominant polycystic kidney disease (ADPKD) on maintenance hemodialysis underwent colonoscopy and endoscopic mucosal resection (EMR). He was hospitalized after 4 days of fever that began the day following colonoscopy. We detected Klebsiella pneumoniae in a blood culture and a ring-shaped integration in the liver cyst by gallium scintigraphy. He recovered with antibiotics and percutaneous drainage. The patient was believed to have contracted the liver cyst infection via an injured colonic mucosa and portal vein. Thus, if a patient exhibits fever after a colon EMR, for patients with ADPKD, then a liver cyst infection should also be considered in the differential diagnosis.

Ileal GIST presenting with bacteremia and liver abscess: A case report and review of literature

INTRODUCTION

Small intestine gastrointestinal stromal tumors can infrequently present with intra-abdominal abscess, perforation, obstruction or fistula. Tumor-small intestine fistula is a rare phenomenon and occurs as a result of GISTs' propensity to cause mucosal ulceration. This allows bacteria from the gut to gain access to the systemic circulation and predisposes the patient to bacteremia and pyogenic liver abscess.

PRESENTATION OF CASE

We present a case of a 63-year-old female whose initial symptoms included fever, nausea, vomiting and right upper quadrant pain. Radiologic studies revealed a liver lesion and an intra-abdominal mass containing oral contrast, suggesting involvement of the gastrointestinal tract. She was found to have a liver abscess, Streptococcus anginosus bacteremia and an ileal GIST that formed a fistula between the tumor and small intestine. We performed a surgical resection of the tumor and percutaneous drainage of the liver abscess. Imatinib was initiated post operatively and she experienced no recurrence, as demonstrated by a surveillance computed tomography scan at 12 months.

CONCLUSION

Findings of a liver lesion in association with a small intestine GIST should raise concern for both metastatic disease and a possible infectious complication such as a pyogenic liver abscess. If a member of the Streptococcus milleri group is isolated in blood cultures, a consideration for gastrointestinal malignancy is imperative. This case report reviews a rare presentation of an ileal GIST with tumor-intestinal fistula, complicated by liver abscess and Streptococcus anginosus bacteremia.

The Development of a Liver Abscess after Screening Colonoscopy: A Calculated Risk?

We present the case of a patient who developed a liver abscess following screening colonoscopy. A colorectal screening program was introduced in the Netherlands in 2014 in order to reduce mortality from colorectal cancer. The patient in this report, a 63-year-old man with no significant medical history, underwent polypectomy of two polyps. Four days afterwards he presented to our emergency department with fever, nausea and vomiting. He was diagnosed with a Klebsiella pneumoniae liver abscess and was successfully treated with antibiotics for 6 weeks. This case highlights one of the risks of screening colonoscopy. Given the high number of colonoscopies due to the colorectal screening programs, we should be aware of complications in this mostly asymptomatic group of patients.