Triple threat: A case of Gemella morbillorum, Escherichia coli, and Granulicatella adiacens bacteremia in a patient with Crohn’s disease

Background: Gemella species is a rare gram-positive, catalase-negative, facultative anaerobic coccus, commonly found in normal gastrointestinal tract flora, oropharynx and female genital tracts. They can cause clinically significant infections, notably infective endocarditis, especially in patients with underlying risk factors. Granulicatella species are Gram-positive cocci, catalase-negative and oxidase-negative, facultatively anaerobic, found in normal oral flora. Both species behave like viridans group streptococci. Despite low incidence of bacteremia from these organisms, they can lead to infective endocarditis (IE) and other clinical syndromes including localized soft-tissue abscesses, empyema and osteomyelitis. Escherichia coli is one of the most frequent Gram- negative pathogens in sepsis and bloodstream infections. Polymicrobial bloodstream infections involving these three species are infrequent. We present a case of a patient with untreated Crohn’s disease who developed polymicrobial bacteremia and severe sepsis involving Escherichia Coli, Gemella spp and Granulicatella spp.

Case Presentation: This case concerns a forty-one-year-old female with past medical history of Crohn’s disease, severe iron deficiency anemia, and sickle cell trait who presented to the hospital with 1-week history of fevers, chills, and oliguria. She was diagnosed with Crohn’s Disease the prior year and was uncompliant with treatment. She previously received two doses of Vedolizumab infusions. However, she discontinued treatment due to severe abdominal side effects. Most recent colonoscopy performed two years prior revealed multiple inflammatory polyps, benign- appearing intrinsic non transversed severe stenosis 20cm proximal to anus. She presented with temperature 36.6 Celsius, heart rate 138 beats per minute, respiratory rate twenty-four, and blood pressure 102/67 mmHg. Physical exam notable for tachycardia and diffuse abdominal pain. Initial workup remarkable for Creatinine 6.88mg/dL, computed tomography (CT) abdomen pelvis with contrast demonstrated abnormal mural thickening of distal ileum, urinalysis positive for bacteria. Broad coverage antibiotic treatment was initiated with Cefepime and Metronidazole. Patient was admitted to hospital with diagnosis of severe sepsis with end organ renal damage. On second day of admission, 2 out of 2 blood cultures collected were positive for gram negative rods and gram-positive cocci in pairs and chains. By day 3 admission cultures identified as Granulicatella adiacens, Gemella morbillorum and Escherichia Coli. Urine culture was positive for Group B Streptococcus. Antibiotic coverage was broadened to Daptomycin. Transthoracic echocardiography (TTE) was performed day 4 admission and was negative for valve vegetations. Blood cultures repeated day 5 of hospitalization were negative for bacterial growth, prednisone was started for Crohn’s flare up. Patient exhibited satisfactory recovery and was discharged day 8 hospitalization.

Conclusion: The aim of this report is to bring up Gemella morbillorum and Granilucatella adiancens as emerging pathogens involved in sepsis and bacteremia. Both of these species can cause severe sepsis, and combination of these with Escherichia coli in single episode of sepsis is rare in the published literature. It also highlights concern for commensal bacteria as high virulent bugs in high-risk patients and need for careful identification and aggressive management, especially when source for infection is gastrointestinal translocation due to mucosal barrier disruption caused by inflammatory bowel disease.