News

A 72 year-old-patient presented to the ER with a productive cough for three days, left flank pain, and intermittent nausea.

Discussion

This case highlights the benefits of using the high negative predictive value (NPV) of the T2Bacteria Panel for early de-escalation of therapy, mainly when using antimicrobial agents that can commonly cause acute kidney injury.

Presentation

A 72 year-old-patient presented to the ER with a productive cough for three days, left flank pain, and intermittent nausea.  Pertinent laboratory values included a temperature of 38.5 ^oC, WBC of 18.5, and a lactic acid of 5.4. The patient was hospitalized one month prior for nephrolithiasis with left ureteropelvic junction (UPJ) obstruction, complicated by ESBL E. coli bacteremia, and had a left ureteral stent placed at the time. A urinalysis, urine culture, blood culture, and T2Bacteria sample were drawn in the ER, and the patient was started on meropenem and vancomycin due to recent surgery and history of ESBL E.coli infection. The patient was transferred to the ICU.

Patient Selection Criteria

Septic patient with a fever presenting to the ED

Evaluation and Treatment Decision

Empiric Therapy

The patient was started on meropenem and vancomycin

T2Bacteria Panel Result

Positive for E.coli, negative for S. aureus, P. aeruginosa, K. pneumoniae, E. faecium

Blood culture Result

Positive for E.coli (ESBL positive)

Urine culture Result

Positive for E.coli (ESBL positive)

Hospital course and decision making based on the T2Bacteria Result

The positive T2Bacteria result for E. coli came back once the patient was transferred to the ICU. The team discontinued vancomycin based on the negative T2Bacteria result for S. aureus and continued the meropenem.  The high NPV (99.7%) of the T2Bacteria Panel provided crucial diagnostic information that allowed for more informed treatment decisions, specifically the de-escalation of the anti-staphylococcal agent.  Blood and urine cultures resulted on the third day of therapy, both positive for ESBL E. coli, sensitive to meropenem.  The patient was continued on meropenem and discharged to subacute rehab with a plan to continue meropenem until their scheduled ureteral stent removal and replacement.

A severely dehydrated elderly patient was admitted for septic shock overnight.

Discussion

This case highlights not only T2Bacteria’s ability to rapidly identify specific bacterial pathogens in whole blood but also the capability to detect the causative organism in the presence of antibiotics where blood cultures remained negative, as well as an opportunity to use the result to de-escalate therapy.

Presentation

A severely dehydrated elderly patient was admitted for septic shock overnight. They presented with a fever of 102.3, WBC of 19.9, and a lactic acid of 6.5.  Upon presentation in the Emergency Room, blood cultures were taken, and they were started on broad-spectrum, empiric antimicrobials, and transferred to the ICU.  Urine cultures were taken in the morning because the suspected source of infection was genitourinary, and a T2Bacteria was run in addition to the second set of blood cultures.

Patient Selection Criteria

A septic patient presenting in the Emergency Department

Evaluation and Treatment Decision

The patient was started on piperacillin/tazobactam and levofloxacin

T2Bacteria Panel Result

Positive for E.coli

Blood Culture

Both sets of blood cultures- No growth

Urine Culture

No growth

Urinalysis

Indicative of a urinary infection

Decision making based on the T2Bacteria Result

Overnight blood cultures were obtained for an infectious workup at the time of admission, and in the early morning, a T2Bacteria was taken with the second set of blood cultures.

Despite the pending blood cultures at the time of the positive T2 result, the patient was de-escalated to a narrower spectrum antimicrobial, ceftriaxone, within 24 hours of the patient being admitted. The patient improved and was changed to oral therapy on day 5 of therapy and later discharged.

The patient presented to the emergency department 5 days after appendectomy

Discussion

This case highlights the benefit of the T2Bacteria Panel’s rapid bacterial species identification in a scenario where a patient has already received several days of empiric therapy without significant clinical improvement. Once the causative organism was identified and effective therapy was initiated, the patient experienced rapid clinical improvement. This improvement enabled the patient to be discharged 2 days after the T2Bacteria result, potentially resulting in a reduced length of stay.

Presentation

A 33-year-old patient presented to the emergency department 5 days after appendectomy. The surgery and post-operative course progressed normally until Day 4, when the patient experienced new symptoms, including abdominal pain, fever, and nausea. At the time of assessment in the emergency department, the patient reported sharp pain on the ride side along with moderate areas of redness surrounding the incisions. The patient was admitted and started on ceftriaxone and metronidazole. Blood cultures were obtained and remained negative. On Day 3, the patient had not improved significantly. T2Bacteria was ordered as well as a CT-guided drainage of a right lower quadrant collection.

Patient Selection Criteria

Patient with intra-abdominal infection not improving on empiric antibiotic therapy

Evaluation and Treatment

Diagnosis

Intra-abdominal infection following an appendectomy

Empiric Therapy

Ceftriaxone and metronidazole

Blood Culture Result

Negative

T2Bacteria Panel Result

P. aeruginosa

Culture of Fluid Collection

P. aeruginosa and clostridium species

Decision Making Based on the T2Bacteria Result

Neither Ceftriaxone nor metronidazole provides coverage for P. aeruginosa, both were discontinued. Piperacillin/tazobactam was initiated to treat P. aeruginosa, as well as to provide anaerobic coverage, including against clostridium species.  The patient showed significant improvement on Day 4 and was released from the hospital on Day 5 with oral antibiotic therapy.

An 86 year old patient was transferred to the treating hospital with signs of septic shock.

Discussion

This case highlights the benefit of T2Bacteria’s rapid bacterial species identification, which allowed for a rapid escalation of antibiotic therapy and discontinuation of unnecessary antibiotics once Pseudomonas aeruginosa was identified.

Presentation

An 86 year old patient was transferred to the treating hospital with signs of septic shock. The patient had a history of multiple hospitalizations over the last three months, with several courses of antibiotics to treat pneumonia, as well as wound and urinary tract infections. On admission, the patient was on ampicillin/sulbactam and tedizolid for the treatment of a recent wound infected with K. pneumonia and E. faecalis.

On admission, the left leg wound appeared acutely infected and the patient had a fever as well as low blood pressure requiring vasopressor support. Additionally, the patient had a low platelet count, potentially caused by tedizolid therapy.

Patient Selection Criteria

New-onset suspected sepsis and elevated SOFA score in a patient with risk factors for infection.

Evaluation and Treatment

Diagnosis

Suspected sepsis

Empiric Therapy

Ampicillin/sulbactam and tedizolid

Blood Culture Result

Negative

T2Bacteria Panel Result

P. aeruginosa

Decision Making Based on the T2Bacteria Result:

Ampicillin/sulbactam and tedizolid do not provide coverage for P. aeruginosa and both were discontinued. Ceftolozane/tazobactam was initiated for the treatment of P. aeruginosa based on the local antibiogram. The patient showed significant improvement on Day 2 and was released from the hospital after receiving aggressive wound care and completing antibiotic therapy.

86-year-old patient with a past medical history of ischemic stroke, anemia, diabetes, and hypertension was transferred to the Intensive Care Unit.

Discussion

Therapy was escalated to appropriately cover the P. aeruginosa infection in a geographic region endemic for multi-drug resistant P. aeruginosa that was not identified via the blood culture. The patient recovered from the infection and was discharged to a rehabilitation facility.

Presentation

An 86-year-old patient with a past medical history of ischemic stroke, anemia, diabetes, and hypertension was transferred to the Intensive Care Unit due to shock, respiratory distress, fever, and increased WBC. The patient was recovering from a recent hospitalization for a sacral decubitus ulcer and UTI.

Previous Cultures:

Wound Swab: K. pneumoniae and E. faecium

Urine culture from catheter: E. faecalis

Rectal swab: K. pneumoniae

The patient was admitted to the ICU with orders for new blood cultures, urine cultures, T2Bacteria Panel, and was started on empiric antibiotics, IV fluids, and vasopressors.

Patient Selection Criteria

A patient suspected of sepsis with other microbiological evidence of infection

Evaluation and Treatment Decision

Diagnosis

Septic Shock (unknown origin of infection)

Empiric Therapy

Ampicillin/sulbactam and tedizolid

T2Bacteria Result

Positive for P. aeruginosa

Blood Culture Result

no growth

Decision making based on T2Bacteria Result

A rapid T2Bacteria result allowed for the identification of the P. aeruginosa bacteremia in a patient with septic shock and blood culture-negative infection. This result prompted the prescriber to escalate therapy to ceftolozane/tazobactam and amikacin.

54-year-old male, with a past medical history of Hepatitis C, presented to the emergency department.

Discussion

This case highlights the benefit of the T2Bacteria Panel’s rapid bacterial species identification. Using T2Bacteria allowed for early identification of S. aureus endocarditis in a patient with a limited medical history that had been transferred from an outside hospital. Based on the T2Bacteria results, unnecessary antibiotics were discontinued on Day 1, and the patient received cardiology and infectious disease consultations for the management of endocarditis. The patient’s follow-on blood cultures were negative, likely due to the presence of antibiotics, but the S. aureus bacteremia was confirmed from a blood culture draw obtained prior to admission.

Presentation

A 54-year-old male, with a past medical history of Hepatitis C, presented to the emergency department as a transfer from an outlying hospital. He had septic shock and was directly admitted to the ICU for management.

Evaluation and Treatment Decision

Antibiotics on admission

oxacillin, cefepime, and daptomycin.

Vitals

Temp- 39C, HR- 100BPM

Available labs

WBC- 11.1K CRP- 11.6 mg/dl, PCT – 0.8ng/mL, lactate 1.9 mmol/L

Blood cultures and T2Bacteria were both obtained at admission after initial antibiotic administration

Positive for S. aureus and negative for all other bacterial targets. (T2Bacteria result available at 3h 30min)

Transesophageal echocardiography

Positive for endocarditis

Follow-on Blood Culture Results

no growth

Decision making based on T2Candida Result

The patient’s therapy was adjusted based on the T2Bacteria result. An echocardiogram was ordered, resulting in positive for endocarditis. Oxacillin and cefepime were discontinued, and daptomycin was continued. Blood culture results from the outside hospital were also positive for S. aureus (results received on Day 2).

52-year-old male, currently undergoing hemodialysis three times weekly with a complicated medical history.

Discussion

This case highlights the benefit of the T2Bacteria Panel’s rapid species identification, allowing for the rapid initiation of appropriate antimicrobial therapy and resulting in clinical improvement.

Presentation

The patient was a 52-year-old male, currently undergoing hemodialysis three times weekly with a complicated medical history, including diabetes, hypertension, lung cancer, chronic kidney disease. While at dialysis, he experienced confusion and hypotension. The physician was notified, and the patient was transferred to the emergency department. In the emergency department, he was believed to be dehydrated secondary to too much fluid removed during dialysis. He received fluid resuscitation, and blood cultures, and T2Bacteria were obtained. Empiric antibiotics were not initiated.

Evaluation and Treatment Decision

Vitals

Temp- 37.5, HR- 89BPM, BP- 90/60

T2 Result

Positive for E.coli.  Negative for all other bacterial targets. (results available at 6 hours after initial presentation)

Blood Culture Result

no growth reported

Decision making based on T2Candida Result

The patient’s therapy was adjusted based on the T2Bacteria result. The patient did not improve after fluid resuscitation and was being transferred to the ICU at the time of T2Bacteria result due to persistent hypotension. Orders were initially written for vancomycin and cefepime, but the T2Bacteria results were received prior to administration, and therapy was changed to ceftriaxone (targeted therapy for E.coli infection).

A 55-year-old male presented to the hospital from an outside facility with sepsis secondary to pyelonephritis.

Discussion

This case highlights not only T2Bacteria’s ability of rapid identification but also the capability to detect the causative organism in the presence of antibiotics. The patient, in this case, received a dose of ceftriaxone and azithromycin before the blood cultures and T2Bacteria were drawn. Bloodstream infection was missed by blood culture but was identified with rapid detection provided by the T2Bacteria Panel. The use of T2Bacteria, in this case, allowed an early confirmation of effective antibiotic therapy.

Presentation

A 55-year-old male presented to the hospital from an outside facility with sepsis secondary to pyelonephritis. Before transfer, the patient received one dose of ceftriaxone and azithromycin. He was subsequently admitted to ICU with septic shock and acute renal failure, which required the initiation of continuous renal replacement therapy. Blood cultures, urine cultures, and T2Bacteria sepsis panel were obtained.

Patient Selection Criteria

Critically ill patients with sepsis/septic shock and/or elevated procalcitonin

Evaluation and Treatment Decision

Diagnosis

Septic shock secondary to pyelonephritis

T2Bacteria Result

Positive for E. coli

Blood Culture Result

No growth

Urine Culture Result

E. Coli

Empiric Therapy

Cefepime

Decision making based on T2Bacteria Result

A rapid T2Bacteria result allowed for early diagnosis of E. coli bacteremia and the confirmation of effective empiric antibiotic therapy. T2Bacteria detected E. coli directly from whole blood approximately 4 hours after the patient presented to the hospital. The positive T2Bacteria result was obtained hours before the blood cultures were even able to be sent to an off-site core lab to be processed, which ultimately did not grow.

An 81-year-old patient with a complicated medical history was admitted to the hospital for a tracheoesophageal fistula repair.

Discussion

This case highlights the benefit of the T2Bacteria Panel’s turnaround time for species identification. Tigecycline has been associated with high rates of gastrointestinal adverse events such as nausea and vomiting and does not provide adequate coverage of P. aeruginosa. The rapid result provided by T2Bacteria allowed for discontinuation of Tigecycline after only one dose. Additionally, amikacin was added as an antimicrobial known to be effective against P. aeruginosa based on the institution’s antibiogram.

Presentation

An 81-year-old patient with a complicated medical history including diabetes, dysphagia, Parkinson’s Disease, and a history of multiple hospitalizations over the last six months was admitted to the hospital for a tracheoesophageal fistula repair. The patient developed signs and symptoms of pneumonia several days post-operatively. T2Bacteria, blood, sputum, and tracheostomy cultures were obtained after the patient was started on ceftolozane/tazobactam and tigecycline empirically.

Evaluation and Treatment Decision

Vitals

Temp- 36.5, HR- 69BPM

Available labs

WBC- 21.7K CRP- 22.2 mg/dl, PCT – 2.48ng/mL.

T2Bacteria Result

Positive for P. aeruginosa and negative for all other bacterial targets (results available at 5h2min)

Blood Culture Result

no growth reported

Other cultures

Tracheostomy Exit Site: P. aeruginosa, C. albicans; Rectal swab: E. faecium, P. aeruginosa

Decision Making Based on T2Bacteria Results

The patient’s therapy was adjusted based on the T2Bacteria Panel result. Tigecycline was discontinued and the patient was started on amikacin in addition to ceftolozane/tazobactam in order to provide effective coverage for P. aeruginosa.

The patient presented to the emergency department with flu-like symptoms

Discussion

This case highlights the ability of the T2Bacteria^® Panel to provide rapid species identification of causative pathogens in sepsis cases. It examines clinical challenges with current methods, including delayed blood culture growth, as well as polymicrobial infections. A rapid T2Bacteria result could have allowed for more informed treatment decisions, including earlier initiation of antibiotic therapy and earlier admission to the hospital.

Presentation

The patient presented to the emergency department with flu-like symptoms, but at the time, clinical status and workup did not warrant admission. The patient continued to decline and re-presented to the emergency department approximately 18 hours later with shortness of breath. While in the emergency department during the second visit, the blood cultures that were obtained during the earlier visit resulted positive with gram-negative rods, and the prescriber was notified. The patient was subsequently admitted, and empiric antibiotics were initiated.

Patient Selection Criteria

Procalcitonin 10.21

Evaluation and Treatment Decision

Diagnosis

bacteremia

T2Bacteria Result

(sample obtained during initial ED visit): Positive for Pseudomonas aeruginosa and E. coli

Blood culture #1 Result

(obtained during initial ED visit): Pseudomonas aeruginosa and Serratia marcescens
(time to culture positivity: 20.5 hours; time to species ID: ~2.5 days for P. aeruginosa and ~5 days for S. marcescens).

*Note: Verigene assay was performed after detection of the growth of gram-negative rod on the culture. It was positive for the detection of Klebsiella oxytoca only and not the pathogens that grew in blood culture.

Blood culture #2 Result

(obtained during second ED visit): E. coli
(time to culture positivity: 24 hours; time to species ID: ~1.5 days)

Empiric Therapy

meropenem

Decision making based on T2Bacteria Result

Note: T2Bacteria results were not reported as this case was part of an observational study.

The blood cultures that were obtained from the patient upon initial presentation had delayed the growth of gram-negative rods, which were found 22 hours later. The patient was discharged from the emergency department prior to blood culture resulting in positive for growth. The patient continued to decline and re-presented to the emergency room, requiring subsequent admission to the hospital.

Had the T2Bacteria test been performed, and the result been reported immediately after collection, the patient could have potentially avoided the premature discharge from the emergency department and earlier initiation of effective antibiotic therapy.

The patient was admitted to the hospital with COPD exacerbation and respiratory distress.

Discussion

This case highlights how the T2Bacteria Panel can guide treatment by rapidly identifying the causative pathogen in sepsis cases that are missed by blood cultures. Rapid detection of bloodstream infection by T2Bacteria could have allowed for the escalation of effective antibiotic therapy, potentially leading to the prevention of further clinical deterioration.

Presentation

The patient was admitted to the hospital with COPD exacerbation and respiratory distress. They were subsequently transferred to the ICU with respiratory failure requiring intubation and renal failure. Antibiotics were initiated at the time of admission, but no cultures were obtained. The patient continued to have fever and leukocytosis and on day 5 of hospitalization, blood cultures and T2Bacteria Panel were obtained.

Patient Selection Criteria

Patients with sepsis presenting to ICU from the Emergency Department

Evaluation and Treatment Decision

Diagnosis

fever of unknown origin, possible bloodstream infection

T2Bacteria Result

Positive for P. aeruginosa

Blood culture Result

no growth

Empiric Therapy

Ceftriaxone

Decision making based on T2Bacteria Result

T2Bacteria and blood cultures were obtained after 5 days of antibiotic therapy for an infectious workup for persistent leukocytosis and fever of unknown origin. Because this case was part of an observational study, T2Bacteria results were not reported.  Had T2Bacteria been performed and results reported immediately after collection, it may have prompted the physician to add targeted therapy and avoid clinical deterioration.

The patient presented to the Emergency Department with acute respiratory failure and was admitted to the ICU with orders for blood cultures, T2Bacteria, and empiric antibiotics.

Discussion

In this case, rapid detection of bloodstream infection by the T2Bacteria Panel could have allowed for more informed treatment decisions, including the continuation of effective antibiotic therapy, which may have led to the prevention of clinical deterioration.

Presentation

The patient presented to the Emergency Department with acute respiratory failure and was admitted to the ICU with orders for blood cultures, T2Bacteria, and empiric antibiotics.

Patient Selection Criteria

Patients with sepsis presenting to ICU from the Emergency Department

Evaluation and Treatment Decision

Diagnosis

Possible pneumonia

T2Bacteria Result

Positive for P. aeruginosa

Blood culture Result

No growth

Respiratory Culture #1 Result

Enterobacter (resistant to cefepime, susceptible to levofloxacin)

Respiratory Culture #2 Result

P. aeuriginosa (intermediate resistance to levofloxacin, susceptible to cefepime and imipenem)

Empiric Therapy

cefepime, vancomycin

Decision making based on T2Bacteria Result

T2Bacteria and blood cultures were obtained for an infectious workup at the time of admission (T2Bacteria results were not reported, as this case was part of an observational study).

Empiric antibiotics included cefepime and vancomycin. Antibiotic therapy was changed to levofloxacin on day 5 of hospitalization to target the Enterobacter species, which was identified in the first respiratory culture. The patient continued to decline, and a second respiratory culture was obtained on day 10 of hospitalization, which grew P. aeuriginosa with intermediate resistance to levofloxacin. Antibiotics were then escalated to meropenem to treat both respiratory pathogens that were isolated in cultures.

Had the institution known of the rapid T2Bacteria result of P. aeuriginosa, the physician may not have changed therapy to levofloxacin considering the patient’s risk factors and local resistance patterns. Clinical deterioration could potentially have been avoided.