News

A 23-year-old female with a history of acute myeloid leukemia and recent haploidentical stem cell transplant, cytokine release syndrome and severe mucositis following receipt of post-transplant cyclophosphamide therapy.

Discussion:

Upon admission, the patient was initially given cefepime for the treatment of febrile neutropenia. Due to the patient’s history of AML and neutropenia, she was at risk for organisms such as P. aeruginosa in addition to other common causes of febrile neutropenia such as Enterobacteriaceae.

At the time of admission, she had blood cultures obtained and T2Bacteria ordered. At this hospital, patient selection for T2Bacteria testing included onco-hematologic and HSCT patients with suspected bloodstream infections.

Bloodstream infections are a major cause of life-threatening complications in patients with cancer, due to the potential delays in chemotherapy, longer hospital stay, suboptimal treatment, higher mortality rate, and increased healthcare costs. The poor performance of blood cultures has a major impact on the clinical management of febrile neutropenic patients, especially in cases of unexplained persistent fever. T2Bacteria direct from blood diagnostic technology provided clinically relevant information for the diagnosis of infection in this case of blood culture-negative febrile neutropenia. Cefepime was continued for a total of 7 days, which was 2 days longer than would have been prescribed based on the negative blood cultures after the patient defervesced and ANC increased to >500.

Presentation

A 23-year-old female with a history of acute myeloid leukemia and recent haploidentical stem cell transplant, cytokine release syndrome, and severe mucositis following receipt of post-transplant cyclophosphamide therapy. The patient developed fever and blood cultures, T2Bacteria, and empiric antibiotics were ordered.

Patient Selection Criteria

Febrile neutropenia in a patient with AML

Evaluation and Treatment Decision

Diagnosis

Neutropenic fever

Empiric Therapy

Cefepime

Cefepime was chosen for coverage of common causative pathogens identified in febrile neutropenia.

T2Bacteria Result

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

Blood Culture Result

No growth

Decision making based on T2Bacteria Result

A rapid T2Bacteria result allowed for early diagnosis of P. aeruginosa bacteremia and confirmation of effective empiric antibiotic therapy. Identification of P. aeruginosa by T2 also provided important diagnostic information that allowed for more informed treatment decisions, including the continuation of IV antibiotics for longer treatment duration.

The patient had a history of multiple myeloma, prostate cancer, & CHF.

Discussion

This case highlights not only T2Bacteria’s benefit of rapid identification but also the ability to detect the causative organism in the presence of antibiotics as this patient had received the dose of vancomycin before the T2Bacteria was drawn.

Utilization of the T2Bacteria test allows for directed therapy on the same day as the identification of suspected infection. In this case, it took almost 48 hours from admission to identify S. aureus in the blood (Day 3 of admission). Ordering T2Bacteria at 24 hours after admission allowed appropriate therapy to be started on Day 2. Had T2Bacteria had been ordered simultaneously with blood culture, appropriate therapy could have been started on Day 1.

Initial Presentation

A high-risk patient was admitted with pulmonary edema and suspected pneumonia. The patient had a history of multiple myeloma, prostate cancer, and CHF. Blood cultures were obtained, and the patient was started on intravenous antibiotics for coverage of pneumonia.

Evaluation and Treatment Decision

Empiric Therapy

The patient was started on levofloxacin and piperacillin/tazobactam for empiric coverage of pneumonia.

Blood Culture Result

Twenty-four hours after admission, the nursing unit was called with a critical result from microbiology: gram-positive cocci in clusters.

Updated Therapy

The physician was notified, and a single dose of vancomycin was ordered.

T2Bacteria Result

The physician was uncertain if the organism might be a contaminating organism such as Staphylococcus epidermidis or a more concerning pathogen such as Staphylococcus aureus. The nurse suggested ordering T2Bacteria, and four hours later, the T2Bacteria resulted as S. aureus prompting the appropriate continued therapy with vancomycin. S. aureus was confirmed by the blood culture result the following morning.

Decision Making Based on T2Bacteria Result

The T2Bacteria Panel was used to detect the presence of S. aureus, allowing appropriate therapy to be initiated one day earlier than using blood culture alone.

81 year old female admitted with a one-day history of fever, rigors, weakness, and confusion. Blood and urine cultures were ordered as well as IV antibiotics.

Discussion/Decision Making Based on T2Bacteria Result

At this point in time, the hospital has not adopted T2Bacteria, however, another hospital in their system has. Given the high likelihood that the repeat BCx would be negative, they were asked to draw a blood sample on the day the patient was ready for discharge and send it to the institution that currently utilized the T2Bacteria Panel.

A courier was called and the test was run 4.5 hours after the blood was drawn, and resulted in 3.5 hours with no organisms detected.  The information was relayed to the ordering resident and physician, and the patient was subsequently discharged roughly a day earlier with oral antibiotics.  The clinician noted that even though this was not standard use of this test, it saved a patient a day in the hospital and also potentially spared the patient additional risk of hospital-acquired infections, further confusion, deconditioning, and risk of falls.

Presentation

81 year old female admitted with a one-day history of fever, rigors, weakness, and confusion. Blood and urine cultures were ordered as well as IV antibiotics.

Hospital Course

The patient was started on broad-spectrum IV antibiotics and baseline BCx and UCx grew E. coli.  The patient rapidly defervesced after the initial antibiotics and was de-escalated to IV ceftriaxone and clinically improved. The patient was ready for discharge two days later, though need to wait for repeat BCx drawn that day to show no growth for 48 hours, thus, prolonging their stay an additional two days. It was noted the patient had an identical episode nine years ago, with a very sensitive E. coli in BCx and UCx and was discharged on oral ciprofloxacin.

The T2Candida Panel was used to assess for the presence of disease and continuation of antifungal therapy, despite negative blood cultures.

Discussion

Rapid molecular diagnostics such as T2MR technology may help with the prognosis of invasive candidiasis. For our case, the T2Candida Panel was utilized upon follow-up to assess clearance of candidemia along with clinical symptoms.

Presentation

A 69-year-old man with a history of testicular cancer, chronic kidney disease, anemia, gangrenous gallbladder, status post cholecystectomy, hypertension, hyperlipidemia, type 2 diabetes mellitus, paroxysmal atrial fibrillation, heart failure with reduced ejection fraction and implantable cardioverter-defibrillator (ICD), and aortic valve disease s/p mechanical aortic valve replacement who presented with fatigue, fever, diarrhea, emesis, febrile to 102.3 degrees Fahrenheit with a blood pressure of 93/43 mm Hg, heart rate of 64 bpm, and respiratory rate of 18 breaths/min.

Evaluation and Treatment Decision

Initial Diagnosis

Initially diagnosed with Candida parapsilosis bloodstream infection and treated with liposomal amphotericin B at 5 mg/kg/day. After developing acute kidney injury, therapy was changed to micafungin 150 mg intravenous (IV) daily.

Blood Cultures and Echography

Repeat blood cultures continued to grow Candida parapsilosis 10 days after admission. A trans-esophageal echocardiogram (TEE) revealed fibrin stranding on the mechanical aortic valve. Due to his multiple comorbidities, he was not deemed safe for surgical intervention.

Updated Therapy

Micafungin 150 mg IV daily and fluconazole 400 mg orally daily

Discharge Plan

A peripherally inserted central catheter (PICC) was placed, and the patient was discharged from the hospital to complete micafungin IV for 12 weeks plus fluconazole oral combination therapy.

T2Candida Panel – Initial Result

Six weeks after negative blood cultures, a T2Candida Panel was ordered, which still detected the presence of Candida parapsilosis. However, all repeat fungal blood cultures remained negative, and the patient had improved overall.

T2Candida Panel – Second Result

18 weeks after blood cultures became negative, a repeat T2Candida Panel was negative for any Candida species while on chronic suppression with fluconazole.

One year later, the patient currently remains alive and doing well on oral fluconazole suppressive therapy at 200 mg daily.

Decision making based on T2Candida Result

The T2Candida Panel was used to assess for the presence of disease and the continuation of antifungal therapy, despite negative blood cultures.

1. Ahuja, Tania, Karen Fong, and Eddie Louie. “Combination antifungal therapy for treatment of Candida parapsilosis prosthetic valve endocarditis and utility of T2Candida Panel®: A case series.” IDCases 15 (2019): e00525.

83-year-old male presented to the emergency department with urinary retention.

Had the T2Bacteria test been performed and the result been reported immediately after collection, the patient could have been initiated on effective empiric therapy over 24 hours sooner, and P. aeruginosa bacteremia identified over two days earlier.

Discussion

Upon admission, the patient was initially given ceftriaxone for the treatment of suspected urinary tract infection.  At the time of admission, he had blood and urine cultures obtained, and T2Bacteria ordered. At this institution patient selection for T2Bacteria testing was based on elevated lactate and/or procalcitonin in patients presenting to the emergency department with suspected bloodstream infections.

Empiric therapy was chosen to cover E.coli, the most common cause of urinary tract infection. This patient did not present with usual risk factors for P. aeruginosa; thus effective therapy against P. aeruginosa was not initiated until urine cultures demonstrated the growth of P. aeruginosa over 24 hours after admission (T2Bacteria results were not reported as this case was part of an observational study). Blood culture growth with P. aeruginosa was delayed >48 hours after admission.

Presentation

83-year-old male presented to the emergency department with urinary retention. Sepsis was suspected, and the patient was admitted with orders for blood and urine cultures, T2Bacteria, and antibiotics.

Patient Selection Criteria

Lactic acid 3.29

Evaluation and Treatment Decision

Diagnosis

Urinary tract infection

Empiric Therapy

Ceftriaxone

Ceftriaxone was chosen for coverage of common causative gram-negative pathogens of UTIs.

T2Bacteria Panel Result

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

Blood Culture Result

P. aeruginosa (>48 hours after admission)

Urine Culture Result

P. aeruginosa (24 hours after admission)

Decision making based on T2Bacteria Panel Result:

A rapid T2Bacteria result could have allowed for more informed treatment decisions, including the initiation of earlier effective therapy.

A rapid T2Bacteria result could have allowed for more informed treatment decisions, including the initiation of earlier effective therapy over 30 hours sooner.

Discussion

Upon admission, the patient was initially given ceftriaxone and azithromycin for the treatment of suspected community-acquired pneumonia. Due to the patient’s history of COPD, he was at risk for organisms such as MRSA (methicillin-resistant Staphylococcus aureus) in addition to the more common causes of community-acquired pneumonia such as Streptococcus pneumoniae and atypical organisms.

At the time of admission, he had blood cultures obtained, and T2Bacteria ordered. At this hospital, patient selection for T2Bacteria testing was based on elevated lactate and/or procalcitonin in patients presenting to the emergency department with suspected bloodstream infections.

Effective therapy against MRSA was not initiated until blood cultures demonstrated the growth of S. aureus over 30 hours after admission (T2Bacteria results were not reported as this case was part of an observational study). Had the T2Bacteria test been performed and result been reported immediately after collection, the patient could have been initiated on effective empiric therapy over 30 hours sooner.

Presentation

A 59-year-old male with a history of rectal cancer and COPD. The patient presented to the emergency department with shortness of breath, cough, fever, and chills. Sepsis was suspected, and the patient was admitted with orders for blood cultures, T2Bacteria, and antibiotics.

Patient Selection Criteria

Lactic acid 2.8 mg/dl

Procalcitonin 59 ng/ml

Evaluation and Treatment Decision

Diagnosis: Community-acquired pneumonia

Empiric Therapy: Ceftriaxone, Azithromycin

Ceftriaxone and azithromycin were chosen for coverage of common causative respiratory pathogens identified in community-acquired pneumonia.

T2Bacteria Result: Positive for S. aureus and negative E. faecium, P. aeruginosa, E. coli, and K. pneumoniae.

Blood Culture Result: Methicillin-resistant Staphylococcus aureus (36-hour delay in species identification from time of blood culture collection)

Decision making based on T2Bacteria Result

A rapid T2Bacteria result could have allowed for more informed treatment decisions, including the initiation of earlier effective therapy over 30 hours sooner.

A 91-year-old female presented to the emergency department with several day history of fever, chills, and nausea/vomiting.

Had the T2Bacteria^® test been performed and the result been reported immediately after collection, the patient could have potentially avoided premature discharge and readmission.

Discussion

Upon presentation to the emergency department, the patient was initially given ceftriaxone for the treatment of suspected urinary tract infection. At the time of admission, she had blood and urine cultures obtained, and T2Bacteria ordered. Patient selection for T2Bacteria testing was based on procalcitonin at the time of presentation.

The patient was discharged prior to blood culture resulting in positive for growth (T2Bacteria results were not reported as this case was part of an observational study). Had the T2Bacteria test been performed and the result been reported immediately after collection, the patient could have potentially avoided premature discharge and readmission.

Presentation

A 91-year-old female presented to the emergency department with several days of fever, chills, and nausea/vomiting. The patient was admitted with orders for blood cultures, T2Bacteria, urine cultures, and antibiotics.

Patient Selection Criteria

Procalcitonin 1.5 ng/ml in a patient suspected of bloodstream infection.

Evaluation and Treatment Decision

Diagnosis

Suspected urinary tract infection

Empiric Therapy

Ceftriaxone x 1 dose

Ceftriaxone was chosen for coverage of common causative gram-negative pathogens identified in UTIs.

T2Bacteria Result

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

Blood Culture Result

E. coli on Day 2

Urine Culture Result

E. coli on Day 2

The patient was discharged in the morning of Day 2 prior to the availability of culture results. The patient returned to the ED on the next day with ongoing fever/chills and was readmitted.

Decision making based on T2Bacteria Result

A rapid T2Bacteria result could have allowed for more informed treatment decisions, including the continuation of antibiotic therapy and avoidance of readmission less than 24 hours after her initial premature discharge.

In this case, T2Candida^® results could have permitted earlier focused therapy and aided with the diagnosis of invasive Candida infection and lead to appropriate antifungal therapy. Unfortunately, the T2Direct Diagnostics^™ results were not in clinical use at the time and not obtained until after patient death.

Patient with insulin-dependent diabetes mellitus, primary sclerosing cholangitis, multiple bacteremic episodes, and recent liver transplant was admitted.

Discussion

T2Candida retrospectively revealed C. albicans/C. tropicalis, even at the beginning of the process when the patient was asymptomatic. This case highlights the potential advantage of T2Direct Diagnostics aiding in the diagnosis of deep-seated infection in an immunosuppressed patient without confirmed infection, even before the onset of symptoms.

The two key findings were that arteritis and thrombosis of the hepatic graft resulted from an undocumented fungal infection in the explanted liver and that T2Candida was a suitable diagnostic tool for the diagnosis of deep-seated invasive candidiasis in the absence of positive blood culture results.

Presentation

A 57-year-old woman with insulin-dependent diabetes mellitus, primary sclerosing cholangitis, multiple bacteremic episodes, and recent liver transplant was admitted for sudden abdominal pain. After identification of intrahepatic abscesses the patient underwent a second liver transplant. Subsequently, non-purulent inflammatory tissue was observed in the liver with extensive clotting of the portal vein and hepatic artery and generalized hepatic ischemia. In the following hours, the patient developed graft failure, severe coagulopathy, and died.  

Evaluation and Treatment Decision

All of the cultures collected before death, including blood (obtained at admission and repeated 3 times during hospitalization), ascitic fluid at admission, and liver and abdominal tissues during the re-transplantation procedure, were sterile.

Final Diagnosis

Liver abscess

Empiric Therapy

(May 31, 2017) Vancomycin, meropenem, caspofungin

T2Candida Panel Result

Retrospective T2MR performed on blood samples obtained on May 27^th, May 31^st, June 9^th, June 16^th, and June 26^th showed C. albicans/C. tropicalis were present in all samples.

Histology Result

Histopathology of explanted liver tissue revealed multiple ischemic areas with abundant filamentous fungal structures in their interior, and C. albicans was identified using multiplex PCR.

Decision making based on T2Candida Result

T2Candida result from May 27^th (and subsequent results) could have permitted earlier focused therapy and aided with the diagnosis of invasive Candida infection. Unfortunately, the T2Direct Diagnostics results were not in use clinically and not obtained until after death.

The patient presents to the Emergency Department from a nursing home with a fever, dyspnea, and altered mental status.

Discussion

At the time of admission, this patient had blood cultures obtained, and T2Bacteria ordered. At Piedmont Columbus Regional, patient selection for T2Bacteria testing was based on >2 SIRS criteria PLUS suspected source of infection PLUS hypotension or altered mental status. This patient was positive for 2 of 4 SIRS criteria and had a suspected cause of infection and altered mental state, thus meeting the criteria for testing.

Determination of the causative organism for this patient’s infection allowed optimization of the antibiotic regimen within 24 hours of presentation. The patient was not improving on empiric therapy and experienced clinical improvement after the switch from ceftazidime to meropenem. Additionally, clindamycin was discontinued on Day 2, and vancomycin was discontinued on Day 3 allowing for 5 days of therapy to be saved for clindamycin and 4 days of therapy to be saved for vancomycin. The patient continued to improve and was discharged back to the nursing home after meropenem therapy was completed.

Presentation

PS is a 69 y/o M who presented to the Emergency Department from a nursing home with a fever, dyspnea, and altered mental status. His initial lactic acid was 4.5. The treating physician saw him, and sepsis was suspected. PS was admitted with orders for labs, blood cultures, T2Bacteria^®, and broad-spectrum antibiotics.

Patient Selection Criteria

SIRS criteria:

• Temperature: 103.5˚F
• Heart Rate: 130 bpm
• Respiratory Rate: 20
• WBC (initial): 19,920/mm³

Evaluation and Treatment Decision

Suspected aspiration pneumonia vs. HCAP

Empiric Therapy

Vancomycin, Clindamycin, Ceftazidime

T2Bacteria scheduled to result at 2030 on second shift. Result: K. pneumonia (time to result: ~5 hours), result reviewed by ID pharmacist next am

Blood Culture Result

Negative after 5-days incubation

WBC next am on Ceftazidime: 24,950/mm³ (worsening)

Decision making based on T2Bacteria Result

1. Reviewed internal antibiogram. Changed Ceftazidime to Meropenem based on antibiogram percent susceptibility of 88% vs. 99%.
2. Discontinue Clindamycin and vancomycin
3. WBC next am after the switch to Meropenem: 10,960/mm³

The patient presents with suspected sepsis.

Discussion

Upon admission, the patient was initially given a broad-spectrum antibiotics linezolid, aztreonam, and metronidazole for the treatment of suspected intra-abdominal sepsis. Due to the patient’s recent healthcare exposure, she was at risk for organisms such as MRSA (methicillin-resistant Staphylococcus aureus) and Pseudomonas aeruginosa in addition to the more common causes of intra-abdominal infection such as enterobacteriaceae and anaerobic organisms. 

At the time of admission, she had blood cultures obtained, and T2Bacteria ordered. At Lee Health patient selection for T2Bacteria testing was based on the NEWS (National Early Warning Score) scoring system. The NEWS score was developed to standardize the approach to detection of clinical deterioration in acutely ill patients in the United Kingdom, and a score of 7 or higher puts the patient in the high-risk category. This patient also was positive for 3 of 4 SIRS criteria and had a qSOFA score of 2, indicating a high risk of mortality.

Due to the negative blood culture (T2Bacteria results were not reported as this case was part of an observational study), the patient remained on empiric therapy for 5 days and then was changed to oral therapy and discharged 2 days later. Had the T2Bacteria result been reported, the patient could have been changed to meropenem to cover the E. coli and P. aeruginosa, allowing discontinuation of aztreonam. Given the S. aureus was negative, linezolid could have been discontinued as well. Discontinuation of these two antibiotics within the first 24 hours of admission would have led to ~$6,000 savings in antibiotic charges, and potentially led to earlier discharge on effective oral therapy.

Presentation

53-year-old immunocompromised, morbidly obese female with a recent history of surgery to drain an intra-abdominal abscess. The patient presented at the emergency department 8 days post-op with fever, chills, and abdominal pain. Sepsis was suspected, and the patient was admitted with orders for blood cultures, T2Bacteria^®, and broad-spectrum antibiotics.

Patient Selection Criteria

SIRS criteria:

• Temperature: 103.4
• Heart Rate: 133 BP90/62
• Respiratory Rate: 34
• WBC: 6,800/mm³
• NEWS Score: 9
• QSOFA Score: 2

Evaluation and Treatment Decision

Diagnosis 

Suspected Intra-abdominal sepsis

Empiric Therapy

Linezolid, Aztreonam, Metronidazole

Linezolid was chosen for gram-positive coverage due to challenges with vancomycin dosing in obese patients. Aztreonam was chosen for gram-negative coverage due to the patient history of penicillin allergy. Metronidazole was chosen for anaerobic coverage.

T2Bacteria Result

Positive for E. coli and P. aeruginosa and negative for S. aureus, E. faecium, and K. pneumoniae. (SA -, PA + & EC +); T2Bacteria results were not reported as this case was part of an observational study.  

Blood Culture Result

Negative

Decision making based on T2Bacteria Result

The negative S. aureus result meant that the patient did not have MRSA and therefore, linezolid could have been discontinued after the first dose when the T2Bacteria result was available, a 4.5-day reduction in linezolid. The patient’s therapy could have been more targeted gram-negative coverage by switching to meropenem to cover E. coli and P. aeruginosa