Infectious disease specialist consultations in a Japanese cancer center: a retrospective review of 776 cases

Beyond Infection: Mortality and End-of-Life Care Associated With Infectious Disease Consultation in an Academic Health System

BACKGROUND

Infectious diseases (ID) physicians are increasingly faced with the challenge of caring for patients with terminal illnesses or incurable infections.

METHODS

This was a retrospective cohort of all patients with an ID consult within an academic health system from 1 January 2014 through 31 December 2023, including community, general, and transplant ID consult services.

RESULTS

There were 60 820 inpatient ID consults (17 235 community, 29 999 general, and 13 586 transplant) involving 37 848 unique patients. The number of consults increased by 94% and the rate rose from 5.0 to 9.9 consults per 100 inpatients (P < .001). In total, 7.5% of patients receiving an ID consult died during admission and 1006 (2.6%) of patients were discharged to hospice. In-hospital mortality was 5.2% for community ID, 7.8% for general ID, and 10.7% for transplant ID patients (P < .001). Six-month mortality was 9% for all nonobstetric admissions versus 19% for community ID, 20.9% for general ID, and 22.3% for transplant ID. In total 2866 (7.6%) of all patients receiving ID consultation also received palliative care consultation during the same hospitalization. The index ID consult preceded any palliative consult in the majority (69.5%) of cases. A total of 16.3% of patients had a do-not-resuscitate order during the index hospitalization; 12.2% of all patients with a do-not-resuscitate order had this placed on the same day as the ID consult.

CONCLUSIONS

Patients receiving ID consultation were increasingly complex and more likely to die soon after consultation. These results provide a framework for ID clinicians to consider their role in end-of-life care.

Comparison of disease and economic burden between MRSA infection and MRSA colonization in a university hospital: a retrospective data integration study

BACKGROUND

Although there is a growing concern and policy regarding infections or colonization caused by resistant bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), the prognosis of MRSA infections compared to that of methicillin-susceptible Staphylococcus aureus (MSSA) infections remains controversial. Moreover, there have not been any studies comparing both the burden of disease and its impact on the healthcare economy between MRSA infection and colonization while adjusting for confounding factors. These comparisons are crucial for developing effective infection control measures and healthcare policies. We aimed to compare the disease and economic burden between MRSA and MSSA infections and between MRSA infection and colonization.

METHODS

We retrospectively investigated data of 496 in-patients with MRSA or MSSA infections and of 1178 in-patients with MRSA infections or MRSA colonization from a university hospital in Japan from 2016 to 2021. We compared in-hospital mortality, length of stay, and hospital charges between in-patients with MRSA and MSSA infections and those with MRSA infections and MRSA colonization using multiple regressions. We combined surveillance data, including all microbiological test results, data on patients with infections, treatment histories, and clinical outcomes, to create the datasets.

RESULTS

There was no statistically significant difference in in-hospital mortality rates between matched MRSA vs. MSSA infections and MRSA infection vs. colonization. On the contrary, the adjusted effects of the MRSA infection compared to those of MSSA infection on length of stay and hospital charges were 1.21-fold (95% confidence interval [CI] 1.03-1.42, P = 0.019) and 1.70-fold (95% CI 1.39-2.07, P < 0.00001), respectively. The adjusted effects of the MRSA infection compared to those of MRSA colonization on length of stay and hospital charges were 1.41-fold (95% CI 1.25-1.58, P < 0.00001) and 1.53-fold (95% CI 1.33-1.75, P < 0.00001), respectively. Regarding confounding factors, hemodialysis or hemofiltration was consistently identified and adjusted for in the multiple regression analyses comparing MRSA and MSSA infections, as well as MRSA infection and MRSA colonization.

CONCLUSIONS

MRSA infection was associated with longer length of stay and higher hospital charges than both MSSA infection and MRSA colonization. Furthermore, hemodialysis or hemofiltration was identified as a common underlying factor contributing to increased length of stay and hospital charges.

Improving diagnostic accuracy of blood culture-positive cases in a cancer center via an antimicrobial stewardship program and infectious disease consultations

The direct impact of antimicrobial stewardship programs (ASP) and infectious disease (ID) consultations on patients' clinical diagnoses remains unknown. We assessed their influence on improving the diagnostic accuracy of blood culture-positive inpatients at a Japanese cancer center. Our single-center, retrospective observational study was conducted from April 1, 2018 to March 31, 2022 to evaluate two phases: pre-intervention (notification of antimicrobials by the infection control team) and post-intervention (ASP implementation and ID consultation service establishment). There were 42,514 inpatients: 22,096 during the pre-intervention and 20,418 during the intervention periods. A total of 939 blood culture-positive episodes (pre-intervention, n = 434; post-intervention, n = 505) were analyzed. During the pre-intervention period, 28.1% of the patients had an unknown diagnosis, which decreased significantly to 1.2% post-intervention. Furthermore, hepatobiliary tract and other infections increased significantly post-intervention, and the mortality rate due to Staphylococcus aureus infection decreased from 28.6% pre-intervention to 10.4% post-intervention. The trend and level of the total number of culture specimens submitted per 1000 patient days for all culture specimens increased significantly post-intervention. Notably, the two-set rate of monthly blood cultures increased significantly. In conclusion, improving the overall diagnostic process with ASP and ID consultations at cancer centers could lead to the optimization of patient care.

Non-infectious diseases in infectious disease consultation: A descriptive study in a tertiary care teaching hospital

In this retrospective study, we aimed to investigate the frequency, trend, and nature of non-infectious diseases (non-IDs) as the final diagnosis for patients during an infectious disease (ID) consultation in an acute care hospital in Japan. This study included adult inpatients who underwent ID consultations between October 2016 and March 2018. The demographic data, clinical manifestations, and final non-ID diagnoses of cases were explored. Among the 502 patients who underwent ID consultations, 45 (9.0%) were diagnosed with non-IDs. The most common diagnoses were tumors (22.2%, n = 10), connective tissue and collagen vascular diseases (13.3%, n = 6), other inflammatory diseases (8.9%, n = 4), and drug-induced fever (8.9%, n = 4). Multiple logistic regression analysis showed that the presence of consultations for diagnosis (odds ratio [OR], 22.0; 95% confidence interval [CI], 10.1-48.2; p<0.01), consultations from the internal medicine department (OR, 2.5; 95% CI, 1.2-5.2; p = 0.02), and non-bacteremia cases (OR, 5.2; 95% CI, 1.4-19.3; p = 0.01) were independently associated with diagnosed non-IDs. Non-IDs after ID consultations were mainly tumor-related, inflammatory diseases, and drug fever. The presence of consultations for diagnosis, consultations from the internal medicine department and non-bacteremia cases were related to non-IDs among ID consultations. Further research is needed to explore the frequency and pattern of non-IDs to improve the quality of ID consultations in daily practice.

Reduction strategies for inpatient oral third-generation cephalosporins at a cancer center: An interrupted time-series analysis

Oral third-generation cephalosporins (3GCs) are not recommended for use owing to their low bioavailability and the risk of emergence of resistant microorganisms with overuse. A standardized and effective method for reducing their use is lacking. Here, in a 60-month, single-institution, interrupted time-series analysis, which was retrospectively conducted between April 1, 2017, and March 31, 2022, we evaluated the effectiveness of a four-phase intervention to reduce the use of 3GCs in patients at a cancer center: Phase 1 (pre-intervention), Phase 2 (review of clinical pathways), Phase 3 (establishment of infectious disease consultation service and implementation of antimicrobial stewardship program), and Phase 4 (educational lecture and pop-up displays for oral antimicrobials at the time of ordering). Although no significant changes were observed in Phases 3 and 4, the first intervention resulted in a significant decrease in the trend and level of days of therapy (DOT) for 3GCs. The level for cephalexin DOT and the trend for sulfamethoxazole-trimethoprim DOT increased in Phase 4, and the trend for amoxicillin and amoxicillin-clavulanate DOT increased in Phase 3. Macrolide DOT showed a decreasing trend in Phases 2 and 4 and decreasing and increased levels in Phases 3 and 4, respectively; no change was observed for quinolones. Actual and adjusted purchase costs of 3GCs decreased significantly during all study periods, while those for oral antimicrobials decreased in Phase 2, and actual purchase costs increased in Phases 3 and 4. No significant reduction in resistant organisms, length of hospital stay, or mortality was observed. This is the first study on the effects of oral 3GC reduction strategies in patients with cancer. We conclude that even facilities that substantially use antimicrobials can efficiently reduce the use of 3GCs.

The importance of infectious disease specialists consulting on a weekly basis in a Japanese tertiary care hospital: A retrospective observational study

Limited data are available regarding part-time infectious disease consultations (IDCs) and their importance in tertiary care teaching hospitals in Japan. This is a retrospective review of IDCs from June 2016 to March 2021 and describes IDC services provided by part-time infectious disease specialists once a week for 4 hours, and their impact on the quality of medical care, including antimicrobial stewardship. Data, such as the requesting department, requesting reasons, and final diagnoses, were analyzed. In April 2018, part-time infectious disease specialists launched consultation services and attended an antimicrobial stewardship team conference. Meropenem, tazobactam/piperacillin, and cefepime monthly days of therapy (DOT) were calculated to assess the effect of each intervention; a pre-post analysis was conducted using the Kruskal-Wallis test. Additional quality improvement (QI) projects related to infectious diseases were implemented. There were 237 IDCs during the study period. Consultations were mostly requested by the General Internal Medicine, Emergency Medicine, and Cardiology departments. The most common diagnoses were bone/joint, respiratory, and genitourinary infections. Infectious disease services, even on a part-time basis, achieve good outcomes in patient management, antimicrobial stewardship, and QI projects. DOT/1000 patient-days were reduced for meropenem and cefepime, while it increased for tazobactam/piperacillin. The DOT/1000 patient-days for the 3-antipseudomonal agents significantly decreased during this period. After implementing the QI tetanus vaccination project in the Emergency Room, the number of tetanus toxoid vaccinations per month increased.

Survey of Inpatient Consultations with General Internal Medicine Physicians in a Tertiary Hospital: A Retrospective Observational Study

Purpose

The general internal medicine (GIM) department can be an effective diagnostic coordinator for undiagnosed outpatients. We investigated the contribution of GIM consultations to the diagnosis of patients admitted to specialty departments in hospitals in Japan that have not yet adopted a hospitalist system.

Patients and Methods

This single-center, retrospective observational study was conducted at a university hospital in Japan. GIM consultations from other departments on inpatients aged ≥20 years, from April 2016 to March 2021, were included. Data were extracted from electronic medical records, and consultation purposes were categorized into diagnosis, treatment, and diagnosis and treatment. The primary outcome was new diagnosis during hospitalization for patients with consultation purpose of diagnosis or diagnosis and treatment. The secondary outcomes were the purposes of consultation with the Diagnostic and Generalist Medicine department.

Results

In total, 342 patients were included in the analysis. The purpose of the consultations was diagnosis for 253 patients (74%), treatment for 60 (17.5%), and diagnosis and treatment for 29 patients (8.5%). In 282 consultations for diagnosis and diagnosis and treatment, 179 new diagnoses were established for 162 patients (57.5%, 95% confidence interval [CI], 51.5-63.3).

Conclusion

The GIM department can function as a diagnostic consultant for inpatients with diagnostic problems admitted to other specialty departments in hospitals where hospitalist or other similar systems are not adopted.

Infectious diseases consultations from general internal medicine physicians in Japan: A descriptive single-center study

In Japan, general internal medicine (GIM) physicians must be aware of frequently encountered infections because of the shortage of infectious disease (ID) specialists. However, there are currently no epidemiological data on this subject. This study aimed to describe the frequency and pattern of ID consultations requested by GIM physicians in Japan. This is a 3-year retrospective review of the ID consultations requested by GIM physicians in Japan at a community-based acute tertiary care teaching hospital in Tokyo from April 2018 to March 2021. Demographic data, such as reasons for consultation, causative organism, and final diagnoses, were collected. During the study period, ID consultations were requested by GIM physicians 128 times. The incidence rates of bacteremia and 30-day mortality were 65.6% (n = 84) and 3.1% (n = 4), respectively. The most common diagnostic classifications after ID consultation were bone/joint (24.2%, n = 31), respiratory (17.7%, n = 22), and cardiovascular infections (12.5%, n = 16). The most common final diagnoses were bacteremia (11.7%, n = 15), infective endocarditis (9.4%, n = 12), and vertebral osteomyelitis (7.8%, n = 10). This is the first study to describe the ID consultation cases requested by GIM physicians in Japan in a community-based acute tertiary care teaching hospital. Despite the shortage of ID specialists, GIM physicians covered a wide range of IDs, including bone/joint infections and infectious endocarditis, which require long-term care. ID and GIM physicians, including hospitalists, should cooperate to promote the quality of care and clinical management. Future multi-center studies with large numbers of clinical cases are needed to determine the ID clinical knowledge required by GIM physicians in Japan.

Outcomes of General Internal Medicine Consultations for Diagnosis from Specialists in a Tertiary Hospital: A Retrospective Observational Study

Purpose

The data on the diagnostic contribution of general internal medicine (GIM) consultations for undiagnosed health problems from specialists are scarce. This study aims to explore the role of generalists as diagnostic medicine consultants in tertiary care settings.

Patients and Methods

We conducted a retrospective observational study at a Japanese university hospital. GIM consultations for diagnosis from other departments on outpatients aged ≧ 20 years from January 2018 to December 2020 were included. Data were extracted from electronic medical records. The primary outcome was new diagnosis rates. The secondary outcomes were new diagnosis rates with clinical significance and clinical outcomes at 90 days from the index visit.

Results

A total of 328 patients were included. The top five consulting departments were orthopedics (17.0%), cardiovascular (10.3%), otorhinolaryngology (8.8%), neurology (8.8%), and gastroenterology (7.9%). GIM identified 456 chief complaints (CCs), and the top five were fever (10.9%), abnormal laboratory results (8.3%), fatigue (5.9%), and pain (7.4%) or numbness (4.6%) in the extremities. There were 139 (104/328 patients: 31.8%) specialty consultations from GIM, and the top five departments were rheumatology (21.1%), gastroenterology (19.2%), orthopedics (9.6%), psychiatry (9.6%), and neurology (9.6%). In total, 277 new diagnoses were established in 232 patients (70.7%), and 203 patients had new diagnoses with clinical significance (61.8%). Clinical outcomes at 90 days from the time of the index visit were resolution/improvement (60.7%), unchanged/worsened (22.3%), and unknown (17.0%).

Conclusion

Over 70% of GIM consultations from other departments established new diagnoses with favorable outcomes in >60% of the patients.

Effects of infectious disease consultation and antimicrobial stewardship program at a Japanese cancer center: An interrupted time-series analysis

In cancer patients, appropriate diagnosis and management of infection are frequently challenging owing to subtle or atypical presentation. We investigated the effectiveness of infectious disease (ID) consultations and the Antimicrobial Stewardship Program (ASP) in a Japanese cancer center. This 36-month-period, single-institution, interrupted time series analysis was retrospectively conducted during April 1, 2018–March 31, 2021, to evaluate a two-phase intervention: Phase 1 (notification of antimicrobials by the infection control team) and Phase 2 (establishing an ID consultation service and implementing ASP). Among 32,202 patients hospitalized, 22,096 and 10,106 hospitalizations occurred at baseline and during intervention period, respectively. The Antimicrobial Stewardship Team (AST) provided feedback on specific broad-spectrum antimicrobials in 913 instances (347 appropriate [38%]; 566 inappropriate [62%]), and 440 ID consultations were completed, with a 75% overall acceptance rate for AST suggestions. In Phase 2, monthly carbapenem days of therapy (CAR-DOT) decreased significantly, and narrow-spectrum antibiotic usage increased significantly in both trend and level; monthly DOT of antipseudomonal agents decreased significantly in trend. The results of these analyses of antimicrobial use are consistent with the DOT-based data based on antimicrobial use density (AUD). The total number of inpatient specimens increased significantly; the trend of multidrug-resistant Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus infections decreased, without changes in the incidence of other resistant organisms, all-cause in-hospital mortality, and length of stay. Actual and adjusted CAR purchase costs per patient-day decreased without significant changes in the actual and adjusted purchase cost per patient-day for all intravenous antimicrobials. Combining ID consultation and ASP reduced carbapenem use without negative patient outcomes. Their implementation could facilitate establishment of safe cancer treatment facilities in Japan and improve prognosis in cancer patients.