Dimitrios Farmakiotis

Dr. Dimitrios Farmakiotis

The Warren Alpert Medical School of Brown University, Providence, RI, United States
orcid

Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 March 2016 in Infectious Disease Clinics of North America
Verified
Journal Article
Closed access
DFDimitrios Farmakiotis
Dimitrios Farmakiotis
DKDimitrios P. Kontoyiannis
Dimitrios P. Kontoyiannis

1 May 2021 in International Journal of Infectious Diseases
Verified
Journal Article
Open access
MTMaria Tsikala-Vafea
Maria Tsikala-Vafea
NBNeel Belani
Neel Belani
KVKendra Vieira
Kendra Vieira
HKHina Khan
Hina Khan
DFDimitrios Farmakiotis
Dimitrios Farmakiotis
Observational and experimental studies suggest that the use of antibiotics close to administration of immune checkpoint inhibitors (ICI) can have a negative effect on tumour response and patient survival, due to microbiome dysbiosis and the resultant suppression of host immune response against neoplastic cells. A systematic search of PUBMED and EMBASE was undertaken for studies published between 1 January 2017 and 1 June 2020, evaluating the association between the use of antibiotics and clinical outcomes in patients with cancer treated with ICIs. A meta-analysis of the association between the use of antibiotics and clinical outcomes was also performed. Forty-eight studies met the inclusion criteria (12,794 patients). Use of antibiotics was associated with shorter overall survival [hazard ratio (HR) 1.88, 95% confidence interval (CI) 1.59-2.22; adjusted HR 1.87, 95% CI 1.55-2.25] and progression-free survival (HR 1.52, 95% CI 1.36-1.70; adjusted HR 1.93, 95% CI 1.59-2.36), decreased response rate [odds ratio (OR) 0.54, 95% CI 0.34-0.86] and more disease progression (OR 2.00, 95% CI 1.27-3.14). The negative association between the use of antibiotics and progression-free survival was stronger in patients with renal cell carcinoma or melanoma compared with lung cancer. Only antibiotic administration >1 month prior to ICI initiation was associated with increased disease progression. Heterogeneity was substantial for all outcomes. Recent use of antibiotics in patients with cancer treated with ICIs was associated with worse clinical outcomes. Such patients may benefit from dedicated antimicrobial stewardship programmes.

1 September 2017 in International Journal of Antimicrobial Agents
Verified
Journal Article
Closed access
DFDimitrios Farmakiotis
Dimitrios Farmakiotis
Dimitrios P. KontoyiannisDimitrios P. Kontoyiannis
Dimitrios P. Kontoyiannis

10 October 2020 in Diagnostics
Verified
Journal Article
Open access
PDF file
AAAnna Apostolopoulou
Anna Apostolopoulou
ZGZerelda Esquer Garrigos
Zerelda Esquer Garrigos
PVPrakhar Vijayvargiya
Prakhar Vijayvargiya
RLRiver Lerner
River Lerner
DFDimitrios Farmakiotis
Dimitrios Farmakiotis
In this systematic review, we investigate the epidemiology, pathogenesis, risk factors, clinical manifestations, diagnosis and treatment of COVID-19-associated pulmonary aspergillosis (CAPA). We identified 85 cases from 22 studies. The frequency of CAPA is currently unknown but ranges between 30% in different case series; the possibility of colonization rather than invasive disease is the most important confounder. The vast majority of patients with CAPA did not have any of the classic host risk factors, such as immunosuppression from organ transplant or neutropenia, although a significant proportion (46%) had received corticosteroids. Age, pulmonary comorbidities and male sex were associated with higher mortality. Patients treated with voriconazole had numerically lower case-fatality rate. Clinical vigilance for CAPA is advisable in critically ill patients with COVID-19 who are not improving, even those who do not meet classic host criteria for invasive mycoses, especially if they are receiving corticosteroids. A thorough, multi-faceted diagnostic work-up and early initiation of a mold-active triazole may be lifesaving. Further research studies using standardized, uniform definitions of invasive disease and colonization are urgently needed.

17 January 2020 in BMC Infectious Diseases
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Journal Article
Open access
PDF file
RRRalph Rogers
Ralph Rogers
KSKapil Saharia
Kapil Saharia
ACAditya Chandorkar
Aditya Chandorkar
ZWZoe F. Weiss
Zoe F. Weiss
KVKendra Vieira
Kendra Vieira
DFDimitrios Farmakiotis
Dimitrios Farmakiotis
Background: Cytomegalovirus (CMV) infection is one of the most common opportunistic infections following organ transplantation, despite administration of CMV prophylaxis. CMV-specific T-cell immunity (TCI) has been associated with reduced rates of CMV infection. We describe for the first time clinical experience using the CMV T-Cell Immunity Panel (CMV-TCIP), a commercially available assay which measures CMV-specific CD4+ and CD8+ T-cell responses, to predict clinically significant CMV events. Methods: Adult (> 18-year-old) patients with CMV-TCIP results and ≥ 1 subsequent assessment for CMV DNAemia were included at Brown University and the University of Maryland Medical Center-affiliated hospitals between 4/2017 and 5/2019. A clinically significant CMV event was defined as CMV DNAemia prompting initiation of treatment. We excluded indeterminate results, mostly due to background positivity, allogeneic hematopoetic cell transplant (HCT) recipients, or patients who were continued on antiviral therapy against CMV irrespective of the CMV-TCIP result, because ongoing antiviral therapy could prevent a CMV event. Results: We analyzed 44 samples from 37 patients: 31 were solid organ transplant recipients, 4 had hematologic malignancies, 2 had autoimmune disorders. The CMV-protection receiver operating characteristic (ROC) area under the curve (AUC) was significant for %CMV-specific CD4+ (AUC: 0.78, P < 0.001) and borderline for CD8+ (AUC: 0.66, P = 0.064) T-cells. At a cut-off value of 0.22% CMV-specific CD4+ T-cells, positive predictive value (PPV) for protection against CMV was 85% (95%CI 65–96%), and negative predictive value (NPV) was 67% (95%CI 41–87%). Conclusions: The CMV-TCIP, in particular %CMV-specific CD4+ T-cells, showed good diagnostic performance to predict CMV events. The CMV-TCIP may be a useful test in clinical practice, and merits further validation in larger prospective studies.

30 December 2022 in American Journal of Transplantation
Verified
Journal Article
Open access
EKElizabeth J. Klein
Elizabeth J. Klein
AHAnna Hardesty
Anna Hardesty
KVKendra Vieira
Kendra Vieira
DFDimitrios Farmakiotis
Dimitrios Farmakiotis
Organ transplant recipients may not mount an adequate immune response to COVID-19 infection and therefore may benefit greatly from passive immunization with anti-spike monoclonal antibodies (mAbs), which have been shown to decrease hospitalization rates in the general outpatient population. We evaluated the efficacy of mAb therapy in decreasing hospitalizations or emergency room (ER) visits among kidney transplant recipients (KTR) with COVID-19. We identified KTR with COVID-19 between March 1, 2020 and April 30, 2021. Patients were excluded if they had multi-organ transplant or hospital-acquired COVID-19. We studied 95 KTR; 20 received mAb. mAb administration was associated with a significant decrease in hospitalizations or ER visits (15% vs. 76%, p < 0.001). This association remained significant after adjustment for potential confounders, and analysis of mAb administration as a time-dependent variable, with day of symptom onset as day 1 (adjusted HR 0.216, p = 0.04). Black or Hispanic patients were less likely to receive mAb and more likely to be admitted to the hospital or visit the ER. In our KTR population, mAb therapy for COVID-19 may have helped decrease hospitalizations and ER visits. Healthcare inequities, including access to investigational treatments, have been exacerbated by the COVID-19 pandemic. Antiviral mAbs are a promising therapeutic modality, especially for immunocompromised patients.