Presentation is loading. Please wait.

Presentation is loading. Please wait.

1 Dr Anita Verma MD Consultant Microbiologist Department of Medical Microbiology & Institute of Liver Studies, King’s College Hospital, Foundation, NHS.

Similar presentations


Presentation on theme: "1 Dr Anita Verma MD Consultant Microbiologist Department of Medical Microbiology & Institute of Liver Studies, King’s College Hospital, Foundation, NHS."— Presentation transcript:

1 1 Dr Anita Verma MD Consultant Microbiologist Department of Medical Microbiology & Institute of Liver Studies, King’s College Hospital, Foundation, NHS trust, London

2 Conflict of interest  Educational grant and Speakers – Gilead, Astellas  Investigator and speaker for a study - Pfizer

3 Challenges in Management of Invasive Fungal Infections (IFI) in Immunocompromised (IC) Patients New mycologic challenges in IC pateints  Know the Changing Epidemiology of IFI  Nonspecific presentation of IFI  Inadequate diagnostic methods  Antifungal prophylaxis – Does it work ?  Breakthrough Infections while on antifungal therapy  Refractory to antifungal treatment 3

4 Background: IFI in Immunocompromised Patients  IFI incidence is increasing in immunocompromised (IC) hosts (SOTR & HSCT recipients ) because of  The pool of IC patients is increasing dramatically  external pressures from antibiotic usage  use of newer and more potent chemotherapeutic agents  their highly compromised immune status SOTR: solid organ transplants recipients, HSCT recipients : hematopoietic stem cell

5 Epidemiology of IFI in both SOTR & HSCT Recipients Increasing incidence of mold infections SOTRHSCT Invasive candidiasis53%28% Invasive aspergillosis19%43% Cryptococcosis8%- Non-aspergillus molds8%- Endemic fungi (5%)5%- Zygomycosis2%- The Transplant-Associated Infections Surveillance Network (TRANSNET) -23 transplant centers in the US, prospective study from 2001 to 2006: epidemiology of IFI in both SOTR and HSCT recipients Clin Infect Dis. 2010, 50:1101–11, Clin Infect Dis. 2010, 50:1091–100.

6 Invasive Aspergillosis Type ofIA,%DisseminatedMortality transplantrange (mean)aspergillosis, %rate, % Liver1-8 (2)50-6092 Lung3-14 (6)15-2074 Heart1-15 (5.2)20-3578 Kidney0.9 - 0 4 (.7)9-3677 Pancreas1.1 - 2.9 (1.3)NA100 Small bowel0 - 3.6% (2.2)NA100

7 Mortality Of Invasive Aspergillosis in Relation To Underlying Disease Clin Infect Dis 2001;32:358 100908070605040302010 leukemia leukemia /lymphoma /lymphoma bone marrow transplant bone marrow transplant kidney transplant kidney transplant lung /heart lung /heart liver transplant liver transplant AIDS AIDS

8 Inadequate Current diagnostic methods for IFI >30% Detected on autopsy  In a case series involving patients with hematologic malignancy  IFI high prevalence of IFI 31% detected at autopsy  77% of the patients’ deaths were related to infection  This highlighted the inadequacies of current diagnostic methods for IFI Haematologica. 2006, 91:986–9

9 Current limitations of classical and new Diagnostic test for IFI- Issuses Conventional methods of Microscopy and culture rarely positive because: Invasive Candidiasis (IC)  Patients on antifungal prophylaxis  Imaging not helpful  Diagnosis is mainly clinical Invasive Aspergillosis (IA);  Initially affects the lungs, easily go unoticed because no clinical symptoms  Even when recognized early, suitable specimens can be difficult to obtain  In LTR pts with IA - 50% who had Aspergillus in BAL,22 fold at risk of IA (Singh et al 1997) Lack of adequate diagnoses makes estimating the prevalence and incidence of IFI unreliable

10 Diagnosis: Imaging- Invasive Aspergillosis  Chest X-ray- nodular lesions, interstistial opacities, cavitary lesions, or pulmonary embolus pattern, or normal chest x-ray  CT- valuable when chest –x-ray negative, can reveal disease as much as 5 days earlier An 18-month-old girl - Aspergillus isolated from the lung. (a) Chest radiograph showed a round opacity behind the heart. (b) CT revealed a cavitating nodule in the left lower lobe.

11 Nonspecific Presentation In Immunocompromised Patients- Case Scinario  18 yrs M LCH, had BMT  Admitted for Liver transplant - D1 post LTx - Ambisome -5mg/kg x7 days (fullfill criteria highrisk for mold infection)  Persistant Neutropenia  Changed to caspofungin ( half dose because of abnormal LFTS)  D18 post LT - multiple cutaneous lesions  Prior to LTX multiple courses of antifungal  Previous lung Bx before LTx -ve  Skin Biopsy- + hyphae  Culture- Aspergilllus fumigatus  Started on voriconazole + Ambisome  No response x 4 weeks  Immunomodulation- leukocyte infusion  Resolution of skin lesion – negative for mold  However 3 month later relapse of underlying dis (LCH)- BX proven Wright stain;hyphae

12 Available Non Culture Methods Detection of circulating surrogate markers. 1.Serological tests - detect fungal antigens  Aspergillus galactomannan ELISA  (1 → 3)- β-D- glucan  Mannan & anti-Mannan antibody 2. PCR-based assays - detect fungal DNA. 3. Imaging

13 Serological test: β-D- glucan (BDG)  Cell wall component of wide variety of fungi (not zygomycetes or Cryptococcus).  Indicated for the presumptive diagnosis of IFI  Sensitive with a good negative predictive value i.e. good for excluding infection.  A review of 23 & meta-analyses of 16 studies containing 2979 patients gave a pooled sensitivity of 76.8% & specificity of 85.3%. (Clin Infect Dis 2011;52(6):750-70. )  Meta-analysis of 31 studies of IFD: sensitivity (80%) & specificity (82%) was found by a (excluding Pneumocystis infection). (J Clin Microbiol 2012; 50(1):7-15. )

14 ANTIFUNGAL STEWARDSHIP PRE-EMPTIVE TREATMENT BASED ON BDG+ RISK FACTORS

15 Intensive care unit (ICU) stay - >9 month No pos culture, ?suspected aspergillosis based on BDG+ risk factors pre-emptive treatment for IA Risk factors for IFI ALF of unknown cause Intra-abdominal bleed, bowl perf, pancreatitis, dialysis dependent, multiple viral infction adeno, CMV, EBV Augmneted immunosuppression ICU stay >1year

16 Optimal Antifungal Strategy – no uniform consensus ? Invasive Fungal InfectionsIssues Prophylaxis- most effectiveVariable practice Emperical: possible- Serology+ clinical ? Which antifungal ?Duration Pre-emptive: probable infection- serology+ radiology + clinical Specific Treatment : above + tissue diagnosis- proven infection- ? role of combination therapy

17 T erbinafine AmBisome Griseofulvin Fluconazole Amphocil Abelcet I traconazole Licensed Antifungals 0 2 4 6 8 10 12 195019601970198019902000 Amphotericin B Nystatin Ketoconazole Miconazole 5-Flucytosine 2010 14 Voriconazole Posaconazole Caspofungin Micafungin Anidulafungin

18 Current Practices- Institutional practices of antifungal prophylaxis vary widely Survey by Singh etal LTX R (Am J Transplant 2008:8:426-31) 67 sites participated 70% performed >50 transplants annually 106 UNOS Approved Transplant Programmes 72%targeted towards high risk patients 28% used universal prophylaxis 91% employed some sort of Prophylaxis 86% used Fluconazole 14% either Ambisome 1mg/kg /or echinocandins was used mainly for mold Antifungal choices Duration of Prophylaxis 40% centres till hospital stay 20% for 1month 10% fo 3month Remainder for varied duration

19 Risk of Antifungal Prophylaxis in Current Era  Over one-third of the infections due to non-albicans Candida spp.  Prior antifungal prophylaxis the only risk-factor for non-albicans Candida Spp 58% for non-C.albicans, and 22.7% for C. albicans infections;  Mortality 25 fold higher for cases than for controls (p = 0.0002); 58% for non-C.albicans, and 22.7% for C. albicans infections;  Azole resistance due to prior fluconazole usuage;Husain et al., Transplantation 2003; 27: 2023-2029

20 Ecological Shift: Candidaemia in a specialist ICU 10 years epidemiology 20

21 21 Invasive candidiasis due to C albicans – Refractory to Fluconazole and Ambisome Sex/ age Underlyi ng disease Risk factors Anti- fungal Prophyl axis Initial treatmentChanged to Respons e Conco mitant infectio ns 1 M 5 Yr BA, D20 Post, LTx BP, BL drains in situ Flucona zole 6mg/kg x 2wks Ambisome 3mg/kg + fluconazole 12mg/kg x 3wks Echinocandin Cleared after 2wks VRE +EBV 2 M 16 yr 2yr post tx Bowel perf, BL, drains in situ, Flucona zole- 400mg Ambisome 3mg/kg + fluconazole 12mg/kg x 3wks Echinocandin Cleared after 10 days CMV + HSV Presentation of Fungal infection –intrabdominal due to C albicans, BA –Biliary atresia, BP- bowel perforation, LTx – Liver transplant, BL-Biliary leak, C albicans came back very sensitive MICS value with normal range Refractory to Antifungal Treatment

22 22 ‘Cerebral Aspergillosis While on Antifungal therapy Sex/ age Liver disease Presentation of FI after LTx Site of FI Anti-fungal Therapy Risk factors Treatment Outcome 1 F 51PBC Brain Lesion on week 11 Brain Ambisome 3mg/kg Chronic LF, & RF Ambisome+ Voriconazole alive 2 F 50 ALF (Drug) Chest infection on week 3 Lung, Brain CaspofunginPNG, RF Ambisome+ Voriconazole *Deceased 3 M 33 ALF (POD) Chest infection on week 3 Lung, Eye, Brain Caspofungin Acute RF, Re- Tx Ambisome+ Voriconazole Alive FI; Fungal infection, ALF; acute liver falure, LF; Liver failure, RF;renal failure, PBC; primary biliary cirrhosis, PNG; primary nonfunctoning graft, LTx; Liver transplantation *patient 2 – had 9 month of treatment IA was treated however diedwhile awaiting for 2 nd tx - because of graft failure and bacterial septic shock Breakthrough Infections

23 New Mycologic Challenges  Refractory to treatment develop breakthrough - needs further evaluation  Impaired Host immune system-  ?Tissue concentration of antifungals  ? Tolerance  or Drug-resistant  Finally, immune-enhancing strategies such as the  use of growth factors  and/or white blood cell transfusions for the prevention and treatment of opportunistic fungal infections in immunocompromised patients remain an important area of investigation. 23

24 Conclusions: Invasive Fungal Infections Way to improve IFI are-  Selective antifungal prophylaxis- risk based  Aggressive diagnostic approach- nonculture methods  High degree of vigilance  Early pre-emptive therapy  Develop less damaging methods of immune suppression  Immunomodulation in very high risk patients

25 Thank you for your attention


Download ppt "1 Dr Anita Verma MD Consultant Microbiologist Department of Medical Microbiology & Institute of Liver Studies, King’s College Hospital, Foundation, NHS."

Similar presentations


Ads by Google