Post on 25-May-2015
transcript
Fungal infections in critically ill patients
Dr Tim Felton
The University of Manchester
Case study• 24 year old female• Psoriasis with arthropathy• Obesity (110kg)• Admitted to ICU • Methorexate 10mg weekly1. H1N1 pneumonitis2. ARDS3. Pancytopenia4. Severe sepsis
Day 6• Persistent sepsis• Respiratory failure (consider for ECMO)
• Treated with broad-spectrum antibiotics
• Identify Candida tropicalis from airways
Is the Candida culture relevant?What would you do next?
Would you treat?
Day 7
• Identify Candida tropicalis from urine
Is two Candida cultures relevant?What would you do next?
Would you treat (and if so with what)?
Treatment• Day 7
– Fluconazole 400mg daily• Day 14
– Caspofungin 70mg then 50mg
• Day 20 – Ambisome 3mg/kg
• Day 53– RIP
Epidemiology• 4th (9%) most common cause of blood
stream infection in the US (and climbing…)
• 6-10th most common in Europe• Incidence up to 10x higher in ICU
patients• Attributable mortality 49-60%
Candida species in ICU
Bassetti 2006
Comert 2007
Laverdiere 2007
Italy Turkey Canada
C. albicans 40% 66% 72%
C. glabrata 15% 9% 16%
C. parapsilosis 23% 11%
C. tropicalis 9%
Non-albicans Candida species• Increasingly reported as both colonisers and pathogens
• Mortality– C. albicans ≈ 15 to 35%– C. tropicalis and C. glabrata ≈ 40 to 70% – C. parapsilosis ≈ 10 to15%
JoHI (2002) 50:243-260
Risk factors (compared to C. albicans)
C. glabrata (Fluconazole prophylaxis), BMT, Surgery, Solid organ cancer
C. tropicalis BMT, Solid tumours, Intravascular device
C. krusei Neutropenia, Fluconazole prophylaxis, BMT
C. parapsilosis Intravascular device, TPN, BMT, Neonates
C. krusei Fluconazole prophylaxis
C. lusitaniae Polyene use (inducible resistance)
Risk factors for Candidemia
• Older age • Diabetes mellitus• Central venous lines• Mechanical
ventilation• Multiple antibiotics• Parenteral nutrition• Major surgery• Colonization• Candiduria
• Immunosuppression• High APACHE II
(>30)• Prolonged
neutropenia• Uraemia• Haemodialysis• Low cardiac output• Diarrhoea• Extensive burns• Acute pancreatitis
JoHI (2007) 66: 201-206
Diagnostic tests• Blood culture
– Sens 50%, spec 100%• (13)-β-D-glucan
– Sens 70%, spec 87%• PCR
– Sens 90%, spec 100%
Mycoses 2010 53:424-433
Predictive scores• Leon et al. 2006• 1*(total parenteral nutrition)• +1*(surgery)• +1*(multifocal Candida species
colonization)• +2*(severe sepsis)
• Score >2.5• Sensitivity 81%• Specificity 74%
• Ostrosky-Zeichner et al. 2007• Any systemic antibiotic (days
1–3) • OR CVC(days 1–3) • AND at least 2 of the following
– total parenteral nutrition (days 1–3)– any dialysis (days 1–3)– any major surgery (days −7–0)– pancreatitis (days −7–0)– any use of steroids (days −7–3)– or use of other immunosuppressive
agents (days −7–0)
Colonisation scores• Pittet et al. 1994• Colonization index• No. of non-blood body sites colonised
(heavy growth) by Candida spp./total no. of sampled sites
• 100% sensitivity and specificity.
Treatment• Early and appropriate • Mortality (after +ve blood culture)• Day 0 – 15%• Day 1 – 24%• Day 2 – 37%• Later – 41%
Garey et al. 2006 CID 43:25–31
Antifungal susceptibility
Species Fluconazole Voriconazole Flucytosin
eAmphotericin
BEchinocandin
s
C. albicans S S S S S
C. glabrata S – DD to R S – DD to R S S to I S
C. tropicalis S S S S S
C. parapsilosis S S S S S to R
C. krusei R S I to R S to I S
C. lusitaniae S S S S to R S
CID (2009) 48:503–35
Prophylaxis• Reduces rates of colonisation to candidemia• May reduce mortality from candidemia
• Probably helpful if– High levels of candidemia– Other infection controls measures are enforced– High risk individuals
Pfaller et al. 2007. Clin Microbiol Rev 20:133–163
Pre-emptive treatment• Very few studies
• Piarroux et al. 2004• Bases of colonisation index• Reduced rates of invasive candidiasis
(compared to historial controls)• Fluconazole
Piarroux et al. 2004 CCM 32:2443–2449
Treatment
Guery et al. 2009. ICM. 35;206-214
Treatment
Case study• 27 year old female• Known asthmatic• 3/7 increasing SOB, wheeze and cough• Symbicort 200 2 puff bd + Bricanyl 500 prn• No other PMHx (no DM)• Ex-smoker
In A+E• Bronchospasm and tachycopnea• Mild tachycardia and normotension• CXR Hyper-expanded but clear lung fields• Responded to nebs• Clarithromycin 500mg BD (penicillin
allergy)• Prednisolone 40mg od
8 hours later….• Decompensation• ICU - Intubation and MV• Resistant bronchospasm (sedation, muscle
paralysis, ketamine and Sevoflurane)• Day 2 - persistent high grade fever (active
cooling)
Day 4
• Surveillance NBL– Aspergillus fumigatus
• CXR – widespread airspace infiltrates (ALI)
Is the Aspergillus culture relevant?What would you do next?
Would you treat?
Day 5
• Bronchoscopy and BAL – Culture positive for Aspergillus fumigatus. – No evidence of bacteria growth or acid-fast
bacilli.
• Serum Aspergillus PCR +ve.
Is the Aspergillus culture/PCR relevant?What would you do next?
Would you treat (and if so with what)?
Treatment
• Voriconazole (loaded then 4mg/Kg bd) then to PO
• Continued for 6 months (Asp IgG 26)• TDM
with• Caspofungin 70mg then 50mg for 30 days
Follow up• Retrospective Day 0 IgG + IgE to Asp –ve • Day 8 Aspergillus IgG 148 mgA (0-40)• Extubated on day 25• CT (day 31) widespread cavities, ground
glass opacity and bronchiectasis• Environmental cultures –ve• No immune defect found
• 127 of 1850 (6.9%) consecutive medical ICU admissions with IA or colonisation (micro/histol).
• 89/127 (70%) did not have haematological malignancy
• 67/89 proven/probable IA
• 33 of 67 (50%) COPD
• Mortality 80% (Predicted 48%)
AJRCCM. 2004;170: 621
• 36/1756 patients (2%)
• 20 IPA (defined as “pneumonia”)• 14 colonised
• Mortality– Colonisation 50%– IPA 80%
Risk factors in critical illness• Steroids (odds ratio = 4.5)
– Prolonged corticosteroids treatment prior to ICU– Steroid treatment with a duration of 7 days
• Immunosuppressive therapy• Chronic obstructive pulmonary disease (odds ratio = 2.9)• Liver cirrhosis• Solid-organ cancer• HIV• Severe burns• Prolonged stay in the ICU (>21 days)• Malnutrition• Post–cardiac surgery status
Meersseman et al. CID. 2007;45: 205–16
Critical illness – risk factor?
• Compensatory anti-inflammatory response syndrome – Monocyte/macrophage deactivation– Neutrophil deactivation– HLA-DR antigen expression– Loss of antigen-presenting capacity– synthesis of pro-inflammatory cytokines
Environment
• Pulmonary colonisation prior to ICU– Lobectomy, PM for unexpected cardiac death– 30/74 (41%) patients with Aspergillus species
• Environmental contamination– High concentration of air-bourne spores
Lass-Florl et al. BJH. 1999; 104:745-7
Respiratory tract samples• Colonisation or IPA?
• 172 patients, Belgium ICUs, 7 years– 89 colonisation– 83 IPA (EORTC/MSG criteria)
• Poor positive predicative value for IPA• But…………………
• 110 ICU admission, IPA by EORTC/MSG criteria• 1/3 hematological malignancy interpret with care• BAL GM probably useful; Serum GM probably not
AJRCCM . 2008;177: 27-34.
Beware: Piperacillin
- tazobactam
Imaging• CT
– Frequently absent– Halo sign, air
crescent sign and nodules much more common in neutropenic patients
– Difficult to interpret with ARDS
Calliot et al. J Clin Oncol. 1997. 15:139-47
Other diagnostic tests• PCR
– Not evaluated in critically ill patients
• Biopsy– Gold standard– Difficult!
Diagnosis in critical illness• High risk patients• Pulmonary infiltrates and fever, not
responding to appropriate antibacterial agents
• ± some concern that Aspergillus may be a diagnostic possibility– Recent unidentified case which died– Isolation of Aspergillus from respiratory tract
Treatment in ICU• IDSA recommendations but little evidence in
critically ill
• Voriconazole– Hepatotoxicity and nephrotoxicity– IV formulation – cyclodextran– Substrate and inhibitor CYP2C19, 2C9 and 3A4– bioavailabity with fat – requires empty stomach – TDM
Treatment in ICU• Lipid preparations of Amphotericin B
– Less nephrotoxic than deoxycholate
• Eichinocandin– Salvage therapy
• Combination
Summary• Candida and Aspergillus increasingly
recognised as ICU pathogens• Increased morbidity and mortality• High index of suspicion• Diagnostic strategy (clinical, radiology, lab)• Treatment is complicated
– ADR, interactions