Surrogatmarkörer vid invasiva svampinfek4oner Ber4l Christensson Avd för Infek4onsmedicin Lund
Varför surrogatmarkörer? Tidig behandling ger bäbre utläkning och minskad mortalitet (precis som vid svår bakteriell sepsis) Candida blododlingar endast 50% pos. Empirisk behandling Pre- emp4ve behandling (pos surrogatmarkör)
Surrogatmarkörer svamp Betaglukan Galaktomannan (A II för invasiv aspergillos) Mannan, an-- mannan Arabinitol Cryptococcan4gen (A II för cryptococcos) PCR (D III dvs rekommenderas inte)
Riskgrupper Mul4traumapa4enter på IVA Prematura pa4enter på neonatal IVA Neutropena hematologpa4enter Annan immunsuppression, ssk steroider Olika surrogatmarkörer beroende på riskgrupp
Betaglukan Obayashi T et al. Lancet 1995;345:17-20 1-3- beta- D- glucan > 20 pg/ml vid invasiv mykos hos febrila pa4enter på sjukhus Sens: 90% Spec: 100% PV pos 100% PV neg 97% För bra för ab vara sant?? Nej - inte vid PCP!
Varför betaglukan vid PCP (PJP)? Typisk pa4ent Höga steroiddoser (ex CNS- metastaser, Wegener) Tilltagande dyspné, desaturering Improduk4v hosta Klarar inte sputum, bronkoskopi, BAL BG är non- invasiv Nega4vt BG utesluter pneumocys4s ROC- AUC 0,96 (95% CI 0,94-0,99) Slutsats: Strong evidence (A II) (Onishi et al. J Clin Microbiol 2011)
Diagnostic Accuracy of -D-Glucan for PJP and IFI FIG 2 Summary receiver operating characteristic (SROC) curves for Pneumocystis jiroveci pneumonia and invasive fungal infection. Individual study estimates of sensitivity and 1 specificity are represented by the circles. Circle sizes are proportional to study weights; however, sizes are not to scale. The lateral lines represent 95% confidence intervals. lation, no statistically significant differences in the accuracy of the BG assay were noted. Even after the exclusion of studies written in languages other than English and studies in which prophylactic antifungal therapy was not reported or used, the results did not change significantly. In the multivariable metaregression results, DOR was not significantly influenced by language, reference standard, age, or sex. Although we performed sensitivity analysis, stratified analysis, and metaregression based on various factors to determine the source of this majority of heterogeneity among the studies, heterogeneity was still significant. Publication bias. The appearance of funnel plots was asymmetrical, and Egger s test results were significant (P 0.01). This suggested that publication bias may be present. After exclusion of the four studies that included 50 or fewer participants, differences in the accuracy of the BG assay findings were not statistically significant. DISCUSSION Our meta-analysis to examine the diagnostic accuracy of the serum BG assay for PJP and IFI has resulted in several significant findings. First, the BG assay showed the high AUC-SROC for PJP with no heterogeneity. Moreover, the BG assay is not an invasive test. The gold standard for diagnosis is microscopic visualization of the organism, and bronchoalveolar lavage fluid, sputum, or tissue is necessary for diagnosis. Because patients with PJP tend to present with nonproductive or minimally productive cough, sputum is often insufficient for diagnosis and an invasive procedure such as bronchoscopy is needed. Noninvasive BG assay is useful as a screen to avoid unnecessary invasive procedures. Second, we showed that the BG assays have high sensitivity for PJP. The BG assay can therefore be used as a screening tool. If any of the BG assays are negative, PJP can be ruled out and unnecessary procedures or treatments for PJP can be avoided. Third, the pooled specificity was moderate for PJP because the BG assay could be positive for various fungal infections and the presence of factors such as use of intravenous amoxicillinclavulanic acid, treatment of patients with immunological preparations (albumins or globulins), use of cellulose membranes and filters made from cellulose in hemodialysis, and use of cotton gauze swabs/packs/pads and sponges during surgery (8). If the BG assay is positive, it is important to consider the factor associated with false-positive results and exclude IFI by other modalities or invasive procedures such as computed tomography scan and bronchoscopy. Fourth, the diagnostic accuracies for HIV patients and HIVnegative patients were not significantly different. Nakamura and colleagues (42) suggested that the detection rate of BG in HIVnegative patients was lower than that in HIV patients. HIVnegative patients usually have significantly fewer organisms in bronchoalveolar lavage fluid than do HIV patients. This can lead to false-negative results, particularly in HIV-negative patients (8). However, our results showed that the BG assay was useful not only in HIV patients but also in HIV-negative patients. Fifth, the diagnostic accuracy for IFI of the BG assay was moderate, with high statistical heterogeneity. While there are several molecular and serological assays for the diagnosis of specific types of IFI, which can be detected by means of galactomannan, mannan, and DNA sequences (36), only the BG assay can be used for various fungal infections. For instance, the diagnostic accuracy of the galactomannan assay for invasive aspergillosis is similar to that of BG for IFI. Leeflang and colleagues (28) used a meta-analysis to demonstrate that the galactomannan assay had an overall sensitivity of 78% (95% CI, 61% to 89%) and an overall specificity of Downloaded from http://jcm.asm.org/ on February 1, 2012 by LUND UNIVERSITY January 2012 Volume 50 Number 1 jcm.asm.org 13
Betaglukan hematologpa4enter Invasiv svampsjukdom Fungitell, cut- off 60-80 pg/ml 2 konseku4va test: spec nära 100%, sens 45-65% Likvärdigt för candida/aspergillus Inga data om 4ming ROC- AUC 0,88 (95% CI 0,82-0,93) Slutsats: Moderate evidence (B II)
Diagnostic Accuracy of -D-Glucan for PJP and IFI FIG 2 Summary receiver operating characteristic (SROC) curves for Pneumocystis jiroveci pneumonia and invasive fungal infection. Individual study estimates of sensitivity and 1 specificity are represented by the circles. Circle sizes are proportional to study weights; however, sizes are not to scale. The lateral lines represent 95% confidence intervals. lation, no statistically significant differences in the accuracy of the BG assay were noted. Even after the exclusion of studies written in languages other than English and studies in which prophylactic antifungal therapy was not reported or used, the results did not change significantly. In the multivariable metaregression results, DOR was not significantly influenced by language, reference standard, age, or sex. Although we performed sensitivity analysis, stratified analysis, and metaregression based on various factors to determine the source of this majority of heterogeneity among the studies, heterogeneity was still significant. Publication bias. The appearance of funnel plots was asymmetrical, and Egger s test results were significant (P 0.01). This suggested that publication bias may be present. After exclusion of the four studies that included 50 or fewer participants, differences in the accuracy of the BG assay findings were not statistically significant. DISCUSSION Our meta-analysis to examine the diagnostic accuracy of the serum BG assay for PJP and IFI has resulted in several significant findings. First, the BG assay showed the high AUC-SROC for PJP with no heterogeneity. Moreover, the BG assay is not an invasive test. The gold standard for diagnosis is microscopic visualization of the organism, and bronchoalveolar lavage fluid, sputum, or tissue is necessary for diagnosis. Because patients with PJP tend to present with nonproductive or minimally productive cough, sputum is often insufficient for diagnosis and an invasive procedure such as bronchoscopy is needed. Noninvasive BG assay is useful as a screen to avoid unnecessary invasive procedures. Second, we showed that the BG assays have high sensitivity for PJP. The BG assay can therefore be used as a screening tool. If any of the BG assays are negative, PJP can be ruled out and unnecessary procedures or treatments for PJP can be avoided. Third, the pooled specificity was moderate for PJP because the BG assay could be positive for various fungal infections and the presence of factors such as use of intravenous amoxicillinclavulanic acid, treatment of patients with immunological preparations (albumins or globulins), use of cellulose membranes and filters made from cellulose in hemodialysis, and use of cotton gauze swabs/packs/pads and sponges during surgery (8). If the BG assay is positive, it is important to consider the factor associated with false-positive results and exclude IFI by other modalities or invasive procedures such as computed tomography scan and bronchoscopy. Fourth, the diagnostic accuracies for HIV patients and HIVnegative patients were not significantly different. Nakamura and colleagues (42) suggested that the detection rate of BG in HIVnegative patients was lower than that in HIV patients. HIVnegative patients usually have significantly fewer organisms in bronchoalveolar lavage fluid than do HIV patients. This can lead to false-negative results, particularly in HIV-negative patients (8). However, our results showed that the BG assay was useful not only in HIV patients but also in HIV-negative patients. Fifth, the diagnostic accuracy for IFI of the BG assay was moderate, with high statistical heterogeneity. While there are several molecular and serological assays for the diagnosis of specific types of IFI, which can be detected by means of galactomannan, mannan, and DNA sequences (36), only the BG assay can be used for various fungal infections. For instance, the diagnostic accuracy of the galactomannan assay for invasive aspergillosis is similar to that of BG for IFI. Leeflang and colleagues (28) used a meta-analysis to demonstrate that the galactomannan assay had an overall sensitivity of 78% (95% CI, 61% to 89%) and an overall specificity of Downloaded from http://jcm.asm.org/ on February 1, 2012 by LUND UNIVERSITY January 2012 Volume 50 Number 1 jcm.asm.org 13
Intensivvårdspa4enter Invasiv candidiasis 16 av 95 pa4enter med IVA vård över 5 dagar hade invasiv svampinfek4on (14 IC, 2 IA) Betaglukan ROC- AUC: 0,98 PV pos för BG: 72,2 % PV neg för BG: 98,7 % Kolonisa4on ROC- AUC: 0,63 Candida score (TPN, kirurgi, kolonisa4on, svår sepsis): 0,80 (Posteraro et al. Cri4cal Care 2011;15:R249)
Betaglukan på IVA Posi4v BG föregår pos blododling med 1-3 dagar Nega4vt BG utesluter invasiv savmpinfek4on Krävs dagliga analyser med svar inom 12-24 4m (det blir dyrt.) Inga data på pa4enter eoer bukkirurgi, anastomosläckage etc
Betaglukan Falskt neg: Pågående svampprofylax Cryptococcer/zygomyceter Non- invasive disease Falskt pos: Blod- och blodprodukbransfusion Betalaktam- an4bio4ka Kompresser (cellulosa) Bakteriella infek4oner Kontamina4on
Mannan + an4- mannan vid invasiv candidiasis Platelia ELISA. Cut off: mannan 0,5 ng/ml och an4- mannan 10 IU/ml Sens: 0,83 (0,79-0,87) Spec: 0,86 (0,82-0,90) Slutsats: B II För hepatosplenisk candidiasis B III Kan vara pos 6-7 dagar före blododlingar
Arabinitol i diagnos4ken av invasiv candidiasis
D- arabinitol (DA) och L- arabinitol (LA) är op4ska isomerer av en sockeralkohol (pen4tol) CH 2 OH CH 2 OH HOCH HCOH HCOH HCOH HOCH HOCH CH 2 OH CH 2 OH
D- arabinitol (DA) Metabolit från de flesta humanpatogena Candida spp. (ej C.krusei, C.glabrata) Påvisas i kroppsvätskor med GC eller GC- MS enzyma4sk analysis Serumkoncentra4onen ökar vid njursvikt (DA/ krea4nin kvot) DA/LA kvot i urin (och serum) oberoende av njursvikt. Normal kvot vuxna 2.0 +/- 0.6
Urin DA och LA kromatogram ökad kvot vs. normal kvot
Observa4ons studier Sensi4vitet i diagnos4k av invasiv candidiasis hos cancer pa4enter Kiehn (1979) 75% (15/20) Roboz (1990) 83% (10/12) Roboz (1992) 94% (15/16) Lehtonen (1996) 88% (15/17)
Barn med cancer och neutropeni Christensson et al. J Clin Microbiol 1997;35:636-40 Urin DA/LA kvot med GC- MS Prospek4v, blindad studie av 100 neutropena barn med cancer som monitorerades 2-3 ggr/ v. 10 invasiv candidiasis :100% (10/10) 23 empirisk svampbehandling :52% (12/23) 67 ingen svampbehandling :6% (4/67)
Invasiv candida Empirisk svampbeh. Ingen svampbeh. Kontroll
Tidigare diagnos med urin DA/LA Förhöjd urin DA/LA kvot före (median 8 dag) första posi4va blododling före (median 14 dag) start av empirisk behandling
Mors Upprepade nega4va blododlingar Posi4v blododling Ambisome
Fördelar med regelbunden monitorering av urin DA/LA kvot jämfört med upprepad blododling Tidigare diagnos Känsligare Korrelerar med behandlingseffekt Hos följande riskgrupper: Barn med cancer och neutropeni Vuxna med cancer och neutropeni Prematura barn
Urin DA/LA kvot har LÅG sensi4vitet vid Icke neutropena riskpa4enter (typisk IVA- pa4ent) (sensi4vitet 4/20 i Danmark) Postopera4v stor kirurgi med mul4pla drän Långvarig bredspektruman4bio4ka CVK- fungemi Candida oesophagit (HIV+) Kronisk (hepatosplenisk) candidiasis vid långvarig neutropeni
Normala urin DA/LA kvoter Kolonisa4on i urin med posi4v urinodling Oral candidiasis (HIV+)
Urin DA/LA i Lund Analyseras 5 dag/vecka Må- Fr Några få droppar urin luotorkas på filtrerpapper och skickas med vanlig post Svar samma dag Pris: 291 kr (Skåne), 417 kr (utanför Skåne)