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Behavior of Aspergillus -characteristics

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0 Perché è Difficile Diagnosticare e Trattare l’Aspergillosi Invasiva?
Why is it so dificult to detect and treat invasive aspergillosis?

1 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what First of all it is worthwhile to confront you with the behavior of Aspergillus. Knowledge in this field will help you to understand the importance of this micro-organism for the world. Subsequently I will talk about the methods to detect the organism once it has entered the human body and how to treat an infection

2 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what Let’s have a look at Aspergillus

3 INFECTION! We easily speak of “having an infection”.....

4 INFECTION! .....without realizing that infections can be caused by pathogens that are very different in character. They range from prions that cause “mad cow disease” to parasites but.....

5 bacteria viruses fungi
.....the most familiar micro-organisms are bacteria, like staphylococci, viruses that may cause hepatitis and flu, and fungi.

6 EUKARYOTIC ORGANISM!! MRS. FUNGUS
cell membrane -ergosterol cell wall cholesterol Notably fungi are the subject of this conference. There are numerous different fungi, most of which are innocent or even eatable as mushrooms. It is remarkable that a fungal cell shows great similarity with a human cell. A female human cell, in particular, because it is perfectly eukaryotic with a pair of identical chromosomes; the fungal cell membrane consists of ergosterol, while the human cell contains cholesterol. In fact the only major difference is that the cell wall is absent in human cells. The similarity between a human and a fungal cell is one of the reasons why fungal infections are difficult to treat: drugs that are toxic to a fungal cell are also toxic to human cells!

7 “brush-shaped structure”
ASPERGILLUS 1729 FIRST DESCRIPTION “brush-shaped structure” MICHELI catholic priest Aspergillus is one of the most common fungi; it was described for the first time by an Italian priest, Micheli, who saw a striking similarity with the brush used in the church to sprinkle holy water

8 Aspergillus loves water to grow but can also easily survive in a tropical desert

9 ASPERGILLUS IS EVERYWHERE
environment By consequence, Aspergillus can be found everywhere. The most prominent location, however, is decaying bio-degradable material. Their main function, indeed, is to keep the world clean and to remove all dead organic material to prevent the world from becoming a big heap (cumulo) of dead biological materials. moss soil decaying material

10 According to Odds If we must believe medical reports in prominent journals, fungi nowadays have become a major threat for sick people. Let’s see whether this is true and, if it is indeed the case, how can the increasing danger be explained.

11 removes viruses, fungi and tumor cells
DEFENSE SYSTEMS Mucosa / Skin Granulocytes Commensal flora Humoral immunity T-cell function removes viruses, fungi and tumor cells antibody production micro-organisms in the gut against bacteria – pus formation The human body has several systems to protect it against organisms that may invade it and interfere with the function of the body and even with life. Each system has its own speciality. border control of our body

12 DEFENSE SYSTEMS T-cell function Humoral immunity Commensal flora
Mucosa / Skin Granulocytes Commensal flora Humoral immunity T-cell function Together they form an impressive defense wall. Of course disease and increasing age may eventually compromise its function, but the major danger CLIK is coming from medical interventions for serious diseases, with chemotherapy and therapeutical irradiation as the major demolishers. day

13 COURSE OF DEFENSE SYSTEMS
day Mucosa Granulocytes Commensal flora Humoral immunity T-cell function / Skin ASPERGILLUS INFECTIONS There are early and late effects of chemotherapy and radiation. CLIK The early damage mainly concerns our gastrointestinal lining (rivestimento) and the granulocytes, whereas late toxic effects hit the cellular immunity. Although, Aspergillus may be active in an early phase, it loves particularly the weakness of its most important opponent, the cellular immunity.

14 INFECTIOUS AGENTS IN RELATION TO THE COURSE OF DEFENSE SYSTEMS Garcia-Vidal et al. Clin Infect Dis 2008; 47: ASPERGILLUS So, most Aspergillus infections emerge late during the course of the disease and, typically, towards the end of life. time

15 BASIC RISK FACTORS FOR FUNGAL INFECTIONS
immuno- suppression epidemiologic exposure Aspergillus it is what we call “opportunistic pathogen”. These are pathogens that are not dangerous under normal circumstances but that may strike (colpire) when the defense is weakened while they are present. So, several factors have to coincide to open the gate for fungal infections. Adapted from RH Rubin, Boston

16 money shops OPPORTUNISTS!
This is of course a familiar situation that we often see in daily life; if you leave women alone with money in a shop, trouble is there. Money or shops alone are OK.

17 xxxxx Modern medical intervention have their price; with all our machines and drugs we keep the patient alive. This is impossible without interfering with the major defense systems. Infections are the rule (regola) and amongst them fungi, especially when the bacteria have been eradicated by antibiotics.

18 TRENDS INCIDENCE INVASIVE FUNGAL INFECTIONS Pagano et al
TRENDS INCIDENCE INVASIVE FUNGAL INFECTIONS Pagano et al. Haematologica 2006; 91: 80 70 ASPERGILLUS 60 50 number of cases 40 30 20 10 This explains why there is a steady (continua) increase of Aspergillus infections. There are many reports on this topic. The Italian study by Pagano from Roma is one of the most reliable reports. 87-88 92-93 97-98

19 9% mould-related deaths
INVASIVE FUNGAL DISEASE AFTER NON-MYELOABLATIVE ALLO-BMT Fukuda et al. Blood 2003; 102: 22% non-relapse mortality n = 163 39% mould-related 9% mould-related deaths Should we be concerned about Aspergillus infections? Well, let’s take an example on the impact: 163 patients neeed a bone marrow transplant. CLIK 22% will die in spite of the fact that the underlying diseases seemed to be cured and, of these 22%, CLIK 39% do die due to invasive fungal disease. So, in such a population, CLIK almost 10% will die of an invasive mould like Aspergillus.

20 MORTALITY OF INVASIVE ASPERGILLOSIS
Variation due to: timing of intervention timely diagnosis patients’ defense system treatment given The mortality depends on several independent factors. During this presentation I will discuss them.

21 MORTALITY OF INVASIVE ASPERGILLOSIS
97% 42% Variation due to: timing of intervention timely diagnosis patients’ defense system treatment given Early intervention after a timely diagnosis is extremely important. The difference in mortality may be more than 50% with 42% for early treatment and almost 100% for late. This is in fact true for all infections that are not self-limiting: early treatment gives a better prognosis.

22 1-2 cm per 24 hours GROWTH OF ASPERGILLUS
For fungal infections early intervention is crucial because Aspergillus can grow very rapidly, alike mushrooms in wet night during autumn.

23 MAKE YOUR CHOICE! Doctors are often surprised. Initially, they are confronted with abnormality of which the origin is obscure. When it becomes clear it may already have become very difficult to handle (maneggiare).

24 ONE WEEK LATER…. Within 5 days the infection may explode from considerable to enormous.

25 INFECTION -- DISEASE However, Rembrandt in 1632 already knew that in most cases the final diagnosis is only made at autopsy; unfortunately this picture is still valid in 2010.

26 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what The anti-aspergillus strategy is based on two pilars.

27 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what Diagnosis or detection and therapy.

28 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what Detection is an early phase proved to be one of the most prominent problem in the managemt of fungal disease.

29 WELCOME TO MYCOLOGY ASPERGILLUS spores hyphae spore
Let’s go back to Aspergilllus. This fungus grows from a spore via hyphal elements into multiple spores, CLIK like a fragmentation bomb or fireworks. Spore are spreaded into the air that we humans breath. ASPERGILLUS

30 ADMISSION TO THE HUMAN BODY
Aspergillus is clearly mainly an airborne infection, the spores in the air will enter the body through the airways and they will arrive CLIK in nasal sinuses and bronchi where the first lesions are usually found. Knowledge of its behavior may help us to detect the imposter. Clinical symptoms do provide, although aspecific, clues to help further investigations. If a patients starts to cough it is logic to perform a chest X-ray.

31 Caso MK - 5 The chest X-ray may shows an evident infiltrate in a lung; such an infiltrate can be caused by many micro-organisms and even malignant growth and, therefore, additional investigations are required to ascertain the diagnosis.

32 EVOLUTION OF AN INFECTION AND MORTALITY
TRADITIONAL DIAGNOSIS 97% 42% The traditional diagnostical procedures are very time consuming; therefore (quindi), the mortality will be almost 100% when a final diagnosis is made because during the procedures the fungus does not stop expanding. FUNGAL BURDEN

33 97% 42% AWAY FROM EMPIRISM? TRADITIONAL DIAGNOSIS NEW TOOLS
diagnostics NEW TOOLS Modern techniques, like CT scanning and antigen testing, make it possible to establish the diagnosis in a much earlier stage, which enhances the chances for a cure. FUNGAL BURDEN

34 FIRST TEST POSITIVE FOR ASPERGILLOSIS IN HEMATOLOGICAL MALIGNANCIES Florent et al. J Infect Dis 2006;193: serology CT culture histology More than 10 days can be gained; whereas in the past clinician needed more than to weeks to arrive at the final diagnosis after the first suspicion, CLIK nowadays the diagnosis can be reasonably solid within a week or even within 2-3 days. DAYS 55 patients

35 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what The other principle of management lies in the selection treatment itself.

36 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what When it comes to treatment, the clinician has to decide when to start therapy and what to treat with.

37 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what About when: it is clear to everybody that starting therapy as early as possible gives a favorable prognosis. This basic principle provided an enormous boost (impulso) to the popularity of empirical antifungal therapy, that means to start the treatment before the diagnosis has been made.

38 ADMINISTRATION OF ANTIMICROBIALS IN RELATION TO THE COURSE OF NEUTROPENIA
100% 75% 50% antibacterials Empirical anti- fungals >1000 Briefly, this implied that immunocompromised patients, who remained febrile in spite of treatment with broad-spectrum antibiotics, CLIK were given antifungal drugs assuming that the fever might be due to a fungal infection. 1000 GRANULOCYTES 500 <100 days

39 ESTIMATING TIME FOR INTERVENTION
Peter Donnelly & Ben dePauw ESTIMATING TIME FOR INTERVENTION Aspergillus infiltrate antigen Persisting fever + very high risk or a suggestive symptom a suspected sign any positive test When the fungal burden increases, the symptoms evolve and become more clear. From fever only to fever with a cough or chest pain, and a circulating antigen to a classic pulmonary infiltrate. So when should antifungals be started? If one starts too early (persisting fever alone) many patients are overtreated and if one starts too late, many patients will die. The conclusion is simple: in between. In practice, this implies that a patient should have a second sign or symptom next to fever like a typical abnormality on the chest CT or the presence of aspergillus-related antigens in the blood, before antifungal should be commenced. day // > 42

40 TACTICS ITALIAN: -strong defense -efficient attack BRAZILIAN:
-no defense -intuitive attack Apart from these contemplations, we must realize that there are many ways that can lead us to Rome. Some strategies, however, are more attractive than others.

41 Behavior of Aspergillus -characteristics
TOPICS Behavior of Aspergillus -characteristics Principles of management -detection -treatment when and what When the issue ‘when’ has been settled, it is time to turn to what.

42 PACE OF DEVELOPMENT OF NEW ANTIFUNGAL AGENTS
isavuconazole caspofungin anidulafungin micafungin voriconazole posaconazole PACE OF DEVELOPMENT OF NEW ANTIFUNGAL AGENTS 1960 1970 1980 1990 2000 Adapted from Rex & Edwards, 1997 AmBisome fluconazole Amphocil Abelcet itraconazole ketoconazole miconazole 5-flucytosine terbinafine Amphotericin B Nystatin Griseofulvin CLIK Over the last two decades the production of antifungal compounds has shown an explosive growth, similar to the growth of Aspergillus itself. 1950

43 EORTC IFICG RESULTS FIRST LINE TREATMENT OF INVASIVE ASPERGILLOSIS Herbrecht et al N Engl J Med 2002; 347: Cornely et al. Clin Infect Dis 2007; 44: Viscoli et al. J Chemother 2007; 19, suppl 5:36 10 20 30 40 50 60 % response 76/144 (53%) 42/133 (32%) 53/107 (50%) 25/51 (49%) The historical response rate for the ‘golden standard’ amphotericin B lies around 30%; in a direct comparative trial voriconazole, the leading azole, proved almost twice as effective. In a less solid trial CLIK liposomal amphotericin B produced promising results as well, but it was never directly compared to another antifungal compound in a therapeutic setting. CLIK This is also true for caspofungin. Data on the efficacy of other candin are not available. Ampho B Voriconazole Lipo-AmB Caspofungin

44 OUTCOME OF ASPERGILLOSIS IN RELATION TO INITIAL ANTIFUNGAL THERAPY Nivoix, Y et al. Clin Infect Dis 2008; 47: n = 289 S U R V I V A L n = 62 n = 51 n = 127 70% P=0.016 47% Therefore, it is prudent to see what the compounds have to offer in daily clinical practice. In a French survey the results appear to be remarkably similar to those obtained in trial with a superior survival for patients treated with voriconazole

45 OUTCOME OF THERAPY FOR ASPERGILLOSIS ARISING DURING AML IN DAILY PRACTICE Pagano et al. SEIFEM 2008
140 cases First line therapy 40 30 20 10 28% 27% 21% 16% N° of patients treated An Italian study arrived at the same conclusion, confirming the French data and the trial results. voriconazole L-AmB caspofungin combo 45

46 Aspergillosis attributable mortality
OUTCOME OF THERAPY FOR ASPERGILLOSIS ARISING DURING AML IN DAILY PRACTICE Pagano et al. SEIFEM 2008 140 cases Aspergillosis attributable mortality 40 30 20 10 N° of patients treated 18% 24% 32% 23% This Italian study provided additional information: using two drugs in combination did not improve the outcome. It is remarkable that independent of the antifungal therapy given, a 100% cure rate is never reached and this reflect the fact that the natural immune system is required to control an invasive fungus completely. voriconazole L-AmB caspofungin combo 46

47 low dose corticosteroids
CORTICOSTEROIDS AND SURVIVAL OF ASPERGILLOSIS IN HSCT Cordonnier et al. Clin Infect Dis 2006;42: 51 patients with aspergillosis 41 allo HSCT 10 auto S U R V I A L low dose corticosteroids high dose The reason is that a recovery of the immune system is required to achieve an optimal response rate; for instance if a high dose of corticosteroids is maintained during treatment of an invasive aspergillosis, the response rate drops below 20%!

48 RELATION OUTCOME OF FUNGAL INFECTIONS AND GRANULOCYTE COUNT
DECREASING GRANULOCYTES Response 36% INCREASING GRANULOCYTES Response 86% Moreover, the response of the infection to antifungals is very high when the granulocytes are returning after chemotherapy in contrast to the situation where the number of leukocytes in the circulation is decreasing.

49 RELATION OUTCOME OF FUNGAL INFECTIONS AND STATE OF UNDERLYING DISEASE
SUCCESSFUL OUTCOME REMISSION 61% REFRACTORY UNDERLYING DISEASE 8% n = 63 If the underlying disease is not controlled, the condition of the body becomes too weak to defend itself against intruders – CLIK it is obviously much easier to control aspergillosis in a healthy body with a properly working defense system.

50 attributable mortality
EVOLUTION OF ASPERGILLUS INFECTIONS AMONGST PATIENTS WITH ACUTE LEUKEMIA Pagano et al. Clin Infect Dis 2007; 44: new anti- fungals 3 6 9 12 15 2006 Incidence (%) attributable mortality 60% 50% 40% 30% 20% 10% serological tests CT-scan Over the last 20 years the incidence of patients with an invasive aspergillosis has increased but CLIK the prognosis has improved. It is tempting to assume that the improved prognosis is due to the new antifungal drugs CLIK but better diagnostic tools CLIK, undoubtedly, had at least a comparable impact.

51 CRUCIAL ELEMENTS IN AVOIDANCE OF DISASTERS
Knowledge on behavior of the offender High awareness Early recognition Early treatment I hope that I made it clear that for optimal treatment you have to know your enemy and that you have to be vigilant all the time, to be able to detect the infection in an early phase and to start treatment timely. Just like the policeman in the picture: he recognizes a very dangerous traffic situation. You see it yourself – the girl is not wearing a helmet and that is compulsory.

52 CONCLUSIONS ASPERGILLUS IS EVERYWHERE ***** IT IS AN OPPORTUNIST
EARLY DIAGNOSIS REQUIRES CONTINUOUS, SPECIFIC SCREENING ANTIFUNGALS MAY KEEP A PATIENT ALIVE but CURE NEEDS RECOVERY OF THE IMMUNE SYSTEM The conclusions are simple, Aspergillus can not be avoided; a clinician has to stay alert all the time and antifungals do help but the battle will be lost if there is no recovery of the condition of the patient. All this is true. If I had lied, my nose would have grown

53 Buona conferenza a tutti voi! Grazie, Ben!


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