Discussione e conclusion

Il seguente lavoro ha avuto lo scopo di valutare un approccio diagnostico rapido per le malattie respiratorie nel puledro e quindi fare una diagnosi precoce in modo da intervenire tempestivamente con un’adeguata terapia. In tal senso è stata presa in considerazione l’ecografia pleurica per identificare l’eventuale presenza di ascessi polmonari in soggetti che presentavano sintomatologia respiratoria.

L'utilizzo dell'esame ecografico pleurico come mezzo diagnostico di screening per discernere soggetti con formazioni compatibili con ascessi dai soggetti con altri tipi di lesione, quali ispessimento pleurico (comet tails), consolidamenti polmonari, atelettasia polmonare, etc. è risultato molto utile nel nostro lavoro. Questo risultato è in accorto con quanto già riportato da altri autori che ipotizzano l'utilizzo dell'ecografia come indagine collaterale da eseguire nella fase iniziale dell'iter diagnostico (Ramirez et al., 2004). L'esame ultrasonografico, oltre a risultare utile nella procedura diagnostica delle patologie respiratorie del puledro, è anche un esame semplice da eseguire, non invasivo e con visualizzazione immediata della lesione. Tale evidenza non risulta però sufficiente a valutare il quadro eziopatogenetico dell’ascesso al fine di impostare un protocollo terapeutico, essendo adatta unicamente a definire localizzazione, numero, morfologia, complessità ed entità della lesione.

L’iter diagnostico di una lesione ascessuale dovrà, pertanto, proseguire con l’identificazione dell’agente patogeno, discriminandone la tipologia (fisico, chimico, biologico), e la sensibilità terapeutica.

Una volta individuati i soggetti con alterazioni polmonari (ascessi, consolidamenti, etc) la procedura diagnostica considerata il gold standard

per la raccolta di campioni utili ai fini della diagnosi eziologica è il lavaggio broncoalveolare. Lo svantaggio di questa metodica è la sua invasività, anche se minima, comunque talvolta mal tollerata dal proprietario più che dal puledro.

Mediante il lavaggio broncoalveolare è possibile raccogliere materiale direttamente dalle vie respiratorie profonde.

Sul liquido refluo verrà eseguito un esame citologico che nel nostro studio ha permesso di distinguere la flogosi causata da R. equi rispetto alle altre specie batteriche. Infatti, dal nostro studio si evince che nei soggetti risultati poi positivi a R. equi, il numero totale di cellule/µl (1457,1±946,6 vs 477,2±173,7) e la percentuale dei neutrofili (45±17,8% vs 19,8±10,6%) risultano statisticamente più elevati rispetto ai soggetti affetti da polmonite causata da altri batteri, mentre la percentuale dei linfociti è inferiore (6,8±3,2% vs 14,9±6,9%). In bibliografia non esistono lavori simili al nostro con cui poter confrontare i dati raccolti.

A confermare l'ipotesi diagnostica emessa con la citologia, il liquido refluo è stato utilizzato per eseguire una coltura batterica. Se le caratteristiche macroscopiche delle colonie isolate erano compatibili con Rhodococcus

equi, veniva eseguita una PCR per avere la diagnosi eziologica certa e per

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Ringraziamenti

Nello svolgere questo lavoro è stata di fondamentale importanza la collaborazione del Prof. Vincenzo Cuteri, della Prof.ssa Annamaria Attili e della Dott.ssa Silvia Preziuso per quanto riguarda le indagini batteriologiche e bio-molecolari, e della Dott.ssa Paola Marmorini per la raccolta dei campioni in campo. A loro vanno i miei più sentiti ringraziamenti.

Ringrazio inoltre la Dott.ssa Micaela Sgorbini e il Prof. Michele Corazza per la loro estrema disponibilità e la fiducia che hanno sempre dimostrato nei miei confronti e che mi hanno accompagnato fino a questo traguardo. Infine, ma non per ultimi, ringrazio i miei genitori per avermi sostenuto lungo questo cammino non soltanto economicamente.