invasive fungal infections are a major problem in the neonatal intensive care unit ( nicu ) .
candida species are as the fourth most common cause of late - onset infections in the neonatal intensive care unit ( nicu ) and are responsible for considerable morbidity and mortality .
about 12% of all neonatal infections are due to candida species [ 24 ] ; cases increased 10-fold between 1981 and 1995 [ 5 , 6 ] .
reported mortality rates for infants with invasive neonatal candidiasis are between 25 and 50% , compared to an overall mortality of 4.7% for all nicu admissions .
major risk factors associated with invasive neonatal candidiasis include extreme prematurity , prolonged central venous catheterization , and prolonged use of broad - spectrum antibacterial agents [ 712 ] .  
blood cultures are still considered as the gold standard for the diagnosis of invasive neonatal candidiasis . however , when compared with bacterial pathogens , their sensitivity is less than ideal . in a large report of autopsy - proven invasive candidiasis , the majority of cases lacked a positive blood culture . in a cohort of 41 patients with hematologic malignancies and autopsy - proven candidiasis , 28% of those who had single - organ involvement had a previous positive blood culture . when at least 3 organs were found to be infected in postmortem examination ,
the blood volumes necessary to optimize organism recovery are not easily attainable in neonates [ 15 , 16 ] .
therefore , relying solely in blood cultures could underestimate the true incidence of invasive neonatal candidiasis .
the absence of a fungal pathogen isolated in a blood culture may lead to underdiagnosis of invasive neonatal candidiasis , and in turn , to a delay in treatment institution , which could contribute to the high mortality observed in previous studies [ 1 , 2 , 9 ] .  
we assessed for the effect of delayed recognition and treatment of invasive neonatal candidiasis and for risk factors associated with mortality in a tertiary care nicu over the five - year period before the institution of routine fluconazole prophylaxis in our nicu .
we conducted a retrospective cohort study of all cases of culture - proven invasive neonatal candidiasis admitted to the nicu at the ucla medical center between january 1 , 1998 and december 31 , 2002 .
study participants were identified from microbiology records of all infants admitted to the nicu with a positive fungal culture .
cases of invasive neonatal candidiasis were defined as those that fulfilled the following criteria ( 1 ) + ( 2a ) or ( 1 ) + ( 2b ) : a clinical picture compatible with fungal sepsis , defined by patients meeting at least 5 criteria : admission to an nicu with high rate of candidemia , history of broad - spectrum antibiotic coverage , use of a third - generation cephalosporin   negative bacterial blood culture results , a falling platelet count , use of systemic steroids , npo , need for mechanical ventilation , and cardiovascular instability requiring pressor support ; a fungal pathogen isolated from blood culture either from a line or peripheral site , urine by bladder catheterization , peritoneal fluid by paracentesis , pleural fluid by pleurocentesis ; when the only fungal isolate came from a deep aspirate from an endotracheal tube , patients had to fulfill clinical criteria for sepsis and all 4 of the following clinical criteria for pneumonia ( radiographic changes , need for increase in mechanical ventilation , increase in tracheal secretions , abnormal peripheral white blood cell count and/or bandemia ) . 
					
the analysis was conducted comparing survivors with nonsurvivors . in cases of multiple fungal infections in a single patient , data was analyzed from the final episode in order to evaluate the primary outcome .
survival was defined as either discharge to home or transfer to a lower level of care .
medical records were reviewed , and information was obtained on gender , birth weight , gestational age , underlying illness , hospital course , invasive procedures , outcome , use of anti - infective agents , and bacterial infections .
data are presented descriptively for demographics , culture location and species of fungus responsible for infection .
student 's t - test was used to compare single variable differences between mortality and survival to discharge groups .
between january 1 , 1998 and december 31 , 2002 , there were 1686 admissions to the ucla nicu .
, 63 patients met our definition for invasive neonatal candidiasis , for a prevalence of 37 cases/1000 admissions .
the mean gestational age ( ga ) of both the infants who expired and survived invasive neonatal candidiasis was 30 weeks ( range : 2340 weeks ) . mean birth weight ( bw ) was 1628 grams ( range : 4094470 ) in patients who expired and 1741 grams ( range 4863800 ) in survivors .
in the survivor group , 10 patients ( 24% ) had ga between 23 and 25 weeks and 13 patients ( 32% ) had ga of 2634 weeks , compared with 7 ( 31% ) and 4 ( 18% ) , respectively , in the mortality group .
10 survivors ( 24% ) had congenital heart disease , compared with 5 ( 23% ) infants in the mortality group . 3 survivors ( 7% ) had other major congenital anomalies , compared with 3 nonsurvivors ( 14% ) .
5 survivors ( 12% ) and 3 nonsurvivors ( 14% ) were diagnosed with chromosomal anomalies .
a previous , culture - proven bacterial infection was identified in 27 survivors ( 66% ) and 18 nonsurvivors ( 82% ) ( p = 0.25 )
both groups differed significantly in mean number of positive fungal cultures , days with central venous catheters , mean platelet count nadir , days in nicu before invasive fungal infection , days on ventilator ( both total and prior to fungal infection ) , previous use of a third - generation cephalosporin , and days of treatment with intravenous antibacterial agents prior to fungal infections .
mean duration of positive cultures , ga , birth weight , total icu days , and days of antifungal therapy were comparable between those infants who expired and those who survived until discharge .  
the most common isolates identified were candida albicans ( 57% ) and candida parapsilosis ( 27% ) , followed by candida tropicalis ( 5% ) , candida lusitaniae ( 3% ) , candida glabrata ( 2% ) , and malassezia furfur ( 2% ) .
we did not find an association between fungal species and outcome of invasive fungal infections .
we did not observe a significant difference in culture sites between the survivor and mortality groups ( table 3 ) .
multivariate analysis demonstrated a higher risk of mortality with increasing number of positive fungal cultures as well as the number of days of antibiotic use prior to the fungal infection ( p = 0.005 and 0.009 , resp . ) .
our population included 23 patient with blood isolates ; of these , 15 had the cvc removed after the positive blood culture , 11/15 ( 73% ) survived .
3 of 8 ( 38% ) patients in which the cvc was not removed survived ( p = 0.09 ) . thirty - three patients had further diagnostic studies performed ( head / cardiac / renal / abdominal ultrasound or ophthalmologic exam ) . of these , 8 ( 24% ) had evidence of invasive fungal disease .
of the 8 infants with end - organ evidence of fungal disease , 3 had only blood cultures positive and 5 had positive fungal cultures at multiple sites .
in contrast , 6/25 ( 24% ) patients who had no end - organ evidence of fungal disease expired ( p < 0.01 ) . of these ,
9 patients had multiple positive sites ; in 7 the only source was urine , in 4 peritoneal fluid , 3 had only positive blood cultures , and 2 only tracheal cultures .
5 of these 7 had autopsy evidence of invasive fungal disease and a positive postmortem culture .
they were 25- and 26-week premature infants , respectively , and each had treatment started 4 days after the first positive culture .
the second patient had negative renal and abdominal ultrasounds obtained after peritoneal fluid yielded candida parapsilosis .
the third patient was a full - term infant with congenital heart disease who had autopsy evidence of candida sepsis , with involvement of the heart , liver , and kidneys .
this patient had many negative blood and urine fungal cultures ; the only positive culture isolated came from a tracheal aspirate which was positive for candida lusitaniae .
microabscesses were identified in postmortem examination of the peritoneal cavity ; however , postmortem cultures were negative .
one had candida parapsilosis in tracheal aspirates , and the other had had candida parapsilosis in tracheal aspirates and urine .   
median time to initiation of treatment after the first positive fungal culture was obtained was 4 days in the mortality group and 2 days in the survivor group ( p = 0.004 ) .
when we analyzed the relationship between mortality and the interval from the day the first positive culture was drawn and the day that antifungal therapy was started , we found mortality rates of 22.5% ( 7/30 ) , 40% ( 6/15 ) , and 54% ( 7/13 ) when those intervals were 02 days , 27 days , and > 7 days , respectively .
each 24-hour delay in the initiation of antifungal therapy was associated with a 10.9% increase in odds of mortality ( or 1.109 , 95% ci : 1.0031.226 ) .
when we exclude patients in which the only positive culture was obtained by tracheal aspirate , median times to treatment initiation are 4 days for the mortality group and 1 day for survivors ( p = 0.02 ) .
time from culture to treatment was similar in patients without a blood fungal isolate and fungemic patients .
similarly , we did not observe a significant difference in the distribution of culture sites in those patients in which therapy was delayed over 48 hours when compared with those infants who received antifungals earlier .
fifty - eight of 63 patients ( 92% ) received systemic antifungal therapy with either amphotericin b deoxycholate or amphotericin b lipid complex .
of the 5 patients who did not receive therapy , 3 survived , and two expired .
their ga ranged from 25 to 40 weeks , and the diagnoses were as follows : chromosomal anomalies in one baby , prematurity in two infants , congenital heart disease in one patient , and noncardiac congenital anomalies in one subject .
the source of isolates in the patients who expired was tracheal only in one patient and urine plus tracheal aspirate in one infant . in survivors , isolates came from peritoneal fluid in two infants and urine in one patient .
we believe that the observation of increased mortality in patients where a longer interval ensued between obtaining cultures and stating antifungal therapy is important .
although certainly not surprising , an association between delay in initiation of antifungal therapy and mortality has not been documented previously in the literature . in severe infections , one can expect a more favorable outcome when therapy is promptly instituted .
however , there is an inherent delay between the clinical presentation of sepsis , when cultures are presumably obtained , and the availability of results .
a study by schelonka and moser   suggested that candidemia can be detected within 72 hours . a septic - appearing newborn routinely receives antibacterial agents at the time of clinical presentation .
in contrast , many clinicians will only start antifungal therapy when a positive culture is reported or when the patient fails to improve after a period of antibacterial agents . in a retrospective study , makhoul et al .  
this was attributed to a policy of starting empiric antifungal therapy immediately after obtaining cultures in neonates with risk factors for fungal sepsis , instead of waiting for culture results .
et al .   evaluated data from a multicenter cohort to develop a model to provide guidance to neonatologists as to when to consider empirical antifungal therapy .  
we did not identify an association between culture site and therapy delay , which could potentially result in a clinician bias against nonblood isolates .
patients in whom the only source for the fungal pathogen was a tracheal culture had a similar outcome to the remainder of the study population .
tracheal cultures are interpreted by many clinicians with skepticism , due to a concern about a perceived poor correlation between tracheal isolate and lower respiratory tract pathogens .
several studies have found correlation between isolation of candida in tracheal cultures and its presence in lung parenchyma or the subsequent risk of candidemia in neonates [ 2022 ] . in a septic - appearing newborn with findings of clinical pneumonia ,
when a bacterial pathogen is not found , or when empiric antibacterial therapy fails to create a clinical response , one may consider that the presence of a fungal isolate in a tracheal aspirate should be considered a true pathogen , and specific therapy should be instituted .  
the patients who died had onset of infection at a mean of 69 days versus 33 days in the survivors .
this conflicts with data presented previously from a review of a private practice database , which reported that a younger age at the time of infection is associated with mortality .
this could be due to the inherent selection bias in patient complexity observed in large , tertiary referral institutions , when compared with community - based practices .  
although candida albicans was the most common isolate recovered , our data confirm the emergence of non - albicans species as major causes of invasive neonatal candidiasis [ 1 , 2 ] .
we did not find a correlation between fungal species and mortality . in a study of 45 cases of neonatal candidiasis over a 10-year period ,
faix   reported that 7 of 29 infants with candida albicans died , compared to no deaths in 16 infants with candida parapsilosis .
the relatively large number of candida parapsilosis found in newborns could be due to the known propensity of candida parapsilosis to adhere to foreign material [ 17 , 24 , 25 ] .
it has been suggested that the high prevalence of candida parapsilosis reflects the aggressive use of intravascular devices in nicus .
there is evidence that candida parapsilosis is commonly carried on the hands of health care workers .
transmission from infected mothers is unlikely to account for the unusual prevalence of this organism in neonates , since candida parapsilosis is rarely seen on vaginal cultures , whereas candida glabrata , a common vaginal isolate , is an uncommon cause of candidemia in infants and children [ 26 , 27 ] .
other species , such as candida lusitaniae and candida tropicalis , were uncommon in our study population , as observed by others .
the previous use of a third - generation cephalosporin antibiotic was associated with mortality in our study population . in our study population
, these agents ( cefotaxime and ceftazidime ) were used empirically in virtually all cases .
third - generation cephalosporins have been previously identified as risk factors for acquisition of an invasive fungal pathogen [ 6 , 10 , 11 , 17 ] .
the number of positive fungal cultures , time in the nicu , and total time of mechanical ventilation were all increased in nonsurvivors .
the relationship between multiple positive cultures and outcome has been reported previously [ 29 , 30 ] .
several other studies have illustrated the link between duration of intubation and length of nicu hospitalization with emergence of fungal sepsis [ 8 , 9 , 31 ] .   
the presence of suggestive imaging studies and multiple positive fungal cultures were predictive of mortality in infants with fungal sepsis in our population .
end - organ involvement and multiple positive cultures have been shown to be markers for treatment failure and predictors of disease severity [ 29 , 31 ] .
our study had the unique feature of an unusually high rate of autopsies performed , which confirmed the presence of gross pathology findings of invasive fungal disease in 5 neonates , including ischemic fungal colitis in 2 patients , peritoneal microabscesses in one patient , renal mycetomas in one neonate , and multiple organ involvement in one infant .     
these data have the limitations inherent to a single - center , retrospective study , therefore we were unable to answer questions about the reasons for delay in initiation of antifungal therapy .
however , given the degree of difficulty in the diagnosis of neonatal candidiasis , its increasing incidence , and the delay of fungal cultures , we believe that a risk - factor - based approach to empirical treatment could be justified in a sick appearing newborn .
 
 objective / methods . 
 to determine the outcomes of invasive neonatal candidiasis before institution of routine antifungal prophylaxis , we conducted a retrospective review of cases of invasive candidiasis in newborns in a referral - based neonatal intensive care unit located in a single tertiary academic center between january 1998 and december 2002 . 
 
 results . 
 sixty - three newborns with invasive neonatal candidiasis were identified . 
 overall mortality rate was 35% . 
 virtually every infant had a central venous catheter ( cvc ) , required mechanical ventilation and previous administration of antibacterial agents . 
 delayed institution of antifungal therapy was associated with increased mortality . in addition , 
 length of hospitalization , duration of prior antibacterial therapy , mechanical ventilation , and cvc use , as well as evidence of end - organ disease , were associated with an adverse outcome . 
 conclusions . 
 reliance on available laboratory tools in cases of invasive neonatal candidiasis can result in delayed diagnosis and increased mortality . 
 a risk - factor - based approach to empirical treatment could be justified in this setting . 
 
1. Introduction
2. Materials and Methods
3. Results
4. Discussion