Page 914 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 70: Fungal Infections 645

easily defined and the end points for success are clear-cut. Candidemia Several studies have shown that prompt treatment of candidemia signifi-
can be an isolated event, or it can be a herald for disseminated infection cantly decreases the mortality rate, and delay for as long as 48 hours after
involving multiple organs. Candidemia can culminate with sepsis, but the blood culture is performed is associated with increased mortality. 53,54
many patients, especially those with an indwelling central venous cath- Mortality appears to be higher in patients with candidemia due to C
eter, may be merely febrile with no localizing signs. Conversely, patients krusei, but this could reflect the fact that this species is seen more often
can have invasive candidiasis, but not be candidemic. in patients who have hematological malignancies. 27,33 Mortality associ-
■ INTRA-ABDOMINAL INFECTION ated with candidemia due to C parapsilosis is consistently lower than that
found with other species.
In some studies, mortality rates for patients
23,51
Intra-abdominal infections with Candida species most often occur sec- who have C glabrata fungemia have been noted to be higher than that
ondary to bowel perforation, anastomotic leaks after bowel surgery, and seen with C albicans, but in other studies, there was no difference or
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acute necrotizing pancreatitis. 40,41 Peritonitis and/or abscess formation the rates were lower. 23,29,55
can occur, and sepsis may ensue. C albicans is most often found, but
in some medical centers, C glabrata predominates. The symptoms of DIAGNOSIS
intra-abdominal infection due to Candida do not differ from those seen
with bacterial pathogens, and in fact, mixed bacterial-yeast infections The diagnosis of invasive candidiasis requires clinical suspicion that
are the rule. Candida infection could be present. The patient might be only mildly ill
The diagnosis is made when peritoneal fluid or abscess material or may have sepsis. Many of the manifestations of invasive candidiasis
obtained by ultrasound or CT-guided aspiration or at the time of sur- and candidemia do not differ from those seen with bacteremia and
gery yields Candida species. Growth of yeast from an indwelling drain other serious bacterial infections, and patients, especially those with an
is not adequate for the diagnosis of intra-abdominal Candida infection intra-abdominal process, can have polymicrobial infection with yeasts
because it usually reflects only colonization of the drain. and bacteria.
■ URINARY TRACT INFECTION ■ CLINICAL CLUES

Candiduria is common in the ICU; this is mostly related to the pres- Several findings can help point one toward a diagnosis of candidemia.
ence of indwelling bladder catheters and broad-spectrum antimicrobial Skin lesions can occur on any area of the body. The lesions are usually
agents. The vast majority of patients who are candiduric are colonized nontender, nonpruritic pustules on an erythematous base. They may be
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and do not develop upper tract infection or candidemia. In one large tiny, looking similar to folliculitis, with little erythema, or the erythema
prospective series in a general hospital setting, of 861 patients who had can extend for a centimeter around the lesion (Figs. 70-1 and 70-2).
candiduria, only 7 became candidemic. With obstruction, however, Biopsy of these lesions reveals budding yeasts and sometimes both yeast
43
pyelonephritis and subsequent fungemia can ensue. Further diagnostic and hyphal forms typical for Candida (Figs. 70-3 and 70-4).
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studies, such as ultrasound and/or a CT urogram, are often needed to Findings in the retina can also lead one to a diagnosis of candidemia
assess hydronephrosis and the presence of fungus balls. Several studies although most often the retinal findings are prompted by an ophthalmo-
44
have noted an increase in mortality in patients who are candiduric, but logical examination after blood cultures have yielded Candida species.
this is believed to be a marker for significant underlying illnesses and The major symptom is visual loss; however, patients in the ICU often
cannot be attributed to Candida urinary tract infection. 44,45 cannot complain of changes in visual acuity. Chorioretinitis appears as
■ RESPIRATORY TRACT INFECTION white spots on the retina that are distinctive enough to be considered
diagnostic when seen by an ophthalmologist (Fig. 70-5). Vitreal exten-
Pneumonia due to Candida species is rare. When pulmonary involve- sion of the infection causes worsening vision, and the ophthalmological
ment does occur, it is secondary to hematogenous spread in markedly examination reveals inflammatory changes in the vitreous and markedly
immunosuppressed patients. Infection is usually manifested as mul- abnormal visual acuity (Fig. 70-6). In patients in whom blood cultures
17
tiple nodules throughout the lung field; lobar infiltrates are uncommon. yield Candida, a retinal examination by an ophthalmologist is strongly
Sputum and bronchoalveolar lavage samples that yield Candida species
have low specificity, and lung biopsy is needed to establish the diagnosis.
In a prospective study of 232 ICU patients who died with pneumonia
and underwent autopsy, none of 77 patients with Candida species
isolated from a tracheal aspirate or bronchoalveolar lavage fluid had
histopathologic evidence of Candida pneumonia. As is true of candi-
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duria, respiratory tract colonization with Candida species is associated
with increased mortality in ICU patients, likely reflecting the severity of
underlying illnesses. 47

OUTCOMES OF INVASIVE CANDIDA INFECTIONS
Invasive candidiasis is associated with a high mortality rate. 3,22,23,48-52
Crude mortality rates as high as 71% have been reported. For many
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patients, invasive candidiasis is a marker for serious underlying illness,
but is not the cause of death. Attributable mortality has been difficult
to evaluate, and estimates have varied from 30% to 62%. A recent
3,49
prospective observational study in French ICUs found that independent
factors associated with mortality from invasive candidiasis included
diabetes mellitus, immunosuppression, and mechanical ventilation,
52
whereas a study that included all hospitalized patients in four medical
centers in Sao Paulo, Brazil, found the highest risk factors were advanced
age and high APACHE II score. The association of a high APACHE
51
II score and increased mortality in patients with candidemia has been
noted by others, as has increased mortality with increasing age. FIGURE 70-1. Rather inconspicuous pustular skin lesions in a patient with candidemia.
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