Neoatal candidiasis

ABSTRACT

Invasive candidiasis has become a significant problem of preterm, low birth weight infants. Candida albicans is the most frequent cause, but other species of Candida, such as C. parapsilosis, C. tropicalis and C. glabrata are being increasingly reported. Early acquisition of the Candida sp. occurs from the mother's genital tract during delivery, while colonization thereafter is acquired mostly through caretakers. The major risk factors are low birth weight, prolonged use of central venous catheter or other lines, hyperalimentation therapy, prolonged use of broad spectrum antibiotics, and an extended period of endotracheal intubation. Colonization of skin or gut with Candida species may precede bloodstream infection, and this could be facilitated by slight trauma to fragile integument. The clinical features of neonatal candidiasis are non-specific and include deteriorating respiratory function, abdominal distention, and temperature instability. An apparently septic preterm neonate who deteriorates, despite adequate antibiotic treatment, should be considered to have systemic candidiasis, particularly if other risk factors are present. In the disseminated disease, meningitis, skin lesions, endophthalmitis or involvement of renal/genitourinary tract are not uncommon. Affected neonates may exhibit neutropenia or neutrophilia, thrombocytopenia, glucose intolerance and oliguria. At present, no single laboratory test can reliably diagnose systemic candidiasis. Blood cultures, preferably by lysis centrifugation method, microscopic examination of buffy coat smears, culture and microscopic examinations of urine samples collected by suprapubic aspiration, serial measurements of C-reactive protein, and the determination of Candida antigen levels may provide useful diagnostic information. Fundoscopic examination of the retina for fluffy white lesions, and ultrasound scans for cardiac, hepato-splenic and renal involvement, should be routinely performed. Once candidiasis is diagnosed, treatment should be started promptly. The removal of central lines and stoppage of broad-spectrum antibiotics are initial important steps and should be considered. Amphotericin B remains the drug of choice. Nephrotoxicity is minimal if the dose is kept under 1 mg/kg in preterm infants. Although amphotericin B can be used alone, combination with flucytosine [100 mg/kg] may be needed to treat neonates with severe central nervous system involvement. The duration of antifungal therapy depends upon the severity of infection and response to therapy, and therefore must be individualized. In absence of any consensus on the duration of therapy, it should be continued for 7-14 days after the first negative blood culture and/or when the signs or symptoms of the disease have completely disappeared. Fluconazole has been used successfully in some studies with minimal side-effects. A dose of 6 mg/kg every three days in the first week of life, followed by 6 mg/kg every two days in subsequent weeks, has been suggested. Likewise, liposomal amphotericin B has been successfully used in a few studies with a dose of 3 mg/kg in most of the cases. Despite sporadic reports of the therapeutic efficacy and safety of both these drugs, additional evaluation is needed to develop a consensus administration protocol. Until such information is available, fluconazole and liposomal amphotericin B may be used selectively in neonates who are either unable to tolerate conventional amphotericin B or who have failed the treatment by it