HOUSTON - The use of topical petrolatum ointment for skin care in the extremely low birthweight infant might be associated with an increase in the incidence of systemic candidiasis.
"Therapies to protect the immature skin barrier of extremely low birthweight infants should be evaluated for infection risk potential before their implementation," said Judith R. Campbell, MD, who is from Baylor College of Medicine, here.
"Candida sp. are a frequent cause of late-onset sepsis as defined as occurring at greater than 7 days of age as nosocomial infections in prematurely born neonates," she said. "The incidence of Candida sp. infection in very low birthweight infants, less than 1,500 g, is estimated to be between 1.5% and 5%. In extremely low birthweight infants, those who weigh less than 1,000 g, the estimated incidence is higher."
The reported risk factors for systemic candidiasis in neonates include prematurity, prolonged hospitalization, broad-spectrum antibiotic use, prolonged endotracheal intubation, total parenteral nutrition, steroids and insulin therapy for hyperglycemia.
"Extremely low birthweight infants have an ineffective epidermal barrier, as the stratum corneum does not become functionally mature until 32 to 34 weeks of gestation. Transepidermal water loss may result in fluid and electrolyte imbalance as well as thermal instability," Campbell said.
The use of topical petrolatum ointment has been proposed as a method to reduce transepidermal water loss and improve skin condition. In a 48-bed neonatal intensive care unit in Houston, the incidence of systemic candidiasis in infants who weighed less than 1,500 g rose from 5.9% in 1997 to 17.4% in the first quarter of 1998.
"This increase was temporarily associated with a change in skin care for extremely low birthweight infants in December of 1997," she said.
Therefore, Campbell and her colleagues conducted a case-control study to determine whether the use of topical petrolatum ointment was related to the increase in cases of systemic candidiasis in extremely low birthweight infants. The study was conducted between Dec. 1, 1997 and July 31, 1998.
Cases were defined as infants who weighed less than or equal to 1,000 g with Candida isolated from blood, cerebrospinal fluid and urine collected by bladder aspiration or catheterization. "Three controls were selected for each case, and the controls were matched by date of birth during the study interval and by birthweight category, either less than 750 g or 751 to 1,000 g. Controls were accepted only if they survived to at least the age of diagnosis of the matched case," she explained.
The medical records for cases and controls were reviewed, and data were recorded on a standardized form. Ten cases, with a mean age of onset of 21 days, were identified.
"Each case had fungemia; the other culture-positive sites were the peritoneal fluid in three, urine in three, cerebrospinal fluid in two and bone or joint fluid in two. Three different Candida sp. were identified: six infants had C. albicans three had C. parapsilosis and one had C. lusitaniae," she added.
The mean birthweight of the cases was 716 g, and the mean gestational age was 24.8 weeks, which was similar to the mean birthweight and the mean gestational age of the control group, but this difference did not reach statistical significance.
"There were eight boys in the case group, but only 12 of 30 in the control group. However, this did not reach statistical significance. The cases were more likely to have been delivered vaginally: six of 10 patients as compared to seven of the 30 controls. We evaluated the duration of exposure to several therapies. Steroids, usually dexamethasone, were administered for a mean of 2.8 days in the case group and 3.3 days in the control group. The mean duration of antibiotic therapy for cases was 17.1 days, and the mean duration of antibiotic therapy for controls was 13.7 days. However, this difference was not statistically significant," she said.
Days of insulin therapy for hyperglycemia and days of total parenteral nutrition were similar in both groups. Cases required endotracheal intubation for a mean of 13.7 days, as compared to 8.7 days for the control group.
Eight of the 10 cases had received topical petrolatum ointment. Of the 30 controls, 22 had not received topical petrolatum therapy. The infants with systemic candidiasis were 11 times likely to have received topical petrolatum therapy as compared with the control group.
After topical petrolatum ointment therapy was discontinued and adherence to infection control policies was emphasized through inservice education, the incidence of systemic candidiasis decreased to less than 2%, and all cases survived.
Genetic analysis of the 10 Candida isolates was performed in the laboratory at the University of Texas Health Science Center in San Antonio. The analysis suggested that the most cases were due to different strains of Candida but it was possible that horizontal transmission occurred in the three infants who had C. parapsilosis infection.
"We speculate that topical petrolatum ointment promoted Candida overgrowth at skin and mucosal surfaces and was a contributing factor to systemic candidiasis in these infants," Campbell said. Further studies on the potential infectious risks of this therapy are warranted.
For more information:
- Campbell JF, Zaccaria E, Baker CJ. Systemic candidiasis (SC) in extremely low birth weight (ELBW) neonates: topical petrolatum ointment (TPO) as a risk factor. Presented at the 36th Annual Meeting of the Infectious Diseases Society of America. Nov. 12-15, 1998. Denver.
Editor's note: Someone needs to look at diaper rash. - P. Brunell, MD
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