ERG11 Gene Mutations and MDR1 Upregulation Confer Pan-Azole Resistance in Candida tropicalis Causing Disseminated Candidiasis in an Acute Lymphoblastic Leukemia Patient on Posaconazole Prophylaxis.

In this study, we present a rare case of fatal breakthrough Candida tropicalis infection in a patient with acute lymphoblastic leukemia (ALL) while on posaconazole prophylaxis. Then, we explore the mechanisms underlying azole resistance by focusing on enhanced efflux pumps and changes in the azole target enzyme Erg11p, which was encoded by the ERG11 gene. Our study demonstrates that Y132C substitution of Erg11p combined with MDR1 overexpression may be the pan-azole resistance mechanisms in Candida tropicalis.

Successful treatment of rhino-orbital mucormycosis with posaconazole and hyperbaric oxygen therapy.

Mucormycosis is a rare, but invasive infection caused by ubiquitous molds. Amphotericin B and surgery have been known to help improve the outcome. Sporadic case reports support the use of posaconazole in adults. We report a toddler with acute lymphoblastic leukemia who acquired rhino-orbital mucormycosis caused by Rhizopus species at the end of induction chemotherapy. She was successfully treated with multiple surgical debridements, amphotericin B, posaconazole and hyperbaric oxygen therapy. In conclusion, mucormycosis is a serious infection that requires aggressive surgical and medical therapy. To the best of our knowledge the use of posaconazole combined with hyperbaric oxygen therapy has not been reported in a toddler with leukemia and invasive Rhizopus sp. infection. This approach was found to be safe and effective in our patient.

A pilot study of prophylactic ciprofloxacin during delayed intensification in children with acute lymphoblastic leukemia.

BACKGROUND: We hypothesized that prophylactic administration of an appropriate antibiotic following each delayed intensification (DI) in children with acute lymphoblastic leukemia (ALL) would reduce the episodes of fever and bacteremia associated with neutropenia, and hence reduce both the rate and duration of hospitalization. PROCEDURE: All patients in the study were treated according to a modified Medical Research Council United Kingdom ALL XI (MRC UKALL XI) protocol utilizing three DI courses. Between June and December 2000 patients received prophylactic ciprofloxacin following DI courses. The rates of hospitalization and bacteremias were compared to ALL patients who had received between one and three DI courses prior to June 2000. RESULTS: There were 69 patients who received a total of 194 DIs (controls 130; study group 64). The rate of hospitalization was 90% in the controls and 58% in the study group (P < 0.001). The median hospital stay was 10.1 days for controls and 6.0 for the study group (P < 0.001). Intensive care unit admissions were reduced from 12 to 1.5% (P = 0.02). The overall rate of proven bacteremia was reduced from 22 to 9% (P = 0.028). There were no Gram-negative bacteremias in the study group compared to 10 (7.7%) in the controls (P < 0.001). CONCLUSIONS: Compared to historical controls, patients in this study receiving prophylactic ciprofloxacin had a reduced rate and duration of hospitalization and incidence of Gram-negative bacteremia.

Selective oral antimicrobial prophylaxis for the prevention of infection in acute leukaemia-ciprofloxacin versus co-trimoxazole plus colistin. The EORTC-Gnotobiotic Project Group.

230 leukaemic patients were entered into a randomised, prospective, multicentre trial of either ciprofloxacin (1 g/day) or co-trimoxazole (1920 mg/day) plus colistin (800 mg/day) for the prevention of infection during granulocytopenia. Bacteraemia due to resistant gram-negative rods occurred only in the co-trimoxazole-colistin group though both regimens were effective for selective gastrointestinal tract decontamination. However, there were fewer patients without any infective complications (31% vs. 18%: P = 0.02), fewer febrile days [mean (S.D.) 5.9 (1.1) vs. 8.2 (1.4): P = 0.0242], a lower proportion of infective events (0.9 (0.16) vs. 1.2 (0.18): P = 0.005) and fever occurred later (median 19 vs. 14 days: 0.025 less than P less than 0.05) in the co-trimoxazole-colistin group. The choice of prophylactic regimen therefore appears to depend upon whether or not protection against gram-negative infection is required or better systemic prophylaxis overall.