[Retrospective study of 25 cases of pulmonary mucormycosis in acute leukaemia]

In acute leukaemia (AL), the occurrence of pulmonary mucormycosis (PM), the incidence of which is increasing, as a result of chemotherapy induced marrow aplasia, remains a life threatening complication.

Analysis of clinical, biological and thoracic CT characteristics of patients with PM developing during the treatment of AL between 2000 and 2015. Day 0 (D0) was defined as the day with first CT evidence of PM.

Among 1193 patients, 25 cases of PM were recorded during 2099 episodes of bone marrow aplasia. At time of diagnosis of PM, 24/25 patients had been neutropenic for a median of 12 days. None of the patients had diabetes mellitus. On initial CT (D0), the lesion was solitary in 20/25 cases and a reversed halo sign (RHS) was observed in 23/25 cases. From D1 to D7, D8 to D15 and after D15, RHS was seen in 100 %, 75 % and 27 % of cases, respectively. A tissue biopsy was positive in 17/18 cases. The detection of circulating Mucorales DNA in serum was positive in 23/24 patients and in 97/188 serum specimens between D-9 and D9. Bronchoalveolar lavage contributed to diagnosis in only 3/21 cases. The antifungal treatment was mainly based on liposomal amphotericin B combined with, or followed by, posaconazole. A pulmonary surgical resection was performed in 9/25 cases. At 3 months, 76 % of patients were alive and median overall survival was 14 months.

In AL, early use of CT could improve the prognosis of PM. The presence of a RHS on CT suggests PM and is an indication for prompt antifungal treatment.