Improving Diagnosis of Pulmonary Mucormycosis: Leads From a Contemporary National Study of 114 Cases

Abstract

Pulmonary mucormycosis (PM) is a life-threatening invasive mold infection. Diagnosis of mucormycosis is challenging and often delayed, resulting in higher mortality. Are the disease presentation of PM and contribution of diagnosis tools influenced by the patient underlying condition? All PM cases from six French teaching hospitals between 2008 and 2019 were retrospectively reviewed. Cases were defined according to updated EORTC/MSG criteria with the addition of diabetes and trauma as host factors and positive serum or tissue PCR as mycological evidence. Thoracic CT scans were reviewed centrally. One hundred and fourteen cases of PM were recorded, including 40% disseminated forms. Main underlying conditions were hematological malignancy (49%), allogeneic hematopoietic stem-cell transplantation (21%), and solid organ transplantation (17%). When disseminated, main dissemination sites were the liver (48%), spleen (48%), brain (44%), and kidneys (37%). Radiological presentation included consolidation (58%), pleural effusion (52%), reversed halo sign (RHS, 26%), halo sign (24%), vascular abnormalities (26%), and cavity (23%). Serum qPCR was positive in 42/53 patients (79%) and bronchoalveolar lavage (BAL) in 46/96 patients (50%). Transthoracic lung biopsy was diagnostic in 8/11 (73%) patients with non-contributive BAL. Overall 90-day mortality was 59%. Neutropenic patients displayed more frequently an angioinvasive presentation including RHS and disseminated disease (p<0.05). Serum qPCR was more contributive in neutropenic patients (91% vs 62%, p=0.02) and BAL in non-neutropenic patients (69% vs 41%, p=0.02). Serum qPCR was more frequently positive in patients with a >3cm main lesion (91% vs 62%, p=0.02). Overall, positive qPCR was associated with an early diagnosis (p=0.03) and treatment onset (p=0.01). Neutropenia and radiological findings influence disease presentation and contribution of diagnostic tools during PM. Serum qPCR is more contributive in neutropenic patients and BAL examination in non-neutropenic patients. Lung biopsies are highly contributive in case of non-contributive BAL.