Usefulness of molecular biology performed with formaldehyde-fixed paraffin embedded tissue for the diagnosis of combined pulmonary invasive mucormycosis and aspergillosis in an immunocompromised patient.
Immunocompromised patients who develop invasive filamentous mycotic infections can be efficiently treated if rapid identification of the causative fungus is obtained. We report a case of fatal necrotic pneumonia caused by combined pulmonary invasive mucormycosis and aspergillosis in a 66 year-old renal transplant recipient. Aspergillus was first identified during the course of the disease by cytological examination and culture (A. fumigatus) of bronchoalveolar fluid. Hyphae of Mucorales (Rhizopus microsporus) were subsequently identified by culture of a tissue specimen taken from the left inferior pulmonary lobe, which was surgically resected two days before the patient died. Histological analysis of the lung parenchyma showed the association of two different filamentous mycoses for which the morphological features were evocative of aspergillosis and mucormycosis. However, the definitive identification of the associative infection was made by polymerase chain reaction (PCR) performed on deparaffinized tissue sections using specific primers for aspergillosis and mucormycosis. This case demonstrates that discrepancies between histological, cytological and mycological analyses can occur in cases of combined mycotic infection. In this regard, it shows that PCR on selected paraffin blocks is a very powerful method for making or confirming the association of different filamentous mycoses and that this method should be made available to pathology laboratories.
Hofman
Véronique
V
Laboratory of Clinical and Experimental Pathology, Louis Pasteur Hospital, 30 avenue de la voie romaine, Nice, France. hofman.p@chu-nice.fr
Dhouibi
Abdelmajid
A
Butori
Catherine
C
Padovani
Bernard
B
Gari-Toussaint
Martine
M
Garcia-Hermoso
Dea
D
Baumann
Michèle
M
Vénissac
Nicolas
N
Cathomas
Gieri
G
Hofman
Paul
P
D000368:Aged; D001232:Aspergillus fumigatus / Q000235:genetics / Q000302:isolation & purification; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D017809:Fatal Outcome; D005404:Fixatives; D005557:Formaldehyde; D006801:Humans; D016867:Immunocompromised Host; D007166:Immunosuppressive Agents / Q000009:adverse effects*; D055744:Invasive Pulmonary Aspergillosis / Q000175:diagnosis* / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D016030:Kidney Transplantation / Q000009:adverse effects; D008168:Lung / Q000382:microbiology / Q000473:pathology; D008297:Male; D009091:Mucormycosis / Q000175:diagnosis* / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D009336:Necrosis; D016612:Paraffin Embedding; D011014:Pneumonia / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D012233:Rhizopus / Q000235:genetics / Q000302:isolation & purification; D013194:Staining and Labeling; D016707:Tissue Fixation / Q000379:methods*; D014057:Tomography, X-Ray Computed
D005404:Fixatives; D007166:Immunosuppressive Agents; D005557:Formaldehyde