AJR 2004; 183:1224-1226
© American Roentgen Ray Society
Invasive Aspergillosis of the Mediastinum and Left Hilum: CT Features
Bachir Taouli1,2,
Mehdi Cadi1,
Véronique Leblond3 and
Philippe A. Grenier1
1 Department of Radiology, Hôpital
Pitié-Salpêtrière-Assistance Publique-Hôpitaux de
Paris, Université Pierre et Marie Curie, 83, Boulevard de
l'Hôpital, Paris 75013, France.
2 Present address: Department of Radiology, New York University Medical Center,
560 First Ave., TCH-HW 202, New York NY 10016-6497.
3 Department of Hematology, Hôpital
Pitié-Salpêtrière-Assistance Publique-Hôpitaux de
Paris, Université Pierre et Marie Curie, Paris 75013, France.
Received July 21, 2003;
accepted after revision December 7, 2003.
Address correspondence to B. Taouli
(bachir.taouli{at}med.nyu.edu).
Introduction
Invasive pulmonary aspergillosis is a serious complication in
immunocompromised patients, occurring mostly in patients with hematologic
malignancies who are undergoing chemotherapy and in patients who have
undergone bone marrow and organ transplantation and concomitant
immunosuppressive therapy [1].
Extension of invasive pulmonary aspergillosis to the mediastinum and proximal
pulmonary arteries has been reported only rarely
[2-4].
We report the case of a patient with fulminant invasive pulmonary
aspergillosis with extensive necrotic involvement of the mediastinum, left
pulmonary artery, and left pulmonary veins.
Case Report
A 71-year-old man was admitted for chemotherapy for treatment of
non-Hodgkin's lymphoma involving the lymph nodes and bone marrow. The initial
chest CT scan obtained 1 month before the patient began treatment was
unremarkable. On day 6 after chemotherapy induction, the patient developed a
fever and neutropenia (absolute neutrophil count, 364/µL). The
fever persisted despite administration of broad-spectrum IV antibiotics. The
results of all blood cultures remained negative for bacteria and fungi. On day
9, the patient exhibited chest symptoms (coughing and blood in the sputum).
Portable posteroanterior chest radiography showed bilateral areas of
consolidation, predominantly in the left lung
(Fig. 1A). Contrast-enhanced
helical chest CT showed a necrotic mediastinal masslike infiltrate invading
the left pulmonary artery, left pulmonary veins, and left atrium
(Fig. 1B). A low-attenuation
filling defect compatible with thrombus was present in the left pulmonary
artery, with emphysematous dissection of the pulmonary artery wall
(Fig. 1C). Also present were
pneumomediastinum and bilateral areas of alveolar consolidation, predominantly
in the left lung, with surrounding areas of ground-glass opacity equivalent to
a halo sign as well as bilateral pleural effusion
(Fig. 1D).

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Fig. 1A. 71-year-old man with non-Hodgkin's lymphoma and invasive
pulmonary aspergillosis. Posteroanterior chest radiograph shows areas of
consolidation in both lungs, predominantly in left lower lobe
(arrows).
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Fig. 1B. 71-year-old man with non-Hodgkin's lymphoma and invasive
pulmonary aspergillosis. Transverse contrast-enhanced chest CT scan
(mediastinal window settings) obtained at level of left pulmonary artery shows
necrotic mediastinal masslike infiltrate invading left pulmonary artery
(straight arrows), with thrombus and emphysematous dissection of
pulmonary artery wall (curved arrows).
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Fig. 1C. 71-year-old man with non-Hodgkin's lymphoma and invasive
pulmonary aspergillosis. Transverse contrast-enhanced chest CT scan (lung
window settings) obtained at same level as B shows alveolar
consolidation with surrounding ground-glass opacities (arrows) of
left lung and, to lesser extent, of right lung.
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Fig. 1D. 71-year-old man with non-Hodgkin's lymphoma and invasive
pulmonary aspergillosis. Transverse contrast-enhanced chest CT scan
(mediastinal window settings) obtained at level of left pulmonary veins shows
necrotic mass invading left pulmonary veins and left atrium
(arrowhead). Bilateral pleural effusion is present.
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Invasive pulmonary aspergillosis was suspected and administration of IV
itraconazole was started shortly thereafter. The results of two ELISAs
(enzyme-linked immunosorbent assays) (Sanofi-Biorad) were positive for serum
galactomannan (antigen of Aspergillus fungus) (5 ng/mL; normal
result, < 1.0 ng/mL), confirming the diagnosis of invasive aspergillosis
[5,
6]. Bronchoalveolar lavage was
not performed because of the poor respiratory condition of the patient.
Despite anti-fungal therapy, the patient presented with massive fatal
hemoptysis and died on day 14 after initiation of chemotherapy. No autopsy was
performed.
Discussion
Aspergillus fumigatus is a common commensal of the human airways.
However, in immunocompromised patientsespecially those with severe
neutropeniatransbronchial invasion can occur, and the subsequent
invasion of the small pulmonary vessels with hemorrhage and pulmonary infarct
can result in invasive pulmonary aspergillosis, which is responsible for a
mortality rate as high as 86% in treated patients
[1]. Rare cases of involvement
of the proximal pulmonary arteries, the heart, and the aorta have been
reported in patients with invasive pulmonary aspergillosis
[2-4,
7,
8], but a case of necrotic
mediastinitis with massive pulmonary artery thrombosis and emphysematous
dissection of the pulmonary artery wall have never been described previously
in that clinical setting, to our knowledge.
The explanation for the presence of pneumomediastinum and gas dissection of
the pulmonary artery wall is uncertain; it could be possibly related to
necrotizing bronchitis and pulmonary infarction with gangrenous changes due to
invasion and occlusion of medium- and large-sized pulmonary vessels
[9]. An autopsy was not
performed in our patient, but in a previous case report describing a patient
with massive pulmonary embolism in relation with invasive pulmonary
aspergillosis, the autopsy showed obstruction of the main pulmonary artery
secondary to fungal infection and endothelial invasion with secondary
thrombosis [3]. In our patient,
the diagnosis of invasive aspergillosis was made on the basis of a serum
galactomannan (an essential exoantigen of the Aspergillus fungus)
assay using ELISA, which is known to have a high sensitivity (
94.8%) and
specificity (
98.8%) in high-risk patients with hematologic malignancies
[5,
6].
Because the findings of chest radiography are often nonspecific, several
previous studies have advocated the use of early lung CT examinations to
diagnose invasive pulmonary aspergillosis and institute prompt antifungal
therapy. Characteristic but nonpathognomonic CT signs of early invasive
pulmonary aspergillosis are represented by segmental areas of consolidation or
nodules with surrounding ground-glass opacity (the halo sign), corresponding
to surrounding hemorrhage
[10]. After a patient has been
treated and has recovered from neutropenia, cavitation (the air crescent sign)
can develop within the pulmonary nodules
[10]. However, similar
findings may be encountered in patients with other fungal infections such as
mucormycosis. Other studies have shown the usefulness of biologic tests, such
as fungal antigenemia (galactomannan) in the serum
[5,
6] or bronchoalveloar fluid,
and open lung biopsy to diagnose invasive pulmonary aspergillosis.
In conclusion, this case illustrates the potential of Aspergillus
species to cause extensive necrotic mediastinal invasion and pulmonary artery
thrombosis in neutropenic patients, with a dismal prognosis.
References
- Denning DW. Therapeutic outcome in invasive aspergillosis.
Clin Infect Dis1996; 23:608
-615[Medline]
- Choyke PL, Edmonds PR, Markowitz RI, Kleinman CS, Laks H. Mycotic
pulmonary artery aneurysm: complication of Aspergillus endocarditis.
AJR 1982;138:1172
-1175[Free Full Text]
- Kirshenbaum JM, Lorell BH, Schoen FJ, Bettmann MA, Thompson GB.
Angioinvasive pulmonary aspergillosis: presentation as massive pulmonary
saddle embolism in an immunocompromised patient. J Am Coll
Cardiol 1985;6:486
-489[Abstract]
- Hayashi H, Takagi R, Onda M, Kumazaki T. Invasive pulmonary
aspergillosis occluding the descending aorta and left pulmonary artery: CT
features. J Comput Assist Tomogr1994; 18:492
-494[Medline]
- Herbrecht R, Letscher-Bru V, Oprea C, et al. Aspergillus
galactomannan detection in the diagnosis of invasive aspergillosis in cancer
patients. J Clin Oncol2002; 20:1898
-1906[Abstract/Free Full Text]
- Maertens J, Van Eldere J, Verhaegen J, Verbeken E, Verschakelen J,
Boogaerts M. Use of circulating galactomannan screening for early diagnosis of
invasive aspergillosis in allogeneic stem cell transplant recipients.
J Infect Dis2002; 186:1297
-1306[Medline]
- Corrigan C, Horner SM. Aspergillus endocarditis in
association with a false aortic aneurysm. Clin Cardiol1988; 11:430
-432[Medline]
- Katz JF, Yassa NA, Bhan I, Bankoff MS. Invasive aspergillosis
involving the thoracic aorta: CT appearance. AJR1994; 163:817
-819[Free Full Text]
- Krick JA, Remington JS. Opportunistic invasive fungal infections in
patients with leukaemia lymphoma. Clin Haematol1976; 5:249
-310[Medline]
- Kuhlman JE, Fishman EK, Burch PA, Karp JE, Zerhouni EA, Siegelman
SS. CT of invasive pulmonary aspergillosis. AJR1988; 150:1015
-1020[Free Full Text]

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