|
Ensure delivery by adding radiocase@email.emedicine.com to
your address book.
Please click
here if you are unable to access the diagnosis page.
BACKGROUND
A 54-year-old African-American woman presents to her
primary care physician's office with a history of
right-sided chest discomfort and intermittent dry cough
of 4 weeks' duration. She denies having a fever, chest
pressure, night sweats, hemoptysis, or weight loss.
However, she does admit to a 25–pack-year history of
smoking and denies using any illicit drugs. She has not
recently traveled outside the United States.
On physical examination, she is afebrile with a normal
heart rate and blood pressure. She is a well-developed,
thin woman who appears to be in no apparent distress.
Findings from the patient's lung and heart examination
are unremarkable. Findings from the remainder of the
examination are also unremarkable.
The chest
radiograph (see Image 1) demonstrates a cavitary mass in
the right upper lobe of the lung. Follow-up chest CT
(see Image 2) shows the same cavitary mass as a
thick-walled lesion in the posterior segment of the
right upper lobe. It measures 4.2 X 5.5 cm.
The patient is initially given a 2-week course of oral
clindamycin. However, follow-up chest images obtained
approximately 1 month afterward fail to reveal any
interval improvement. A positron emission tomographic
(PET) scan is subsequently obtained and shows abnormal
[18F]-fluorodeoxyglucose (FDG) uptake in the right
posterior and apical segments of the right upper lobe
and right hilar lymph node with no other foci of
abnormal uptake. Ultrasonography-guided aspiration and
core lung-mass biopsy are performed, but the results are
nondiagnostic.
The patient eventually
undergoes thoracotomy and right upper lobectomy. Biopsy
specimens are obtained. The pathology specimen shows
evidence of acute necrotizing bronchopneumonia and a
cavitary abscess. Silver staining demonstrates
aggregates of filamentous organisms (see Image 3).
What is the organism, and what is the diagnosis?
|
Hint
Silver staining of the pathology specimen best
demonstrates this organism.
|
|
Authors:
|
Mounir Fertikh, MD,
Pulmonary and Critical Care Division,
Albert Einstein
Medical Center,
Philadelphia, Pa
Michael Walkenstein, MD,
Pulmonary and Critical Care Division,
Albert
Einstein Medical Center,
Philadelphia, Pa
Denise Najjar, MD,
Pathology Division,
Albert Einstein Medical Center,
Philadelphia, Pa
|
|
|
|
|
eMedicine Editor:
|
Rick G. Kulkarni, MD,
Assistant Professor,
Yale School of Medicine,
Section of Emergency Medicine,
Department of Surgery,
Attending
Physician,
Medical Director,
Department of Emergency Services,
Yale-New Haven Hospital, Conn
|
|
|
|
