| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
J Thorac Cardiovasc Surg 2004;127:568-571
© 2004 The American Association for Thoracic Surgery
Clinical-pathologic conference |
a Registrar, Department of Cardiothoracic Surgery, The Alfred, Melbourne, Australia
b Department of Pathology, The Alfred, Melbourne, Australia
c Cardiothoracic Unit, The Alfred, Melbourne, Australia
Received for publication June 20, 2002; accepted for publication July 15, 2002.
* Address for reprints: Marco Larobina, MBBS (Hons), The Alfred, Commercial Road Prahran, Melbourne, Victoria 3181, Australia
marcolarobina{at}hotmail.com
Pancoast syndrome1,2 is a clinical constellation of an apical lung lesion and neurologic sequelae caused by compression of the adjacent lower trunk of the brachial plexus and sympathetic trunk in the superior pulmonary sulcus. The syndrome is usually associated with bronchogenic carcinoma, most commonly squamous cell carcinoma.
This article presents the first reported case of nocardiosis mimicking Pancoast syndrome in the immuncocompetent individual. This highlights the importance of accurate histologic and microbiologic diagnosis before definitive resection of a presumed bronchogenic carcinoma.
 |
Clinical summary |
|---|
 Top Clinical summary DiscussionReferences |
|---|
Her history included carcinoma of the ovary treated with surgical resection and adjuvant chemotherapy with paclitaxel (Taxol) 10 months before presentation. She had a 20 pack-year history of smoking, ceasing 10 years before, and was hospitalized as a child with pneumonia. She had taken only hormone replacement therapy before the diagnosis of the ovarian carcinoma.
She had become unwell in January 2001, with generalized lethargy, an intermittent cough, and a reduction in exercise tolerance from several kilometers to several hundred meters. Left shoulder pain extending down her arm preceded the development of some mild weakness of her left thenar eminence. She had had several upper respiratory illnesses in December but had no fevers or sweats, hemoptysis, change in voice, weight loss, or other neurologic symptoms.
Chest radiography revealed a mass in the superior pulmonary sulcus (Figure 1), which, on computed tomographic (CT) scanning, was shown to arise from the apex of the left lung and extend into the chest wall (Figure 2). This is highly suggestive of invasive carcinoma. Two percutaneous biopsy specimens were nondiagnostic, showing no malignant cells, occasional granulomata, and no organisms. single photon emission computed tomography (SPECT) scanning showed soft tissue inflammation in the left supraclavicular fossa, with involvement of the first rib. The features were considered nonspecific. Anterior mediastinotomy failed to reveal any evidence of metastatic tumor, and the patient was transferred to our institution for definitive surgical intervention.
|
|
Histologic examination showed a necrotizing granulomatous process, with no evidence of malignancy (Figure 3). Silver staining showed occasional fine-branching filaments within the central necrotic tissue, which is consistent with Nocardia species infection.
|
Intravenous amikacin and ceftriaxone were commenced. After 6 weeks, repeat CT brain scanning revealed resolving cerebral abscesses, and oral therapy with trimethoprim/sulfamethoxazole (Bactrim) was commenced to be continued for 1 year.
|
Discussion |
|---|
|
TopClinical summaryDiscussionReferences |
|---|
Shoulder pain is the most common presenting symptom, related to the involvement of the lower trunk of the brachial plexus, the first 3 ribs, the vertebrae, or the parietal pleura. Horner’s syndrome, recurrent laryngeal and phrenic nerve involvement are less common features. Pulmonary manifestations, such as cough, hemoptysis, and dyspnea, occur less often than with centrally located endobronchial lesions.1
The differential diagnoses can be broadly classified into neoplastic and nonneoplastic causes, and evidence of tissue invasion, as seen in this case, is not prima facie evidence of malignancy. Apart from primary bronchogenic carcinoma, other intrathoracic neoplasms (including mesothelioma), hematologic conditions (eg, plasmacytomas and lymphomas), and metastatic deposits are all documented as mimicking the syndrome.
Nonneoplastic conditions include neurogenic thoracic outlet syndromes, inflammatory conditions (eg, Wegener granulomatosis4 and amyloidosis5) and a wide variety of infectious diseases, including tuberculosis, actinomycosis,6 cryptococcosis,7 aspergillosis,8 and pulmonary hydatid cysts.9
Nocardia species infections presenting as Pancoast syndrome have not been previously reported in the literature.
Nocardia species
The nocardiaciae belong to the actinomycetales group of bacteria, which are ubiquitous in the environment.
Impaired cell-mediated immunity, particularly HIV infection, corticosteroid use, chronic granulomatous disease, lymphoid and solid organ neoplasms, and use of cytotoxic agents,10 are common predispositions to infection, as are underlying chronic pulmonary diseases, such as chronic bronchitis and bronchiectasis.11 Up to 40% of patients presenting with pulmonary Nocardia species infections have no predisposing risks for infection.12
Three dominant human pathogens are identified: Nocardia asteroides, the predominant human pathogen that causes pulmonary and disseminated disease9; Nocardia brasiliensis, manifests predominantly as cutaneous and subcutaneous abscesses; and Nocardia otitidiscavarium.
Infection is subdivided into localized disease with single-organ involvement or disseminated, with multiple organ involvement, and a predilection for central nervous system seeding. Cerebral abscesses are present in 45% of cases, but involvement of most body tissues has been reported.9
The presentation of N asteroides ranges from an acute suppurative pneumonia to a more chronic presentation mimicking carcinoma, and as in this case, diagnosis is difficult because of the nonspecific clinical and radiologic features. Early infection manifests as an acute inflammatory reaction dominated by neutrophils, whereas lymphocytes dominate chronic disease. The granulomatous appearance, as reported here, is rare in the literature and probably resembles the more immunocompetent response to chronic infection.8
Diagnosis
This case highlights the management difficulty presented by solitary pulmonary masses in which a tissue diagnosis proves elusive. Diagnosis of pulmonary masses relies on cytologic, histologic, and microbiologic examination of tissue. For apical tumors, percutaneous biopsy is reported as the modality of choice, with a 95% sensitivity.13 The accuracy of this modality in the diagnosis of Nocardia species infection is unclear. In some case series of pulmonary nocardiosis, results of sputum cultures were positive in up to 90% of patients, making routine sputum microscopy and culture an important adjunct to sputum cytology.9
The cornerstone of diagnosis of Nocardia species remains identification of branching filaments in tissue section, Gram staining, and culture. Different species and subspecies show variable susceptibility to amikacin, third-generation cephalosporins, imipenem-meropenem, and sulfur-based antimicrobials. The optimal duration of therapy, the role for oral versus intravenous therapy, and the value of multiagent antimicrobial use are not well defined.
Conclusion
Although the initiation of treatment for apical lung lesions was once advocated without the acquisition of a precise histologic diagnosis,14 the recognition that Pancoast syndrome can be caused by a wide variety of conditions mandates that an accurate diagnosis is made in any pulmonary mass that appears clinically and radiologically to be a bronchogenic carcinoma. CT-guided percutaneous biopsy remains the modality of choice, but where the diagnosis remains elusive, open biopsy is required. In addition to histopathology, all lung biopsy specimens should routinely be sent for microscopy and culture if the wide variety of infectious diseases that can mimic lung carcinoma, such as nocardiosis, are to be diagnosed before surgical resection.
|
References |
|---|
|
TopClinical summaryDiscussionReferences |
|---|
This article has been cited by other articles:
|
|
 |
|
  H. C. Suen, R. A. Summa, A. Babich, E. C. Ernst, P. Zinser, W. C. Feliciano, and J. H. Rice Methicillin-resistant Staphylococcus aureus infection causing Pancoast syndrome J. Thorac. Cardiovasc. Surg., July 1, 2006; 132(1): 183 - 184. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
