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Pulmonary actinomycosis—A master of disguise
Journal of Infection (1995) 31, 165-169
CASE REPORT
Pulmonary Actinomycosis--A Master of Disguise H. M. Shannon, A. J. A Wightman and F. A. Carey Department of Radiology, City Hospital Edinburgh, U.K, Accepted for publication 26 January 1995
Three cases of pulmonary actinomycosis are described. In all three cases, an initial diagnosis of pulmonary malignant neoplasia was made. The correct diagnosis was made histologically after the three patients underwent either lobectomy or pneumonectomy. All patients recovered after appropriate therapy. Pulmonary actinomycosis should always be considered in the differential diagnosis of pulmonary neoplasia, especially in young adults.
Introduction
X-ray showed an ill defined opacity at the right apex and consolidation in the basal segments of the left Puhnonary actinomycosis is rare in Britain today. It is lower lobe. Thoracic CT-scan revealed a mass of difficult to diagnose mainly because it closely mimics intrapulmonary soft tissue with associated pleural reother more c o m m o n diseases but is eminently treatable action but no mediastinal involvement. A perfusion by antibiotic therapy. We present three cases referred lung scan showed abnormalities which matched those to the same thoracic surgical unit within the period of the chest X-ray only. Bronchoscopy revealed mucosal of a year. In all three, a presurgical diagnosis of inflammation in the right upper lobe bronchi without pulmonary malignant neoplasia was made and all any endobronchial lesion. underwent either a lobectomy or pneumonectomy. The Initially, the symptoms improved with antibiotic correct diagnosis of pulmonary actinomycosis was therapy but a chest X-ray, at an outpatient visit 4 made histologically. All the patients recovered after weeks later, showed no change in the radiological appropriate antibiotic therapy. Although uncommon, appearances. pulmonary actinomycosis should always be considered Three months later, the patient returned with further in the differential diagnosis of pulmonary neoplasia, pleuritic pain and haemoptysis as well as a cough particularly in atypical cases such as those presenting which produced green sputum. A chest X-ray at that in young adults. time showed that the right apical lesion had increased in size. An air bronchogram was present within it and the left basal changes had persisted (Figure 1). Case 1 Lymphoma was considered as a likely cause of the A 30-year-old male New Zealand sheep shearer pre- increasing size of the lesion in the right upper lobe. sented with a history of intermittent pleuritic chest Surgical exploration was therefore undertaken. pain and haemoptysis following a recent flight from At operation, a large apical mass was found, adherent Australia to Britain. He had no medical history of note to the pleura, It was displacing and compressing the and did not smoke. azygos vein and superior vena cava. A right upper On examination he appeared well, was afebrile, lobectomy was performed. and had no lymphadenopathy or finger clubbing. Macroscopically, the lung showed marked pleural Examination of the chest revealed diminution in breath thickening at the apex with necrotic tissue extending sounds at the left base but no added sounds. He had into the chest wall. Multiple areas of yellow cona raised white blood cell count of 13.1 x 109/1 with solidation with focal necrosis were evident. Histo74% neutrophils and a raised ESR of 74 m m / h . Chest logically, the appearances were those of necrotising pneumonia with characteristic colonies of Actinomyces in the necrotic area (Figure 2). Address correspondence to: Dr H. Shannon, Department of Radiology, Following treatment with a combination of ampicillin Royal Infirmary of Edinburgh, Lauriston Place, Edinburgh EH3 9YW, and metronidazole, the patient made a good recovery. U.K. 0163-4453/95/050165 + 05 $12.00/0
© 1995 The British Society for the Study of Infection
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Pulmonary Actinomycosis
Figure 1. Chest X-ray showing right apical opacity with air bronchogram and left basal opacity.
Case 2 A 55-year-old architect presented with right-sided pleuritic chest pain and a cough which produced grey
Figure 2. Photomicrograph showing a characteristic colony of actinomyces in an area of abscess formation (haematoxylin and eosin x 100).
sputum. His only past illness was diphtheria as a child. He had smoked 30 cigarettes per day for m a n y years and consumed 40 units of alcohol per week. On examination, the patient was afebrile and without finger clubbing or lymphadenopathy. There was dullness to percussion in the right midzone of the chest with diminution of breath sounds. Initial investigations revealed a raised ESR of 80 m m / h, a white blood cell count of 12.4 x 109/1 with 82% neutrophils and a thrombocytosis of 5 8 7 x 109/1. A chest X-ray showed consolidation with cavitation in the apical segment of the right lower lobe (Figure 3). A lung perfusion scan revealed a scintigraphic defect which matched the X-ray abnormality but the rest of the lungs appeared normal. The patient was initially treated orally with erythromycin. After 6 weeks there was only partial resolution of the radiographic abnormality. Bronchoscopy revealed inflammatory changes in the anterior and posterior segments of the right lower lobe but no endobronchial lesions were seen. Examination of bronchial brushings showed epithelial cellular changes suspicious of malignant neoplasia. After a further 6 weeks there was a marked increase in size of the right-sided opacity and an associated pleural-based mass was apparent (Figure 4). The patient now complained of localised tenderness of the chest wall in the region of this pleural mass. CT-scan of the chest demonstrated an enhancing pleural-based right midzone opacity with irregular margins (Figure 5).
H. M. Shannon et al.
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Figure 5. Computerised tomography of the chest demonstrating an enhanced right midzone opacity related to the pleura.
Figure 3. Chest X-ray showing an opacity in the apical segment of right lower lobe with cavitation.
A differential diagnosis of peripheral bronchogenic carcinoma or mesothelioma was made. The patient was referred for thoracotomy at which it was found necessary to resect the right lung together with part of the chest wall and diaphragm.
Macroscopically, there was seen a 7 cm partly necrotic mass extending across the fissure between the upper and lower lobes and into the soft tissues between the ribs. Multiple smaller white nodules based on small bronchi were seen in the surrounding parenchyma. Microscopically, extensive abscess formation was seen and colonies of actinomyces were easily visible. In addition, small fragments of foreign material, probably of vegetable origin, were identified. Initially, the patient made a good recovery but 2 months later, despite continuing antibiotic therapy, he again developed right-sided chest pain. Repeated chest X-rays, chest CT and aspiration of the postpneumonectomy space failed to demonstrate any recurrence of actinomycosis and he remains under continuing surveillance.
Case. 3
Figure 4. Chest X-ray showing a more extensive right pulmonary opacily with an associated mass related to the pleura.
A 38-year-old man presented with three episodes of right-sided pleuritic chest pain over the course of a year. Unlike the first two episodes which responded to antibiotic treatment, the third did not and was associated with blood-streaked sputum. There was no significant past medical history. He smoked 20 cigarettes per day. Physical examination was normal. Haematological and biochemical indices were unremarkable. An initial chest X-ray showed a poorly defined mass in the right lower zone with some adjacent pleural thickening. After 2 months, both the pulmonary and plenral opacities had increased in size. Bronchoscopy
168
Pulmonary Actinomycosis
demonstrated some fresh blood in the right lower lobe bronchus but n o endothelial lesions. CT-scan of the chest confirmed the presence of a large opacity in the right lower lobe with associated pleural thickening. A diagnosis of pulmonary neoplasm was made. Mediastinoscopy showed enlarged paratracheal nodes which, histologically, were said to be 'reactive'. A rightsided thoractomy was performed. During this, a large mass involving the middle and lower lobes and adherent to the chest wall and diaphragm was removed. Pathological examination again revealed necrotising tissue in which actinomyces could be seen. In this instance, the specimen had been received fresh so material was sent for microbiological examination. Actinomyces israelii was isolated. With antibiotic therapy the patient made a good recovery.
Discussion Pulmonary actinomycosis is usually caused by Actinornyces israelii, a Gram-positive organism, which often inhabits the mouths of healthy people. Pulmonary infection is thought to arise from inhalation of oral material while dental disease and general debility are regarded as predisposing factors. I In one of our three cases, there was direct evidence of inhaled foreign material. Moreover, it is interesting that in all three cases the right lung was involved in a segmental distribution that accords with aspiration. Actinomycosis usually responds to treatment with c o m m o n antibiotics and most cases recover well with prolonged therapy. 2 Actinomycosis is more often a cervico-facial or abdominal, t h a n a thoracic infection. There was pulm o n a r y involvement in only one of 36 cases of actinomycosis reported in the U.K. in 19701 and in three of 43 cases reported in 1976. 3 The classical appearance of chronically draining sinuses is now hardly ever seen in this country, presumably because of the widespread use of antibiotics. The diagnostic difficulty of pulmonary actinomycosis arises from a lack of specific findings. The clinical symptoms are c o m m o n to m a n y chest diseases and are, most often, cough with sputum, chest pain, weight loss and haemoptysis. 4 The presence of Actinomyces in the sputum is unhelpful because the organism is a c o m m o n oral commensal. Chest radiographic appearances are also variable. Flynn and Felson, 5 in a review of 15 cases in 1970, reported pleural effusions, empyema and pleural thickening as the most frequent findings. Masses, infiltrates, with and without cavitation, as well as fibrotic lesions were often seen also. In their conclusion,
they suggested several features which should arouse suspicion of actinomycosis. These are: extension of pulmonary lesions through the thoracic wall, pulmonary lesions associated with periostitis and destruction of ribs as well as extension of lesions across interlobar fissures. Frank and Strickland, ~ however, in a review of six cases in 1974, found radiographic evidence of rib involvement in only one case and of pleural disease in two cases. CT is helpful in demonstrating the extent and relationship of pulmonary and chest wall disease but has no specific diagnostic features in this context. 7 The organism m a y be recovered by means of percutaneous needle biopsy and transbronchial or open lung biopsy but the diagnosis is often made histologically by Gram-staining. The abcesses are typically surrounded by granulation tissue with a variable degree of fibrosis. They contain masses of polymorphonuclear leucocytes with which so-called 'sulphur granules' m a y be associated. The organisms can usually be seen in the centre of the granules. 8 A positive biopsy will prevent the patient from undergoing unnecessary surgery so that biopsy should always be considered in the investigation of a solitary or atypical pulmonary lesion. Recently, there have been several reports of actinomycosis presenting as endobronchial lesions during bronchoscopy. A diagnosis was then made from bronchial biopsy material and washings. 9' 10 The masquerading of pulmonary actinomycosis as pulmonary malignant neoplasia has been recognised for m a n y years, n In view of the declining incidence of the disease, however, the cases presented here serve as a reminder of the diagnostic difficulty that pulmonary actinomycosis m a y present. Such a diagnosis should always be borne in mind in the differential diagnosis of thoratic malignant neoplasia, particularly in younger adults in w h o m malignant neoplasia is less common. Preoperative recognition in our three patients would have prevented thoracotomy and, in one case, quite extensive resection of the chest wall.
References 1 Brown JR. Human Actinomycosis: a study of 181 subjects. Human Pathol 1973; 4: 319-330. 2 Slade PR, Slesser BV, Southgate J. Thoracic actinomycosis. Thorax 1973; 28: 73-85. 3 Epidemiology.Br MedJ 1977; 1: 1037. 4 Bates M, Cruickshank G. Thoracic actinomycosis.Thorax 1957; 12: 99-123. 5 Flynn MW, Felson B. The Roentgen manifestations of thoracic actinomycosis. Am J Radiol 1970; 110: 707-716. 6 Frank P, Strieldand B. Pulmonary actinomycosis.BrJ Radiol 1974; 47: 373-378. 7 Webb W, Sagel SS. Actinomycosis involving the chest wall: CT
H. M. Shannon et aL findings. Am J Radiol 1982; 139: 1007-1009. 8 Fraser RG, Pare JAP. In: Diagnosis of disease of the chest, Philadelphia: Saunders, 1989; 1022-1028. 9 Lau K. Bndobronchial actinomycosis mimicking pulmonary neoplasm. Thorax 1992; 47: 664-665.
169
10 Ariel I, Breuer R, Kamal NS, Ben-Dov I, Mogie P, Rosemann E. Endobronchial actinomycosis simulating bronchogenic carcinoma. Chest 1991; 99: 493-495, 11 Prather JR, Eastridge CE, Hughes FA, McCaugan JJ. Actinomycosis of the thorax. Ann Thorac Surg 1970; 9: 307-312.
CASE REPORT
Pulmonary Actinomycosis--A Master of Disguise H. M. Shannon, A. J. A Wightman and F. A. Carey Department of Radiology, City Hospital Edinburgh, U.K, Accepted for publication 26 January 1995
Three cases of pulmonary actinomycosis are described. In all three cases, an initial diagnosis of pulmonary malignant neoplasia was made. The correct diagnosis was made histologically after the three patients underwent either lobectomy or pneumonectomy. All patients recovered after appropriate therapy. Pulmonary actinomycosis should always be considered in the differential diagnosis of pulmonary neoplasia, especially in young adults.
Introduction
X-ray showed an ill defined opacity at the right apex and consolidation in the basal segments of the left Puhnonary actinomycosis is rare in Britain today. It is lower lobe. Thoracic CT-scan revealed a mass of difficult to diagnose mainly because it closely mimics intrapulmonary soft tissue with associated pleural reother more c o m m o n diseases but is eminently treatable action but no mediastinal involvement. A perfusion by antibiotic therapy. We present three cases referred lung scan showed abnormalities which matched those to the same thoracic surgical unit within the period of the chest X-ray only. Bronchoscopy revealed mucosal of a year. In all three, a presurgical diagnosis of inflammation in the right upper lobe bronchi without pulmonary malignant neoplasia was made and all any endobronchial lesion. underwent either a lobectomy or pneumonectomy. The Initially, the symptoms improved with antibiotic correct diagnosis of pulmonary actinomycosis was therapy but a chest X-ray, at an outpatient visit 4 made histologically. All the patients recovered after weeks later, showed no change in the radiological appropriate antibiotic therapy. Although uncommon, appearances. pulmonary actinomycosis should always be considered Three months later, the patient returned with further in the differential diagnosis of pulmonary neoplasia, pleuritic pain and haemoptysis as well as a cough particularly in atypical cases such as those presenting which produced green sputum. A chest X-ray at that in young adults. time showed that the right apical lesion had increased in size. An air bronchogram was present within it and the left basal changes had persisted (Figure 1). Case 1 Lymphoma was considered as a likely cause of the A 30-year-old male New Zealand sheep shearer pre- increasing size of the lesion in the right upper lobe. sented with a history of intermittent pleuritic chest Surgical exploration was therefore undertaken. pain and haemoptysis following a recent flight from At operation, a large apical mass was found, adherent Australia to Britain. He had no medical history of note to the pleura, It was displacing and compressing the and did not smoke. azygos vein and superior vena cava. A right upper On examination he appeared well, was afebrile, lobectomy was performed. and had no lymphadenopathy or finger clubbing. Macroscopically, the lung showed marked pleural Examination of the chest revealed diminution in breath thickening at the apex with necrotic tissue extending sounds at the left base but no added sounds. He had into the chest wall. Multiple areas of yellow cona raised white blood cell count of 13.1 x 109/1 with solidation with focal necrosis were evident. Histo74% neutrophils and a raised ESR of 74 m m / h . Chest logically, the appearances were those of necrotising pneumonia with characteristic colonies of Actinomyces in the necrotic area (Figure 2). Address correspondence to: Dr H. Shannon, Department of Radiology, Following treatment with a combination of ampicillin Royal Infirmary of Edinburgh, Lauriston Place, Edinburgh EH3 9YW, and metronidazole, the patient made a good recovery. U.K. 0163-4453/95/050165 + 05 $12.00/0
© 1995 The British Society for the Study of Infection
166
Pulmonary Actinomycosis
Figure 1. Chest X-ray showing right apical opacity with air bronchogram and left basal opacity.
Case 2 A 55-year-old architect presented with right-sided pleuritic chest pain and a cough which produced grey
Figure 2. Photomicrograph showing a characteristic colony of actinomyces in an area of abscess formation (haematoxylin and eosin x 100).
sputum. His only past illness was diphtheria as a child. He had smoked 30 cigarettes per day for m a n y years and consumed 40 units of alcohol per week. On examination, the patient was afebrile and without finger clubbing or lymphadenopathy. There was dullness to percussion in the right midzone of the chest with diminution of breath sounds. Initial investigations revealed a raised ESR of 80 m m / h, a white blood cell count of 12.4 x 109/1 with 82% neutrophils and a thrombocytosis of 5 8 7 x 109/1. A chest X-ray showed consolidation with cavitation in the apical segment of the right lower lobe (Figure 3). A lung perfusion scan revealed a scintigraphic defect which matched the X-ray abnormality but the rest of the lungs appeared normal. The patient was initially treated orally with erythromycin. After 6 weeks there was only partial resolution of the radiographic abnormality. Bronchoscopy revealed inflammatory changes in the anterior and posterior segments of the right lower lobe but no endobronchial lesions were seen. Examination of bronchial brushings showed epithelial cellular changes suspicious of malignant neoplasia. After a further 6 weeks there was a marked increase in size of the right-sided opacity and an associated pleural-based mass was apparent (Figure 4). The patient now complained of localised tenderness of the chest wall in the region of this pleural mass. CT-scan of the chest demonstrated an enhancing pleural-based right midzone opacity with irregular margins (Figure 5).
H. M. Shannon et al.
167
Figure 5. Computerised tomography of the chest demonstrating an enhanced right midzone opacity related to the pleura.
Figure 3. Chest X-ray showing an opacity in the apical segment of right lower lobe with cavitation.
A differential diagnosis of peripheral bronchogenic carcinoma or mesothelioma was made. The patient was referred for thoracotomy at which it was found necessary to resect the right lung together with part of the chest wall and diaphragm.
Macroscopically, there was seen a 7 cm partly necrotic mass extending across the fissure between the upper and lower lobes and into the soft tissues between the ribs. Multiple smaller white nodules based on small bronchi were seen in the surrounding parenchyma. Microscopically, extensive abscess formation was seen and colonies of actinomyces were easily visible. In addition, small fragments of foreign material, probably of vegetable origin, were identified. Initially, the patient made a good recovery but 2 months later, despite continuing antibiotic therapy, he again developed right-sided chest pain. Repeated chest X-rays, chest CT and aspiration of the postpneumonectomy space failed to demonstrate any recurrence of actinomycosis and he remains under continuing surveillance.
Case. 3
Figure 4. Chest X-ray showing a more extensive right pulmonary opacily with an associated mass related to the pleura.
A 38-year-old man presented with three episodes of right-sided pleuritic chest pain over the course of a year. Unlike the first two episodes which responded to antibiotic treatment, the third did not and was associated with blood-streaked sputum. There was no significant past medical history. He smoked 20 cigarettes per day. Physical examination was normal. Haematological and biochemical indices were unremarkable. An initial chest X-ray showed a poorly defined mass in the right lower zone with some adjacent pleural thickening. After 2 months, both the pulmonary and plenral opacities had increased in size. Bronchoscopy
168
Pulmonary Actinomycosis
demonstrated some fresh blood in the right lower lobe bronchus but n o endothelial lesions. CT-scan of the chest confirmed the presence of a large opacity in the right lower lobe with associated pleural thickening. A diagnosis of pulmonary neoplasm was made. Mediastinoscopy showed enlarged paratracheal nodes which, histologically, were said to be 'reactive'. A rightsided thoractomy was performed. During this, a large mass involving the middle and lower lobes and adherent to the chest wall and diaphragm was removed. Pathological examination again revealed necrotising tissue in which actinomyces could be seen. In this instance, the specimen had been received fresh so material was sent for microbiological examination. Actinomyces israelii was isolated. With antibiotic therapy the patient made a good recovery.
Discussion Pulmonary actinomycosis is usually caused by Actinornyces israelii, a Gram-positive organism, which often inhabits the mouths of healthy people. Pulmonary infection is thought to arise from inhalation of oral material while dental disease and general debility are regarded as predisposing factors. I In one of our three cases, there was direct evidence of inhaled foreign material. Moreover, it is interesting that in all three cases the right lung was involved in a segmental distribution that accords with aspiration. Actinomycosis usually responds to treatment with c o m m o n antibiotics and most cases recover well with prolonged therapy. 2 Actinomycosis is more often a cervico-facial or abdominal, t h a n a thoracic infection. There was pulm o n a r y involvement in only one of 36 cases of actinomycosis reported in the U.K. in 19701 and in three of 43 cases reported in 1976. 3 The classical appearance of chronically draining sinuses is now hardly ever seen in this country, presumably because of the widespread use of antibiotics. The diagnostic difficulty of pulmonary actinomycosis arises from a lack of specific findings. The clinical symptoms are c o m m o n to m a n y chest diseases and are, most often, cough with sputum, chest pain, weight loss and haemoptysis. 4 The presence of Actinomyces in the sputum is unhelpful because the organism is a c o m m o n oral commensal. Chest radiographic appearances are also variable. Flynn and Felson, 5 in a review of 15 cases in 1970, reported pleural effusions, empyema and pleural thickening as the most frequent findings. Masses, infiltrates, with and without cavitation, as well as fibrotic lesions were often seen also. In their conclusion,
they suggested several features which should arouse suspicion of actinomycosis. These are: extension of pulmonary lesions through the thoracic wall, pulmonary lesions associated with periostitis and destruction of ribs as well as extension of lesions across interlobar fissures. Frank and Strickland, ~ however, in a review of six cases in 1974, found radiographic evidence of rib involvement in only one case and of pleural disease in two cases. CT is helpful in demonstrating the extent and relationship of pulmonary and chest wall disease but has no specific diagnostic features in this context. 7 The organism m a y be recovered by means of percutaneous needle biopsy and transbronchial or open lung biopsy but the diagnosis is often made histologically by Gram-staining. The abcesses are typically surrounded by granulation tissue with a variable degree of fibrosis. They contain masses of polymorphonuclear leucocytes with which so-called 'sulphur granules' m a y be associated. The organisms can usually be seen in the centre of the granules. 8 A positive biopsy will prevent the patient from undergoing unnecessary surgery so that biopsy should always be considered in the investigation of a solitary or atypical pulmonary lesion. Recently, there have been several reports of actinomycosis presenting as endobronchial lesions during bronchoscopy. A diagnosis was then made from bronchial biopsy material and washings. 9' 10 The masquerading of pulmonary actinomycosis as pulmonary malignant neoplasia has been recognised for m a n y years, n In view of the declining incidence of the disease, however, the cases presented here serve as a reminder of the diagnostic difficulty that pulmonary actinomycosis m a y present. Such a diagnosis should always be borne in mind in the differential diagnosis of thoratic malignant neoplasia, particularly in younger adults in w h o m malignant neoplasia is less common. Preoperative recognition in our three patients would have prevented thoracotomy and, in one case, quite extensive resection of the chest wall.
References 1 Brown JR. Human Actinomycosis: a study of 181 subjects. Human Pathol 1973; 4: 319-330. 2 Slade PR, Slesser BV, Southgate J. Thoracic actinomycosis. Thorax 1973; 28: 73-85. 3 Epidemiology.Br MedJ 1977; 1: 1037. 4 Bates M, Cruickshank G. Thoracic actinomycosis.Thorax 1957; 12: 99-123. 5 Flynn MW, Felson B. The Roentgen manifestations of thoracic actinomycosis. Am J Radiol 1970; 110: 707-716. 6 Frank P, Strieldand B. Pulmonary actinomycosis.BrJ Radiol 1974; 47: 373-378. 7 Webb W, Sagel SS. Actinomycosis involving the chest wall: CT
H. M. Shannon et aL findings. Am J Radiol 1982; 139: 1007-1009. 8 Fraser RG, Pare JAP. In: Diagnosis of disease of the chest, Philadelphia: Saunders, 1989; 1022-1028. 9 Lau K. Bndobronchial actinomycosis mimicking pulmonary neoplasm. Thorax 1992; 47: 664-665.
169
10 Ariel I, Breuer R, Kamal NS, Ben-Dov I, Mogie P, Rosemann E. Endobronchial actinomycosis simulating bronchogenic carcinoma. Chest 1991; 99: 493-495, 11 Prather JR, Eastridge CE, Hughes FA, McCaugan JJ. Actinomycosis of the thorax. Ann Thorac Surg 1970; 9: 307-312.