1991, The British Journal of Radiology, 64, 175-176
Case of the month An unusual case of pneumonia By R. Chaudhuri, FRCR Queen Mary's Hospital, Roehampton, London SW15 (Received September 1988) Keywords: Chest radiography
A 41-year-old European man presented with a 4-week history of increasing dyspnoea, left pleuritic chest pain, productive cough and 7 kg weight loss. He had smoked 60-70 cigarettes per day for many years, and he drank 3 pints of beer daily. He had had a myocardial infarction 5 years before, and had paranoid schizophrenia, well controlled on monthly flupenthixol injections. On examination, he was pyrexial with signs of consolidation at the left lung base. There was no adenopathy. His fingers were heavily nicotine stained and his dental hygiene very poor. Investigations revealed a mild anaemia, elevated white blood cell count and ESR 100 mm/h. An initial chest radiograph showed a left basal effusion loculated posteriorly (Fig. 1). What is the differential diagnosis at this stage? He was discharged on trimethoprim, with some weight gain, erythrocyte sedimentation rate (ESR) 32 mm/h, but little resolution on chest radiography. Two months later he had developed a woody indurated mass over the left anterior ribs, with a central discharging sinus. He had again lost 3 kg, and the ESR had risen. Sputums were negative for acid-fast bacilli and malignant cells. Bronchoscopy was normal and bronchial biopsy and washings were unhelpful. No pleural fluid could be aspirated.
The chest radiograph at this stage is shown (Fig. 2). How would you modify the differential diagnosis and how could the diagnosis be confirmed?
J
(a) ' • ' * .
Current address: Department of Radiology, Guy's Hospital, London SE1 9RT.
Figure 1. Chest radiograph on presentation. Vol. 64, No. 758
Figure 2. Chest radiographs after antibiotic treatment.
175
Case of the month
Figure 3. Enhanced CT scan through mediastinum at the level of the main pulmonary artery, showing lower extent of mass. At presentation the differential diagnosis was of infection, including atypical pneumonias and tuberculosis, carcinoma of the bronchus with metastatic effusion or possibly pulmonary infarction or a collagen disorder. The second chest radiograph shows considerable pleural thickening over the left lower lobe with a solid looking mass posteriorly, with no associated rib involvement. In view of his history, the differential diagnosis was modified to either a neoplastic cause (including bronchial carcinoma with cutaneous metastasis, lymphoma or malignant mesothelioma) or a chronic infective cause (including tuberculosis, actinomycosis and fungal disease). A diagnosis was made by gram-staining of aspirated sinus fluid and biopsy of the chest wall lesion, which revealed a 5 cm subcutaneous abscess. Pathognomonic sulphur granules of Actinomyces Israeli were identified. The patient was treated with high-dose tetracycline, continuously. One year later, the chest radiograph was almost completely clear. Four years later, however, he developed an anterior mediastinal mass. Computed tomographic (CT) scan showed a thymic mass (Fig. 3), which was found to be a thymic cyst, containing foci of neoplastic tissue in the lining. The patient remains well 1 year after surgery. Discussion Since the advent of antibiotics, actinomycosis has become increasingly uncommon. Actinomyces israeli is a saprophytic anaerobe existing freely in the mouth and upper respiratory tract. The usual source for thoracic disease is from carious teeth, infected gums, periodontal membranes and tonsils. Diagnosis depends on finding the sulphur granule which is a mycelium surrounded by radiating club-shaped rods. It produces proteolytic enzymes allowing penetration across usual anatomical boundaries. Thoracic actinomycosis constitutes 15% of all cases. 176
It is a wasting disease. Progressive lung infiltration and pleural involvement with fistula formation are common. Radiographic features in the chest, documented by Flynn and Felson (1970), are of a mass lesion, chronic alveolar infiltrate, pulmonary fibrosis, cavitation, pleural effusion or empyema. Spread is directly through the chest wall with associated wavy periostitis or frank rib destruction, or extension of pulmonary lesions across interlobar fissures. Dermal lesions may be local or peripheral (Webb et al, 1978). Sinus tracts on the chest wall may fistulize into the lung, pleural cavity, trachea, oesophagus or abdomen. Mediastinal widening, spinal involvement, pulmonary osteoarthropathy and erosion into blood vessels with haematogenous dissemination have also been described. Rarely, congestive heart failure, constrictive pericarditis, endocarditis and peripheral effusions occur secondary to direct spread from the pleura. The radiological features of pulmonary actinomycosis are largely non-specific. Bates and Cruickshank (1957) suggested that periostitis of several adjacent ribs in the absence of empyema was the only pathognomonic finding, a view supported by Flynn and Felson (1970). However, only one of a series of six described by Frank and Strickland (1974) showed this sign, while none of six in Slade's series (Slade et al, 1973) or our patient showed periostitis. A misdiagnosis of carcinoma of the bronchus or tuberculosis, with subsequent lobectomy or pneumonectomy has been well documented (Bates & Cruickshank, 1957; Slade et al, 1973). These studies have shown both bronchial carcinoma and pulmonary tuberculosis can co-exist with actinomycosis. However, association with a thymoma has not been described. In summary, inappropriate antibacterial therapy or surgery may be prevented if pulmonary actinomycosis is considered at an early stage in unusually presenting pneumonias. The most valuable, but not the most frequent, radiological clues are a wavy periosteal reaction of the ribs and extension of lesions across interlobar fissures. Potentially more serious superadded or causally related complications, such as TB or malignancy and perhaps also thymoma, should be remembered. Acknowledgments I would like to thank Dr P. Frank and Dr D. G. Leaver for their advice and permission to publish this case. References BATES, M. & CRUICKSHANK, G., 1957. Thoracic actinomycosis. Thorax, 12, 99-124. FLYNN,
M.
W.
&
FELSON,
B.,
1970.
The
roentgen
manifestations of thoracic actinomycosis. American Journal of Roentgenology, 110, 707-716. FRANK, P. & STRICKLAND, B., 1974. Pulmonary actinomycosis.
British Journal of Radiology, 47, 373-378. SLADE, P., SLESSER, B. V. & SOUTHGATE, J., 1978. Thoracic
actinomycosis. Thorax, 28, 73-85. WEBB, A. K., HOWELL, R. & HICKMAN, J. A., 1978. Thoracic
actinomycosis presenting with peripheral Thorax, 33, 818-819.
skin
lesions.
The British Journal of Radiology, February 1991
Case of the month An unusual case of pneumonia By R. Chaudhuri, FRCR Queen Mary's Hospital, Roehampton, London SW15 (Received September 1988) Keywords: Chest radiography
A 41-year-old European man presented with a 4-week history of increasing dyspnoea, left pleuritic chest pain, productive cough and 7 kg weight loss. He had smoked 60-70 cigarettes per day for many years, and he drank 3 pints of beer daily. He had had a myocardial infarction 5 years before, and had paranoid schizophrenia, well controlled on monthly flupenthixol injections. On examination, he was pyrexial with signs of consolidation at the left lung base. There was no adenopathy. His fingers were heavily nicotine stained and his dental hygiene very poor. Investigations revealed a mild anaemia, elevated white blood cell count and ESR 100 mm/h. An initial chest radiograph showed a left basal effusion loculated posteriorly (Fig. 1). What is the differential diagnosis at this stage? He was discharged on trimethoprim, with some weight gain, erythrocyte sedimentation rate (ESR) 32 mm/h, but little resolution on chest radiography. Two months later he had developed a woody indurated mass over the left anterior ribs, with a central discharging sinus. He had again lost 3 kg, and the ESR had risen. Sputums were negative for acid-fast bacilli and malignant cells. Bronchoscopy was normal and bronchial biopsy and washings were unhelpful. No pleural fluid could be aspirated.
The chest radiograph at this stage is shown (Fig. 2). How would you modify the differential diagnosis and how could the diagnosis be confirmed?
J
(a) ' • ' * .
Current address: Department of Radiology, Guy's Hospital, London SE1 9RT.
Figure 1. Chest radiograph on presentation. Vol. 64, No. 758
Figure 2. Chest radiographs after antibiotic treatment.
175
Case of the month
Figure 3. Enhanced CT scan through mediastinum at the level of the main pulmonary artery, showing lower extent of mass. At presentation the differential diagnosis was of infection, including atypical pneumonias and tuberculosis, carcinoma of the bronchus with metastatic effusion or possibly pulmonary infarction or a collagen disorder. The second chest radiograph shows considerable pleural thickening over the left lower lobe with a solid looking mass posteriorly, with no associated rib involvement. In view of his history, the differential diagnosis was modified to either a neoplastic cause (including bronchial carcinoma with cutaneous metastasis, lymphoma or malignant mesothelioma) or a chronic infective cause (including tuberculosis, actinomycosis and fungal disease). A diagnosis was made by gram-staining of aspirated sinus fluid and biopsy of the chest wall lesion, which revealed a 5 cm subcutaneous abscess. Pathognomonic sulphur granules of Actinomyces Israeli were identified. The patient was treated with high-dose tetracycline, continuously. One year later, the chest radiograph was almost completely clear. Four years later, however, he developed an anterior mediastinal mass. Computed tomographic (CT) scan showed a thymic mass (Fig. 3), which was found to be a thymic cyst, containing foci of neoplastic tissue in the lining. The patient remains well 1 year after surgery. Discussion Since the advent of antibiotics, actinomycosis has become increasingly uncommon. Actinomyces israeli is a saprophytic anaerobe existing freely in the mouth and upper respiratory tract. The usual source for thoracic disease is from carious teeth, infected gums, periodontal membranes and tonsils. Diagnosis depends on finding the sulphur granule which is a mycelium surrounded by radiating club-shaped rods. It produces proteolytic enzymes allowing penetration across usual anatomical boundaries. Thoracic actinomycosis constitutes 15% of all cases. 176
It is a wasting disease. Progressive lung infiltration and pleural involvement with fistula formation are common. Radiographic features in the chest, documented by Flynn and Felson (1970), are of a mass lesion, chronic alveolar infiltrate, pulmonary fibrosis, cavitation, pleural effusion or empyema. Spread is directly through the chest wall with associated wavy periostitis or frank rib destruction, or extension of pulmonary lesions across interlobar fissures. Dermal lesions may be local or peripheral (Webb et al, 1978). Sinus tracts on the chest wall may fistulize into the lung, pleural cavity, trachea, oesophagus or abdomen. Mediastinal widening, spinal involvement, pulmonary osteoarthropathy and erosion into blood vessels with haematogenous dissemination have also been described. Rarely, congestive heart failure, constrictive pericarditis, endocarditis and peripheral effusions occur secondary to direct spread from the pleura. The radiological features of pulmonary actinomycosis are largely non-specific. Bates and Cruickshank (1957) suggested that periostitis of several adjacent ribs in the absence of empyema was the only pathognomonic finding, a view supported by Flynn and Felson (1970). However, only one of a series of six described by Frank and Strickland (1974) showed this sign, while none of six in Slade's series (Slade et al, 1973) or our patient showed periostitis. A misdiagnosis of carcinoma of the bronchus or tuberculosis, with subsequent lobectomy or pneumonectomy has been well documented (Bates & Cruickshank, 1957; Slade et al, 1973). These studies have shown both bronchial carcinoma and pulmonary tuberculosis can co-exist with actinomycosis. However, association with a thymoma has not been described. In summary, inappropriate antibacterial therapy or surgery may be prevented if pulmonary actinomycosis is considered at an early stage in unusually presenting pneumonias. The most valuable, but not the most frequent, radiological clues are a wavy periosteal reaction of the ribs and extension of lesions across interlobar fissures. Potentially more serious superadded or causally related complications, such as TB or malignancy and perhaps also thymoma, should be remembered. Acknowledgments I would like to thank Dr P. Frank and Dr D. G. Leaver for their advice and permission to publish this case. References BATES, M. & CRUICKSHANK, G., 1957. Thoracic actinomycosis. Thorax, 12, 99-124. FLYNN,
M.
W.
&
FELSON,
B.,
1970.
The
roentgen
manifestations of thoracic actinomycosis. American Journal of Roentgenology, 110, 707-716. FRANK, P. & STRICKLAND, B., 1974. Pulmonary actinomycosis.
British Journal of Radiology, 47, 373-378. SLADE, P., SLESSER, B. V. & SOUTHGATE, J., 1978. Thoracic
actinomycosis. Thorax, 28, 73-85. WEBB, A. K., HOWELL, R. & HICKMAN, J. A., 1978. Thoracic
actinomycosis presenting with peripheral Thorax, 33, 818-819.
skin
lesions.
The British Journal of Radiology, February 1991
