Teaching Case

A 29-year-old female presented to the hospital with a 5-weeks history of chest pain, fever, night-sweats, and weight-loss. She moved to the UK some years ago, from an endemic area for tuberculosis (TB). Initial investigations suggested diagnosis of myopericarditis. However, as patient didn't respond to primary management, more investigations were undertaken.

Initial CXR was normal (Fig.1). Second CXR showed subtle loss of left cardiac silhouette (Fig.2).

She had a CT Pulmonary Angiogram (CTPA), which revealed no pulmonary embolism, but showed paracardiac mass along the base and apex of the heart measuring 8.9x6.2cm, iso-attenuating to myocardium on the pulmonary arterial phase (Fig.3) along with left-axillary lymphadenopathy (Fig.4). Possibility of a paracardiac tumour considered, however, no nodule was seen within the lung-parenchyma. Pleural spaces were clear.

A CT chest abdomen pelvis was performed the next day in the portal venous phase (Fig.5). In this phase, the visualised lower-thorax better delineated the mass which was pericardial, primarily cystic, multi-loculated and demonstrated avid pericardial enhancement. Histology study of biopsies of lymph nodes indicated caseous granuloma.

A presumed diagnosis of pericardial TB was made and treatment was commenced.
The patient had a thoracic MRI for follow up, which demonstrated substantial resolution in pericardial changes (Fig.6 and 7).

Tuberculosis pericarditis is seen in nearly 1-2% of patients with pulmonary tuberculosis [1], the diagnosis of which is usually delayed or missed. It can occur by spreading of an infection from the lung or tracheobronchial tract, from infected close structures such as adjacent lymph nodes, spine, sternum, or via miliary spread. In many patients, tuberculosis pericarditis may present in the absence of a primary focus of tuberculosis elsewhere.
Tuberculosis pericarditis usually presents non-specific symptoms such as cough, dyspnoea, chest pain, night sweats and orthopnea [2]. However, it rarely shows up with symptoms of constrictive pericarditis in late stages.
On clinical examination, signs would include high temperature, tachycardia, a pericardial friction rub and distant heart sounds on auscultation, as well as features of cardiac failure (raised jugular venous pressure, hepatomegaly, ascites, and peripheral oedema).
Important complications of tuberculosis pericarditis include constrictive pericarditis, effusive pericarditis and cardiac tamponade [2].
In teaching point of view, tuberculosis pericarditis should be considered as one of the differential diagnosis in patients with non-self-limiting pericarditis, particularly in patients with previous exposure to TB [3]. The diagnosis can be made by detection of Acid Fast Bacilli (AFB) in pericardial fluid and/or detection of tubercle bacilli or caseous granuloma on pericardial histology [4]. Presence of TB elsewhere in the body, lymphocytic pericardial exudate and elevated adenosine deaminase (ADA) level will make the diagnosis of tuberculosis pericarditis more likely.
Initial investigations for tuberculosis pericarditis consist of:
* ECG: commonly shows non-specific ST segment changes.
* CXR: Looking for evidence of pulmonary TB (present in 32-72% of cases), evidence of cardiomegaly (seen in 90% of patients) and also presence of pericardial calcification in chronic cases (4, 5).
* Evaluation of sputum for acid-fast bacilli (AFB) smear and culture (3).
The following tests might also be required in order to make diagnosis:
* Trans-thoracic echocardiogram
* Computed Tomography /Magnetic Resonance Imaging
* A tuberculin skin test (TST) and/or interferon gamma release assay (IGRA)
* Pericardiocentesis and evaluation of pericardial fluid for cell count, protein concentration, lactate dehydrogenase concentration, acid-fast smear/culture, Gram stain and bacterial culture, adenosine deaminase concentration, and cytology.
* Pericardial biopsy especially in non-endemic areas for TB, for patients whose symptoms lasted more than 3 months and definitive diagnosis has not been achieved through use of the above tests.
Treatment includes:
* Anti-tuberculosis medication.
* Corticosteroids mainly in patients with high risk of progression to constrictive pericarditis.
* Pericardiectomy in patients with persistent constrictive pericarditis not responding to anti-tuberculosis medication.