CC: Shortness of breath, Cough
ID: This is a 20 yo female with no significant past medical history who presents with cough and shortness of breath for 2 weeks. Three days into her course, she was diagnosed with pneumonia at an outside emergency department and was discharged home with a course of amoxicillin. However, her symptoms worsened despite 6 days of antibiotics. New symptoms appeared a few days prior to admission including including pleuritic chest pain, worsening shortness of breath when supine, chills as well as fevers. Of note, patient is from Mexico and moved to the United States at 6 years-old. Her family frequently visits her from Mexico, the last visit occurring one month ago. On exam patient is febrile to 39.8 degrees Celsius, tachycardic to 130 with significant findings of decrease breath sounds on the left side in addition to decrease fremitus and dullness to percussion. CXR obtained showed a large effusion that layered out on lateral decubitus position. Pleural fluid returned consistent with a lymphocyte predominant, exudative process. Cytology was sent twice which showed no atypical cells but an elevated adenosine deaminase was detected making Pleural Tuberculosis highest on the differential. Given the suspicion for extra pulmonary TB, a pleural biopsy was pursued and patient was empirically started on RIPE therapy. Pleural biopsy showed necrotizing granulomas but AFB stain negative. Four weeks later, cultures from pleural fluid and pleural biopsy grew out Mycobacterium Tuberculosis.
Pleural Fluid Analysis:
Morning Report Pearls:
When an exudative effusion is diagnosed using Light’s Criteria, it is important to check that it is not a pseudoexudate which can occur due to inherent errors in using protein and LDH pleural/serum ratios but particularly in the setting of diuretic use. If pleural albumin – serum albumin >1.2 then this is consistent with a pseudoexudate and the fluid likely represents a transudative effusion rather then exudative. Pleural fluid total protein – serum total protein >3.1 can also be used instead of the albumin gradient.
Nucleated cell counts are useful in differentiating etiologies:
It is important to define if a parapneumonic effusion in a non-resolving pneumonia is complicated or an empyema. Luckily with our patient, this was not the case. However if diagnosed with either, management changes as the patient requires drainage of the effusion in addition to antibiotic therapy:
Given this patient had a true lymphocytic exudative effusion in the setting of tuberculosis risk factors, an adenosine deaminase was correctly sent. It is important to remember the utility of the various TB studies: