Tularemic pneumonia is often complicated by pleural involvement and effusion.1 The causative pathogen, Francisella tularensis, rarely has been cultured form pleural fluid.1 The microbiological diagnosis of tularemia relies mainly on serology.
A healthy 31 year old male, construction worker, was admitted to an outlying emergency room for the sudden onset of fever, shaking chills, productive cough and dyspnea. A Chest Roentgenogram documented right middle and lower lobes consolidations with right pleural effusion. Diagnostic thoracentesis yielded a sero-sanguineous effusion with 1313 UI LDH, 2.9 protein, 48 glucose, and a negative Gram stain. Pleural fluid cultures were sent. He was initially treated for community acquired pneumonia. but increasing oxygen requirements resulted in broadening of antimicrobials to include imipenem, azithromycin, moxifloxacin and fluconazole and he was transferred to Cooper University Hospital.Physical exam upon arrival revealed a tachypneic young man on 100% oxygen non re-breather. No cervical or inguinal lymphadenothy were appreciated, and there were no skin lesions or rashes noted. Diffuse rhonchi were heard over bilateral lung fields. The remainder of physical examination was unremarkable. A chest CT scan showed right apical area necrosis, left lower lobe consolidation and moderate left pleural effusion. A repeat thoracentesis yielded similar results to the initial thoracocentesis.Antibiotics were changed to levofloxacin and vancomycin. His clinical condition markedly improved and after 48 hours supplemental oxygen was no longer need. He was discharged on P.O levafloxacin. Three days after discharge, the pleural fluid from the initial right sided thoracentesis grew Francisella tularensis. Indentity of the isolate was confirmed by PCR by the New Jersey State Department of Health Laboratory. Treatment was switched to doxycycline for two weeks, he then completed an additional three weeks of levafloxacin due to Doxycycline induced GI Discomfort.
This case illustrates pneumonic tularemia; one of the six distinct clinical syndromes of Francisella tularensis infection. Pneumonic tularemia refers to an illness with an initial presentation dominated by pulmonary infection. Two clinical forms are recognized. The primary form occurs by direct inhalation of aerosolized Francisella tularensis. It includes many of the most fulminate cases encountered.2 The secondary form can complicate any of the other clinical syndromes, mainly typhoidal and ulceroglandular disease.2 and is believed to occur by hematogenous spread . Our patient may have become infected by inhaling aerosolized Francisella tularensis while clearing his work site with a power mower.The pleural effusion in pleuropulmonary tularemia is described as turbid or sero-sanguineous exudate with a predominance of lymphocytes or neutrophils and a high Adenosine Deaminase level.1 Pleural granulomas can be found on pleural biopsy specimens.4 Findings that mimic tuberculous pleurisy.1,4Francisella tularensis has rarely been cultured from pleural fluid.1 Culture of Francisella tularensis is not routinely performed due to special media requirements and potential hazard to laboratory personnel. When growth is suspected, a reference laboratory should be consulted for safe handling and confirmation by detection of DNA encoding for a 17-kD lipoprotein of Francisella tularensis, as occurred in our case.2.
Pneumonic Tularemia can cause pleural effusion. When suspected, Adenosine deaminase level and culture for Francisella tularensis should be included in the analysis of the pleural fluid specimen.
Anthony Perella, None.