Diagnostic Assessment & Therapeutic Intervention
Due to fever, dyspnea, and an SPO2 below 90%, a Computed Tomography (CT) was performed. The chest CT showed moderate pleural effusion and bilateral emphysema in the apex of the lungs and cardiomegaly. Pelvic and abdominal ultrasounds were normal. Because of dyspnea, tachycardia elevated D-dimer, and SpO2 of less than 90%, we decided to take CT angiography for pulmonary thromboembolism (PTE). CT angiography showed PTE, moderate pleural effusion in the right lung compatible with empyema, and a blurred wedge in the left upper lobe (LUL). We put the patient under anticoagulation therapy with warfarin, after PTE was diagnosed, and based on the loculated pleural fluid in the CT scan, empyema pattern, and the patient’s fever, the effusion was tapped, and a chest tube was placed. The patient’s pleural fluid was analyzed, which was exudative with Alb=900, Pro=2400, LDH=1184, RBC=50, WBC=3400, Glucose=80, and negative culture.
The lung field was found to have a septic embolism pattern, which led to an echocardiogram. Upon echocardiography, small vegetation was detected; therefore, a transthoracic echocardiogram (TTE) was conducted to confirm. TTE showed severe tricuspid valve damage, 8 millimeter vegetation in place, increased pulmonary artery pressure (PAP= 40), and ejection fraction(EF)=45%, confirming the vegetation on the atrial side of the tricuspid valve.
According to the findings, the first diagnosis was right-side endocarditis, which led to septic embolism, so we started empiric antibiotic therapy with vancomycin plus ceftriaxone. After two weeks of constant fever despite broad-spectrum antibiotic therapy and pleural effusion drainage, we changed the antibiotic regimen to vancomycin plus meropenem, and, re-evaluated our diagnosis by taking a detailed history, re-sending blood cultures, which were negative 3 times, performing abdominal ultrasound and investigating the possible causes of culture-negative endocarditis including Q fever, bartonella, and brucellosis, according to the history of staying in the camp. The serology and blood PCRs were sent to the laboratory of the Pasteur Institute of Iran. The PCR and serology for Q-fever were negative. serology wright and 2-ME test for brucellosis were negative, but a serology test confirmed for Bartonella henselae with a 1: 2048 titer.11the kit used was Bartonella IFA IgG.
In the meantime, we changed the patient’s drug regimen to doxycycline (100 mg twice daily), instead of aminoglycosides, plus rifampin (300mg twice daily), due to the high level of creatinine (3-3.3 mg/dL), and warfarin was switched to enoxaparin due to rifampin and warfarin drug interactions and patient noncompliance.
After 72 hours he responded to this drug combination significantly; fever, tachycardia, and dyspnea improved, creatinine levels decreased and the pleural fluid test result was negative for Bartonella. After two weeks, rifampin was discontinued, but he received an extended course of doxycycline monotherapy. Also, due to severe tricuspid valve insufficiency, he underwent medical treatment, but because of his addiction, the cardiac surgery service did not recommend him for valvoplasty. A summary of the clinical practice of the patient is shown in Figure 1.