A 68 year old Caucasian male initially presented to outpatient infectious disease clinic with a chief complaint of intermittent fever for 3-4 weeks. The fever was associated with chills, night sweats, nausea, headaches, and a fifteen pound unintentional weight loss. His past medical history was significant for recurrent small bowel obstruction with multiple previous abdominal surgeries, chronic watery diarrhea, factor V Leiden deficiency, recurrent urinary tract infections, MRSA infection, and type II diabetes. Patient had a trans-psoas Hickman catheter initially placed about 3 years ago for total parenteral nutrition (TPN) and hydration purposes. The catheter was replaced about 2 months ago prior to presentation due to malfunctioning and retraction issues. Vital signs included blood pressure: 98/50 mm-hg, pulse 70 beats per minute, respiratory rate of 18 per minute and temperature of 98 F. There was no focus of infection on physical examination, including the port site. He denied recent travel outside Illinois, had a pet cat at home, and used tap water for drinking. His white cell count was within normal limits, and ESR was elevated 55 (normal limit: 0-15 mm/h).
Work up including blood cultures, Quantiferon gold test, sputum for acid fast bacilli (AFB), and a trans-esophageal echocardiography (TEE) was ordered. Two sets of blood cultures 2 weeks apart were positive for Mycobacterium neoaurum. Work up for histoplasmosis, and human immunodeficiency virus (HIV) was unremarkable. Tagged white blood cell (WBC) scan showed increased uptake in bilateral lungs consistent with pneumonitis. Computed tomography (CT) chest was ordered due to new onset cough which showed numerous bilateral small non calcified centrilobular nodules within upper and lower lobes, consistent with pneumonitis (Fig. 1). Interferon-Gamma Release Assay (IGRA) for TB (QuantiFERON -TB Gold In-Tube test, Qiagen, NV, Venlo, Netherlands) was also positive. Transesophageal echocardiogram (TEE) showed no vegetation or abnormalities. The Hickman catheter was removed, and catheter tip was sent for AFB cultures. A temporary right femoral central venous catheter was placed. The patient was started on intravenous (IV) cefoxitin 2 g 4 times daily, IV ciprofloxacin 500 mg twice daily, and oral doxycycline 100 mg twice daily. Blood cultures drawn after the initiation of anti-microbial drugs yielded no growth. Catheter tip culture showed growth of acid fast bacilli after 8 days. Culture susceptibilities showed the mycobacterium being susceptible to cefoxitin (MIC: 8 mcg/mL), imipenem (MIC < = 2 mcg/mL), ciprofloxacin (MIC: 0.25 mcg/mL), moxifloxacin (MIC < = 0.25 mcg/mL), amikacin (MIC< = 1 mcg/mL), doxycycline (MIC: 1 mcg/mL), trimethoprim-sulfamethoxazole (MIC: 0.5-9.5 mcg/mL), linezolid (MIC: 4 mcg/mL) and resistant to clarithromycin (MIC > 16 mcg/mL) and tobramycin (MIC: 16 mcg/mL).
The Hickman catheter was replaced a week after negative blood cultures. This 3-drug combination therapy was continued for 6 weeks and patient was transitioned to oral ciprofloxacin and doxycycline with plans for another 6 weeks of treatment. Treatment was stopped three weeks after transition (9 weeks total) as patient developed a diffuse macular erythematous rash on face and arms. CT chest obtained at the time of completion of treatment showed resolution of pulmonary nodules (Fig. 2). The patient was afebrile without further respiratory symptoms, fevers or chills at 6 months' follow up.
CT scan showing pulmonary nodules before treatment.