Pandemic Influenza (H1N1) and Mycobacterium tuberculosis Co-infection
A 45-year-old man visited the ED on December, 2009 because of fever and cough for one day and one incident of hemoptysis estimated at about 400 mL. He had a history of pulmonary tuberculosis diagnosed in 2007 and reported a complete recovery after treatment. A physical examination upon admission revealed a high body temperature (38.1℃) and increased pulse rate (105/min), while his breath sounds were clear. Oxygen saturation was 97% under an oxygen supply of 2 L/min via nasal cannula. Laboratory findings were as follows: WBC, 7,110/mm3; neutrophils, 80.8%; lymphocytes, 650/mm3 (9.1%); and CRP, 6.69 mg/L. A chest X-ray showed multiple small nodules and patchy consolidation predominantly in the left lung field, and chest CT revealed a cavitary nodule and tree-in-bud appearance on the left upper lung and left lingular segment, with ground glass opacities due to aspirated blood on the left lower lung suggesting tuberculosis reactivation (). However, pH1N1 RT-PCR was positive for a nasopharyngeal swab specimen, and a conventional dose of oral oseltamivir was prescribed. Fever spiking was improved after starting oseltamivir, but it remained to lower degree for 4 days. Repetitive sputum AFB smears were negative, while MTB complex-specific PCR was positive. Due to suspected active pulmonary tuberculosis, isoniazid, rifampin, ethambutol and pyrazinamide were prescribed on HOD 4. Fever subsided from the next day of starting anti-tuberculosis medication, and respiratory symptoms gradually improved, so the patient was discharged on HOD 6. Three weeks after collection, a sputum culture revealed growth of MTB.