Extremely Increased Serum Carbohydrate Antigen 19-9 Levels Caused by New or Resistant Infections to Previous Antibiotics in Chronic Lung Diseases
In May 2010, a 72-year-old female came to Chungnam National University Hospital for cough and sputum. She had been diagnosed with bronchiectasis 6 years before. Chest auscultation revealed a moderate inspiratory crackle sound in both lower lung fields. Her blood examination showed a hemoglobin level of 11.2 g/dL, white blood cell count of 7.9×103/mL, and platelet count of 427×103/µL and C-reactive protein of 4.3 mg/dL. Electrolytes, measures of renal function, and liver enzymes were within normal limits. On that occasion, increased serum levels of CA 19-9 were noted (range, 1,453 U/mL; reference range, <37 U/mL). An abdominal computed tomography (CT) scan, esophagogastroduodenoscopy and colonoscopy were performed and showed no abnormal findings. Compared to 6 years before, chest radiography revealed subtle increased interstitial densities and CT revealed aggravated bronchial dilatation surrounded by small nodules on both lung fields (). With bronchoscopy, moderate amount of mucinous sputum was found and Mycobacterium intracellulare was identified in bronchoscopic washing. In August 2010, anti-Mycobacterium avium complex (MAC) treatment was initiated with clarithromycin (1 g/day), rifampicin (450 mg/day), ethambutol (800 mg/day). Anti-MAC treatment was continued and her symptoms including cough and sputum were gradually improved. In October 2010, the serum CA 19-9 levels decreased to 357 U/mL () and the chest CT revealed decreased nodularities ().\nIn June 2011, she was re-admitted for increased cough and sputum without any other respiratory symptom including fever or dyspnea. The simple chest radiograph showed mild increased opacities at especially right lower lobe (). Laboratory tests determined that the serum CA 19-9 levels increased to 5,300 U/mL (). Large amount of sputum was drained from right upper lobe in bronchoscopy. The sputum CA 19-9 levels were 148 U/mL and sputum cultures from broncholaveloar lavage fluid (BALF) were positive for Pseudomonas aeruginosa. After 2 weeks of antibiotic treatment with an anti-pseudomonal agent, her clinical symptoms were improved and she was discharged. In August 2011, the serum CA 19-9 levels decreased to 534 U/mL ().\nIn June 2012, she was re-admitted for increased sputum unaccompanied significant chest radiographic changes, and the CT scan revealed aggravated bilateral nodularities (). At that time, the serum CA 19-9 levels were 1,006 U/mL (), an acid-fast bacteria stain of the sputum was positive, and polymerase chain reaction for M. tubuerculosis was negative. Clarithromycin resistance was confirmed by drug susceptibility test and she was transferred to another hospital.