A 79-year-old man, allergic to beta-lactams with a personal history of corticodependent COPD with several flare-ups a year and on treatment with home oxygen and bronchodilators at full doses (NYHA functional status III-IV). He came to the hospital with a 3-day history of cough with purulent expectoration, increased respiratory distress and worsening level of consciousness. Physical examination revealed fever of 38°C, central and peripheral cyanosis, increased jugular venous pressure, tachycardia at 120 bpm, prolonged expiratory time, wheezing and expiratory rhonchi in both lung fields, especially in the right lung. In the abdomen, painful hepatomegaly and oedema in both legs. Chest X-ray showed increased density in the right lower lobe, with poorly defined borders. The haemogram showed 22,970 leukocytes/mm3 (93N, 3.4L), Hb 13 g/dl, HCT 37%, MCV 90 fl, PLQ 235,000/mm3. Blood gas results were pH 7.45, pO257, pCO2 36.4, HCO3 25.9, SatO2 90%. Blood and sputum cultures were performed on general media (blood and chocolate agar, Biomerieux®) and for mycobacterial studies (Bactec 960 MGIT (Mycobacterial Growth Indicator Tube) and Lowenstein (Becton Dickinson®)}. Gram and Ziehl stains of sputum did not provide diagnostic guidance. Sputum culture at 24 hours (intermediate quality, > 25 leukocytes 10-25 epithelial cells) showed only the usual respiratory tract flora. Empirical treatment was started with Levofloxacin iv. (500 mg/day), Vancomycin e.v. (1 g/12 h) and Tobacco (1 g/12 h). (1 g/12 h) and Tobramycin e.v. (200 mg/12 h). (200 mg/12 h). The patient developed a progressive clinical (hypotension, dyspnoea and fever) and analytical worsening (haemogram then showed 40,000 leukocytes/mm3), and died on the fourth day of admission.

On the same day of death, a positive blood culture and sputum culture were observed, both in specific medium for mycobacteria (MGIT). Ziehl's staining of both showed tangles of branched Ziehl's positive bacilli. From MGIT broth to Mueller-Hinton (Biomerieux®) and Lowenstein medium, dry colonies grew after 24 hours, initially whitish, but after 48 hours, they turned salmon-like, with a gypsum-like texture. The problem strain was sent to the National Microbiology Centre in Majadahonda. There, the 16S rDNA sequence of the microorganism was amplified by PCR and, with 100% homology, it was identified as Nocardia otitidiscaviarum.