|Year : 2017 | Volume
| Issue : 1 | Page : 59
Air crescent sign in Pseudomonas aeruginosa pneumonia
Mansoor C Abdulla, Jemshad Alungal, Ram Narayan
Department of General Medicine, M.E.S. Medical College, Perinthalmanna, Kerala, India
|Date of Web Publication||29-Dec-2016|
Dr. Mansoor C Abdulla
Department of General Medicine, M.E.S. Medical College, Perinthalmanna, Kerala
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Abdulla MC, Alungal J, Narayan R. Air crescent sign in Pseudomonas aeruginosa pneumonia. J Assoc Chest Physicians 2017;5:59
A 55-year-old female was admitted with high-grade fever for 1 month and cough with scanty mucoid expectoration for 2 weeks. Examination showed severe pallor and bilateral coarse crepitations. Her hemoglobin was 4.1 g/dl (normocytic, normochromic), total white blood cell count 900/μl, platelet count 15,000/L, erythrocyte sedimentation rate 158 mm in 1 h. Peripheral smear showed pancytopenia and bone marrow revealed acute promyelocytic leukemia. Chest radiograph showed bilateral nonhomogenous opacities. Computed tomographic scan with contrast of the chest showed multiple nodular and patchy areas of consolidation in both lungs with lesions, showing air crescent sign (ACS) and cavitation [Figure 1]. Sputum culture grew Pseudomonas aeruginosa. She was treated with meropenem and amikacin, and chemotherapy was initiated.
|Figure 1: Computed tomographic scan with contrast of the chest showing multiple nodular and patchy areas of consolidation in both lungs with lesions showing air crescent sign and cavitation (a and b). Pseudomonas aeruginosa owth in MacConkey agar (c) and nutrient media (d)|
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The ACS, also called the meniscus or cap sign appears on radiographs or computed tomographic scans, describes the crescent of air that can be seen in invasive aspergillosis, semi-invasive aspergillosis, or other processes that cause pulmonary necrosis. The most common cause of the ACS is the fungus ball of angioinvasive aspergillosis. ACS is not specific for Aspergillus infection but can be seen in other conditions, such as cavitating neoplasm, intracavitary clot, and Wegener granulomatosis. We report a patient with acute promyelocytic leukemia who developed the ACS as a result of P. aeruginosa lung infection.
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