Medical Image of the Week: The Atoll Sign in Cryptogenic Organizing Pneumonia

Figure 1. Portable chest X-ray shows bilateral airspace opacities (yellow arrows) and possible trace pleural effusion (blue arrow).

Figure 2. Computed tomography of the chest showing (A) patchy ground glass opacity in the upper lungs with additional scattered circular areas of opacity in a reverse halo configuration (blue arrows, atoll sign) and (B) extensive bibasilar consolidation with air bronchograms.

A 54-year-old woman presented to the emergency department with cough and worsening shortness of breath. Her cough began approximately 1 month prior to presentation, at which time she was diagnosed with pneumonia by her primary care physician based on a chest X-ray at an outside institution. She tried and failed courses of azithromycin, doxycycline, and levofloxacin.

The patient had an oxygen saturation of 55% and hyperpyrexia to 101.7 F in the emergency department. An initial chest X-ray was suggestive of moderate multifocal pneumonia with pleural effusion (Figure 1). Subsequent chest computed tomography (CT; Figure 2) revealed findings consistent with cryptogenic organizing pneumonia (COP) including multiple upper lobe atoll signs. Infectious and autoimmune workups were negative and the patient experienced a rapid recovery with pulse steroids, providing further evidence for the diagnosis of COP.

CT is the best imaging modality for evaluation of potential COP. Features include consolidations and nodules, bronchial wall thickening or dilatation, and ground glass opacities (1). The atoll sign, consisting of a central ground glass opacity and surrounding consolidation which may also be called a reverse halo sign, is highly specific but not sensitive for organizing pneumonia (2). Definitive diagnosis requires lung biopsy, although the disease is often managed based on a presumptive diagnosis (3).

Joseph Frankl, BS¹ and Veronica A. Arteaga, MD²

¹University of Arizona College of Medicine and ²Department of Medical Imaging

Banner University Medical Center Tucson

Tucson, AZ USA

References

1. Lee JW, Lee KS, Lee HY, Chung MP, Yi CA, Kim TS, Chung MJ. Cryptogenic organizing pneumonia: serial high-resolution CT findings in 22 patients. AJR Am J Roentgenol. 2010 Oct;195(4):916-22. [CrossRef] [PubMed]
2. Davidsen JR, Madsen HD, Laursen CB. Reversed halo sign in cryptogenic organising pneumonia. BMJ Case Rep. 2016 Feb 8;2016. pii: bcr2015213779. [CrossRef] [PubMed]
3. Bradley B, Branley HM, Egan JJ, et al. Interstitial lung disease guideline: the British Thoracic Society in collaboration with the Thoracic Society of Australia and New Zealand and the Irish Thoracic Society. Thorax. 2008 Sep;63 Suppl 5:v1-58. [CrossRef] [PubMed]

Cite as: Frankl J, Artega VA. Medical image of the week: the atoll sign in cryptogenic organizing pneumonia. Southwest J Pulm Crit Care. 2017;15(2):92-3. doi: https://doi.org/10.13175/swjpcc100-17 PDF

Medical Image of the Week: Cannon V Waves

Figure 1. Video showing jugular venous distention to earlobes with cannon V waves.

A 66-year-old man experienced recurrent ascites of unknown etiology over six months. He had previously undergone a renal transplant secondary to complications of diabetes and hypertension and had known severe coronary artery disease. His most recent paracentesis revealed an albumin 1.6 g/dL (serum albumin 2.1) and a total protein of 3.8 g/dL. His adenosine deaminase was 11.6 U/L (normal <7.6 U/L), but repeated bacterial and mycobacterial ascites cultures were negative, as were a carcinoembryonic antigen assay and ascites cytology. Computerized tomography of the abdomen showed findings consistent with cirrhosis, but an extensive workup for common causes of cirrhosis was negative.

Physical exam showed jugular venous distention with prominent V waves and a holosystolic murmur at the left lower sternal border (Figure 1). Echocardiography showed a dilated right ventricle, moderate pulmonary and tricuspid regurgitation and an estimated right ventricular systolic pressure of 87 mm Hg. Cardiac catherization confirmed the presence of an elevated right ventricular pressure of 72/10 (22) mm Hg, an elevated pulmonary artery pressure of 75/27 (45) mm Hg and a left ventricular ejection fraction of 20-25%. The right atrial pressure was 20 and the pulmonary artery occlusion pressure was 22 mmHg.  A diagnosis of pulmonary hypertension secondary to left ventricular heart disease (type 2 pulmonary hypertension) with congestive hepatopathy and cardiac ascites was made.

The patient’s physical examination provided an important clue to the etiology of the ascites – cardiac ascites is thought to be due to chronic venous congestion of the liver due to transmission of high central venous pressures. Tricuspid regurgitation can be associated with severe hepatic congestion because of retrograde transmission of right ventricular pressure directly into the hepatic veins. In some patients (although not in this patient), careful examination will reveal that the liver in such patients is palpably pulsatile.

Cardiac ascites is typically characterized by a serum albumin gradient (SAAG) >1.1 g/dL (indicative of portal hypertension) and ascites protein level of >2.5 g/dL (1). We cannot fully explain why this patient’s SAAG was low. A complete workup for infectious and oncological etiologies of low SAAG ascites was negative. It has been noted that in patients with known cirrhosis (as in this patient), the finding of a low SAAG has a low specificity for infectious and oncological etiologies of ascites (2). Serositis which can sometimes manifest as ascites can also be a complication of tacrolimus which the patient was receiving s/p renal transplant. It’s possible that tacrolimus might have changed the nature of the ascites fluid in this patient but this is conjectural. 

Robert A. Raschke, MD

College of Medicine-Phoenix

Phoenix, AZ USA

References

1. Sam AH, James THT. Rapid Medicine. Wiley-Blackwell; 2009: ISBN 1-4051-8323-3.
2. Khandwalla HE, Fasakin Y, El-Serag HB. The utility of evaluating low serum albumin gradient ascites in patients with cirrhosis. Am J Gastroenterol. 2009 Jun;104(6):1401-5. [CrossRef] [PubMed] 

Cite as: Raschke RA. Medical image of the week: cannon V waves. Southwest J Pulm Crit Care. 2017;15(2):90-1. doi: https://doi.org/10.13175/swjpcc095-17 PDF