Medical Image of the Week: Metastatic Collecting Duct Carcinoma

C

Figure 1. Transverse section of CT chest and abdomen shows enhancing pleural nodularity (yellow arrows) with a pleural effusion.

Figure 2.  Transverse section of CT abdomen shows heterogeneous enhancing mass in the right kidney (red arrow).

Figure 3. Coronal section of CT chest and abdomen showing a large right pleural effusion (yellow arrow) and atelectatic lung with mediastinal shift to the left. Red arrow points to the heterogeneous mass in the right kidney.

A 40-year-old woman home health nurse presented to the ED with intermittent right sided sharp chest pain and progressive dyspnea for 2 weeks. On admission she was found to be in respiratory distress. Chest x-ray revealed a massive right sided pleural effusion. Thoracic CT scan with contrast confirmed a large right pleural effusion with associated enhancing pleural nodularity also involving the diaphragmatic surface (Figure 1).  The visualized part of the abdomen revealed a mass in the midpole of right kidney (Figure 2). Subsequent CT scan of the abdomen with contrast revealed a heterogeneous enhancing mass in the right kidney suspicious for malignancy (Figure 3) and multiple paracaval lymph nodes. Thoracentesis revealed a hemorrhagic pleural effusion and during subsequent right video-assisted thoracoscopy showed disseminated tumorlets along the diaphragm and pleura. Pleural biopsy and fluid cytology was consistent with metastatic poorly differentiated collecting duct carcinoma of the kidney. The patient is currently getting outpatient chemotherapy. Collecting duct carcinoma of the kidney is an unusual variant of renal cell carcinoma and accounts for about 1% of all renal cell carcinomas (1). This variant has a poor prognosis and frequently metastasizes to the lung and liver.

Chandramohan Meenakshisundaram, MD

Nanditha Malakkla, MD

St. Francis Hospital.

Evanston, IL

Reference

1. Wang X, Hao J, Zhou R, Zhang X, Yan T, Ding D, Shan L, Liu Z. Collecting duct carcinoma of the kidney: a clinicopathological study of five cases. Diagn Pathol. 2013;8:96. [CrossRef] [PubMed]

Reference as: Meenakshisundaram C, Malakkla N. Medical image of the week: metastatic collecting duct carcinoma. Southwest J Pulm Crit Care. 2014;9(6):348-9. doi: http://dx.doi.org/10.13175/swjpcc160-14 PDF

Medical Image of the Week: CMV Cytopathic Effect

Figure 1. Cluster of 3 large cells, most likely infected type II pneumocytes, with a single prominent red stained nuclear inclusion surrounded by a clear halo. This appearance is the “cytopathic effect” needed to definitively diagnose active CMV infection.

Figure 2. Electron microscopy (8800x) of an infected cell showing  cytomegalovirus (CMV) virions within the nuclear inclusion (small black dots encircled).

Bronchoalveolar lavage (BAL) was performed on a 45-year old man with a history of treated mycosis fungoides and Sézary syndrome, who presented with fever and pulmonary infiltrates. BAL Papanicolaou stain (Figure 1, 400x) showed single cells (lymphocytes, arrows and alveolar macrophages, stars) and a small cluster of 3 large cells, most likely infected type II pneumocytes, with a single prominent red stained nuclear inclusion surrounded by a clear halo. Nuclear chromatin was marginated on the nuclear membrane creating this “owl’s eye” appearance. In vitro, infected cells show cytomegalovirus (CMV) virions within the nuclear inclusion (Figure 2, small black dots encircled, 8,800x)

The "owl's eye" appearance (Figure 1) is the “cytopathic effect” needed to definitively diagnose active CMV infection. While cells infected with adenovirus or herpesvirus may have nuclear inclusions, the cells typically are much smaller. CMV was cultured from the BAL, and no other pathogen was identified by cytology or culture. Quantitative PCR on blood for CMV was 144359 IU/ml.

Afshin Sam, MD; Felicia Goodrum, PhD; Robert Ricciotti, MD; Ken Knox, MD and Richard Sobonya, MD

Departments of Medicine, Immunobiology, and Pathology

University of Arizona Health Sciences Center

Tucson, AZ

Reference as: Sam A, Goodrum F, Ricciotti R, Knox KS, Sobonya R. Medical image of the week: CMV cytopathic effect. Southwest J Pulm Crit Care. 2014;9(6):341-2. doi: http://dx.doi.org/10.13175/swjpcc161-14 PDF