Case Study

RAD – Severe military lung pattern with peribronchial cuffing and hypovolemia, likely neoplastic, in a 12 year old MN Labrador dog

This 12 year old MN Labrador dog had a splenectomy Jan 2016 with histopath showing regionaly extensive acute to subacute coaglative necrosis consistent with infarct. There were no overtly neoplastic cells, obvious vasculitis, or site of vascular thrombosis but systemic disease was of high concern. CBC/Chem at the time: HCT 35% with reticulocytosis, platelets 85 K/uL. On blasto antigen test dog was negative on 2/22/16.

Rads looked similar to today and dog was coughing and temp of 103. Responded some to cephalexin/aminophylline, and temaril P.

Physical Exam: Heart and lungs auscult WNL, no coughing but dog weaker at home and grunting at times and seems uncomfortable. Gums pale pink but QAR with temp 101.6 on exam.

CBC: Hct 20.5%, Hgb 6.6, Retic 454 K/uL, Neut22.42, Lymph 6.12, mono 4.28, platelets 36 Chemistry: NSF

Image Interpretation

Rads of the thorax and abdomen – The osseous structures present the expected age related changes.
The degree of lung inflation is moderate. The overall opacity of the lung is increased.
There is a severe generalized miliary pattern composed of multiple interstitial nodules
of varying size up to 5 mm and peribronchial cuffing throughout the lung. No
tracheobronchial/mediastinal lymph node enlargement is seen. The mediastinum is
normal in width. The cardiac silhouette and pulmonary vessels are obscured by the
lung pattern. The cardiac size and shape are within normal limits. The caudal vena
cava and pulmonary vessels appear to be thin. There is no evidence of pleural effusion.
The spleen is not seen in the cranial abdomen. Otherwise the cranial and mid abdomen
are within normal limits.

DX

Severe military lung pattern with peribronchial cuffing; hypovolemia with underperfusion of the lung

Outcome

Given the history metastatic neoplastic infiltration is very likely (even though the
histopathology of the spleen prove negative. False negative histopathology has to be
assumed here and is quite common in splenic hemangiosarcoma or other splenic
malignancy). Another secondary neoplasia (mainly round cell neoplasia) would be a
possible differential diagnosis even if lower for potential.
The chances of this being a fungal or mycobacterial pneumonia are extremely low
given the lack of pleural effusion and mediastinal lymph node enlargement